Triplanar RCA out to Balanced out for MP-1


Hello all, especially Doug Deacon

Well,,,,,, my Atma-Sphere MP-1 mklll has just arrived. much joy. Now I need to reterminate my RCA out from the Triplanar to a balanced out.

I am a competent solderer.

All suggestions and hints welcome
cousinbillyl
have you called Tri Mai at Triplanar to see if it would be easier to have him change the connectors?

Congratulations on the great new Pre-amp!
I can change them easily myself.

What are the best connectors for me to use?.

Do I want gold plated?, etc.

Specifically: which pin is 1, 2, 3?.

Which colour goes to which pin?.
I have made this change. It requires more than just changing the connector.
Check with Tri Mai as suggested. He will provide the procedure to make the change correctly.
Dear Cousinbilly1: My advise is that you buy Neutrik connectors where you will use Pin 2 for ( + ), Pin 3 ( - ), Pin 1 disconnected and the cable shield to the Neutrik " ground " pin ( other than 1,2 and 3 ).

Regards and enjoy the music.
raul.
Raul is correct. I would just add that the wire going to the "ground" side of the RCA plug is the one that should be soldered to pin3. Pin 2 gets the "hot" wire. You can do it yourself, but since Tri is colleagial with Atma-sphere, I am sure he would do it for you, too. I own both a Triplanar and an MP1 myself. I think you will be very happy with that combination and the "right" phono cartridge.
Convention for a balanced connection:

Pin-1: shield (balanced signal ground)
Pin-2: positive signal
Pin-3: negative signal

You have two options:

1. Run single ended into your balanced system as stated the posts above:

Pin-1: jumper to Pin-3 (connect RCA ground to balanced ground)
Pin-2: connect your positive RCA wire
Pin-3: connect your negative RCA wire

2. Create a balanced connection. This has been the subject of heated discussion over the past 12 months. From your perspective, you could care less. I'd try to take this approach.

Pin-1: find a tonearm chassis ground point and connect it to pin-1.
Pin-2: connect to your positive RCA wire (as above)
Pin-3: connect to your negative RCA wire (as above)

Comments on running balanced on the Atma-Sphere site:

http://www.atma-sphere.com/support/se.html

Strictly speaking, Ralph mentions only line level sources in detail in the first paragraph - assuming your tonearm manufacturer will wire your tonearm cable for you. The same principles apply from a wiring perspective for a tonearm - save the discussion on whether or not a cartridge is balanced or floating single ended. For your purposes, you don't care. It's the sound you're after, so wire up in balanced mode and have at it.

Cheers,
Thom @ Galibier
Dear Cousin: You don't have to " find " anything ( like Tom say ), everything you need for a proper balanced connection is on the Neutrik connector and your cable.

Regards and enjoy the music.
Raul.
Dear Thom, I've been thinking that your scheme #1 for hookup is the way you'd do it if a cartridge really had a hot and ground side, i.e., the way to do it if you were to hookup a single-ended CD player to a balanced input preamp. Scheme #2 is the "only way to go", in my view. In fact, in my case I just hook up the tonearm cable shield to pin 1. This works fine with the MP1.
Hi Raul,

By "finding" something, I was referring to establishing electrical continuity between pin-1 and the metal on the tonearm.

If you're lucky and the tonearm cable has a shield which has electrical continuity to the tonearm's body, all is well. I think this is what you're assuming, and in most cases it should be the situation you'll encounter.

Tonearm cables are almost always shielded. Still, I would verify electrical continuity with the tonearm's body just to make sure.

An alternative would be to use the ground wire for this purpose - splitting it into a "Y" to run to the pin-1 of both left and right connector.

Cheers,
Thom @ Galibier
Thank you all.

I have built enough RCA cables to be proficient at that, but, balanced is a whole new ball game, especially coming from the tonearm. I think sending the tonearm back would be best.

I will likely buy some balanced cables here on Audiogon. I am leaning towards the Acoustic Zen Silver Reference ll, any comments or recommendations?.

I will now position my MA-1 Silver amps behind the speakers, but will need to build my own balanced cables. I already have DH Labs BL-Ag shielded cable, and Vampire gold plated balanced connectors. Should both lengths be equal, or can one cable be longer. Any comments?.

