Setup for Linn LP12?

The armboard and platter axes are fixed by the subchassis. If one is level and the other is not, then the subchassis, plinth or top plate is bent or the armboard/main bearing is not installed correctly. There's not much to go wrong here if all the parts are good and installed correctly. Make sure the grommets are properly seated. The top plate sags in the middle so this might give the impression of a downward slope from the middle to the front (but also the middle to the back). Good Luck!

-- Analogue Addicts Linn LP12 FAQ Last updated 30 April 1997 ============================== Status: Draft Analogue Addicts is a mailing list dedicated to the discussion of high quality reproduction of music by analogue means. The major musical source for the members on the list is the vinyl LP played on a turntable. Many members of the list have high quality turntables and among these is the Linn LP12. Some members of the list have produced FAQ's for their make of turntable. The Linn LP12 has a long and varied history and requires to be "set-up" correctly to achieve best results. The questions from the list about the LP12 and how to set it up have resulted in the compilation of this FAQ. Neither the compiler nor the contributors are in any way responsible for any damage or loss caused by following the advice in this document. Before working on your turntable think about what you are going to do, make sure you understand the process and what consequences it might have. Copying and reproduction is allowed and encouraged, provided the entire document is copied without any change to its contents. To contribute to this document please send suggestions, additions and corrections to its compiler Neil J Mackie by email at [email protected]. If you think some topic is missing compose a section yourself, or ask the list, compile the replies and send them to Neil J Mackie. A list of those contributing, intentionally or unintentionally, to this document is given at its end. Table of Contents ----------------- FAQ introduction, disclaimers and table of contents Contacts - AA, Linn, the FAQ compiler History of the LP12 Identifying the LP12's parts Product Information & reviews Turntables (Linn only) Power supplys (Linn & non Linn) Arms (Linn & non Linn) Cartridges (Linn) FAQs about Turntables about Power supplys about Arms about Cartridges Identifying LP12 parts Setup of Turntable of Arm of Cartridge Upgrades Turntable Arm Cartridge Pawer Supply Tweaks & DIY List of contributors Contacts ======== How do I obtain the file containing this FAQ? --------------------------------------------- Send the message get analogue-addicts lp12faq.txt to [email protected] . As this file is about 67k in size there are two alternative files available. lp12faq.uue is a uuencoded version of the compressed version of the file. lp12faq.ZIP is a uuencoded version of a zip archive containing the file. These can be obtained by substituting the appropriate name in the command above. See the next question about how to find out more about majordomo. How do I subscribe to the Analogue Addicts mailing list? -------------------------------------------------------- Send the message subscribe analogue_addicts your_mail_address to [email protected] . For further information on the commands understood by majordomo send the message help Is there a FAQ for the Analogue Addicts mailing list? ----------------------------------------------------- No, but there are archives located at http://www.york.ac.uk/~mjgw100/aaa.htm. Some files are available from [email protected]. See above to find the command to retrieve these. How can I contact Linn? ----------------------- Linn can be contacted by email at [email protected] and have a WWW site at http://www.linn.co.uk/linn. If you are remote from Scotland which is where Linn are based the site http://www.macom.co.il/Stereo/Equipment/linn.products.html may be more accessible. History of the LP12 =================== Origins ------- There used to be a saying among the Scottish hi-fi community that the engineers coming out of university turned left to go to Heybrook and right to go to Linn. Despite the apocryphal nature of this anecdote, the truth is, the two designs share a number of things in common. They are both three point sprung suspensions as both are based on the original AR white paper for transcription turntables. They both use a wood plinth which looks similar, a two-piece platter, and identical dust covers (except for the logo--LP12 Vs TT2). The differences are in the details. The Heybrook TT2 has a massive sub-chassis compared to the Linn. It is very thick aluminium compared to the thin steel Linn use. The TT2 plinth is constructed of 1" thick MDF with a wood veneer, the LP12 of solid wood, usually English ash. In addition, most of the cavities inside the chassis of the TT2 are filled with shaped wood blocks, in the Linn they are not. The springs in the TT2 are stiffer and can be adjusted from the top plate using a 5mm Allen key. The springs of the Linn are adjusted from below by nuts. The top plate on the TT2 is much thicker than the Linn and black. The TT2 has a transport screw for locking down the suspension when shipping. The LP12 does not. The armboard in the TT2 is thicker but shorter while the LP12 arm board is the full front to back depth of the plinth. It is non-laminated like the older Linn armboards, but unlike the Linn, the Heybrook arm board is made of a plywood sandwich not MDF. Later models had dif! ferent power supply arrangements . The TT2 bearing and platter are not so heavy as the Linn nor so finely machined. The oil is lighter weight than the Linn bearing oil. As far as sound quality goes, the TT2 is like a Linn. It has warmth and rhythmn and coloration. It is very comparable to an early Linn LP12 with Basik power supply. It lacks the refinement of the later Linns and the bass foundation of a better power supply, such as the Lingo or Armageddon. Product Introduction and Production Dates ----------------------------------------- (dates and serial numbers are approximate) 1973 LP12 turntable introduced. [ 2,000] 1974 Main bearing liner changed, sub-chassis strengthened, motor control and mains switch changed. [23,000] 1978 Top plate modified [27,000] 1979 Lid and hinges changed. [31,826] 1981 February. Nirvana mechanical components. This consisted of 1 new spring kit (3 springs & 6 grommets), 3 large locknuts, 6 small locknuts, 5 black chassis bolts, 2 motor mounting screws, domes, & nuts allowing it to be positioned with better accuracy. 1 motor thrust bearing kit (endcap, spring, ball bearing). 1 new drive belt. The springs changed from zinc coloured to black. [38,794] 1982 May Valhalla crystal driven electronic power supply made standard. [53,000] 1984 Enlarged plinth corner bracing. [54,101] 1984 June. Sub-chassis strengthening bar epoxy glued instead of spot welded. [60,383] 1985 August. Cap head screws on bearing housing. [61,090] 1985 September. Diode modification to Valhalla. [n/a] 1985 December. Strengthening blocks on corners of plinth. 