Step Up Transformer Question

Surprised me too - but it turned out to be quite accurate, in that the Epoch is smoother, more refined. That's the KRSP with diamond cantilever option, which may alter things.

I expected the wand material to make a more subtle difference, too - and I was wrong again.

While the Epoch may certainly be superior sounding to the Koetsu, for a given listener, this may be the first time I ever read that someone thought a Koetsu cartridge, especially a "KRSP", was "too analytical". But then again, that was the guy who sells the Epoch. (Don't get me wrong, I love MI cartridges, and I would love to hear an Epoch.)

@mulveling Your tastes are pretty refined - obviously - so I would keep that in mind when deciding on a model. Mr. Grado might be able to help you with this decision.

@mulveling I was wondering the same thing a year ago. I talked to Mr. Grado about linear tracking, he said that he hadn’t the faintest idea - but I could try a $100 cartridge and see. It didn’t sound all that good (compared to a KRSP !!) but it worked on the LT. Mr. Grado also said that he found the Koetsu to be a little analytical for his taste! So splurged on the Epoch.

Good choice for me. A little smoother, more dynamic, and far better tracking (than KRSP d/c). But last week I tried a sapphire wand in my LT, and now the Epoch sounds a little analytical! So it’s back to natural fibre composites - panzerholz or pampas grass, not sure yet. Will have to optimize. Would you like to be PM-ed?

@rmdmoore

Awesome! That’s great you’re liking the result with new cables and SUT at 30:1. Lowering phono stage gain to compensate could be good when you have the option, but since the cartridge is so low at 0.2mV, it’s probably just fine to run at the higher gain too. If you’re doing tube type swaps for gain, then that itself will impact the sonic result beside just the gain change.

@mulveling Your dislike of Lundahls is interesting. I only have experience with the 1931 Ag, and it sounds pretty good when stepping up my Koetsu.. Not quite as clean or warm as my differential amplifier stage, but close.

Now that I’m using a Grado as my primary stereo cartridge, it’s a moot point

@terry9  They’re fine SUTs. Just not for me, sonically. I’ve tried them countless times, numerous chances, and still never stuck with one. Have LL1931 (copper) built into my VAC phono stage (easily bypassed). Had a K&K box with LL1931Ag (silver). Have LL9206 built into an older full-function VAC preamp - the LL9206 really lacks badly in detail compared to better SUTs, but at least I like its warmer tonality compared to the bigger Lundahls. In the end I still prefer the EAR’s, blue label CineMags, or the Koetsu SUT - though the latter can be a tough fit with non-Koetsu carts because it’s (surprisingly) a little hot up top.

I would still probably take a LL1931 over some/many active MC stages. I did have better results with the copper version in my system.

And I’ve read about your Grado move with much interest! I’ve been wondering if it’s worth "dipping my toe in" at the Mastger3/Reference3/Statement3 level just to get a taste. Or whether I have to go all out to Aeon or Epoch, to be sufficiently impressed.

@lewm the Bellari has a switch that changes the turns ratio between 1:12 and 1:30. If you're asking how I'm reducing gain in my phono stage, I'm changing tubes. It's a strange design but in my Rogers PA-2 the way you adjust gain is by switching out the tubes in one of the gain stages. 

How are you reducing phono gain in the Bellari?

@mulveling so the new cables came and I was able to eliminate the hum. Once I did that I played with things a bit. Started at 1:12 with maximum gain in my phononsrage. This sounded great. It seemed to have more body and depth than whatever SUT is in my phono stage. Next, I switched the SUT to 1:30 and decreased the gain in my phono stage a bit. This sounded even better. More air around instruments, felt like I could really hear the room on some recordings. 

Seems to me you were right, that once I got the hum situation squared more gain in the transformer and less in the phono stage was the way to go. Feel like 1:30 with max gain will be too much and overload things. 

I appreciate all the input from everyone regarding SUTs. I think, for now, I'm going to stick with the little Bellari. Seems to be excellent bang for the buck. At some point down the road I'll get something big boy but for now, while I'm adding a second tonearm and cartridge, this will do. 