Tom, thank you for joining us. I once had a Teres 360 (very few made), it was too soft for me, so I sold it. Next year I will be looking at a new table (presently using a J.A. Michell Gyrodec, highly modified), chances are the new table will be one of your incarnations. This year I have purchased the Tri, a Universe copper, and now the Atma-Sphere MP-1, budget spent.

Raul, I have always enjoyed your points of view, you hold nothing back, your as anal as I am, LOL.

Do any of you know Frank Schroeder personally?. When I purchased my Teres, the DPS that came with it was broken (string). I sent it back, 4 years ago, and have still not received it back. If you could put in a good word for me, that would be much appreciated.

Next weekend I am going to Montreal. Am hoping to hear the new Tenor amp, just a wee bit out of my price range, but still excited.

Bill
Hi Bill,

Contact me through the contact button on my website. I'll get with Frank on your DPS.

He and I will hook up at the Rocky Mountain Audiofest in 3 weeks (drop on by suite 1130 if you're attending).

I haven't spoken with Frank in a few weeks, but typically he leaves early for the Rocky Mountain Audiofest in order to take in some of our beautiful Autumn weather.

I can't make any commitments, but there's an outside shot that I could "encourage" him to pack your repaired arm in his suitcase.

Cheers,
Thom @ Galibier
Hi Raul,

Yes, I was trying to keep my answer general (not specific to the Triplanar) to help expand on the good advice you gave.

With respect to the Triplanar, I have not opened up the junction box that is positioned 2/3 of the length down the tonearm interconnect. This is where the wire separates into left and right channels.

Someone told me that you can pick up the chassis ground from inside this box (to connect to pin-1). Someone else said that only (+) and (-) (pins 2 and 3) are accessible inside this small box.

I'll make a point of checking this in the next few days (swamped at the moment).

Cheers,
Thom @ Galibier
I have a seperate ground wire coming from this box. It could have been spliced to offer two length's?, I think.

This is a moot point since I have now spoken with Mr. Mai, and he will gladly do the mod for a minor fee.
Cousinbilly, I gather your Triplanar has the optional external junction box with the standard female RCA receptacles. This allows you (or forces you) to use additional phono cables from the junction box to the preamp. Since you have decided to send it back to Tri, I encourage you to consider having him remove the junction box in favor of cables that go directly from the cartridge to your preamp inputs. Said cables would be terminated with male XLR connectors, of course. I think this is advantageous with low output phono cartridges, the likes of which you will be using.
Hello Lewm, I had to read your post twice. I have the newest version of the Tri. After the junction box, we now have two shielded cables coming out. Each one is fitted with the Male RCA. I realise there may have been a time when seperate cables where needed. This is no longer the case. The tonearm connects directly to the pre or phono pre (while I was using the Tom evans groove). No extra cables needed.

I have reread the previous posts. I now see why there where a few different ideas. Some people did not realise the cable is already terminated with male.

The installation of balanced cable ends would not be difficult at all. The only dilema I am faced with is I have no shrink wrap. This makes the installation look less professional.
Triplanars come in two basic terminations:

1. Hardwired from cartrdige lead to connectors (either RCA or XLR).

In this configuration about 2.5 feet of cable runs inside a single braided sheath between the tonearm and a small rectangular box. This sheath carries both channels. The other side of the box feeds two braided cables - one for each channel, terminated in either RCA's or XLR's.

The question I was addressing is what's inside of this box - is there access to the tonearm's chassis ground.

As I mentioned earlier, any wire that connects you to the tonearm's metal components will do (for a pin-1 connection), but it's obviously preferable for there to be a cable shield which is tied to the tonearm - to run this to pin-1.

2. Hardwired from cartridge lead to a junction box with female RCA's - requiring an extra set of interconnects to run to your phono stage. This is *not* recommended because (a) you have an extra connection which degrades the sound, and (b) the Discoverey Cable Tri uses is outstanding.

Cheers,
Thom @ Galibier
Hi Cousinbilly, all ...

Well, I just received delivery of my Atma-Sphere MP-1, and made the balanced conversion on my Tri-Planar tonearm yesterday.

I documented the process with photos and procedural hints in this web page in the Tri-Planar section of my website:

http://www.galibierdesign.com/prd_triplanar_xlr_build.html

The photographic quality is only o.k., but it gets the point across.

