The answer all depends on the cartridge, phono stage and step-up in question. There is no universal answer. Is there some particular combos you're looking at?
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My short answer is that some will say that adding another "step" along the way by inserting a setp-up tranny is the wrong approach to good sound, preferring to keep the signal un-adulaterated by not running such a low level signal through miles of secondary wiring...
Iv'e run both ways, and really, each was very satisfying and enjoyable if set up right. Currently I use a MM cart with a MM phono..I dont know if that says something or not??
I use a very good separate phono stage [Blue Circle 707] AND a step up transformer [Bob's Devices]. Why? Because I like the way it sounds. See the review of Bob's in TEN AUDIO. I am a Blue Circle dealer but not connected with Bob's. This is a totally subjective area, there is no "best"; it is what YOU like.
Any argument that a stepup is theoretically inferior because it adds an extra device is simplistic at best, maybe specious. An active MC stage also adds an extra device. The question is, which device works best with any particular cartridge and the following (MM) gain stage?
The answer depends on the individual components.
FWIW, the active MC phono section in my $12K Doshi Alaap outplays my $800 Bent Audio Mu (copper version) stepups, despite fanatical tuning of the Mu's impedance for individual carts. What does this prove? Maybe not much, given the price difference. Still, though I haven't heard every stepup (not even the reportedly better silver Mu) no MC section of any type has ever outplayed the Alaap's IME.
One important fact: impedance matching with stepus is orders of magnitude more critical than with an active MC stage. True afficionados may use both primary side loading (for the cart) and secondary side (Ziebel) loading (to control transformer resonance). Getting all this right in a resolving system can take alot of trial and error work. Impedance setting with an active stage, while certainly audible, tends to be less critical.
Not to complicate an already very complicated matter, but if you have a good MM phono that you are happy with, you can also use one of several "head amps" or pre-preamps" that are available. These are stand alone active gain stages and would be used instead of an SUT. For a time, I used a ZYX (I think its called the CCP-1) and it was very good. There are supposedly 2 advantages of the active gain approach- the first one doug has elaborated on well. The second, actually a corollary of the first, is that an active gain stage (internal or external) is more likely to mate well with more than one LOMC, while its more likely that the SUT approach will require very elaborate tweeking and/or a different SUT for a different cart.
I find that transformers tend to obscure detail and they limit bandwidth. So if you have enough gain, an MC high gain phono section might be better if properly designed.
The loading of the transformer is critical, else it can ring (distort), making things brighter and obscuring detail. All the following is assuming that the transformer is properly loaded:
If you do not have enough output from your cartridge, most phono sections will loose some bass impact. Where a transformer will normally do that too, in this case they will win you some back.
If you have too much noise, the noise will obscure low level detail. Where transformer will also loose detail, it also gets you gain without noise, and so wins you back some of that low level detail.
So- its not something that you can always state what will work in all cases. Usually the manufacturer of the phono section will know if the cartridge you have will need a transformer or not.
If there was a panacea, I would state it but as a manufacturer myself that is well-known for not liking transformers, I'll be the first to admit that they can be very beneficial in a variety of situations!
A low output moving coil cartridge is one half of a "team". The other half is a corresponding coil (matched to the coil in the moving coil (sic...) cartridge of course...) in a step-up transformer. These two units do form a team.
I would never view a LOMC as a "stand alone unit".
The matching and corresponding transformer must be precisely designed to match a certain source impedance and source inductance of the LOMC. Given precise match and technical inspired and executed design, we will look (...IMHO....) at the best possible solution in cartridge based playback.
This is true for LOMCs - medium output or high-output moving coils often do perform better with high-gain active stages. But a very low source impedance (below 6-8 ohms) will always long for a matching inductance more than a matching impedance.
In the end it all comes down - once again... - to precision, minute care and attention to detail.
There are no "universal approach" step-ups out there. There is always ONE matching inductance for a given LOMC.
You will find medium output MC performing to their very best with high gain active phono stages - and you will find LOMCs and ULOMC (ultra low output moving coil) performing their very best with precisely matched step-ups of the highest caliber.
Enjoy the search and the long path of try and error.....
Dear Dertonarm, May I deduce from your statements as follows:those of us who own a,say,'decent' phono-pre but
don't like to mess with SUT's,should choose a cart with +/-
0,4 -0,6 mV? Ie should also not mess with LOMC? I think, for example: Air Tight PC-1,Van den Hul (by ordering what one wants),etc.
