Review of Quadratic MC-1 SUT With Comparisons to Other SUTs

Returning to this excellent thread, which serves as a handy reference guide on SUTs... @mulveling, by now you’ve no doubt received your EAR MC4. How does it stack up against the MC3 and, by extension, the others mentioned in your exemplary comparison? Inquiring SUT users need to know! :)

Thanks to this thread and TTVJ’s loaner program, I’ve had the Quadratic in house for a few days. Enjoying it a lot with the Dava cart. Will try Koetsu and Miyabi soon. @mulveling I found the low gain setting to be even purer and more open than the high gain. Have you heard the same?

it remains, unlike my ipad typing skilz, a cool thread…..

Jim

@kdogsy 

Interesting - I didn't realize Cardas had such a wide variance in capacitance by model, though it makes sense. Clear is definitely the one you'd want for this application (very good numbers), though a bit pricey. Cardas used to publish capacitance specs on some of their older line, and IIRC that's where I saw some very low spec'd capacitance numbers. 

And yes, capacitance is always directly proportional to length, which is why it's best to locate a SUT box where you can use less than 1m :)

Generally what you want to see for a cable in this role:

• Light shielding (nothing over the top). Shielding adds capacitance. Some will propose no shielding, but that can be tricky with phono signals.
• Non-braided geometries. The closer the average spacing on +/- conductors, the higher capacitance (braiding tightly couples them). Stax headpone cables use a ribbon configuration with conductors spaced far apart for this reason (electrostatic energizers is another application that does not like excess capacitance).
• Small AWG (wire gauge). ICs with large gauges like 19 - 21 are great for hooking up amps, but bad in this application. 
• I'm not sure whether the current Audioquest battery packs (RF trap) contribute to capacitance - their Thunderbird speaker cables measured higher capacitance with batteries attached. It's something to consider, and maybe even ask them about. 

@mulveling i asked Cardas for capacitance specs on their cables as I don’t see this information displayed for any cable brands I looked at. This is what they sent me : 
Cable/ Pf per foot

Crosslink/49

Iridium/48.32

Parsec/57

Sky/37.2

Cygnus/48

Reflection/28

Clear/15.27

Clear Beyond/34.5

so the Clear range looks by far the lowest and I now understand the short cable is because of potential issues that could occur with low capacitance cable will multiply in line with cable length… My layman description. 

Very nice read on some high end SUT's. I appreciate the effort that went into writing it. Since I  own a Denon AU-340 with Tamura transformers and haven't yet experienced any of the above mentioned units I'm curious as to where mine would fit. It's always nice to read post about different SUT's, especially when there are well written comparisons.

BillWojo

@mulveling The descriptions of the SUT's in use are very well worded amnd from my experiences of a selection of these, I do agree with much of what has been said.

Cinemags do push out in the upper mids' and inflate the presence in the listening environment. I've not got the Bass experience you have through ESL Speakers. 

I have a Hashimoto on standby and it is used mainly for a demonstration purpose only, the Model is very refined and not exaggerated in any frequency. I would refer to it as unremarkable. Where it excels is in comparisons, it really shows where other Designs have a clear separation from the presentation.

I know EAR for Pre-Amp's, Power Amp's, Phon's and SUT's, it was these dsigns that catapulted me into the mindset to own Valve equipment.

I have been listening to two versions of EAR Power Amps in another system for quite a few years.

I share a similar inquisitiveness to yourself. If you can get a loan or demonstration of an EAR TX-4 The Head SUT, you will be in for a treat.

The Structure A SUT's are a Brand to keep a look out for, these have been a very satisfying experience and are to be the next of the SUT's demo'd in my home system when it is set up again. I have it on good authority the models I have heard are to be superseded by a ???  version, I can't wait, hopefully I can manage to encourage the bringing of them all around to experience.

Good Blog this, update as the experiences grow, I'll be hovering for a read. 

@kdogsy 

Hi Kim,

Awesome! Both the MC-4 and Quadratic MC-1 are wonderful SUTs. They're still my favorite 2; I still own and enjoy both a lot. I think (and hope) you'll be blown away by the difference over your Classic's built-in SUT. Your Koetsu will be a wonderful match. Maybe it is a lot of cartridge for that table, but I've heard Koetsus sound shockingly good on modest setups. 

Yes, the cable coming out of the SUT needs to be low capacitance design and ideally less than 1m. 0.5m is ideal if you can make it work. If not, try to do 0.6m or 0.7m. 