1986 Suspension springs improved. [n/a] 1986 May. New clear lid. [69,161] 1987 March New Formica and MDF armboard. [n/a] 1987 March New bearing housing. [69,591] 1987 April New springs. [70,000] 1987 Bearing improved with better lining material and tighter tolerances. Change to black oil. Suspension springs improved. Arm board composition improved. [79,160] New MDF armboard. [79,700] 1989 Motor thrust pad changed. Valhalla surge guard modification. PCB mains lead (UK). [81,000] 1989 Harder suspension grommets fitted. [n/a] 1990 Lingo power supply available as add-on. [87,047] 1991 Valhalla with 45. [87,047] motor thrust pad cap added to Lingo models. [87,206] motor thrust pad cap added to Valhalla models. [87,672] Introduction of LP12 Basik, Trampolin available. [87,672] Solid base board replaces hardboard. [88,950] 1992 Improved top plate fixing. Linn LP12 Basik introduced. [90,582] 1993 Cirkus upgrade fitted as standard. Identifying the LP12's parts ============================ arm - this is not strictly part of the LP12 as a variety of arms can be fitted to it. The function of the arm is to hold the cartridge above the record. The quality of the arm affects how vibrations are transmitted to and from the cartridge and has considerable effect on the sound. arm board - this is the part to which the arm is attached and fixes the arm to the sub chassis. It also supports the arm rest if the arm rest is not already part of the arm and completes the turntables top surface filling the gap left by the top plate. bearing - the bearing supports the platter both vertically and horizontally and connects the platters spindle with the sub chassis. The bearing must support the platter and allow the platter to rotate freely with little friction. It must support the sides of the spindle tightly enough to couple the spindle to the sub-chassis but smoothly enough so it does not generate any noise. motor assembly - The motor drives the inner platter via a belt. The motor used is the same design as used in the original LP12. Originally made by Philips subsidiary Impex the company was later sold to Airpax. List members have measured the motors resistance at 8.8Kohms and inductance at 10H. platter - the platter is the part that spins and supports the record. The LP12 has a two part platter. The inner platter has a spindle which locates in the bearing and is the part that is driven by the belt from the motor. The outer platter fits on top of the outer circumference of the inner platter extending its top area to the size of a 12inch record and providing the rotational inertia. "The platter takes a month to produce, as it is turned, then put away, then turned, and put away, and on and on, till the machining is complete. This is because they want the metal to remain UNSTRESSED, so as to avoid a severe resonant peak in the metal's structure, due to overheating. Replace the undamped platter on the inner platter, and give it a tap, and you will see how fast the noise dies down, without a long decay period." plinth - this is the wooden bit that forms the frame of the turntable. It has a series of square section channels routed along the sides and front giving the LP12 its distinctive look. power supply - The power switch is the best way of determining which PSU an LP12 is fitted with. The Nirvana supply has a large square illuminating switch. The Valhalla has a black square with a small red LED in the middle. The Lingo has a black square switch with one small red LED and one small green LED. The Lingo is also enclosed in an external box rather than being situated in the plinth itself. springs - the turntable has three springs which support the sub chassis at their top and are supported by bolts attached to the top plate. top plate - this is a steel plate the forms the top surface of the turntable. It has holes in it through which the bearing and motor assembly protrude. It forms the fixing points for the suspension bolts. The top plate is deliberately made slightly oversize for the plinth and when it is fitted it bows down slightly near the arm board. This is done to minimise vibration. Turntables ========== The LP12 began as a single model but was later improved with more sophisticated motor power supplys. This later became formalised with three versions of the LP12 available LP12 Basik ---------- Description: The LP12 Basik was introduced in 1991 as an entry level LP12. Date of introduction: 1991 Power Supply: Resistor / capacitor network as used before the Valhalla power supply was introduced. Speed accuracy: linked to tolerance of supply. Price: Afro:579 Walnut:599 Black:609 GBP (1992) LP12/Valhalla ------------- Date of introduction: 1984 Power Supply: Valhalla inboard crystal driven electronic speed control. Speed accuracy: 0.03% Price: LP12 Lingo ---------- Date of introduction: 1990 Power Supply: Lingo outboard crystal driven electronic speed control with 33/45 rpm speed selection. Speed accuracy: 0.01% Price: 1248 GBP (1991) Power Supplys ============= One area of variation of LP12s is the motors power supply (as is obvious from the section above). It is claimed that the power supply makes a large difference to the sound of the turntable. Linn have brought out a number of power supply variations as have a number of third party vendors. These are listed below. Linn Supplys ------------ Basik ----- Description: A basic resistor / capacitor network designed to provide voltages with the required magnitude and phase to run the motor. Date of introduction: Price: 20 GBP (1992) Lingo ----- Description: Date of introduction: Features: Electronic speed change between 33 & 45 rpm. Price: 496 GBP (1991) 559 GBP (1992) "Using the Valhalla, the presentation is nice - it has a full atmospheric bass quality. Changing to the Lingo improves the sound quality in every area by a big margin, BUT it changes the presentation so that it is much leaner in the bottom end." "When I moved from Valhalla to Lingo I was stunned by the magnitude of the change. The apparent dynamic performance was markedly better, blacker blacks between notes, more communication of emotion, everything just pounded along. Far less watery modulation of piano etc. You know then that the PSU is of major importance." Valhalla -------- Description: Date of introduction: 1984 Price: 180 GBP (1992) Other supplys ============= Avondale PSU ------------ Description:The Avondale power supply is a unit that conditions the mains supply while reducing its level so it is suitable for supplying to the motor. The output level is variable. Date: Features: Uses capacitor phasing. Available from Avondale Audio, The Hollies, Avondale Road, Chesterfield, Derbs., S40 4TF, United Kingdom. "The Avondale power supply contains a circuit which is difficult to see the details of. However from the mains input it appears to run through a fuse and through some conditioning circuitry as there appears to be a varistor as well as some resistors and capacitors which would clean up any voltage spikes. There is then an on/off switch and led indicator. The supply then goes to the first of two transformers. After this there is a pair of circuits comprising power resistor, diodes and capacitors forming a resonant circuit before a second transformer. After this another power resistor, capacitor, diode arrangement feeds a stepped attenuator and from there the output socket" Heybrook TT2 ------------ Pink Triangle Pink Linnk ("Plink") ---------------------------------- Description:"The Pink Linnk PSU is a DC battery based PSU. Pink Triangle install a new top-plate with a DC motor. The PSU provides 33 and 45 speed selection." Price:450 GBP." Pink Triangle Projects on (+44) 171 703 5498. Manticore MB5i -------------- Description: External electronic power supply for AC synchronous motors. A crystal controlled clock is divided down to give 50 and 67.5Hz square waves. These are converted into pure sine waves using op-amp filters. The 90 degree phase shift which is optimum for AC synchronous motors is obtained using a phasing capacitor. The signals are then amplified by high voltage bridge amplifiers. Date of introduction: Features: Electronic speed change between 33 & 45 rpm. External power supply. Phasing achieved using capacitor. Price: 320 GBP (1996) Manticore MB6 ------------- Description: External electronic power supply for AC synchronous motors. A crystal controlled clock is divided down to give 50 and 67.5Hz square waves with 90 degree phase shift. These signals are converted into pure sine waves using op-amp filters. They are then amplified by high voltage bridge amplifiers. Date of introduction: Features: Electronic speed change between 33 & 45 rpm. External power supply. Phasing achieved without capacitor. Price: 520 GBP (1996) "The Manticore MB6 which can also be used on LP12s. The only thing I can say is that it was a large improvement over the normal resistor + capacitor network. The designer Doug Hewett claims that it is better than the Lingo." Manticore MB6i -------------- Description: Date of Introduction: Features: Electronic speed change between 33 & 45 rpm. External power supply. Phasing achieved without capacitor. Price: 670 GBP (1996) MAV Shareholders Ltd, The Old Tinsmiths, Shortmead St, Biggleswade, Beds, SG18 0AP. (+44) 1767 318 437 fax (+44) 