OP,
generally, what volume level is your ARC preamp set at for normal listening?
What about the amp's GAIN? OP's Speakers sensitivity are 94 db/w/m
found this pecking about:
https://www.audiocircle.com/index.php?topic=176890.0
"It might be useful in the specifications section to inform the buyer of what the overall gain of the amplifier is since you are stating that it has too much gain for your 108dB horn system.
The specs state a power output of 6 watts. I am going to assume that this is RMS and also that it is at an impedance of 8 ohms. The specs also state a 400mV input sensitivity. I am going to assume that this input sensitivity is what is needed to pump out 6 watts RMS (clipping).
So let's do the math.
Using P=V (squared)/R; where P is wattage and R is impedance. V then works out to 6.93 Vrms.
If the maximum output power is 6.93 Vrms and to reach that maximum power you need to input 400mV rms (or 0.4V rms), then gain is calculated by:
gain = 20 *dB log (X) where log X is equal to log (6.92/0.4) or 1.24.
gain = 20*1.24 = 24 to 25 dB.
So gain works out to be 25 dB, which indeed might be too much for a 108dB horn system (power being a separate issue of course). I would aim for 12 to 16dB of overall gain in a system that is that sensitive. This is of course relative to what your source (dac, vinyl, others) is producing and if you have a preamp in the system as well. It requires a careful balance.
Pretty amps though! GLWS!
Best,
Anand."
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I've visited OP's home, heard his wonderful system.
One of the issues with the ARC SP16L Preamp is each 'step' in the volume is too much of a jump, not smooth like normal remote volumes. We thought it was inherent to that model, a motivation to change. Are the steps 'heightened' by the amp's gain? Avoid any 'stepped' volume control in an alternate unit?