SUT decision: Ortofon Verto vs Ortofon STA6600L (Jorgen Schou)

[Pani]

Friends,
I am considering adding a SUT to between my Lyra Skala cartridge and RCM Sensor phonostage. I have noticed that even with a cheap vintage Ortofon SUT there is a clear improvement in terms of musical flow and drama when compared with using the phonostage standalone. At the moment I can get a Ortofon Verto which is a new generation SUT by Ortofon (using Lundahl inside) or I can also get a vintage STA 6600L which uses an original Jorgen Schou SUT inside. Which of them is preferable ? Will the old tranny hold when compared to a latest Lundahl tranny ?

[Ammonite Audio]

I can't comment on either of those, but without doubt the finest SUT that I've heard is MartinT's Choir Audio SUT, with Hashimoto HM-7 transformers inside. The HM-7 transformers can be found inside other SUTs too (take a look at eBay) but Choir Audio looks like better value.

[hifi_dave]

One of the very best MC step up x'mers I have heard is this....






A seriously good x'mer at a very reasonable price. Flexible, adaptable, deathly quiet and very well put together. It's a bargain.

Look up RFC on this forum for more info.

[Magna Audio]

There can be a bit more to it than one SUT / box is better than another.

Different step-up ratios will affect the impedance the cart sees and this can affect the sound a lot.
Some have switchable impedances to help match. Some don't. The ones that do are usually quite coarse. With an online calc you can work out what if any resistance to add. I have switchable 25ohm / 64ohm / 110ohm.

If the two you talk of match the cart and SUT then compare away

[Marco]

Having owned vintage JS transformers and used a Verto before I bought the (much better, IMO) ST-80SE, I have relevant experience on this matter, so will comment later.

However, Pani, what I'd like to know is why, with a Lyra cartridge, you want to use an Ortofon SUT? Wouldn't you be better with Lyra's own unit, called the Erodion, designed to specifically match their own cartridges: http://www.lyraconnoisseur.com/Produ...n/erodion.html



Marco.

[Reffc]

There can be a bit more to it than one SUT / box is better than another.

Different step-up ratios will affect the impedance the cart sees and this can affect the sound a lot.
Some have switchable impedances to help match. Some don't. The ones that do are usually quite coarse. With an online calc you can work out what if any resistance to add. I have switchable 25ohm / 64ohm / 110ohm.

If the two you talk of match the cart and SUT then compare away

Impedance is perhaps less important, once past a certain figure to protect the cart windings, than the HF performance of the SUT which is related to design, bandwidth performance (distortion) and leakage reactance (induction and capacitance). Things that are key to good SUT design include selection of a core which will allow the full bandwidth performance (usually mu-metals for SUTs) and the use of mult-leaf windings.

There's nothing wrong per-se with including dip switches for altering loading, but you may be surprised just how few cartridges are sensitive to increased loading past a point that they need. That's not to say that the combination of cartridge and SUT design won't react to different loads due more to HF response (ringing etc) of the SUT. It can be a black art. For a vast majority of today's MC cartridges, a 100 Ohm load or more is very suitable. Higher self impedance low output types may require more loading but that can be calculated. If using higher than a 1:10 ratio for the SUT, this brings it's own set of complications as HF performance, leakage reactance and HF damping can become more critical, as does grounding (achieving a quiet ground floor with increasing gain) and zobel networks are often added to secondary windings in addition to cartridge loading. The only way to get it perfect is to use a scope and measure the results, but if the HF performance of the SUT is known, for the most part, all required values can be easily enough calculated. Getting exact matches can be a little bit of a red herring....it's minimum loading which matters for the most part.

[Pani]

Having owned vintage JS transformers and used a Verto before I bought the (much better, IMO) ST-80SE, I have relevant experience on this matter, so will comment later.

However, Pani, what I'd like to know is why, with a Lyra cartridge, you want to use an Ortofon SUT? Wouldn't you be better with Lyra's own unit, called the Erodion, designed to specifically match their own cartridges: http://www.lyraconnoisseur.com/Produ...n/erodion.html



Marco.

Hi Marco,
The ST-80 is beyond my budget and so is the Lyra Erodion. I have to keep it within $1k or thereabouts. I know that the Lundahl transformers inside the Verto works well with the Lyra Skala because I have used a Shindo SUT in the past which uses a very similar Lundahl tranny inside. Art Dudley had commented that the Verto and the Shindo sound very nearly equal. I was only thinking if the old Jorgen Schou SUTs are better. BTW, I read a post of yours where you have mentioned that you used an Auditorium23 SUT (SPU version). Can you please tell me how does the Verto compare to the Auditorium23 transformer ?

[Pani]

Adding the Bobs devices Cinemag 1131 Blue to the selection now. Has anyone heard it. It has got good reviews in the press, but looking for user experience here.

[Ammonite Audio]

I used to have a Bob's Devices Cinemag SUT, but not sure if the transformers were the same as these, since they had red printing. The Bob's SUT was very good indeed and I regret selling it greatly, but the price is a bit more than it used to be, and is more than a Choir Audio device fitted with the Hashimoto HM3 transformers which sells for $999 - if they are half as good as the more expensive HM7s, they will still be excellent. Bomb-proof build quality goes some way to justifying the price. See http://www.choiraudio.com/Hashi%20sut.htm

That aside, you can buy from Bob's Devices with confidence since he does know how to implement SUTs properly.

[trio leo]

I use a Lyra Delos and other MC's, IMHO the Albarry MCA11 battery powered unit is a superb piece of kit, it just lets the cartridge do it's job, nothing added or taken away and at £500 I think it is great VFM.

Hope you find what you're looking for.

enjoy your music

regards Al