1767 318 462. Naim Armageddon --------------- Price: 1000 USD (1996) "Now, moving to the Armageddon [from a Lingo] I notice: a) different timing, more in keeping with Valhalla so you have an element of re-learning. b) Massive improvement in textural characteristics of instruments. e.g. subtle creaking noises in the case of a piano, all resonances in the case etc. Much more real. c) More detail recovery and the loss of a slight veiling that I now think the Lingo adds. d) Easier power arrangements. Armageddon loves to sit on the same spur as the rest of your kit. [the Lingo is best on a separate spur]" Naim Arms ==== Linn Arms --------- Akito, Akito II ----- Description: Entry level arm. Date of introduction: 1989 Effective mass: 10g Suitable cartridge weights: 2 - 10g Pivot to stylus length: 229mm Overhang: 18mm Features: Price : 137 GBP (1992) "The Akito does not happen to be lucky with moving coil cartridges. The Akito II may fare a bit better, but then it should, as it costs a lot more than the old version." Ittok LVII, LVIII & LVIII/2 --------------------------- Description: Top of the range arm. Later superseded by the Ekos. Date of introduction : 1979 Effective mass: 11.5 g Suitable cartridge weights: 3 - 9g Pivot to stylus length: 229mm Overhang: 18mm Features: Controls for tracking weight and anti skate. VTA adjustable by unclamping arm pillar via grub screw. Price: Silver LVIII 560 GBP (1992) The Ittok came first as LVII, later replaced by LVIII and finally (for a short period) as LVIII/2 with Ekos-type arm-rest (no hole in the arm board needed). The Ittok LVII has a mark 1 and mark 2 series. The mark 1 has a two piece counter weight, a smaller diameter pillar, and a 5 mm set screw in the arm collar to name a few features which make it easy to distinguish from a later mark 2. The LVII also existed in black. They were more expensive as new and are very rare. Only 1000 were made. There were also a few black LVIIIs. Ekos ---- Description: Top of the range arm. Date of introduction: 1988 Effective mass: 11.5g Suitable cartridge weights: 4 - 9g Pivot to stylus length: 229mm Overhang: 18mm Features: Price: 1097 GBP (1992) " The Ekos exists in two generations but the arm wasn't renamed. Ekos II came around 1992, Ekos with serial numbers above 6490 should be IIs. The improvement is changed bearings and the difference is IMO significant. I don't know of any improvements since. Linn offered rebuilding to the new bearings." LVV --- Description: Introductory level arm. Date of introduction: Effective mass: Suitable cartridge weights: Pivot to stylus length: Overhang: Features: Price: LVX --- Description: Budget arm. Improved version of the LVV. Date of introduction: Effective mass: Suitable cartridge weights: Pivot to stylus length: Overhang: Features: Price: 75 GBP (including Basik cartridge) (1984) LVX Plus (Basik Plus) --------------------- Description: Improved version of LVX with fixed headshell and more substantial bearing. Date of introduction: Effective mass: Suitable cartridge weights: Pivot to stylus length: Overhang: Features: Price: 86 GBP (including Basik cartridge) (1984) Other Arms ---------- AudioQuest PT ------------- Description: Date of introduction: Effective mass: Suitable cartridge weights: Pivot to stylus length: Overhang: Features: Price: "I've been told the AudioQuest PT arms work well on the LP12 and are easy to mount." Naim Aro -------- Description: A unipivot arm. Date of introduction: Effective mass: Suitable cartridge weights: Pivot to stylus length: Overhang: Features: Price: 779 GBP (1992) The Naim Aro is a unipivot i.e. when in use the arm is supported at a single point other than the stylus. "a softer and sweeter balance than comparable gimbal bearing arms" Rega RB300 ---------- Description: Date of introduction: Effective mass: Suitable cartridge weights: Pivot to stylus length: Overhang: Features: Price: "Contrary to many views the Rega RB300 (new one) *can* be fitted and sounds excellent." "the RB-300 easily can sport multi-$ cartridges" Zeta ---- Description: A contemporary of the Ittok made by "a London garage company". However it suffered with quality control problems especially with the bearing adjustment. Date of introduction: Effective mass: Suitable cartridge weights: Pivot to stylus length: Overhang: Features: Tracking force and anit skate controls have no scales. Price: "When adjusted well, it outperforms an Ekos arm. It has the same bass dynamics and imaging, but very smooth and lush midrange and treble in contrast to an Ekos 1 with a very detailed, analytical midrange or the Ekos 2 with its lack of treble." What is the correct arm board cut out and geometry for my arm? -------------------------------------------------------------- It depends on the arm. Some are listed below. Akito ----- Ekos ---- Ittok ----- Rega RB300 ---------- The distance from the centre of the spindle to the centre of the mounting hole is 8.76 inches. The mounting hole is 23mm diameter. I don't have one of the arms listed above - what should I do? ------------------------------------------------------------ Luckily one of the list members Rex, has produced a table. Look up the length of your arm (arm pivot point to stylus diamond) in the table to get the best geometry. Alternately if you already have an arm fitted measure the arm pivot to platter centre distance and use the first column to determine the arm length. "The following is intended as a guide to those setting up arms on turntables. The numbers are generated using a non-linear function optimisation algorithm. The column marked Dst is a relative indication of the error caused by the geometry (objective function), and the columns marked Null are the two points from the centre of the platter at which the stylus is tangential. The easiest way I have found to set up a turntable is to get the effective arm length correct (that is pivot to diamond), then twist the cartridge in the headshell so that the stylus lines up correctly on a protractor at the two null distances (fortunately always around the same number). Note that the Overhang column is not projected into the vertical plane parallel with the cantilever." Platter to arm pivot | Arm length | Offset | Dst | Overhang | Null | Null (mm) | (mm) | (deg) | | (mm) | (mm) | (mm) ----------+------------+--------+-----+----------+------+----- 210.0 | 229.0 | 24.2 |1.094| 19.0 | 73.1 |115.8 211.0 | 230.0 | 24.1 |1.090| 19.0 | 73.1 |115.8 212.0 | 230.9 | 24.0 |1.085| 18.9 | 73.1 |115.8 213.0 | 231.8 | 23.9 |1.080| 18.8 | 72.4 |115.8 214.0 | 232.8 | 23.8 |1.074| 18.8 | 73.1 |115.8 215.0 | 233.7 | 23.7 |1.069| 18.7 | 73.1 |115.8 216.0 | 234.6 | 23.6 |1.065| 18.6 | 72.4 |115.8 217.0 | 235.5 | 23.5 |1.060| 18.5 | 73.1 |115.8 218.0 | 236.4 | 23.4 |1.055| 18.4 | 72.4 |116.4 219.0 | 237.4 | 23.3 |1.050| 18.4 | 73.1 |115.8 220.0 | 238.3 | 23.3 |1.045| 18.3 | 73.1 |116.4 221.0 | 239.2 | 23.2 |1.041| 18.2 | 73.1 |116.4 222.0 | 240.1 | 23.0 |1.035| 18.1 | 73.1 |115.8 223.0 | 241.0 | 22.9 |1.029| 18.0 | 73.1 |115.8 224.0 | 242.0 | 22.9 |1.026| 18.0 | 72.4 |115.8 225.0 | 242.9 | 22.8 |1.022| 17.9 | 73.1 |116.4 226.0 | 243.8 | 22.7 |1.017| 17.8 | 73.1 |115.8 227.0 | 244.7 | 22.6 |1.012| 17.7 | 72.4 |115.8 228.0 | 245.7 | 22.5 |1.008| 17.7 | 72.4 |115.8 229.0 | 246.6 | 22.4 |1.002| 17.6 | 72.4 |115.8 230.0 | 247.6 | 22.3 |0.999| 17.6 | 73.1 |115.8 231.0 | 248.5 | 22.3 |0.995| 17.5 | 73.1 |116.4 232.0 | 249.4 | 22.1 |0.989| 17.4 | 73.1 |115.8 233.0 | 250.3 | 22.0 |0.984| 17.3 | 72.4 |115.8 234.0 | 251.3 | 22.0 |0.981| 17.3 | 72.4 |115.8 235.0 | 252.2 | 21.9 |0.977| 17.2 | 73.1 |115.8 236.0 | 253.1 | 21.8 |0.973| 17.1 | 72.4 |115.8 237.0 | 254.1 | 21.7 |0.969| 17.1 | 73.1 |116.4 238.0 | 255.0 | 21.6 |0.965| 17.0 | 72.4 |115.8 239.0 | 255.9 | 21.5 |0.960| 16.9 | 73.1 |115.8 240.0 | 256.9 | 21.5 |0.957| 16.9 | 73.1 |116.4 241.0 | 257.8 | 21.4 |0.952| 16.8 | 73.1 |115.8 242.0 | 258.7 | 21.3 |0.949| 16.7 | 73.1 |115.8 243.0 | 259.7 | 21.2 |0.945| 16.7 | 73.1 |116.4 244.0 | 260.6 | 21.2 |0.941| 16.6 | 72.4 |115.8 245.0 | 261.6 | 21.1 |0.937| 16.6 | 72.4 |116.4 246.0 | 262.5 | 21.0 |0.933| 16.5 | 73.1 |115.8 247.0 | 263.4 | 20.9 |0.930| 16.4 | 72.4 |116.4 248.0 | 264.3 | 