@mulveling Your dislike of Lundahls is interesting. I only have experience with the 1931 Ag, and it sounds pretty good when stepping up my Koetsu.. Not quite as clean or warm as my differential amplifier stage, but close.

Now that I'm using a Grado as my primary stereo cartridge, it's a moot point.

dogberry

thanks, i'll check them periodically

@mulveling it's funny, that's what I was initially thinking. I messaged Ned Clayton about an SUT that would have some adjustability so I can play with different gan ratios and then I can adjust my tubes in my phono pre accordingly. I'll probably end up doing that. 

Ralph from Atma-Sphere also mentioned, as did Roger, that a lower ratio will be less prone to noise. I'm waiting on some new cables to come next week to see if I can eliminate some of the hum I'm getting with the Bellari. As you said, might need to try different grounding schemes. I feel like that's a whole other thread, lol

@rmdmoore  I enthusiastically disagree with this part. With a SUT, it's a given that you absolutely have to get the grounding and cable shielding right - whatever the ratio. Once you do, hum noise will disappear and the only noise you should be hearing is a "hisssssss" or "shhhhhh" noise from the active RIAA stage of your phono (the noise part of its signal-to-noise spec). Using a higher ratio SUT allows you to lower preamp volume while attaining the same signal SPL, which pushes this noise DOWN. It's not so much a matter of total gain (yes everyone agrees 70dB is high), as it is about optimizing the *structure* of that gain. The actual signal levels hitting each part of your analog chain up to the preamp volume control - this is what matters!

Of course it's a balancing act - if you push SUT ratio too high you risk loading the cartridge too heavily (which will cause loss of signal), overloading your RIAA stage (bad distortion), and of course the SUT itself will distort more at higher ratios (all else being equal). Higher quality SUTs will distort less at the same ratio. A good rule of thumb, for most MC cartridges (coils wound on iron), is to choose a SUT so that your "calculated" signal coming out of it is ideally 5mV (this is what hits your MM / RIAA stage). But anywhere in the range of 3.5mV - 7.5mV is usually considered good (I listen loud and like to ride on the high side of that, personally). So your 0.2mV Windfeld into a 10X SUT is only 2mV. That sucks, IMO. I can't believe people are recommending that lol. A 20X would give you 4mV and a 30X would be 6mV. I'd choose the 30X there, but either would work great. 

If your 2nd wood cartridge is also 0.2mV that would be great, and the same SUT would likely be optimal for both. But that's also why many SUTs come with 2 or 3 taps. The Sky 30/15 for example, would work great with a 0.2mV cart at 30X and a 0.4mV at 15X.

One other way from recollection used by myself as a method to discover what might be contributing to producing Hum, is to put a finger on the Metal of the Input RCA. Use the Spare Finger to touch the other Metal Parts, other RCA's, SUT Chassis, SUT Covers is external mounted, Phon' Chassis, Pre RCA's and any visible screw heads on any device local to the finger in contact with the RCA. 

If one of the contacts being made substantially reduces Hum and it is in-line, a small gauge wire used as a earth bridge might make the Hum inaudible at listening levels with a ear about a metre from a speaker. 

I have a single wire removed from a Telephone Extension Cable used as a Earth Bridge, a friend soes very similar, but also has pure copper crocodile clips attached to make an improved contact that a loose wrap.  

@mulveling I appreciate your input. I spoke with Roger at Roger's High Fidelity who makesy phono stage and he said that the 20db I'd get with 1:10 will get me a total of 70db of gain which is what I'm currently using with the built in SUT. It seems quite good with my Windfeld Ti. Ralph from Atma-Sphere also mentioned, as did Roger, that a lower ratio will be less prone to noise. I'm waiting on some new cables to come next week to see if I can eliminate some of the hum I'm getting with the Bellari. As you said, might need to try different grounding schemes. I feel like that's a whole other thread, lol

I just visited my Old Group Buy Thread for 1254's.

The Fourth GB was not gaining much momentum, and interest party posted the following.

"I ended up buying them directly from Cinemag. $175 each as of Jan 20th, 2023."

Add to this cost Low Eddy RCA Chassis Connectors and Low Eddy RCA's for Cables, and I am confident the experience had of the 1254's will be quite different for the better, producing a sonic that is improved over the ones reported on without such connectors used.

