MC phono stage without transformer?


A newbie question:

I read a lot of 'reservation' about using an external MC step up transformer to increase the gain of an MM phono stage. But as I searched around for MC phono stages, I noticed that a lot of these actually have internal step-up transformers, some of these transformers are exactly the same as what some people used to make their external step-up.

So if transformer is no good, I should really be looking for an MC phono without the tranformer? Do these exist though?
viper_z
Hi Viper,
What's left over from my old system is a vacuum tube Supratek preamp with built in phonostage that will drive a MC cartridge with a output voltage as low as 0.2 mv WITH OUT the use of step up devices.

The Chenin model are quite good and would be very difficult to beat, if at all for the used selling price.

Keep an eye out for a used one, stock unit prefered, totally unmodified.
Their web site is still up @ supratek.biz/preamp.htm
Dear friends: I come back on the RIAA eq subject because there is a subject of critical importance where almost no one ( and I say " almost " only because I don't read any single post on Agon but the true is that I never read nothing about. ) speaks on and that it is almost important as is the accuracy on the RIAA: inverse eq.RIAA interchannel deviation.

What this means?, well in a Phonolinepreamp or Phono stage we have the RIAA for the left channel and the one for the right channel. In a perfect world both must be exactly the same ( mimic ), any deviation between them degrade makes a signal degradation in many ways and yes you can hear it.
Take a look to some Phono stage measures through Stereophile on the RIAA subject and in all of those measurements ( SS or tube ) exist deviation between left and right channels RIAA curve of 0.1db ( for say the least ) and higher.

Now, we have to have not only " matched " inverse RIAA eq. curve channels but at the same importance level we must have both channels with the same gain, 0.1db of gain difference between channels well makes a " difference " in the performance and leave us faraway from the recording.

So IMHO are ( at least ) three critical areas to make justice to the recording through a Phonolinepreamp: inverse eq. RIAA accuracy, no interchannel deviation on the inverse eq. RIAA curve and matched gain in both channels.

As any one can see the Phonolinepreamp ( RIAA ) is truly a complex subject and a true challenge for any one that try to be near/truer to the recording.

Why am I posting about?, well because those subjects are IMHO of paramount importance and ( if the design take in count with care. ) make a great difference in the quality sound reproduction/performance .

Regards and enjoy the music.
Raul.
Dgarretson wrote:
All things being equal in the phono section, are .1-.3mV MC cartridges inherently superior to .4mv and higher cartridges, more cost-effective, or both?
Inherently superior? Yes, if we're comparing two cartridges of otherwise identical designs (e.g., a high output and low output version of the same model). The LOMC will have fewer coils on the armatures, which means lower moving mass, which results in faster rise and decay times, better responsiveness to small modulations and greater peak amplitudes.

Of course actually hearing all this theoretically superior performance requires that the rest of the system be fast and resolving and dynamci enough to push the speed, detail and dynamics through the speakers.

That all sounds like good theory, but is the superiority real? No question about it IME. I've compared high vs. low output versions of the same cartridges from both Benz and ZYX. The differences are always audible, and the better the cartridge the more it seems to matter.

More cost effective? Tough question, and the answers depend not just on one's finances, but also on one's ears and sonic preferences. Those who love rockin' to the solid sound of a good MM might think it a waste of money. Those who get goosebumps from the shocking realism of a great LOMC will gladly spend the money if they can. I don't think anyone could answer this question for anyone but themself.
Doug, my question arose primarily because of the many posters to AA Vinyl Forum who are enamored by relatively inexpensive LOMC Denon and Dynavector cartridges in combination with inexpensive Cinemag step-ups. Though I have not tried such combos, I'm curious whether they represent a free lunch relative to higher output cartridges through all-tube phono sections with moderate gain.

Closer to SOTA, the question comes down to whether very LOMC are best served by step-ups, or by one of the few top SS or hybrid phono stages that can provide circa 70db gain.
Obviously a limited budget must make compromises. Even the best transformer, perfectly tuned, will reduce peak amplitudes, flatten waveforms and lose low level detail; it's an inevitable consequence of passing an electrical signal by induction. OTOH, a HOMC also reduces peak amplitudes, flattens waveforms and loses low level detail, but for mechanical reasons rather than electrical ones. (The third choice, an LOMC + inexpensive active gain device will also compromise the sound, though in different ways depending on the device.)

Which is least bad? As usual, it comes down choosing the sonic compromises which work best for your ears and system. You can do this the easy but potentially expensive way (buy different stuff and compare) or the hard but less expensive way (develop a strong internal sense of what sounds right, figure out why, then move continuously toward equipment that brings you closer to that goal for reasons you understand). There's no prefab answer to your question IMO. :-(

SOTA is a different matter. It cannot be attained with any transformer we've heard (5 or 6 in all). Core saturation is one audible problem, though it can be somewhat reduced with good materials. Ultrasonic ringing and its audible zone harmonics are another, though they can be tamed with a Zoebel network. What can't be eliminated are the reduction in peak amplitudes, flattening of waveforms and loss of low level detail. Once the rest of a system reaches a certain level these effects become noticeable, especially if you have a SOTA high gain phono stage handy to compare.