Not sure your budget, but here are the low capacitance designs I know of:

• Bob's Devices sells a very good sounding IC for $400 @ 0.7m
• Cardas Interconnects (past and current lines) are generally VERY low capacitance. Various prices by model. I believe the Bob's Devices cable is based on Cardas. 
• Audioquest's current "Bridges & Falls" series is well suited for this role - much better than their more expensive (high capacitance!) IC lines for this application! Big Sur is where they start to get decent (using the best copper), at $158 for 0.6m. Then they go up from there. For your setup I'd probably go for Sydney @ $250 or Yosemite @ $452.

Mike

@mulveling thanks for writing such an informative review on these SUT’s. I found this thread after considering the Quadratic MC1 with Todd- the vinyl junkie…. I have however pulled the trigger on the MC4. Up until now I have been using the sut in my EAR Phonobox classic and this will be my first time using a separate. My cart is a Koetsu Rosewood Standard and further downstream I have Leben cs600x and Devore Fidelity 096. My TT is a Technics GR and I do wonder if I have over specked my kit with this tone arm. Personally I think things sound pretty good right now and I’m excited for the new SUT and to try the Koetsu with more appropriate loading. My question to you or anyone else is I hear the interconnect from SUT to Pre-amp is important. Can you pls advise me on how to choose correctly or better yet suggest a couple of options that are at the value end of the scale but still appropriate for my gear. Many thanks 🙏 and look forward to following your journeys. Kim

@mulveling This is a total aside, but what is your reasoning for keeping the SOTA Nova with the Clearaudio? Is there a type of music where the SOTA is called to service more?

I have re-read the MC-1 comparisons three times. Highly informative!

i have moved from a vintage preamp with built-in phono ( MFA Luminescence ) to a transimpedance phono stage ( channel D Lino C2.0 ) with the idea of avoiding all the matching / mismatching issues involved with SUTs. However, I have a Audio Tekne MC 6310 low output / impedance cartridge and have bought a AT dedicated SUT ( MCT 4818 )  and a tube phono ( Sun Valley EQ 1616D ) to experiment. 

In both the compares with the Koetsu and EAR SUTs the MC -1 is described with more bass emphasis. An important data point if I were to adopt it. Still early stages in my learning curve with SUT. And really enjoy this thread.

I wouldn't expect an MC SUT to experience any notable sonic degradation in its lifetime. To think about it another way - the OPTs in tube amps from the 1950s & 60s still sound excellent as long as they weren't egregiously abused and trashed - and when they do have an issue, you'll know it. They handle orders of magnitude more power than an MC SUT.

As our audiophile toolkit goes, transformers are pretty robust and reliable. Better to save our worry for the tweeters, keep our connector contacts clean, etc. 

The Jensen and EMIA MC SUT's are definitely on my want list to try.

 the core lamination's are a special nickle or steel that has good magnetic properties. That can get magnetized if a DC current is run through it.

magnetic transformer laminations are soft magnetic materials specifically alloyed and annealed to not retain any magnetism.  The idea that any DC offset will somehow leave a core partially magnetized is an urban legend not grounded in physics.

dave

The wire is non magnetic but the core lamination's are a special nickle or steel that has good magnetic properties. That can get magnetized if a DC current is run through it. Normal operation only puts a AC current/waveform through it. That shouldn't leave any residual magnetism. 

BillWojo

Can the SUT's wire become magnetised ? 

Nothing to service except the RCA connectors and switches if they have them. There is just a set of transformers that never wear out. More than likely it's just not a good match or needs loading of some sort.

BillWojo

Is it possible for a SUT to diminish in performance? Although my EAR MC-4 is working in a vastly 'flavoured' different system to your's - solid state vs valves - it sounds soft and lacking in dynamics compared to my other SUTs - Music First Audio V2, Auditoreum 23/Denon 103, K & K Lundahl 1931cu and Fidelity Research FRT-5. Do SUTs saturate? Can a SUT be serviced back to original performance? 

I'd like you to hear the Jensen old Audio Interface (40 & 80 ohm versions), their new version MC-2RR ISO-MAX 2 low & high) and my purchase of the 40 position Zesto Andros Allasso.  $550 and $3600 .   I perfectly matched my former Benz Ruby 3 at +16db at 220 ohms, not to bright or too dark-a perfect fit.  With my new Dynavector, a wider choice was possible as the cartridge is more forgiving of impedance matching than the finicky Ruby3.

as in life, also in typing. Take no prisoners, admit an correct no misteakes…

@three_easy_payments

I have to say, I’m really disappointed by the lack of enthusiasm and engagement on this thread following all the efforts and truly useful listening comparisons you’ve conducted and decided to share. This should be the essence of what this forum is about, and on any other audiophile forum this thread would have garnered far more interest and participation.