I would just go with a Ned Clayton 1254 until you figure out what's what.  You may find out that a SUT is not for you or not much better than the one you have.

The 1254s are good and fairly inexpensive.  Ned makes them with 4 settings so you can fool around with all the gain/imp.  I think 1254s are a good place to start, not cheap and not way out there and good performance.

Get into different cores and windings and it's an event horizon for your wallet, sucking out all your cash!

SUT thread on SHF that may be useful.

1:10 is way way too low for a 0.2mV cartridge, regardless of your downstream gain. That wouldn't last a second in my system. The Bob's Devices Sky 30/15 would probably be perfect for you. I really like the sound of the Sky's and also the EAR SUTs (at higher cost for the EAR). Not a fan of the Hashimotos or (especially) Lundahls, which lack the "fullness" and flesh I adore about SUTs. I've used a Windfeld Ti with EAR MC-3 (and current MC-4) in fact, and it sounded great - much better than the Lundahl LL1931 in my VAC phono stage. 

I've also had CineMag 1254 (blue) in a phono stage and they are excellent for the money. Sky are better for sure, but I was still impressed by the 1254. The CineMag 3440A (red) sucks - don't even bother there. All the good CineMags have blue labels. 

You will have to experiment with cables, grounding schemes, and SUT location to eliminate hum. Bob (of Bob's Devices) can probably help you out. Try to keep the outbound cable shorter than 1m - 0.5m is best. 

Lundahls and CineMags end up in a LOT of other-brand SUT boxes and phono stages, so always try to figure out what is what. I try to avoid Lundahls and red-label CineMags, but it can't always be helped. The Ortofon Verto for example, uses Lundahls. Lundahls also end up inside lots of tube phono stages, much to my chagrin. They are recognizable by their rectangular case. 

@rrc4860 thanks for that input. I was looking at the MCX which is 1:10 and a bit more expensive. Thinking there just be a higher quality transformer inside? I'll call the guy at Britaudio next week. 

​

Regarding that Rothwell MC1.. I purchased it through this fellow, who was incredibly helpful and patient with my several questions:

I have a Rothwell MC1 that boosts my Hana ML into a McIntosh MA5300 and it sounds terrific. Cost under 400 bucks. Made no sense to buy a phono preamp on top of a 5k plus integrated amp. I can recommend the Rothwell. It's a magic little box for sure.

@rmdmoore This is why Jensen. You can get transformers from them that are only 1:4 or 1:8 which allow for greater bandwidth. There's no point in having more gain than you need since there are always performance tradeoffs to get the greater gain.

@atmasphere Ralph, thanks so much for your input. Yes, the plan is to use the MM input and which has about 45-50db of gain with the current tube complement. I should really only need about another 20db which, if I understand correctly, would be a 1:10 transformer. That's what is in my unit on the MC side according to the designer. Seems like that's really all I need then. There are some good deals on recently discontinued Hafler SUTs that had Jensen transformers in them. Anybody have any experience with those? 

My question is where do I go from here? Bob's makes the sky 30 which is switchable from 1:15 to 1:30 which I like because I can play with the gain tubes in my preamp and potentially go to a quieter 12au7 than the 12ax7 that's currently in there. Will that be a real improvement?

@rmdmoore We've worked with SUTs a lot over the last 40 years. @lewm's suggestion of Jensen Transformers is an excellent one- they make some of the very best in the business at any price.

One thing you learn very quickly is that you want the least amount of step up possible so as to work with your cartridge. The more step up you go for, the more issues the transformer can introduce.

If you have 0.2mV you really only need 60-65 dB of gain if you have a regular line section in your preamp. So you should be using the MM input, not the LOMC input. 

The other thing that is tricky about SUTs is loading. The loading does not affect the cartridge (other than measurably and audibly limiting its high frequency bandwidth; lewm already linked to the thread on the Steve Hoffman forum that shows what is really going on), but loading is critical for any SUT!

If the SUT is improperly loaded it will either 'ring' (distort, so adding brightness) or be rolled off if loaded too heavily. Jensen transformers has published a pdf file that shows the correct loading for their transformers when used with most known LOMC cartridges. Mot SUTs made for a specific cartridge are designed to be loaded at 47KOhms with 100pf of capacitive loading (which is about the capacitance of the tonearm cable 1 meter long); IOW they are designed to be plug and play.

