Stand out phono stages

My Audio Research SP20: $9000 is a full-function, line-plus-phono preamp. And offers a headphone output—the new SP20 is a pure class A and sounds better than any phono preamp I have heard to date.

All preamps are class A FWIW.

It's been some time,but I added a Lightspeed Attenuator and now run the Manley steelhead in fixed mode and just as a phono stage.

Much better, than running it in variable out into the amps.However doing so eliminates operating it in mono.

The phono stage really opens up and is cleaned up getting rid of the built in volume control.
It's a nice feature and I used it as a pre-amp also,but sonically the LSA is the way to go,even if I have to use a set of interconnects from the Manley to the LSA.

One other thing that I've found out about the Steelhead.
Run at 50 ohms for a Clearaudio Talisman v2,I get much better bass and sound than I did running the MC at the extreme other end the loading closest to Clearaudio specs.
I used to think that the often quoted 100 ohm was also better, but even lower really does the trick for me.

Truth told, Manley suggests you play around with the settings,nothing is written in stone.

Also, I did run the Clearaudio MC in the MM input,but prefer it in the MC loaded down to 50.

There's more full bodied sound this way, more to my liking, and no noise issues.

The Steelhead is a good phono/pre as is.
For me it's function is as a phono stage,and I think that's how it should be judged.

Ralph (Atmasphere) wrote:

>All preamps are class A.

For discrete circuits, this is true. OTOH, the vast majority of opamps only have a very small output range in which they run in class A. If the signal amplitude exceeds that range, the opamp's output circuits will shift to class AB operation. This is because opamp manufacturers place great emphasis on energy efficiency, and therefore internally bias their output stages in a manner that keeps the standing currents quite small.

That said, it is possible to keep many opamps in Class A operation over a larger range by connecting a current source (or even a well-chosen resistor) from the opamp output to one of the power rails (which rail works better depends on the design of the individual opamp). However, this "forced" Class A operation needs to be implemented by the preamp designer. I have seen many opamp-based preamp designs (and DACs) where Class A operation was not implemented.

kind regards, jonathan

The new stage by Clearaudio may well be a game changer - amplification in the headshell before going down the arm - has anyone heard one yet?