20.8 |0.925| 16.3 | 73.1 |115.8 249.0 | 265.3 | 20.8 |0.922| 16.3 | 72.4 |115.8 250.0 | 266.2 | 20.7 |0.918| 16.2 | 73.1 |116.4 I have heard rumours that the bearings in some tonearms disintegrate due to the vibrations from a moving coil cartridge. Is this true? -------------------------------------------------------------------------------- No. "Many moving coil cartridges (MCs) tend to have lower compliance figures than moving magnet cartridges (MMs), and a few MCs are deliberately designed to dump a lot of mechanical energy into the tonearm. But even something like the Deccas will put a lot of energy into the tonearm, and these are certainly not MCs. In any case, if the tonearm suffers from loose bearings or bearing rattle, the tonearm will not be able to control the mechanical energy from the cartridge properly, and the result will sonically not be as good as it would be in a tonearm with a better bearing system. Note that this is NOT the same thing as disintegrating bearings. Unless the bearings were cracked to begin with, the tonearm should remain in good health regardless of whatever kinds of cartridges were used). However, it IS possible to create a flat spot on a bearing through user abuse. This usually occurs when the user (most likely while installing or adjusting a cartridge) puts too much stress on a gimballed-bearing tonearm which has bearing tolerances that are very close or a little on the tight side and bearings that are not as mechanically hard as they should be. The factors determining the susceptibility of gimballed bearings to loose bearings or bearing rattle is the bearing precision, hardness and wear. In unipivots the main factor is the amount of pressure (usually the force of gravity) applied to the bearing, but in most unipivot tonearms, loose bearings or bearing rattle will not exist. Tonearms which are immune to loose bearings or bearing rattle because of their fundamental design include the Naim ARO, the Morch UP series, the Ultracrafts/Audiocrafts, the Wilson-Benesch and the Graham. I suppose that there are others as well, including the Well-Tempereds, probably the Roxans, and many others that I simply don't know about. Gimballed arms like the Linns, SMEs, Regas etc. can and do have excellent bearing performance, but for top performance, the bearings do tend to demand a higher degree of execution than a unipivot. A final note - be wary of tonearms with excessive bearing friction, or tonearms with no anti-skating (which I believe unfortunately includes the new VPI JPW Memorial tonearm), as these can and will gradually damage your records and the cartridge suspension. As I may have mentioned in a previous posting, tonearms with undamped lift mechanisms are also a no-no for many precision cartridges." How can I check an arm for bearing damage? ------------------------------------------ NOTE: It is very important that you use utmost care in conducting these tests to prevent the arm from flying away and damaging itself. It is advisable to carry them out with your cartridge's stylus guard in place. "One method you might use is to balance your arm so that the cartridge floats above the records surface with zero tracking force and zero anti-skating force. Then gently nudge it in either direction (using your other hand to prevent it from going too far) and observe how it reacts to horizontal movement. Then go ahead and apply some anti-skating force and see if the arm moves outward from the inner grooves. It should move outward with just a very slight amount of anti-skating force applied if the horizontal bearing is working properly. You can also assess the operability of the anti-skating mechanism during this test, as well. Perhaps it is applying too much force outward. Additionally, you should check the vertical bearings by placing a small piece of paper (one square centimetre) on the headshell and observing that the arm moves downward slightly. If it does not, try a couple of pieces of paper, but if it takes any more than two, this may indicate excessive friction in the ! vertical bearings. A properly f unctioning arm will exhibit extremely low friction in all directions." Cartridges ========== Most cartridges can be fitted to a LP12, however some cartridges are more popular on LP12s than others. Linn also produced their own cartridges. This section has details about the Linn cartridges and others popular on LP12s. Linn Cartridges --------------- Arkiv ----- Description: A moving coil cartridge. Top of the range model replacing the Troika but said to be "a very substantial improvement over it". This is the only cartridge that Scan-Tech designed and builds for Linn. "Among the other cartridges that Scan-Tech have done, probably the most similar ones in concept (if not in execution) to the Arkiv are the Spectral MCR family and our own Lydian." "The Arkiv uses a system in which the magnet and generator assembly are bolted directly to a skeletal aluminium block that serves as both chassis and exterior housing. As it does not have a plastic sub-chassis, the Arkiv's generator system suffers from less resonance and less monkey movement than the Troika (although I wouldn't be surprised if the resonance and monkey motion are exactly the things that endear the Troika to its proponents). The clear plastic piece on the front of the Arkiv is a non-structural element designed primarily to protect the internal components of the cartridge." Date of introduction: 1992 Output: 150 micro V Compliance: 10 cu Tracking weight: 1.55 - 1.75 g Loading: >50 ohms Weight: 7.4 g Price: 998 GBP (1994) Asak ---- Description: A moving coil cartridge, top of the range in the early 80s. Plastic body. Date of introduction: 1985 Output: 100 micro Volts Compliance: 10cu Tracking weight: 1.5 - 1.7g Loading: >10 ohms, nominal 150 ohms, 560 ohms & 6800pF with Naim amps. Weight: 7g Price: 218 GBP (1984) Asak T ------ Description: moving coil. An Asak but put together better. Date of introduction: Output: 100 micro volts Compliance: 10cu Tracking weight: 1.5 - 1.7g Loading: >10 ohms, nominal 150 ohms Weight: 7g Price: Asaka ----- Description: A moving coil cartridge, a successor to the Asak. It has an aluminium body and a better fitting cover than the Asak which has a metal cover that is quite easy to remove. Date of introduction: Output: Compliance: Tracking weight: 1.6 - 1.7 g Loading: > Weight: Price: 260 GBP (1987) 373 GBP (1992) Basik ----- Description: moving magnet. Initially a 'freebe' cartridge given away with LVV and LVX arms. Later improved in the yellow bodied version. Date of introduction: . Yellow Basik 1983. Output: Compliance: Tracking weight: Loading: Weight: Price : 13 pounds (1984) K5 -- Description: entry level moving magnet Date of introduction: 1988 Output: 4.5 mili V Compliance: 14 cu Tracking weight: 1.5 - 2.0 g Loading: 47 kilo ohms Weight: 5.8 g Price: 39 GBP (1992), replacement stylus 24 GBP (1992) K9 -- Description: moving magnet. Made by Audio Tech. Date of introduction: 1986 Output: 4.5 milli Volts Compliance: 12 cu Tracking weight: 1.5 - 2.0 g Loading: 47 kilo ohms Weight: 7.1 g Price: 59 GBP (1986), 89 GBP (1992), replacement stylus 55 GBP (1992) K18 --- Description: moving magnet Date of introduction: 1988 Output: 4.5 mili V Compliance: 12 cu Tracking weight: 1.5 - 2.0 g Loading: 47 kilo ohms Weight: 7.9 g Price: 155 GBP (1992), replacement stylus 84 GBP (1992) K18/II ------ Description: moving magnet Date of introduction: 1992 Output: 4.5 milli V Compliance: 12 cu Tracking weight: 1.5 - 2.0 g Loading: 47 kilo ohms Weight: 7.5 g Price: 155 GBP (1992) Karma ----- Description: low output moving coil. Superseded Asak as top of the range. Looks like Asak and has aluminium cantilever. Unlike the Asak it has a solid aluminium body, more powerful magnet and different pole piece geometry. As opposed to previous Supex cartridges badged as Linn this was the first designed by Linn and manufactured by Supex. Date of introduction: 1983 End of production: 1986 Output: 200 micro V (1kHz 5cm/s) Compliance: Tracking weight: 1.5 - 1.7 g Loading: 470 ohms recommended, 680 ohms & 1000pF with Naim amps. Weight: 6.2 g Price: (GBP) 293 (1984) 345 (1985) 399 (1987) (DM) 1100 (1983) Channel balance : 0.25dB Channel separation (L,R): 30, 30dB Tracking ability (L,R): 80, 76um Frequency response 100Hz-5kHz +2,-1dB Frequency response 30z-20kHz +2,-2dB Separation L or R 100, 3k 10kHz: 30, 33, 35dB Separation R on L 100, 3k 10kHz: 32,37, 33dB Channel difference 100, 3k, 10kHz: 0, 0, 0.5dB Response limits ref mean 1k-15kHz: +1, -0dB Response limits ref mean 1k-20KHz: +2.5, -0dB LF resonance 12.5g arm (vert,lat): 11.5 11.5 Hz Estimated compliance (vert, lat): 12, 12 cu Recommended arm effective mass: 9-18 g Low freq resonance rise 12.5g arm (vert, lat): 15.5, 14.5 dB "Downforce of 1.7g, which gave adequate tracking abilities but left little in hand." "Frequency response is smooth but with a fairly large 3dB downtilt, running from 100Hz to 5kHz, then a small controlled 1dB peak at 10kHz, and a small 'glitch' at 14kHz." "Karma sets new standards for bandwidth integration, and is uncoloured and fast to boot." "Focus, dynamics and projection in the midband are exceptional, but the sound is a little 'clinical', lacking the warmth, romance and depth of smoother sounding high-end models." Klyde ----- Description: moving coil. Replacement for the Asaka but described as "of virtual Troika quality". The Klyde is made by Goldring (to Linn specs) although it is claimed the housings are manufactured by SME. Date of introduction: 1992 Output: 150 micro V Compliance: 10 cu Tracking weight: 1.55 - 1.75 g Loading: >50 ohms Weight: 8.0 g Price: 449 GBP (1994) Troika ------ Description: Top of the range cartridge when introduced. It has a red housing which is machined from high tensile alloy and a three point mounting that only fits the Ittok and Ekos arms. It has flying leads rather than the usual pins for connecting to the arm. A development of the Karma cartridge. Manufactured by Supex, the two were manufactured side by side for a time. "The Troika can be considered to be a variant of the old Karma design. In both of these older cartridges, the magnet and generator assembly was mounted to a plastic sub-chassis, which was in turn bolted to the aluminium outer housing (which was a "U"-shaped extrusion that wrapped around the cartridge internals. The cartridge was capped with a thin, aluminium L-shaped plate that protected the delicate internals." Date of introduction: 1986 Output: 100 micro Volts Compliance: 10 cu Tracking weight: 1.5 - 1.7g Loading: > 10 ohms, nominal 150 ohms, 560 ohms recommended Weight: 7g Price: 546 GBP (1988), 798 GBP (1992) "I track a Troika at 1.6 - 1.7 grams. Higher than this and I get a thick, ploddy sort of emphasis. Less than this and I start to hear mistracking and lack of adequate "orchestral scale"." "I can track the first antiskate test on the test record but buzz a lot on the 2nd and 3rd and fly off on the last one!" "The Troika sounds much better if it is tightened into the headshell until Allen key breaking point." (N.B.this is a figure of speech and is not to be taken literally) What's the difference between a moving magnet and a moving coil cartridge? ------------------------------------------------------------------------- In a moving magnet cartridge (MM) a small magnet is attached to the stylus. It moves relative to a coil built into the cartridge. Because of the size/number of coils the output voltage is relatively high. A moving coil cartridge (MC) has small coils attached to the stylus with magnets built into the cartridge. The coils are electrically connected to the cartridge output pins by fine wires. Because of the need for the coils to be small and light the output voltage is relatively low. Should I use a step up transformer of a high gain preamp with my MC cartridge? ------------------------------------------------------------------------------ "On a side note, regarding the use of step-up transformers for low-output MCs - be sure that the impedance of the transformer is matched to that of the cartridge that you will be using. If the impedance is not matched properly, the frequency response will be audibly and measurably compromised. On other words, don't use a 2 ohm cartridge with a transformer designed for a 40ohm cartridge. Head-amps don't have this problem - at least, not nearly to the same degree. For this reason, and also because of superior bandwidth and phase response, I myself prefer low-noise high-gain headamps or equaliser amps, although a good one can be admittedly fairly pricey." Setup ===== How should I ground the arm? ---------------------------- The standard arm cable has two pairs of signal leads and a ground lead. The ground lead connects the pre-amp at one end and the arm connector at the other. The ground lead should also be split out to connect . The screw nearest the arm connecting the arm board to the sub-chassis and also to the bolt nearest the front of the turntable that holds the metal cross member that holds the power supply and the p clip. How do I "dress" the arm cable? ------------------------------ The cable carrying the signals from the base of the arm to the pre-amp forms part of the turntables suspension, getting the correct position and correctly fixing the arm cable allows the turntable to operate at its best. Before exiting the plinth of the turntable the cable is secured by a p clip. Two points are important here 1) the cable does not and can not touch any part of the turntable between its leaving the arm and the p clip. However it must also be slack enough not to pull the suspension horizontally and must allow it to freely move vertically. 2) the cable should be securely held by the p clip - if you pull the arm cable it should not slip through the p clip. To achieve this get some leverage on the p clip, pulling it tight on the cable while securing it with the nuts. After being secured by the p clip the cable should loop up towards the top plate and then down and sideways to the back of the turntable where it exits via a notch at the bottom of the plinth. How should the spindle be lubricated? ------------------------------------- Setting up the suspension ========================= Preface ------- "One particular potent bit of Linn folklore attaches to the adjustment of the LP12 springs. The legend tells us that the true transcendental LP12 sound only springs forth when the suspension springs have been perfectly adjusted, and that only the best of the best technician priests really know how to do this. Actually the spring adjustment procedure is quite simple. The correct configuration is not that hard to obtain, and not that hard to recognise. Basically, you are trying to get the armboard and platter assembly level with the plinth, centered, and free to move in all directions. To test the suspension, you tap it vertically near the centre of gravity. If a vertical tap causes a smooth vertical oscillation of the entire platter - armboard assembly you are done. If the tap causes irregular motion (the vertical oscillation produces horizontal or rotational modes), then the springs need to be adjusted." Theory ------ The design of the turntable attempts to isolate its parts into two. One part is connected to the real world, the other part is disconnected in an attempt to isolate it so it is unaffected by its environment. The isolated part comprises the sub chassis, bearing, platter, arm, and arm board. The sub chassis is supported from underneath by three springs which are themselves supported by washers which hang on the ends of three bolts attached below the top plate. Thus the isolated part can be affected in three ways, via the springs, via the belt or via the air surrounding it. As the springs support the weight of the platter the set-up of these has the greatest affect on the turntables sound. The LP12 is notorious for being sensitive to how it is set up and once set up physically moving the turntable or the passage of time is likely to degrade the setup. Static setup ------------ In normal operation the turntable should be placed on a level support. To ensure levelness of the support some means of adjusting the levelness is usually necessary. It is therefore a good idea to set up the suspension with the turntable in its usual operating position and begin the setup by