But if you use a different cartridge with such an SUT the loading will be off and it won't sound right! That is one reason I like to work with Jensen since they did their homework, figured out the loading values and so their transformers work with almost any cartridge.

@elliottbnewcombjr I use WBT locking connectors, but they still need a wiggle or a jiggle every now and then to decrease resistance caused by accumulated crud. (I guess they might be gold plated but it is impure gold!)

@rmdmoore As stated in a earlier post in this thread and in another thread very recently.

I am a user of Valve equipment who much prefers the end of a Valves produced  Sonic that leans heavily towards transparent.

This has made me inquisitive and searching for items that assist with keeping the sonic where I prefer. As stated, I have been demo'd numerous SUT's across many years and state with full conviction in my system and in other systems, SUT's add Richness to the Sonic being produced.

In some cases it is a subtle underpinning of the Sonic, and at the other extreme, the sonic can be Bass Laden and very very loose in its shape and roll off.

My 'Gut Intuition' strongly leaves myself feeling the use of a Nano Crystalline Core has reduced the perception of Richness using a Copper Winding to the least I have detected it. Also the impact it had on the Cart' was quite something, the sense of effortless function and the projection of the sonic, had one feeling the system had gone through a very expensive upgrade. The system it was demo'd on has been via a Valve Phon' close to my own in use design, a Pre Amp' that shares very similar design to the Model I am having produced, EAR Valve Power Amp's and ESL Speakers. This system has similarities to my own inclusive of the ESL's.

As stated the Nano Crystalline Core with the Silver Winding that was not a ideal match for the Cart' in use, was equally impressive for other reasons. This had the most voluminous Sonic, extra pumps of Volume were seemingly added to the Soundstage. I am no stranger to this perception, but using older experiences and recollection this came at the expense of a undesirable colouration, one that is way beyond what I seek. The Structure A Silver Winding, offered all this Voluminous perception, as well as maybe being the most Transparent SUT ever heard.

Hence, this Brand is Shortlisted for Home Demo's.

It is good to see that other Companies have become aware of the value of adding the nano crystalline cores to their range and individuals like yourself have become interested in the notion of adding it to a SUT.

All SUT users, who prefer the Transparent End of the sonic that can be produced, will have to wait for patiently for the time when PC Triple C Wire Wound Tranx's are being made, to get to the next exciting level of sonic that can be created.

I'm hoping for Cart' Coils, Lead Out Pin's, Wand Wire (Already Achieved), SUT Windings to be produced in PC Triple C Wire. My World of interest in Audio will become a place with new enthusiasm to encounter such items. 

Interconnects, Power Cable, Speaker Cable, Internal Speaker Wire and Internal Hook Up Wire are all uses for PC Triple C Wire that I have now experienced in use.

Internal Speaker Wire being the only device not able to be A/B compared as a Demo' to a Typical version.

PC Triple C Wire has proved as a result of Demo's to be the correct choice made as a Copper Wire.                

Hi @lewm ,

I used the original EAR 834 phonostage and then improved the DIY version based on the EAR 834 phonostage schematics that I built myself.

I used Ortofon Rondo Bronze with Altec 15095. Then I used Ortofon Jubilee with Altec 4722. After that I moved to EMT TSD15. I tried Altec 4722, Jensen 44 and Hauffe with EMT. Altec did not match the EMT cartridge well and Jensen and Haufe matched in terms of impedance and tonal balance was OK but sound transparency and dynamics were very bad. After that I bought Tamure 83 that sounded great with an extra load resistor. In the end I bought Tamura MC20 that was even better morey dynamic, deeper bass, bigger soundstage.

In my DIY 300B SET amp I use Hashimoto output and interstage transformers and they are great. I used James Audio transformers before that were really good, but Hashimoto gave more low level details. I think Hashimoto MC transformers should be good as well. 

I heard from people that vintage Houfe transformers are magical. It is possible, but the new Haufe production is a total garbage. Jensen 44 is a bit better but Tamura is a different league.

