[Stereo Skunk]

No. I'm obviously not talking about volume-wise.

I can turn both gain i and gain ii down to 0, and bring them up to listening volume, but gain ii sounds 'firmer'. The character is changed pretty obviously.

Is this a function of negative feedback in the amp or some circuit that's necessary to get to higher gain?

 

[NA Blur]

What headphone / speaker are you listening to? If you are listening to a dynamic headphone then one gain setting may have higher impedance adding a touch of bass bloom. In most instances they should sound the same if you take care and match the SPL at each gain setting. It may also have to do with the range of the volume pot. There are often non-linearities in volume pots at the early sections of the range. On gain level 3 for example you may only use 1/10th of the range for some headphones placing the volume pot in that non-linear area.

In the end I think it is purely a SPL issue. At gain 2 you are setting the volume to slightly higher volume. Higher SPL is often perceived as better sound.

How are you ensuring that the SPL is the same using each gain setting? I use an SPL meter and often find the gain settings sound the same.

 

[Stereo Skunk]

I didn't ensure that SPL is the same... unfortunately I have little interest in doing so.

The character is maintained through the volume knob travel. I can crank gain I and never get the same 'firmness' as gain II at lower volume level. No. I'm not claiming the 'firmness' is desirable, or sounds better.

I think you could be onto something with impedance. Unfortunately Drop didnt' publish anything on how the various gain settings measure. Nor did Amir measure on different gain settings, either.

It sounded like gain I was less compressed than gain ii. It's gotta be something in the circuit, even if we chalk it up to component nonlinearity. Could it be that gain ii has lower output impedance, giving more damping factor at the same output volume? I'd almost put my money on that. Do amplifiers lower their output impedance at higher gain?

 

[bigshot]

Humans tend to think that slightly louder samples sound better. You need to level match to compare with any degree of accuracy. That is basic.

That said, "firmness" is a very vague description. Can you be more precise? Is it dynamics, frequency response, distortion? Analogies don't communicate well. Can you record it and hear the difference in a recording? You could do that and post it and maybe someone would have an explanation.