levelling the support. Access to the inside of the turntable is necessary during setup and this is gained by removing the base plate. Access is made easier if the turntable is raised in some way, four full drink cans, one at each corner are a convenient means. If the support is level the top of the plinth should also be level. Place the mat on the platter, and an average weight and thickness record on the mat. Use a record that has no value to you (in case its gets damaged). The sub-chassis sits on top of three springs which are held at their bottom by three bolts which then run up the centre of the string to the top plate. Misalignment of this assembly is the commonest source of problems. The top rubber grommets should be centred round the bolt and the sub-chassis should be properly seated on the grommets. To adjust the height and levelness of the sub-chassis, arm board and platter the nuts at the bottom of the suspension bolts are rotated either to raise or lower it. By adjusting the nuts on the suspension bolts by differing amounts the suspension can be levelled. The height should be adjusted so that the arm board is brought level with the plinth and the platter level with the top plate with a gap of about 2-3mm equally all round. Check with a spirit level on the platter. Since the turntable support has been levelled, levelling the platter should result in an equal distance between the platter and the top plate all round. If you notice that the top plate is slightly warped in a downward fashion along the edge adjacent to the armboard, this is normal. The top plate is stressed when fitted into the wooden plinth, for better resonance control, and transmission of unwanted energy. You are now ready to set up the suspension. Rotating the springs affects the horizontal position of the sub-chassis and arm board. The position should be adjusted to centre the arm board in its position within the plinth by rotating the springs. If you have trouble setting up the suspension it may be because the springs are old. The weight supported by each is unequal, the spring nearest the arm has more to support. With time the compression rate of the spring changes upsetting the bounce of the suspension. Consider swapping the most stressed spring with the spring nearest the motor assembly which is the least stressed. Dynamic setup ------------- The dynamic setup of the suspension is tested by bouncing the suspension and observing how they die away. The suspension is set bouncing by pushing down on the platter at the sub-chassis centre of gravity. This point is near the intersection of a line between the spindle and arm pivot and the outside of the inner platter. When excited the suspension should oscillate in a vertical direction only with no horizontal or erratic motions. If there is any tendency for the sub-chassis to move horizontally this should be adjusted out by rotating the springs and their grommets. This works because the springs are not completely symmetrical and have a soft and a hard side. The idea is to have the springs balance each other out. Begin with the spring and grommet on the left of the turntable. Rotate both by 1/8th of a turn until the bounce is a straight as possible. Be sure to rotate both as otherwise you may introduce a twist in the spring which will upset the suspension. Rotating the springs may change the height of the suspension so before adjusting the next spring check the suspension is still level and adjust if necessary. Next adjust the front spring & grommet in the same way and then the rear spring & grommet. When all three springs have been rotated, untwisted and levelled the suspension's bounce may still not be correct and the process may have to be repeated a few times. When complete check there is no twist in the springs, that the suspension can move in all directions without the arm board hitting the plinth and that none of the grommets touch the chassis bolts that passes through it. Finally unload the suspension by removing the outer platter, replacing it and again checking the height, levelness and bounce of the suspension. Setup of the motor ------------------ Having set up the suspension the motor is adjusted to achieve the correct run of the belt round the platter. The tilt of the motor can be changed by adjusting the two screws protruding from the top plate on either side of the motor. Loosening the screw furthest from the bearing and tightening the other tilts the motor towards the platter. Tilting towards the platter causes the belt to run higher on the pulley. It should be set so the belt drops to the bottom of the belt guide. To see this happening, which usually is hidden under the outer platter remove the outer platter and replace it back on the inner platter upside down. When adjusted to your satisfaction the motor screws should not be tight but should not be loose enough to rattle or buzz. Setup of the arm anit-skating force ----------------------------------- Here are some suggested methods of setting the anti-skate force. A good method of setting the arms anti-skating force is to use a test record. These records have a tracking test which uses a 300Hz groove with amplitudes of 22.4 micrometers to 89.6 micrometers in 3db steps. Mistracking shows up as a buzzing sound in one or both channels. Start with the lowest test and try subsequent tests till you hear mistracking in one channel. Then adjust the anti-skating force till the mistracking occurs on both channels equally. Increasing anti-skating force reduces mistracking in the right channel, and decreasing anti-skating reduces mistracking in the left channel. If your cartridge is new repeat the procedire once the casrtridge has broken in. Normally, you will find a significant spread of anti-skating forces which will allow your cartridge to track the high-level groove without distortion. In this case, you should reduce your tracking force until you have found an anti-skating positions which zeros in on a specific null position. Now, you must observe your anti-skating scale and your tracking force scale. If you wish to increase your tracking force, you must increase your anti-skating force by a proportional amount as observed on the scales. This is a much better and more accurate method of adjusting anti-skating, but it is not perfect. The next is a good method to employ if you do not have access to test records. Play a record which actually exhibits some degree of mistracking. If the mistracking occurs in only one channel tweak the anti-skating to see if you can eliminate the mistracking or get it to occur in both channels simultaneous. How do I look after the belt ---------------------------- Clean the belt with a wax-based cleaner such as Pledge or Mr Sheen, which greatly improves torque. Then rub it with talc, remove excess talc and refit it, this provides lubrication and allow slippage at start-up. Also clean the metal surfaces of the drive pulley and inner platter. Use gloved hands to avoid oils and acids from fingers affecting the rubber and aluminium parts. I want to transport my LP12 - how should I pack it? --------------------------------------------------- The simple answer is to repack it to repack it as it was initially packed. You should keep the original packing material for the turntable and the arm. Can my LP12 be upgraded? ======================== Linn have produced a number of upgrades since the LP12 first became available. These can be fitted to bring an old turntable almost up to current specifications. "Actually a 1977 LP12 cannot be upgraded completely to a 1996 spec LP12 for a couple of reasons: The current top plate has an extra chassis bolt welded to it. This torquing chassis bolt is situated in the back left corner of the turntable and runs through the corner brace. It is intended to reduce vibration in the top plate introduced by the motor. The older LP12 plinths do not have the larger corner bracing found in newer tables. The corner braces were introduced to address a problem of splitting glue joints in some climates and to strengthen the plinth overall. In addition, minor things such as the wiring strap, the belt guide, the lock nuts, etc. have changed over