I changed all my RCA interconnect cables to Locking Connectors. Mess with any cable, others do not get disturbed.

I got 2 sets of these video cables to make 3 pairs for audio, color coded ends, locking connectors, zero noise, great price. These are 12 ft long, I got 6 ft long, you just need to find the right length

these come various lengths, with Locking Connectors, many other choices. Remember, Amazon has easy returns if you find it is not the cable causing the hum.

Alex, your opinion is your opinion, but it is not helpful if you don't provide more information, like what turns ratio, what cartridge with what internal resistance and voltage output, and what phono stage with how much gain? 

@pindac I see now on the Erhard audio page the area that lists nano crystalline transformers but I don't see any that are marked as SUTs. Will have to give them a call

I had a number of MC step-up. All of them sound completely different. Day and night difference.

I had:

1. Altec 15095

2. Altec 4722

3. Haufe T890 (the modern production, not the vintage one)

4. Jensen 44 

5. Tamura TKS-83TWIN

6. Tamura MC20 (Sun Audio SAT-1000)

The worst are Jensen and Haufe. Really bad.

The best are Tamura.

Altecs are in the middle. Not bad.

If the load is too small (too high impedance) and sound is too bright you can solder the resistor (from 100K down to 15K) to the secondary of the step-up transformer. Smaller resistor - darker sound.

Amorphous is not Crystalline.

The following is a bit of other forum talk on the subject.

"According to Per Lundahl, writing by email, "Choice of core material is a question of taste. Our top-of-the-line MC transformers are available with either our uncut amorphous strip core (like the LL1931) or with a conventional mu-metal lamination core (like the LL1933). As it has turned out, the amorphous-core transformer is most popular, but the mu-metal lamination transformer is still preferred by some audiophiles. In THD ... and linearity measurements, the mu-metal lamination version outperforms the amorphous core version, but in listening tests, the amorphous core usually wins."

"I asked Per to explain the metallurgical differences between mu-metal, amorphous cobalt, and nanocrystalline transformer cores."

"In true amorphous material, there should not be any crystal structure. Atoms are randomly oriented, and there is no repeated structure such as you find in most solid metals. To achieve this, the melted metal is cooled so rapidly that atoms get stuck in their random positions. ... This very rapid cooling requirement is the reason why amorphous metal is only available as thin film, about 1 mil (0.025 mm) thick.

"To achieve nanocrystalline material, special amorphous iron is carefully heat treated at very controlled temperatures. In this process, very small [nano]crystals are formed."

 

Not to make an already very confusing thread even more confusing, but Jensen make great  step up transformers, too, at a reasonable price.  And their staff of engineers are very knowledgeable and helpful to DIYers. Go for their top of the line, and you won't be sorry.

@pindac I'm chatting with an eBay builder about building one with lundahl 1941s. The core is listed as amorphous. Is that what you're talking about? 

@rmdmoore I would have to get it confirmed by the individual who loaned the SUT's for the Demo's but do believe the Sculpture A with a Copper Winding was 1:26 Ratio.

The nano crystalline core is not too commonly seen on audio, and it is this material, that certainly seems responsible for a proportion of the standout impression made.

Lundhal are offering this Core Type on some of their designs for a Tranx. 

@elliottbnewcombjr the Bellari SUT I have now to play with has 1:30 as well and when I switch to that the hum does not go away. I really think it's cable related but can't prove that until I get more cables. 

@pindac you did mention the sculpture A prior. What turns ratio did you use for a 0.2mv cart?

@terry9 I've looked at that option a little bit. There are even some premade boxes to put SUTs in online. You can buy kits from lundahl's US importer and I've thought about that as well vs getting a Rothwell from the UK with decent lundahl units in it. 

Again, thanks everyone for all the input. Super helpful. 

@dogberry In a earlier post on in this thread, I make it known how impressive the Sculpture A SUT has been as a Copper Winding and produced as an ideal match for a 0.2mv Cart'.

In the same session a Silver Winding SUT from Sculpture A that was not the ideal match, was also used on the same 0.2mv Cart', which proved to be equally impressive for different reasons for how it produced a sonic.

From all of my experiences had using SUT's, these are the most attractive I have from recollection.

