Dedicated phono-pre for MM only?

Axel, you and I are thinking along the same lines, save for the fact that I would not use a transformer anywhere. The desire for a balanced circuit is a real sticking point as almost none of the commercial products offer that. There is the Aqvox, but as far as I can understand from their very confusing ad copy (where they say in one para that it is balanced and in another that it is SE), the balanced circuit, if present, is used only for MC cartridges. If you use the MM inputs, the circuit is SE. The ad also contains some mumbo jumbo about MMs being voltage generators that prefer a SE circuit topology (as compared to MCs). I don't "buy" that logic. The new K&K phono is I think balanced, and I intend to look into that one.

The IC design is interesting, but the ICs used have been surpassed for audio in recent years; I am wondering whether one can just plug in one of the later better sounding ICs, without a re-design.

Herron Audio makes a tube MM Phono Pre-amp. I have not heard it, but I have been using their MC Phono-pre for a number of years (on my second set of tubes), and I have never (yes, never) heard one that was better. As with all things audio, YMMV.

Dave

Correction:

I just checked Herron's site and they have discontinued the dedicated MM phono-pre and now have a combination MM/MC with variable loading provided by changeable plugs.

Interesting looking answer to a common concern.

Hi Tom
you ask:
>>> Do you think that a high quality SUT or headamp could provide the gain and loading needed to turn a high end MM stage into a high end MC stage? Or does the use of external transformers or headamps degrade the signal too much to be considered acceptable for a high end phono stage? <<<

To start, a head-amp will be (generally) providing the lesser quality, compared to a good SUT.
(That's why they fell out of favour, years back already --- and today? ~ No need...)

Now to the SUT, and here I guess it will..., become controversial once again?

It is my current experience that a top MM into a good MM(MC?) phono-pre will beat an MC with an SUT into that phono-pre. Given, that we have a top class match between MC and SUT, and a subject all on its own.

Only, and only, if for various reasons of your own, you love that MC, and that low gain phono-pre (and particularly if its a good one!), would I consider the SUT option.

It will not be a bad mix by any means. You'll have more dynamic depth, more bass punch, a bit more harmonic completeness, compared to MC only... so, nothing to scoff at.
Yet a good MM will very likely do it all with a bit more 'EASE', so far what I have found.

I still think, that most (if not all phono-pres just have to try too hard to get most 'everything' from that puny ~ 0.3mV cart voltage into a harmonically complete reproduction OF WHAT IS ON THE VINYL.

Now offer that phono-pre ~ 5.0mV it is just simply easier to get it right, as close as can be. And that in turn applies to the MC plus SUT match, ... with maybe a little less ease.

What will go missing with the MC / SUT setup is some micro detail swallowed up by the SUT's leakage inductance, parasitic capacitance, etc. it can be noticed by a less sharply carved out image presentation -- some would argue is unnatural anyhow (like stuck with your head in the microphone).
Yet, plenty people find that's what's needed, else it does not qualify for 'Hi-End' and I'm not going to argue...

Now all the electronic fundies are gonna jump up, but counting ELECTRONS (in a phono-pre) literally, if you consider micro-information coming from the vinyl by 0.3mV, 5cm/sec @ 1k Hz is actually one MIGHTY tall order, 'cause a lot is a the 'single electron' level before it is 'pumped up' and equlised. One electron gone missing = information lost.

I hope this answers your question.

Greetings,
Axel

Funny that no one has mentioned the new Passlabs XP-15 as yet.
It's SS, but seems to be close in a number of other 'parameters' mentioned. Good price too $3'800...

Any comments?
Axel