Is there some 'critical limit' for those mV values?
A great question and very dependent on a large number of variables, so difficult to say what is "better". I have tried various SUT's and head amps into my Aesthetix IO Sig, primarily to cut down on the tube rush at high gain (you remove some tubes for lower gain in this model).
SUT's generally add a level of dynamic, but can get brittle at the top end very much as Atmasphere describes. With a Koetsu, this can make it sound more alive, but I also agree there is a "ringing" effect that obscures detail. Having said that, in experimenting with loading my beautiful Verity Z, SUT beats, IO alone, Zyx pre pre and Accuphase C-17 and Pathos phono alone.
On my ZYX UNIverse, the ZYX pre beats IO alone, and best is the C-17. In general, my C-17 / IO gives better results, texture, soundstage, depth and believability, than any other combination. However ..... it took a lot of experimenting with IC's between head amp and phono before I got to that point and some cables made this combo the most ordinary sounding of all permutations.
So, I conclude, there is no specific recipe, just lots of trial and error to find the sound that suites your needs and I would argue strongly that there is no quantitative evidence that clearly indicates a preferential choice, notwithstanding personal preferences already noted in this thread by experienced audiophiles, with whom I would never argue with!
This is were the the word "hobby" truly comes into play. I have a SS phono section with both mm and mc outputs. I always felt like the mm was much better than the mc side. So I started doing a lot of reading on SUTs. I obtained a set of transformers from a gentleman on Ebay and built my own.Wow, what a difference!
Yes you have to deal with hum, but there are ways to do that.
The sound is much more dynamic.The sound floor is lower and the frequency response is significantly wider,especially in the treble.The highs seems to have no ceiling.The bass is tighter and more defined.Everything is more coherent.
That said, the transformers I got were good quality Beyerdynamics with values that worked perfectly for my LOMC.
side bar: I emailed Bob of Bob's devices and he offered a lot of help,even though I am not a customer.I cannot say enough good things for a guy that sells a great product and yet is willing to help a DIY project.I would encourage anyone looking into a SUT to try one of Bob's.They start at a very reasonable price and are proven to be excellent.And of course his support is wonderful.
As for which is the way to go? There is no easy answer. I would say that if you are a plug and play guy that doesn't want to spend any time with tinkering with locating the SUT and trying different cables should go with a phono section. But if you are a analog hobbyist than SUTs are a lot more fun and interesting.In my book, a passive device will always have more POTENTIAL than a active one.But active devices are easier.Much like the passive preamp vs. active preamp.
One more thing.I have noticed that a lot of modern tube preamps with phono sections use jfets for the MC section.Many of the reviews of these preamps recieve high praise for everything except the MC jfet section.If you have one of these,a SUT allows for that nice tube phono section to be used instead of the jfet sound.
Dear Nandric, sorry, I missed your question in late november.
Yes, if you want to avoid having to mess (if you strive for the best possibly, you've got to try (i.e.: mess around with...) with SUTs, the safe side is to go for MOMC (medium output moving coil) with 0.5 mV or more.
In general - if perfectly grounded and perfectly shielded (both is easier than widely expected) SUT can be hum free. Take care of the transformers shielding - outer and inner... - and the way it connects to the signal ground and whether the tonearm/armboard/plinth is grounded too.
I still see LOMC with low source impedance and corresponding inductance as one part of an essential team with a matching (impedance/inductance relative to step-up ratio) SUT.
I had my phono stage heavily modded by Bill Thalmann. We decided to go with an EAR MC-4 SUT for the MC gain, so the phono stage is run in MM mode (all tube), bypassing the JFET in the MC portion of the signal path.
The result of SUT + tubes is a much more musical presentation with a lower noise floor. Bill reminded me that CJ's top phono stage has a SUT built-in, so it runs SUT + tubes in the signal path.
For the dollar invested, a "quiet" tube sound with lots of quality and flexibility.
We've specifically avoided using SS input in our tube phono section. Instead, we created the first fully-differential phono stage (1989) as a means to keep noise down. I've tried a variety of SUTs (and never had a hum problem, FWIW).
SUTs do offer a great noise floor, but at a slight loss of detail and musicality. We did everything we could to make sure they were loaded correctly- BTW if not properly loaded the SUT will express the inter-winding capacitance rather than the turns ratio- IOW loading is **essential**. I am sure that with some preamps, the SUT is an important part of getting a LOMC to work, but with our preamps as longs as the cartridge is over 0.2mV going direct sounds better.