Using ones ears to assess whether the interface is an attraction or not, really does seem to be the method. 

I have had SUT's demo'd that are ideal matches for the Cart' in use, where there is noticeable overbearing perception of Bass Weight being produced, as well as a unattractive Looseness of the Bass Notes. Certainly not my flavour of choice.

Dogberry, The information contained in the referenced thread from Steve Hoffman Forum echoes precisely what Atma-sphere and Jonathan Carr (two authoritative sources) have been writing on this forum for years, loading an MC (at any resistive value above some multiple of 10 or greater of the iinternal R of the cartridge) should make very little to no difference in frequency response. Yet, there are an endless number of posts stating otherwise. I suggest to anyone interested in this topic to search these archives for their words. Even below a load equal to 10X the internal R of the cartridge, where you start to get significant loss of gain, due to shunting of the cartridge output to ground, the gain penalty is very gradual as you go down from 10X to 1X (cartridge internal R = load R), where 50% is lost to ground but also there is a potential loss of HF response due to capacitance at the interface, and almost all phono stages have at least some input capacitance.  The input Z does affect the phono stage in ways described by Atma-sphere.

Another thing - the higher the gain, the higher the distortion. Just something to keep in mind; don't buy more than you need.

And it might not matter if we carefully calculate the effective loading on the cartridge:

At the end of it all, if it sounds pleasing to you, it is good and you might as well be happy.

There seems to be a lot of markup in some SUT's. Why not buy bare transformers and put them in a box yourself? More control, more satisfaction, less money.

Sowter makes good ones. Lundahl makes several grades from good to great. I've used both. The Lundahl 1931Ag is quite unforgiving. Why not email Lundahl and ask? They are very nice people, and helpful too. So with Sowter.

Good luck!

Another Chart I had found: Cartridge Specs and Recommended Impedance Load. (you need to increase your monitor's zoom to read these).

I would check the specs of your phono Stage’s Sensitivity.

My McIntosh mx110z for instance, the MM Phono Input’s sensitivity is 3mv.

Signal Strength:

My cartridge’s output is 0.3mv. I use xFactor 18.27, thus signal strength to Phono MM input is 5.4mv. A bit of loss, guessing: perhaps 5.2mv, at least 5.0

Your cartridge 0.2mv x10 is only 2mv out to MM Phono input. I think too low, and perhaps the source of hum. A bit of loss, you might be getting only 1.8mv.

To find out, you could borrow a friend's SUT or Phono Stage with a higher xFactor, or order one from a source like amazon, with 30 day returns, try, keep or return.

Even if you don’t prefer it’s sound, it will tell you something about you existing x10’s involvement in the hum.

..................................

I prefer a stronger signal than mx110z’s 3mv minimum, keeps preamps volume centered, and closer to my MM cartridge’s 5mv output.

Switching arms/cartridges, the volume is not that different. I change volume remotely via my Integrated Amp’s Volume, thus preamp’s volume never moves, except when I often swish it full left/full right a few times, to keep the internal contacts fresh, it’s a Vintage control. I also use contact cleaner on all the controls once per year to prevent noise.

There are folks on here making blatant statements about diminishing returns of an SUT.  Being an owner of some of the finer SUT's (EMIA Ag, Cotter Mk2L, Tango Silver), I can tell you definitely that not all SUT's are equal.  The statements being made are of those that have systems that do not have the ability to differentiate a silver SUT vs copper or are basing it on their hunch. Don't underestimate the qualities of a higher end SUT, unless you have tried it and your system can handle it.

@elliottbnewcombjr you got it. The total gain with the inbuilt SUT and 12ax7s in P

place is 70db. My understanding is that if I place a 1:10 SUT on the MM input it will have the same.

@lewm I appreciate what you're saying and in truth, yes, I agree with not liking 12au7s in my line stage. I had a Rogue RP-7 and did a lot of tube rolling and in the end just didn't like it that much. I switched over to linestages with 6sn7 and I love them. You should check out the design of the Rogers PA-2 which is my phono stage. As I said, different tubes in one of the gain stages is how you adjust the gain of the unit. It's a pretty cool design. When I had a Hana ML cart, 12au7 were great, when I had the cadenza black, 12av7 worked well, with the current cart I need all the gain so 12ax7. 