Note, that since the ground is common to both channels, you need solder pin-1 to the braided shield connection in only one channel.

I opted to solder the pin-1 connections in both channels and risk a ground loop. My reasoning was, that I could recover gracefully by lifting the connection to one of the shield connections inside the black junction box.

Inside the junction box, you'll find three wires soldered together: (a) the black ground wire used for single ended operation (b) and two yellow wires - with one going to the shield of each channel.

Strictly speaking, you don't have to open up the black junction box to do this job. You can clip off the black ground wire flush with the outside of the box and be done with it (or, alternatively leave it hanging free).

I tidied up the installation and made it more reversible by pulling the black ground wire back into the junction box, coiling it up, and tucking it into the box.

As an aside, your MP-1 will sound a bit soft (Ralph calls it "dead") for the first 20 hours, so don't let this alarm you.

I was a bit surprised that any metal film resistor (Caddock upgrade) along with Teflon capacitor (V-cap upgrade) could start out life sounding soft.

Ralph tells me that while many Caddocks have the characteristic "tizzy" signature common to metal films, these particular Caddocks do not.

Enough about the MP-1, this thread is about conversion of the Tri-Planar for balanced operation. Back to our regularly scheduled programming ...

Cheers,
Thom @ Galibier
 
Nice job on the step-by-step documentation Thom - the pictures considerably add to the explanation. Thanks for taking the time to create it.

My MP-1 took roughly 120hrs to flesh out the full measure of harmonics it is capable of delivering. The V-Caps take a while. After its had enough break-in time for you to gauge, I'd be interested in your take.
 
Tim
 
For many it is confusing,seeing that the cartridge outputs are referred to as pos/neg.The real situation is that the "pos" is non-inverted and the "neg" is inverted.Using the tonearm ground as the XLR "ground",usually paralleling the tonearm ground to the two XLR jacks.
With the grounds set up in this manner, there is no chance of a ground loop.
Hi Tim,

Well, I know where the MP-1 is going to end up - having lived with one for 3 days in my home away from home, at the Rocky Mountain Audiofest in October. The only new component in the system was the Classic Audio T-3 (field coil) speakers.

About 36 hours into the break-in (see below for my accelerated process), my guess would be that you and Ralph are dead-on about the 120 hour number.

Break-in is normally an asymptotic process - with the first quarter or so yielding the vast majority of the change, but with subtle yet significant improvements occurring over the remaining period.

I think it's inappropriate for a manufacturer/dealer to "review" a component that we carry, as our motives should be treated as suspect. You need to be wary of false prophets ... and false profits ;-)

At the same time however, I think it's safe to say that the bulk of manufacturers and dealers inhabiting this forum are motivated by their vision of musical reproduction. While we may occasionally step over the line of propriety, it comes from a passionate desire to spread our individual view of the gospel.

I am comfortable however in talking about the break-in process of the MP-1, and a good deal of this can be generalized about the break-in of other components.

It's important to remember that the system profile of an owner purchasing an MP-1 or other expensive product is that they're likely to have a highly resolving system. They will set the bar quite high for any "stranger" introduced into their system. Because of this, injecting an un-broken in component into their signal chain is likely to result in initial ambivalence - assuming the remainder of their system is reasonably optimized and fully broken in.

On Tuesday night, I began my interconnect re-wiring project - converting a single ended interconnect to an XLR terminated output in order to run my see-dee player through the balanced inputs.

This allowed me to accelerate the burn-in process by employing a burn-in track along with my Hagerman inverse RIAA circuit. This handy device drops the signal by 40dB and puts an inverse RIAA equalization on the signal as well. It allows you to run a CD player signal through your phono stage, and if you like, to listen to tunes.

I ran the burn-in signal through the phono stage as follows:

CD player --> Hagerman Inverse RIAA --> Phono input --> Preamp Main Out --> Power amps

A few explanatory and cautionary notes are in order (Ralph can comment if I've missed anything obvious):

1. The 40dB drop of the Hagerman inverse RIAA is fine for an MM level phono stage. Dropping a 2 Volt CD signal by 40dB will result in a 20mv output feeding the phono stage. This is about 4-5 times the normal MM cartridge output - well within the overload margin of any competently designed MM phono stage. The MP-1's overload spec is 250 mV, BTW so your o.k. running it here as well.