Well, I do have a tube phono preamp with total 72 dB phono gain - sans line-stage.....
Nevertheless - I do run my LOMCs with a SUT. I have sufficient gain, but that is not the whole issue. Its not just gain - its the matching impedance AND inductance. Something only the matching SUT can supply for a given low source impedance moving coil.
But after all - that is just my opinion and I do use very low source impedance and output moving coils.
Back in the early 1990ies I too thought that running LOMCs direct into the phono stage is better.
Today I use very special SUTs hand tailored to the cartridges I use.
The LOMC and its matching and corresponding SUT are a team.
And yes - I agree with Atmasphere regarding avoiding ss input stages in tube phono preamps. Tempting as it is (oh, that extra gain...) - the trade off (sonically...) is too high a price. There is no free lunch ......
But in tube phono stages the prime slogan still is: "straight - no cheaser !"
While I have to admit that the JFet tailed hybrid input stages are always tempting from the point of view of a designer.
Yes, I have been told that getting the jfet gain stage to really sound right is not easy, which is why there are many bad examples out there.
I'll leave it to others to sway toward one approach or the other. I am only offering that there is more than one way to get to the music which is why there is a number of great phono stages available and they don't all use the same gain stages. There has to be an equal number of really bad ones of all designs. So, IMO there is no simple answer to the original question. As always, you have to live with/listen to any device for yourself and decide.
May I just say that I find this string to be very informative and fun.It is great having amp designers contributing their ideas and experiences.For someone like myself,being new to the SUT game,it is most enlightening.As I gain experience with my own SUT,the information presented does nothing but help me in my building a SUT.This is not only a hobby,but also a part of my musical life,which is at the core of my life long experiences.Thank you so very much to all.
Yes, there are many ways leading to Rome.
I've walked them all in the past 30 years.
However - there is only one Via Appia leading direct to the Capitol hill (not Washington DC, but ancient Rome, Italia ...) and the Forum Romanum.
You do bring a JFet hybrid phono input stage to superb results. Certainly enough to meet the quality of most any phono stage available on the market in the ears and eyes of most audiophiles and all reviewers.
But the very best phono stages aren't available commercially.
And they can do without the anabolica of JFet-tails.
Let me put one thing straight here from my point of view: it is not about SUT vs high gain phono stage.
These are not competitors in the race for phono gain.
A - precisely matched !! - step-up transformer should be viewed at as one half of the LOMC. Both devices do ask for the other. This is all about matching technical parameters depending on each other.
And doing so to bring out the optimum performance parameters - not because of gain, but because the right SUT provides the optimum working conditions for a LOMC.
And yes, - most LOMCs will work in a high-gain phono stage w/o SUT too. Most good phono stages do provide selectable impedance settings to further accommodate the LOMC. But they can't provide a matching inductance and I think this small factor is sadly neglected in most discussions about phono gain/LOMCs.
This is a very interesting thread. My situation was that a well-regarded, but still relatively modestly priced phono stage with a JFET had been heavily modded. Even then, that left a modestly priced JFET still in the mix. The EAR MC-4 is a flexible, well-built and well-regarded unit. It is is nice complement to my modded phono stage run in MM mode. And yes, it is not purely about gain. I swapped 20 db of JFET for 20 db of SUT.
The use of JFETs + tube or pure tube or SUT + tube, etc. in a well-designed, top-of-the-heap unit, such as CJ, Atma-Sphere, Einstein, Aesthetix, etc. becomes a matter of design and listening preferences.
I like the previous comment that there are many roads to Rome.
Dertonarm, IME LOMCs have a lot of current. So much that if you short them out completely, the sound from the phono section will only be a few db down (and rolled off on top). Most audiophiles don't seem to realize that in exchange for low output voltage you get high current.
If there is any advantage to using an SUT, it is this fact, although a direct-coupled input stage can take advantage of this as well. I suspect that 20 years from now this will still be a debate, and still largely be dependent on the topology of the phono section.
Ralph, your statement on lomc voltage and current is profound. Indeed it is the very essence of how SUTs work.
If only I knew more about the basic concepts of current,voltage,impedance,capacitance and the laws that govern them.Having no background in electronics other than it can kill you I am somewhat in the dark. Having built a SUT I am experiencing the results and consequences of those laws.