time. These are not generally considered when people upgrade their tables, but would add cost if someone wanted all of the parts changed. So in most cases, if someone wants to get a current spec LP12, it is less expensive to buy a second-hand production table, say 1993 on, or be content with upgrading most of the parts and not worrying about the other minor differences. Despite the above reasons an "old" LP12 can be successfully upgraded with newer parts." In addition to upgrading the turntable itself the arm and cartridge can also be upgraded. The possibilities are described below. What upgrades are available for the turntable? ---------------------------------------------- Linn upgrades for the LP12 -------------------------- If the turntable does not already have it you could have the Cirkus kit fitted. The Cirkus kit contains new springs as well as a new bearing, inner platter, armboard, belt etc. For an evaluation of this upgrade look in the Analogue Addicts archive at http://www.york.ac.uk/~mjgw100/warren/0000.html which concludes "The Cirkus kit at gives a bigger improvement to the overall sound quality than the Lingo." "The Cirkus kit primarily replaces the bearing and suspension parts. It does not replace every part in the LP12 that has changed over the years. For example, newer tables have 1) a plinth reinforced with corner braces 2) solid base board 3) motor with factory installed thrust pad 4) top plate with extra torquing bolt 5) 8 mm flex locknuts 6) wiring strap with 4 more screw holes 7) assuming Valhalla, different caps, some component changes, e.g. R1 is now a varistor 8) plastic belt guide 9) M3 x 12mm adjustment screws (larger than older ones)" Solid Base ---------- Description: Replacement baseboard more rigid than original. Price: 35 GBP (1992) Trampolin --------- Description: Replacement baseboard fitted with 4 feet. Its silicone membrane suspension is intended to filter out a specific band of low frequency noise centred on the area just below 50Hz. Said to improve the LP12 when situated in a room with a solid floor or when placed on heavy furniture. Price: 85 GBP (1992) Non Linn Turntable upgrades --------------------------- The Avoldale LP12 upgrade kit ----------------------------- The Russ Andews Torlyte sub-chassis/armboard upgrade (No longer in production). Arm Upgrades ============ Arms themselves usually cannot be upgraded. Usually the entire arm is replaced with a better one. However see the tweaks section for arm tweaking suggestions. Linn Arm Upgrades ----------------- "[Upgrade from an Akito to a] Ittok LVII or LVIII if you can find one. Would cost about the same as new RB300. I've been told that the Rega can be hard to mount on the older chassis LP12's though I'm not positive of details. While the Regas a fine arm I still prefer the Linn Akito over it on the Sondek but that's my taste." If you have an Ittok you could upgrade to ... an Ittok. Here's why! "Ittok came first as LVII, later replaced by LVIII and finally (for a short period) as LVIII/2 with Ekos-type arm-rest (i.e. no hole in the board needed). I'm told that even before LVIII came, Ittok was improved more than once. Visually I've noticed changed weights, more shiny on early ones. The biggest improvement is said to be from LVII to LVIII but I was thinking about swapping my LVII to a LVIII/2 as it was so good. I felt it was better than previous LVIII's I've heard. However I found a second hand Ekos and went for that. If you buy a used LVII check the serial number and try and determine which year it's from as its year should be reflected in its value." Non Linn Arm Upgrades --------------------- "Contrary to many views the Rega RB300 (new one) *can* be fitted and sounds excellent, after that you would have to spend a lot more money for Aro or Ekos." Cartridge Upgrades ================== The unfortunate fact is that the stylus of a cartridge wears out and periodically needs replacement. This enforced change is an obvious time to consider a cartridge upgrade. Can I retip my cartridge? ------------------------- Moving magnet cartridges usually have a removable/replaceable stylus which can be easily replaced. Moving coil cartridges don't have a replaceable stylus but there are a number of people offering to retip / service moving coil cartridges. Belgium: J.A.Allaerts, tel +32.(0)14.657038 or through Hifi Corner +32.(0)3.322.01.11. Netherlands: A.J.Van den Hul, Penhold, tel +31.(0)20.6114957 Switzerland: Benz-Micro, Rheingoldstrasse 50, CH-8212 Neuhausen am Rheinfall, tel +41.(0)53.224545 UK: The Cartridge Man, 88 Southbridge Road, Croydon CR0 1AF. tel: +44 (0)181 688 6565. UK: Expert Stylus Company, PO Box 3, Ashtead, Surrey, KT21 2QD, England tel: +44.(0)1372.276604, fax: +44 (0)1372.276147 USA: Van den Hul agent is Stanalog Audio Imports, P.O. Box 671, Hagaman, NY 12086 tel/fax 518.843.3070 Australia: Audio Dynamics, 155 Camberwell Rd, Hawthorn East Victoria, 3123. Fax +61 3 9813-3108 is preferred, or phone +61 3 9882-0372 "Melbourne Audio Club members liked the Garrott's work. Audio Dynamics, a division of Tivoli HiFi, who have been trading over thirty years and have a good name around Melbourne, Australia, have in fact, taken over the entire business of the Garrotts,with whom hey had dealt over the years. They now do all repairs to cartridges. This includes Koetsus, Benz, van den Hul (the same thing) Sumiko, Deccas, all the previous Garrott MCs, (including the P87). They re-tip Deccas, of course, but they also rebuild Deccas. They even build NEW ones from scratch... just like when there was a Garrott Decca; built from scratch from parts supplied by Decca. They actually a new model P88, a Moving Magnet cartridge. Prices in Australian dollars, 1996) Re-tipping: varied diamond shapes are available; conical, elliptical, Microscanner and Microscanner2 etc. From $130 for MM to $285 for the dearest diamond on a MC. Cantilever repair extra: basic $60. If boron, beryllium, sapphire, diamond... surcharge, $130-$200 extra. Major rebuild. $500-600 dis-assemble, repair, rebuild, listen, tune. Most suspensions can be replaced, a common reason for cartridge retirement. The word is that they still sound true to the original (unlike some re-builds) only better." Upgrading from a K9 Cartridge ----------------------------- "I am still not sure I know what this cartridge (the is Audio Tech ML150 ed) ultimately capable of. But I am getting spectacular results at the moment." "Well faced with the dilemma of whether to replace my K9 stylus at $200 or buy a whole new cart for a bit more $ ($50) I decided to do the latter. After some good input from the list Audio Tech ML150 was a prime candidate as I wanted to stay with MM. I had narrowed it down between the 150 and the Goldring MM's, even considering their Eroica high output MC. But the dealer I bought the cart from who sells both AT and Goldring, after discussing my gear, likes and dislikes, decided the 150 was my best bet. He told me he preferred the 150 to the Goldrings in the same price range. Also since I liked the K9 he stated that it would share some sonic traits with 150 since the K9 is sourced from Audio Tech. The dealer stated that 150 would be more refined and he was right. One thing about the ML150 that impressed me right off is that it sounded good. I know this sounds rather pedestrian but a lot of cartridges can sound pretty nasty until they have a fair amount of play time on them. The 150 at first seemed more laid back and less "pacey" than the K9. On the other hand it seemed to be giving more detail than the Linn cartridge, especially in the midrange. This also led to a realisation that the 150 seemed to deal with record noise even better than the K9. I played some lps that I had bought used that, while enjoyable had some noise that would drive your average digiphile to "fits"! Well the 150 made the noise less obtrusive and the lps more enjoyable. LPs I owned that were quiet to begin with became almost silent in cd like way. The ML150 has a considerably smaller cantilever and stylus than the K9 which seems to allow it to get further down in the groove. On a lot of used and older records it seems to get past some of the wear