2. With the MP-1's 60dB of phono stage gain, the resulting output would be VERY loud if you were to play this signal through your loudspeakers, so beware.

3. When burning in as above, remove any loading resistors from the phono stage. They might unnecessarily challenge your CD player. It's safest to present a 47K input impedance to your CD player.

4. Be sure that the phono source is selected.

5. The amplifiers do not have to be powered on. They will show their grid resistor load pair (100K) to the preamp output, so current flows through the system without the power amps being powered on.

This first 36 hour period has resulted in substantial changes to / improvements in the MP-1's character. With the Christmas rush and such, I did not take an intermediate checkpoint between the 6 and 36 hour point.

At 36 hours, the top end really began to open up - to the point where (when plugging my analog rig back in), I started to think about loading resistors. For the first 5-6 hours, my XV-1s was running wide open (47K load) and still sounded closed in. Now, we're approaching where they'll end up - needing a load somewhere in the 50-150 ohm range.

Whether it's the V-Caps, the Caddocks, the wire, or everything isn't all that relevant to me, but the character of the break-in reminds me of a cartridge I'd like to have back in my quiver some day - the Ortofon SPU Royal-N.

This cartridge had a break-in process that many do, but to an extreme. It took a while for this cartridge to connect the dots and to speak with a single voice. A point in time arrived (about 24-30 hours in) where the frequency bands no longer seemed disjointed, the cartridge sang with a single voice and the magic flowed.

I've heard the break in process of V-caps described as a cyclical series of improvements and disappointments, before everything gels into a coherent sonic whole. This (connecting the dots) may well be what these individuals are describing.

Well, at 36 hours (last night's checkpoint) the dots are beginning to connect - like hands outstretched which are trying to touch each other. They're not quite there yet, but it's tantalizingly close. I'm noticing a slight suckout in the midrange. The bass is extraordinary - both in power and more importantly in texture - being extremely tactile and "fleshy" which is a direct result of the top end filling in (bass texture comes from extended treble).

I'll report back next week ...

Cheers,
Thom @ Galibier
Hi Tpsonic,

I feel a bit uncomfortable talking about the MP-1 in a "review" context, since I sell Atma-Sphere, but in the next 10-14 days, I'll set up an Atma-Sphere section on my forum and I'll comment about it in detail over there.

I think break-in is a legitimate topic to cover here, and I'd be interested to hear the experiences of owners of the Essential and the Doshi as far as break-in is concerned.

I'm about 450 hours into the process, and I still sense subtle changes having occurred since my last checkpoint.

I'd agree that in some systems, one could be convinced that break-in is complete at about 120 hours. It's at about this point that the MP-1 becomes very enjoyable, but It's very clear to me that it's still changing and improving like a fine wine.

The first 20 hours were shut in and dead sounding as previously reported, and from hours 20 through 100, the MP-1 swung back and forth over the "neutral" line from sounding restrained to slightly agressive.

This "swinging" is not all that unusual a break-in phenomenon.

In the 120 hour range, the MP-1 begins to show its pedigree.

There's a fairly good review of the MP-1 over here:

http://www.soundstage.com/revequip/atmasphere_mp1iii.htm

The reviewer likens the break-in process to one of a flower blooming, but the sad part of it is, that as much as he fell in love with it, he was not experiencing an MP-1 in full bloom if he thought he was done at 120 hours.

200 hours brought further refinement. At that point, I began traveling 4 days/week, so my subsequent timeline has been in in approximately 120 hour chunks as I continued to avail myself of the Hagerman inverse RIAA and a burn-in CD.

With my next "visit" home (the 320 hour point), solidity of presentation, subtlety, and nuance continued to improve, and I was getting more than hints of what this unit is capable of.

In my current "visit" home, I'm at the 450 hour point and I sense some subtle yet significant improvements since last week - all the normal things you'd expect - improvements in delicacy, space presentation, base solidity and harmonic development, etc.

I'm not prepared to say that we're done yet. I'll spend considerable time this weekend bonding with it while I work on some turntable builds. I'm very interested in hearing how it changes over the next 50 hours (continuing to run the Hagerman inverse RIAA through it while not listening).