This is giving me a taste of the concept of matching and summitry.I really would like to learn more.Keep up the good posts.
To anyone: My SUT default load is 200ohms.Can I load it even lower? It seems to be working very well with my lomc (a Benz Gold)but sometimes vocals seem very slightly strident. When words end in S,it some times sounds like snakes.This is not consistent.
One other thing I am experiencing:If I have a non-shielded interconnect plugged into the preamp I get hum.If I unplug the interconnect the hum is gone.Any suggestions?
Emorrisiv, sounds like you have a grounding problem. Make sure the arm ground, transformer ground and cable shields are all good. You can tie the arm ground to the SUT ground at the SUT's input and that should be consistent with the ground at the output of the SUT.
There could be a loading issue, but I would not mess with it until you have the hum problem fixed! If the ground is not right there could be ringing in the cable (anyone how has worked with oscilloscope probes knows what I am talking about); IOW the hum and the sibilance could be related.
Thanks Ralph, I have been playing with different ground solutions.I have installed a ground plug on the SUT and it really didn't make any difference. I think it would be best if I had a very short cable from the tonearm to the SUT.
The present tonearm cable is very long (1.5 meter).I could just cut the cable and resolder the RCAs.
I also built a short cable which is shielded and I have the shield ground connected at one end only.This cable goes from the SUT output to the phono section.This really helped the sound,taking alot of the snakes out and cleaning things up in general. It really is crying out for a good tube preamp/mm section.
I am in search of a 5 din DIN connector for the tonearm. I know that Cardas makes them but at $50.00 seems pricey.(unemployment stinks!).They also make DIN to RCA connector boxs which are stupid expensive ($250.00) for what they are.
I may have to just chunk down for it anyway.
Can you offer advice on making this cable?
What kind of wire to use ? Do you solder or use leads for the DIN connector? I was also thinking of wiring the tonearm right to the SUT without using a extra cable.
This is a very interesting project. Since I don't listen to CDs much,I have just kept it unplugged from the Preamp and then the SUT is very quiet.
As for the loading.The SUT default load is 200ohm so that is pretty low and right at the low end of the recommended setting by Benz. The snakes from the Ss in vocals is not consistent and I think it is a matter of the recording microphone. The sound is articulate but not strident shows some warmth with nice mids and bass with trebles that can sparkle.
Thanks for the help.
If you are getting sibilance you need to look at why. I guarantee its not on the records. You could be having RF problems- that is in keeping with sibilance and hum BTW.
We always solder the DIN connections when we build a phono cable. My advice: be very careful!
The ground scenario I outlined previously will be fairly resistant to RF BTW.
Emorrisiv, It sounds like you are aware of Michael Percy Audio. If not, go to his site under that name. He does carry the Cardas DIN plug (for less than $50), but as I recall he carries other brands that cost less. Vampire and Neutrix are always cost-effective choices in the connector world. Then I would recommend you to choose some XLO copper wire, 26ga or thinner, for the wiring. It's excellent and "cheap" as audiophile wire goes. Vampire wire would be good too. (I use his 26ga silver wire with cotton insulation, if you want to spend more dough. Sounds fantastic.) He also has braided shield. I think you can get all the stuff you need to make a very high quality IC for under $75, if you choose well.
Amazing! I called Michael Percy and ordered the Cardas plug and the XLO(30guage) wire,before reading the last 2 posts! Great minds think a like! I plan on building the phono cable to be as short as possible.Maybe velcroing/screwing the SUT to the back of the TT.I was also thinking of wiring it directly to the SUT without using RCA connectors.Please tell me what you think of these ideas.They are not set in stone.
I have fixed the sibilants problem. I have a very cheap NAD PP2 phono section.The "stock" load for the MC side was 100ohms. I found the resistors and changed them out several times before arriving at 470ohms.This was BEFORE I built the SUT.I didn't think that the different load would effect the mm side of the phono section.I then tried changing it back to 100 ohm and boy does it sound much better now. No more snakes!The sound is starting to be scarey good.Too good for the money not spent.
I can only think that the additional loading either added or multiplied the mm impedance on the mm side.
I can't thank you guys enough for the lively discussion of ideas and also the suggestions.This is the kind of stuff that makes this hobby great.
In 2003 I started to use a Kondo KSL transformer with my LOMCs. In Germany not many people were using SUTs at that time, it wasn`t really popular. In the beginning I was not really happy with the MC output of the Lamm Lp2 DeLuxe, so I tried the MM with the KSL - and vroom, usally at 3 Ohm, only the Kondo IO-j at 1 Ohm.
