This may or may not help. I have used a McIntosh 2105 solid state amplifier for years, and I had the same issue. The amp has gain controls, and in an effort to use the preamp (several different ones) at a higher gain setting, I turned down the dual gain settings on the amp. Regardless of the preamp or speakers used, the sound was worse- lack of power and drive, diminished bass etc. It won't hurt you to try for yourself though.
attenuators and potentiometers
I have a wonderful Conrad Johnson Motif MC8 preamp and a wonderful Accuphase P-300 power amp. On all my sources, if I turn the CJ's volume pot up beyond 9:30 or 10 o'clock, it is very, very loud. Often normal listening level is at 8:30 or so, maybe 9:00 for phono. Now I know that volume pots tend to be at their least balanced (l/r signal) at the low end of their range, and I actually think that at lower volumes I sense more coming out of the left speaker than the right, though I cannot say for sure that that is an effect of the pot, instead of the room or some other link in the chain from groove (mostly vinyl) to ear.
Now the P-300 has a switch that limits power output to 50% and 25%. This allows you to use highly efficient speakers safely. It would also allow me to turn up the pot on my preamp. It also has dual level controls. Till now, I have used the amp only at full power, with the output controls to maximum, on the assumption that it's a straighter wire, as it were, that way, so a cleaner signal, than if I use the power limiting switches; also that it would diminish dynamic headroom, etc.. But I am not sure that these are safe assumptions.
So my questions is whether, from a theoretical standpoint, and also from anyone with knowledge of one or more of these pieces, using the attenuation switch on the P-300 should have any effect on the waveform that stands to compromise my sound -- so that it is not just a pure benefit being able to run the preamp volume pot wider open.
In short, theoretically, does using the attentuation compromise the quality of the audio signal?
Speakers are Thiel CS2 2's, if that matters. Easier load than most Thiels.
Thanks!
Now the P-300 has a switch that limits power output to 50% and 25%. This allows you to use highly efficient speakers safely. It would also allow me to turn up the pot on my preamp. It also has dual level controls. Till now, I have used the amp only at full power, with the output controls to maximum, on the assumption that it's a straighter wire, as it were, that way, so a cleaner signal, than if I use the power limiting switches; also that it would diminish dynamic headroom, etc.. But I am not sure that these are safe assumptions.
So my questions is whether, from a theoretical standpoint, and also from anyone with knowledge of one or more of these pieces, using the attenuation switch on the P-300 should have any effect on the waveform that stands to compromise my sound -- so that it is not just a pure benefit being able to run the preamp volume pot wider open.
In short, theoretically, does using the attentuation compromise the quality of the audio signal?
Speakers are Thiel CS2 2's, if that matters. Easier load than most Thiels.
Thanks!
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It's hard to say without having detailed design information on the unit. However, in pro audio circles the phrase "limiter" denotes something completely different than a gain control or attenuator or potentiometer, and I would guess that is applicable here since there are level controls on the unit in addition to the limiter function. What a "limiter" does is to smoothly reduce gain as the signal amplitude approaches some maximum permissible value. While a level control/gain control/attenuator/potentiometer applies the selected amount of attenuation to the signal regardless of the signal's amplitude. So I would suggest leaving the limiter function at 100% and using the unit's level controls to reduce its gain. That may or may not have some side-effects, which you'll have to judge by listening, but I would imagine that they would be subtle at most, while the limiter function (if that is what it indeed as) would have side-effects that would not be subtle at all. Fwiw, I found these specs on the unit: http://www.accuphase.com/p-300_e.htm# Regards, -- Al |