If I were a betting man, I'd say that as good as it sounds now, we're not quite done yet. I get a sense of an asymptotic process going on here.

As an aside, cartridge loading (XV-1s) is in the 50-70 ohm range. This is within the range I'd expect. While most of my experience with the XV-1s has been in the 100-150 ohm range, this was when employing step-up transformers, so all bets are off. I've heard for example, extremely musical implementations of the XV-1s where it has been loaded as low as 35 ohms.

I'll file an update at the end of the weekend or early next week.

Cheers,
Thom @ Galibier
An interesting thing about break-in - especially if you've never heard the gear before - is gauging when it is complete. How long does one go without hearing changes before assessing break-in is finished? If one knows a fully broken-in piece, then its easier to gauge a unit has not yet met the known expectation. There's also the question of relative change across time. My experience with the MP-1 found the majority of change in the first 120 hours and I agree that further changes occurs after that, tho not, imo, to the same degree (however one measures that!).

Likewise, being away from listening in chunks of hours while break-in continues to run may better lend to hearing changes across those hours than continuous exposure for the same period. Re-acquaintance and one's sonic memory may also play a role in the perception of change.

Wrt loading, the MP-1 is a wonderful instrument for hearing differences in load resistors.

Rgds,
Tim
 
Hope you don't mind me asking how you like your Mp-1 MK3? How is the line stage?
Hi all, I am reluctant to mess with the fine made RCA connectors by Tri but I like to try 'balanced' because I
own the Basis Exclusive with both possibilitys. So there is
the shield on both (L&R) sides. The advice is to connect the shield to the pin 1. But there is also a separate ground wire. The question: is the shield connected to the arm-mass? If so what to do with the ground-wire?

Regards,
The turntable/arm ground wire should be used as the XLR ground.The +/non-inverted and the -/inverted signal will go to the respective terminals on the XLR,as these are floating +/-.
Hi Nandric, tie the ground connection of the arm to pin 1 of the XLR. If the shield has 2 conductors inside, then the shield will tie to pin 1 of the XLR also. That way you get a proper balanced connection from the arm to the preamp.
Dear Atmashere and Tpsonic, I am thankful for the advice but,alas,I am not capable to move in the opposite direction at the same time. Something that according to physics and logic is not possible. So I still have no idea
what to connect to pin 1: according to Atmasphere both(the shield as well as the ground wire);according to Tpsonic only the ground wire. But I still dont know which of all
are connected to the arm-mass.The shield or the ground-wire or both? Then,you see,I will know what to connect to
pin 1.
BTW I think I should look for a different hobby.

Regards,
Nandric, Try it both ways and see what happens. The very worst that can happen is hum; no risk of damage to anything except maybe your speakers if the volume is turned up too high. I own a Triplanar which I converted to XLR jacks from RCA jacks. I connected the shield to pin1. (I presume you know that hot from the RCA jack goes to pin2 and ground from the RCA jack goes to pin3.) I did not connect the tonearm ground wire to anything. It just hangs in the breeze. There is no hum. I've been using it this way for several years and with two or three different cartridges. If you DO get hum, just revise the ground connections, and you are likely to defeat the problem.