Now I have 4 KSLs serving 2 Kondo M7 phonos and another SUT serving the Lamm which is rebuild now and has better and bigger Jensens. Only Boulder and Zanden phonos I use without SUTs. I will never abandon my transformers.
Oddly enough when I changed to the 100ohm resistors the hum problem when I had another cable plugged into the pre disappeared. Just dumb luck but I will take it.I still plan on building a short cable from the tonearm to the SUT.Just waiting on the stuff from Michael Percy to arrive.
these trannys rock!
I have constructed the new tonearm cable using a Cardas DIN plug and .28guage XLO triple shielded wire.It is less than .5 meter long.The wire fit perfectly in the DIN plug.
The sound: Sound floor is lower.High transients are more apparent.Bass seems softer and smoother,it is still there but with less authority.Hum is no longer a issue at all.Sound stage is significantly wider and deeper.Voices have significantly more texture. Strings sound more wooden and organic.
I think that this is a winner.Considering that it is brand new without any burn in,I have to think it will get better and better.
I also think that it will take a VERY long time for the cable to burn in. Does anyone have a idea how long I should expect this to be?
DIY analog: nothing but fun.
DIY SAMA project is next.
Thanks Ralph. I assume you mean not to move it or even touch it? If I left the system turned on,even though there is nothing playing on the TT, would this help in the break in?
Once again, thanks for all the great advice and knowledge base.
side bar for Atmos: Would your big OTL work with my Acoustats?
Yes- don't move the wire. It only breaks in with a signal though it. There are break-in boxes made for that that can speed things up.
We have a number of customers using Acoustats. I've heard a few of them with our amps over the years. They are not hard to drive but some of them have very low impedance, so depending on the model, you may need to use a set of ZEROs http://www.zeroimpedance.com
In one system that I was very familiar with, the Acoustats were so low impedance that the ZEROs were needed for the Audio Research that the guy owned, IOW the ARC would not drive the speaker right even on the 4-ohm tap. The ZEROs can be a real problem solver!
Thanks guys for the advice. I have the Acoustat model 2 which has a nominal load of 6ohms.
From what I have read of the Atmos 140watt OTLs it sounds like what I want when I go back to work. I would love to hear them. Whatever I get it, is going to be tubes.
This recession s__ks!
I have read about the zero's but never heard them.Do they have much of a sonic signature? I imagine since they are passive it is minimal.
I use Paul's speaker cables and they are great.I love the fact that you can but first class sounding cables that don't cost more than a amplifier.I think the cable business could be the death of the hobby.Cables and Stones=snake oil.
Not that I don't believe that cables can make a difference,quite the contrary.But the margin on some of the stuff out there is grossly disgusting.Paul offers great sounding products for very reasonable prices.
The other cables I use are Mike Morrow's interconnects.These cables are terrific! If you have not heard them you should. And very reasonable.
Discalimer: Mike is a friend and in our club.
Once again, I can't thank you pros enough.My DIY projects have really come along nicely.And you guys and others have been a big help.
After a week of playing a lot of records (the best part about unemployment) the cable is starting to sound much better.
With that I have made a newer one.
My friend Mike Morrow gave me some mil-spec. 30ga. silver solid wire, which I have just made a new cable of.
Right out of the gate it blew the Cardas in the weeds!
smoother,more refined,nuanced, lower sound floor, much more and tighter bass. I can only imagine how it will sound after burn in.
more DIY fun
Sorry to go one about this but it is too incredible.
I just rewired my SUT with the same mil-spec. silver solid wire. My system just took a huge leap upwards! The sound stage is much more articulated with less hash and congestion. The bass is much more authoritative and controlled. The trebles are sweet and without glare of any kind. Just sweet.
The sound floor has dropped out of site. The hum problem is gone completely.This wire is amazing. I should find a giant spool of it and go into business.
Emorrisiv, one thing you will find in working with cartridges in general is it is best to keep your connections between the cartridge and the preamp to a minimum.
In the case of an SUT, I think you will also find the cable **after** the SUT to more critical than the one before, as the impedances involved are much higher at the output of the SUT and so more susceptible to cable issues. By comparison, the cable from the cartridge (if the cartridge is properly loaded) is relatively non-critical, especially if you run it balanced, which is possible if you have an SUT.