@pindac I did move it around some and the hum didn't change much. Maybe the issue is more that the crappy RCAs have loosely goosey connectors that hum some. I ordered some new cables that should have better connectors and shielding so we'll see. 

@rmdmoore When using a SUT there is a possibility Hum can occur.

One cause of this can be using a RCA Connection that does not have a good bite.

The most simple method to try to remove/ substantially reduce a Hum, is to move the SUT around in relation to the Phon' and TT. Typically a movement away from both will start to create a change to the level being heard.

As short Cables are recommended between SUT > Phon' the movement of the SUT with a short cable may not be enough to have an effective control.

It has been a very long time since I done this, but in the past have also had good success using a very small gauge earth wire to bridge across connectors on the SUT. From recollection the Bridging has been done in line and not across channels. 

As for Cable selection, for quite some time now I have been an advocate of a Cable using PC Triple C wire for the Signal Path. My recommendation for RCA Connectors are outlined in a earlier post.    

mdmoore, I advised against replacing a 12AX7 with a 12AU7 first and foremost because those two tubes are electrically very different from one another. Upon further thought, I do seem to recall that there is something out there where the manufacturer officially OKs such a tube swap. I can conceive of doing it if there is some sort of switch that changes the load resistor and other parameters, when the user makes such a drastic change in tube types. Is that so, in the case of your unit? Do I recall correctly that you have a Bellari? The second reason I reacted so negatively is that I and many other hobbyists do not much like the sound of a 12AU7, when it is used for gain, typically in a linestage. Using a 12AU7 in a phono gain stage seems impossible; you would get very little phono gain, nowhere near even the 40db typically associated with MM stages. So, to sum up, the 12AU7 would be current starved in a 12AX7 socket, would result in very inadequate gain even for an MM cartridge, and would sound bad even if changes were made to the circuit so the 12AU7 would run properly. Better candidates would be 5751 (check me on the numerical designation of this tube, which is a standard replacement for 12AX7 when users want slightly less gain), 12AT7 (which also would run better if the circuit for a 12AX7 was slightly modified), and those are your best bet. There are some others in the 12A?7 series, e.g., 12AY7 and 12AV7 that might work, especially 12AY7, but the circuit really ought to be re-worked for such swaps.

I have and had several SUT - and there is difference- not sure why -

I had an inexpensive Denon AU-300LC- that was thin sounding...

I use now an E.A.R MC 3 (there is a newer model MC4) which is great. Also a Dynavector SUP-200  which is still in a box but apparently also good. but I can attest firmly to the E.A.R. . the Phono is in a nu-vista Preamp with mm Phono.

Cartridge is MC Ortofon Kontrapunkt b

YMMV of course - but this is my experience

Something wrong with the numbers

0.2 mv into 10x transformer is only 2mv signal out, that's too low for some/many phono inputs. Would cause volume controls near max, perhaps the volume control/circuit is noisy when raised so much.

10x is only +20db.

do you mean SUT xFactor 10 combined with the MM Phono gain will be 70db?

If something is great, but it hums, it ain't great.

Yes, I posted a photo of the SUT I use above: Fidelity Research FRT-4

Zero Noise at any setting, or arm selection.

My friend had some hum, Steve at VAS diagnosed it, the Grado cartridge that came with the Vintage JVC Turntable was the cause. He said MANY Grado's Hum. My Grado Mono (using PASS thru the SUT does not hum here.

My friend changed to a different cartridge on a spare similar headshell, nothing else, hum gone.

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One of the advantages of a SUT with multiple tonearm inputs, is you do not change the output cable or which preamp's input, it sends any selected arm out to preamp or phono stage.

@tomic601 you are correct sir. My wife is an absolute saint. She mostlybsupoorts my hobby and doesn't ask too many questions. She even used the turntable sometimes!

@elliottbnewcombjr was that TT set up with a SUT? I'm definitely getting more hum with the SUT and I'm attributing some of that to one of the cables in usong being crappy and picking up a lot of hum. Could be placement of the SUT but when I picked it up and moved it around it didnt seem to change much.