Interestingly, I converted my RS-A1 tonearm to straight thru balanced connection, for use with my MP1. I eliminated the female RCAs at the base of the tonearm and ran about 3 feet of Cardas wire straight from the cartridge pins to the preamp with XLR jacks. Once again, I connected the shield to pin1, but in this case I did have a hum problem which was eliminated when I grounded the body of the RS-A1 to the MP1 chassis.
Dear Lewm,Not everyone is as fearless as you are.But if I blow up my loudspeakers (those are my 'babys') I will kill myself or be killed by flying pieces of beryllium.I own the
Usher BE-20. So this hobby of my is literally toxic and, regarding my bank-account,also insane.
But if your Triplanar is also 'model' VII then I know what to do.
'Interesting',to use your expression,the former model VI(?)
has visible shield connection with the arm-mass.
Thanks and regards,
Nandric,
If you are unwilling to attempt a rewire and intend to keep the components you now have (I'm a happy AtmaSphere MA-1 amp owner and LOVE the sound!), I suggest you contact Albert at Space Tech Labs about adding one of his tube buffer/RCA-balanced converters.
My phono stage is single ended in/out. As well, the turntable and phono stage are both on a side wall stand, 10 feet from my line stage. The line stage is balanced in/out for best use with the Atma amps.
I bought Albert's "BUF-101", which is both buffer and RCA-balanced converter, as I have many spares of the tubes it uses (6X5 and 6L6).
Bottom line: I connect a 0.5m RCA pair from phono stage to the "BUF-101" RCA input, and use a 4m balanced (Mogami) cable pair into my line stage. The "BUF-101" is sonically transparent and I have no hum, despite the long XLR cable run that crosses several power cables en route to the line stage. I'd previously tried RCA-XLR adapters - hum city! I love the way my analog source now sounds.
The "BUF-101" costs a bit over $500USD and Albert may may recommend a less expensive of his converters for your particular application/gear.
This option only puts a bit of cash at risk.
Just my 2 cents...
Nandric, You made me think. The shield for the Triplanar tonearm wires contacts the tonearm body where via the clamp at the base of the mount. So in effect, the shield per se grounds the tonearm body to the preamp. This may be why I never needed to attach the tonearm ground wire to anything. Conversely, I isolated the phono wire shield from the RS-A1 body, where the wires exit thru the holes formerly occupied by the RCA jacks. This may be why I needed to create a separate ground between RS-A1 and MP1. By the way, the hum that I did have with the RS-A1 was annoying but very benign. Not at all capable of damaging a speaker. Moreover, the frequency of hum is way below anything seen by your beryllium tweeter. Fear not.
Dear Lewm, You underrate my Usher BE-20 because they also
'possess' an beryllium 'mid-speaker' and not only.as you suggest, the tweeter. I payd 17.000 Euro for the 'babys' and want everyone to know. According to me you own the
'old' Triplanar VI(?) because I also had this 'model' and
know about the 'shield-connection' to the arm-mass. But because you are in the USA and I in Europa I am not scare of you. Sadly I am not totaly sure about that.In any case I will not mess with the ground-wire because I have bad experience with connection to the pre-ground.
But I was more scared by the proposal of Jb0194. Say 'adding up' solution. I own Emitter II Exclusive + Basis Exclusive + transformers + batterys. In my living-space there is a kind of German artillery situated and I
really think that I have some right for some space for myself. So sorry Jb0194. I know you mean well but there are
limits even for an HI-FI nuts.

Regards,
Lewm and Nandric, this is why I recommend that the tone arm ground wire and the shield both be tied to pin 1 of the XLR. No hum problems! I have even used Kimber wire between the arm and preamp (using an SME V, not a Triplanar) and no hum at all.

A phono cartridge is a naturally balanced source and does not need a special circuit to convert it to balanced operation- just the right hookup.

Nandric, Obviously you need to be comfortable with whatever you do, but I guarantee the hum associated with poor grounding of the tonearm will not hurt your speakers. It's 100Hz or below in frequency; even the midrange is not involved. Moreover, it is low level at normal listening levels, e.g., I was able to listen to and enjoy the RS-A1, hum and all, before I fixed the problem. Congratulations on your expensive speakers, however, and I do understand your desire to avoid damaging them. My Triplanar is about 15 years old, but Herb Papier, the original inventor and manufacturer, upgraded it to VII status as one of his last acts prior to selling the company to Tri Mai. In fact, Tri was visiting Herb to learn the art, when Herb did the last upgrade. I am not aware that there was any difference in grounding the shield or not grounding it at the tonearm side among various versions of the Triplanar. But you may be correct in that inference. Anyway, this is a simple fix.
BTW, My assumption that your hum will be 100hz or below is based on my guess that you live somewhere that has 50 Hz mains frequency. The hum will be at 100 Hz or at 50 Hz, depending upon the rectification of your amplifier. If you live with 60 Hz mains, then hum is at 60Hz or 120Hz.
Dear Lewn, You are right,as usual,but this time on logical
ground: if the assumptions are 'wrong' then no deduction how ingenieus made will do. I live in the Netherlands with 50 Hz mains frequency. So your primary assumption was right.BTW are you implying that I will,then,blow up 'only'
my bass-speakers but stay alive because there is no danger
from my beryllium -units? (kidding).
Regards,
Nandric, you speakers are simply in no danger regardless of what you do with the arm. It all has to do with what you do with the volume control :)