caused by bigger styli. Also the 150 tracks at 1.5g as opposed to the Linns 1.75g which has to be nicer to the vinyl in the long run. The more delicate stylus assembly made me decide to stop using the Linn green paper for cleaning as it seems to risky. Overall the 150 has a better balance than the and K9 is more detailed. Image depth and space cues are better as it extracts more info from the record. My initial impression that the cartridge was less pacey than the Linn was gone after the 150 broke in. My guess is that the Linn has more emphasis in the uppermids thus giving the impression of more zip. The 150's smooth top and balance don't seem as exciting at first in comparison. Oh and for the record I use a LP12/Valhall/Cirkus/IttokII. I have to say a good cartridge for those of us with Champaign taste ,beer wallets and want to here what a good mm can do for those lps." Power supply Upgrades ===================== You could upgrade the power supply. An external power supply (see the section, "other supplys") would be the ultimate upgrade but a cheaper alternative, if the turntable does not already have it would be the Valhalla board. These turn up used especially from dealers who take them out to install Lingos or Armageddons. DIY Valhalla improvements ------------------------- WARNING: Those considering DIY improvements on Linns Valhalla power supply should be aware that the output of the unit is not isolated from the mains and that all the supply lines to the motor are a number of hundreds of volts above earth. "The Valhalla does not have a well regulated DC supply rail. I got an apparent improvement in sound with an extra RC filter between the rectifier and the on-board caps. A regulated DC supply would probably help it some more. However this doesn't address what is probably the main deficiency of the Valhalla which is the use of a single phase shifting cap on one winding giving much less than a 90 degree shift." "After extensive trials this week with a new motor, it looks like the following mod is effective in reducing motor vibration. NOTE: don't do any measurements with respect to ground, the grey 'zero volt' connection is actually at around 130 volts. BE VERY CAREFUL with the Valhalla circuitry if you do any mods or measuring - it is live all the time the unit is plugged in and carries voltages in excess of 300V! For 60Hz, a 0.20uF cap in series with one winding seems to give the least motor vibration. The measured phase difference is almost exactly 90 degrees. For 50 Hz, 0.22uF appears best. Note that the winding with the cap on shows a higher voltage than the other winding. Adding any dropping resistors, either before the cap to reduce both winding voltages, or after the cap to even voltages on both windings, gives an increase in motor vibration. In addition my Valhalla had the 'Zener Mod' that had been added by my Linn dealer. This consists of two diodes and a resistor added between the grey and blue outputs: ------Z1-----R------Z2------ | | | | Connect to Connect to Grey Wire Blue Wire Terminal Terminal Where R=12K - Looks like a 0.25W Carbon film 0.5W might be safer. Z1 and Z2 are Zener diodes type 1N5266B" DIY "Gedon" ----------- "The transformer in the Naim Armagedon is a 340VA to 110V type. Then comes the little phase shifter after which the output is 79V. The phase shifter consists of a serial resistor to drop the voltage to 79V and two parallel caps in one leg. 31V ---/\/\/\-----+------------- motor 1 | | | +---| |---+--- motor 2 110V 79V | | | | +---| |---+ ---------------------------- motor common The resistor is orange, orange, ? i.e. 33x? Ohm. I measured the current of my Mantra motor (same as in LP12) that was 10mA. So I'd guess the dark third ring is red. => 3.3KOhm (31V / 3.3k = 10mA). The caps are Siemens types MKT. (Siemens MKH) These rectangular green types, where the connecting legs are soldered onto the outside case. Dimensions are 7.5mm leg distance and about 4 mm thick. So lets guess a little bit. My Mantra had a similar circuit (130V to 75V through serial resistor) and then a 220nF cap in series to one motor leg. There are several capacitors that would match from the dimensions side. There is a 220nF 100V type cap with just the right dimensions, But in the Armageddon has two in parallel. There is also a 100nF 250V type which is the same size so that could be the solution." Do It Yourself Power Supply --------------------------- There has been some discussion on the list about power supplys for turntables. Most turntables have an synchronous motor which has two windings (4 wires). An alternating current supply is applied to the windings which forms a rotating magnetic field. The motor's rotor follows the field produced by the stator at the frequency of the supply i.e. the rotor turns at a speed synchronous with the alternating current supply. Most motors require a supply with a voltage less than the voltage available from the mains. The windings also must have supplys of different phase ideally with a 90 degree phase shift. The most basic supply uses combinations of resistors to drop the voltage to acceptable levels and a capacitor to achieve the phase shift. "Suggested values are (given a motor resistance of 8k8 ohms and inductance of 10H). For 240V, 50Hz C1 --------+----||---------------- Blue | R1 +--/\/\/\---+---------- Red 240VAC | = C2 | --------------------+--+------- Grey | +------- Grey R1 = 20k ohms C1 = 0.1uF, C2= 0.1uF, Vout is about 75V For 120V, 60Hz C1 --------+----||---------------- Blue | R1 +--/\/\/\---+---------- Red 120VAC | = C2 | --------------------+--+------- Grey | +------- Grey R1=3k3 ohms, C1=0.2uF, C2=.47uF, Vout is about 85V" What tweaks can I try? ====================== Tweaks are usually relatively minor and reversible changes which can be tried to see if they work. Most are probably system dependent so and may or may not work. Here are some suggestions for you to try. Try using the turntable with the dust cover removed. Either remove the hinges from their housings on the back of the plinth or raise the dust cover and slide it up and back and out of the hinges. "Playing with the lid closed may affect your tracking force, due to static electricity generating forces between arm and lid. An old demo of mine was to wipe the lid with a cloth. Invariably, the Akito levitated and crashed into the lid." Try adjusting the tracking force a few 1/10th of a gram up or down. A good cartridge will most definitely change sound according to the tracking force. In doing so you may also have to change the vertical tracking angle by raising or lowering the arm to compensate. Try a Ringmat. Try a better arm cable. Use some sort of compound between the cartridge and headshell to essentially cement the connection. Suggestions are non-hardening clay, olive oil, "Kilopoise" viscous lubricant. Use some short of material or compound e.g. paper or grease between the inner and outer platters to improve /change the coupling between the two components. Tyr changing the turntables mains plug. "MK plugs work very well but I feel you MUST clean the pins of all the nasty factory lacquer." Put the turntable on its own mains spur, or change the socket it is connected to putting it upstream/downstream of other components. "Having the Lingo plugged as far away as possible from the amps is essential. It does muck up other gear from the rubbish it pumps back out to the mains. A separate spur would be nice....but for those of us who can't arrange this, there is a solution. Get a load of ferrite clamps and put them on the mains lead. I have about 5 on the lead and they seem to have worked wonders." It has also been suggested that the same applies to the Valhalla. Contributors ------------ Alan [email protected], Dave jennifer&david , David N. Barnett, Frank Gales, Gary Fozzard, Hartmut Quaschik, Iain A F Fleming, John Elison, Jonathan Carr, Kalman Rubinson, Ken Hotte, Lance Dow, Larry Muirhead, Leigh Norton, Martin Carrington, Peter Allen, Peter Campbell, Peter Houck, Rob Saggers, Rex [email protected], Stefan Svala, Steven Wallace, Tony Fafoglia, Werner Ogiers. -------------------- End of Analogue Addicts Linn LP12 FAQ. --------------------