Well, I don’t agree with you on this, I have enjoy reading a lot of well written, informative and thoughtful threads like this one (kudos to mulveling), I not always participate to the discussion, just read and learn.

I feel this is sadly becoming emblematic of the state of this forum as pages upon pages get devoted to gear that in many cases the OP has never heard but is gushing over based on reading reviews... faced with reading bickering, hyperbole, and heavy-handed opinions without any listening basis whatsoever.

Totally agreed! Sad to see this forum been polluted by some self-appointed expert and snake oil...

Is it “a SUT” or “an SUT”?

Exactly…some of us are digesting the in depth comparison of so much gear … my system currently does not employ an SUT ..but when i was evaluating phono pre, some of the 12 i brought in to audition did..notably w Cinemag Blue..so this post helps me calibrate a BIT of what i heard..knowing that my overall system in nothing like the OP. i find this thread helpful should i go down the SUT path in future…

Best to all ! Enjoy the music..

Jim

Agree with @lewm. There is lot to absorb here. I always enjoyed reading @mulveling posts and have deep admiration for his thorough approach to audio. We have communicated few times here and on his virtual system. I know for a fact that this amazing thread will come in handy when I am ready to tweak my analog system in near future 😊

@three_easy_payments 

Thanks for the kind words. I think the response has been fine - this is hitting a small segment of an already small turntable enthusiast group! Sometimes I get a "thank you" Private Message for a past post I had forgotten about, which makes it worthwhile, as well as the valuable ability to (slightly) organize my own thoughts :) 

The double post was unintentional and I see it affecting other users - I hope the Audiogon team fixes that. It might have something to do with the preview/edit before post? Unfortunately I let the comments get split up between the 2, which doesn't help. 

@lewm 

3easy, isn’t it a bit premature to bemoan a lack of attention to Mulveling’s nice post?

Perhaps.  And maybe I'm channeling my overall frustration with this place lately.  Let's see if this thread gets more traction over the next week.

People who want their SUT to "get out of the way" might really love these. But if you go too far into that philosophy, then pretty soon you're constantly talking about "wire with gain", upgrading your cabling to Monoprice, abandoning all vinyl for digital, and sharing pics of your Benchmark gear & measurements at parties :lol:

HEHEHEHE

3easy, isn’t it a bit premature to bemoan a lack of attention to Mulveling’s nice post? There is a lot of meat here to chew on, and we haven’t even heard from some of the pros, like Intact Audio and Atmasphere. I was only trying to point out, as M understood, that it is difficult or problematic to describe the SQ of a SUT out of the context of a system in which you heard it. 

@mulveling I have to say, I’m really disappointed by the lack of enthusiasm and engagement on this thread following all the efforts and truly useful listening comparisons you’ve conducted and decided to share. This should be the essence of what this forum is about, and on any other audiophile forum this thread would have garnered far more interest and participation.

I feel this is sadly becoming emblematic of the state of this forum as pages upon pages get devoted to gear that in many cases the OP has never heard but is gushing over based on reading reviews. I’ve been spending less time on this forum over the past year and may totally fade away as posts like yours are few and far between and we are otherwise faced with reading bickering, hyperbole, and heavy-handed opinions without any listening basis whatsoever.

@mulveling Really fantastic review! It’s great to hear from someone who has listened to so many SUTs head to head and reflect on the experience. As @tomic601 indicated, it’s refreshing beyond words to read such a fair and balanced assessment which is based solely on listening and not hyperbole derived on what you read from other’s reviews.

@lewm

Thanks Lew - it’s true, these comparisons are largely strapped to my VAC Renaissance SE as the MM stage @ 47K loading. I’ve had many other phono stages at lower price tiers, but the VAC clobbered them all, and gets all the play time. The SUT interconnect also has a big impact. I’ve learned to keep that cable low capacitance, and as short as possible, or else it WILL let its presence be known.

The Renaissance phono stage is definitely on the "romantic" side of the spectrum. However the SE upgrades clean it up towards neutral, offers gobs of detail, and I’m confident it’s not doing anything weird or "unconventional" to the signal. It just sounds beautiful! Very low noise floor for a tube stage, too. 

