[rcbarnes]

I am using a delta 44 (though this applies equally to the delta 66) to produce an unbalanced line-level signal that I feed to my Outlaw RR2150 amp which in turn drives a pair of pretty nice stereo monitors I built (with a subwoofer). Is there a particular level I should set the DAC controls to for an optimal overall signal? I don't know if the DACs have some sweet spot that they work best it, whether they distort/clip above some level, or how much the signal suffers from being lowered toward zero.

All my source audio is commercial-recorded, so normalized within standard digital limits.

Also, the Outlaw/Speaker set is a little over-powered for my smallish space, so I live in the lower 1/8 or so of my amp's power when I send it a 100% volume DAC signal. I think I notice some hollowness in when I set the delta's DACs below a certain level, but that might all be in my head. I am much more certain that my speakers and sub lose some depth and relative balance when I turn my amp very close to its minimum, which is sometimes necessary when the DAC signal level is above 7/8ths.

In case it is relevant, I'm using the card on a Linux box and valid DAC level settings are the integers 0--127. I currently have my H/W Out 1(L)&2(R) connected directly to PCM out channels 1/2 (setting up dmix was easier than constantly juggling individual PCM sources---I only ever play one source at a time).

[mgalusha]

100% level on the digital side would be optimal but it sounds like the gain structure of you system is very high making for a too sensitive volume control. Unfortunately digital volume controls drop bits. Not a big deal if they are working at 32bits but at 16bit too much reduction in level in the digital domain will reduce the resolution, perhaps the hollow sound you are hearing.

[rcbarnes]

I don't think my DAC level settings are digital volume controls, so their level should not be altering incoming the bit stream.  Rather, I'm interested in the changing sound characteristics of a DAC at different output levels.

[NewBuyer]

You probably already know this - but when you attenuate your source (either digitally or analog) before it hits your amp, you are usually also lowering your SNR.  I agree with Mike's advice: By your description, your gain-staging seems probably sub-optimal, thus causing your volume control to likely be too sensitive and to stay too far below its optimal level-setting.