Carver Raven 350 Amps

jond,

I'm a rebel... 
No, I like the sound of Planar and Electrostatic speakers but I know my current amps wouldn't work with them. It will be hard to part with my Atma-Sphere amps though because they sound so good.

ozzy 

ozzy that's cool so what planars or electrostatics are on your radar? With that much tube wattage you could pretty much drive anything.

jond,

There are many including the Sanders, Magnapan, and the Martin Logan. All are difficult loads to drive.

ozzy

Question:

I have noticed considerable hiss coming from my speakers with the Carver amps. When I turn off my preamp the hiss goes away.
So, I’m thinking that the hiss is not coming from the amps but from the preamp or other upstream components.

My DEQX preamp has adjustable input/output settings that have not reduced the hiss. There are also internal jumpers to increase/decrease the preamp output but at this time I have not changed them.

I do not hear this hiss when I use my Atma-Sphere amps.

erichgs, dracue 1, or others, any suggestions?

ozzy

@ozzy 

Are the Atma-Sphere amps entirely quite (put your ear right up next to the tweeter on the driven speaker and see if you can hear any hiss)?   The gain on the Carver 350 is 30db while the gain on the M-60 is 20db.  Do you hear the hiss if you set the carver volume knob to 2/3 (not sure if this knob is volume (output stage) or gain (input stage))?

 I am no expert but did just spend two weeks researching and troubleshooting a hiss/buzz issue in the amp the Carvers are replacing and from everything I read if you remove the inputs (in many cases the recommendation was to short the inputs) and noise goes away it is almost certainly not an issue with the amplifiers.  The trick then is to find the offending electronics.  I didn't know this up front and ended up spending hours of trying different things before finally just isolating the amplifier entirely on a single outlet circuit with all the other breakers in the house turned off and the inputs on the amp shorted only to get the same buzz.

Since you have already determined unplugging the pre-amp stops the hum, maybe start by eliminating the pre-amp and driving the carvers from your sources one at a time and see if one has a buzz while the others don't.

Erich