@pcosta

No experience with Jensen MC SUTs yet. I keep wanting to try their better MC transformers, but it hasn’t happened yet. I’ve enjoyed gear which uses Jensen transformers in other roles; I know they make good stuff!

@tomic601

😂

@jc4659

Thanks, jc!

On the lower end, the value winner is a pair of CineMag 1254 ($360) in a simple or DIY box, or included as an option in your phono stage (e.g. Rogue Ares). For myself, I find either the EAR or Quadratic to be the value winner (to be determined). If you’re already looking to spend north of ~ $1K+ on a SUT, and you have a very nice cartridge/table/phono setup, just go right to the playback level afforded by these excellent SUT boxes, and don’t look back! For cartridges with a relaxed top end like the Koetsu Platinums, it’s probably smart to favor the EAR over the Quadratic.

That said, if you blow your budget for more expensive SUTs on a new Koetsu, you can also do just fine with a Bob’s Device Sky (20x or 30x are ideal though 40x works too). They show up used sometimes. I got a Sky 20 for $650 that way. It’s a fantastic match to Koetsu without spending a LOT more on the Koetsu SUT. I still like the EAR/Koetsu pairing better, but the Sky does very well. 

Some of these transformers are available as raw parts sans box, while others are only available as a finished product. Of the finished-product only SUTs:

• EAR MC-4: $2295. My discontinued MC-3 listed for a bit less.
• Quadratic MC-1: $1795 (recently DOWN from an original $1995)
• Bob’s Devices Sky: $1375 in a typical configuration
• Bob’s Devices 1131: Discontinued? $1195
• Koetsu Wood-Box SUT: Discontinued. Retailed somewhere around $3500 - $5000 by the end of its run.
• Koetsu Metal-Box SUT: New version (I haven’t heard it yet). $4995.
• Choir Audio H7: Discontinued. $1800

The following transformers are available for purchase as parts. Obviously, finishing in a nice box will add to cost. Prices are listed per PAIR, when know:

• Lundahl LL1931: $470 from K&K Audio
• Lundahl LL1931Ag (silver wire): $1500 from K&K
• CineMag 3440A Red: ~ $200
• CineMag 1254: ~ $360
• Hashimoto HM-7: ~ $1000? (Ebay)

Additional notes: Rogue Audio offers the CineMag 1254 upgrade in their Ares phono stage for ~ $400. Their stock Ares comes with CineMag 3440A. The Ares Magnum upgraded model comes standard with 1254 - and it makes a large difference (more than the other Magnum upgrades).

When I asked Kevin Hayes from VAC about using LL1931 versus LL1931Ag in their phono stages, he claimed that regardless of cost, he found the copper LL1931 to sound better. I’ll say that the LL1931 and LL1931Ag are much more similar sounding to each other, than they are to any other transformer. And I can see where Kevin might find the timbre of the copper LL1931 to be more natural. However, it was not an exactly equal comparison in my case since I was comparing the built-in LL1931 in my VAC Renaissance (which also adds some secondary loading) to a boxed K&K LL1931Ag unit.

Lew don’t forget the magnetic field in his neighborhood, solar flares, humidity, single malt or ?

Any experience with the various Jensen models?

Nice review and very much appreciated!  I would have liked to see retail prices for these SUT's (which obviously I can find myself) and your nomination for a value leader out of the bunch.  Again, thanks for the clear and concise comparisons!

Thank you for the very articulate critique of your various SUTs, but you do also realize that the tonal balance as affected by a SUT will be very dependent upon the specs of the cartridge to which it is mated (Signal voltage output, internal resistance, inductance, etc.) and to the phono section it is feeding. Moving magnet phono circuits certainly add their own colorations, whether we like it or not. Much of that relevant detail is missing from your otherwise detailed analyses. Also, it is possible for a person to want his SUT to “get out of the way“ and yet still enjoy vinyl without resorting to digital, ever. I for example am such a one; I do not own, nor have I ever owned a SUT. High gain phono stages also have their foibles of course.

@tomic601 

Thanks so much Jim - and right back at ya :) 

Always love your posts. You are a high sample size audiophile helping others. You increase the musical IQ of audiogon by owning, listening to and optimizing a lot of gear versus claiming you own the absolute best before even hearing it…blather..blather, etc. You are trusted and respected. My complete admiration ;-)

Jim

Some cart pics, since we can inline now...