As file resolution goes up sound level goes down?

Thanks Swanny, but my next major upgrade is to replace my seventeen year old Thiel speakers with much more sensitive ones. That will also fix the problem.

I suspect that Swanny's diagnosis is correct. Material that is not as dynamically compressed will have a lower average volume, assuming that peak volume is similar.

You can confirm that by using an audio editing program, such as the free program Audacity, to examine and analyze the sound waveforms of the respective files.

I suspect that what is limiting the dynamic range that can be handled by your system is the combination of a relatively low powered amp and inefficient speakers. If so, increasing the gains, sensitivities, or output levels of upstream components will not help, but changing to more efficient speakers would, of course.

Also, it appears that the 86 db sensitivity of your speakers is specified with respect to 2.83 volts, rather than 1 watt. 2.83 volts corresponds to 1 watt into 8 ohms, but to 2 watts into 4 ohms. Given the speaker's 4 ohm nominal impedance, its efficiency is therefore only 83 db for a 1 watt input, at a 1 meter distance.

Regards,
-- Al

Getting more efficient speakers is moving in the right direction.Kenny you`re making the correct choice if you plan to keep the current amplifier.

Thanks guys, It sure is adding up to new speakers, but the cash isn't adding up as quickly as I like to get there.

Swanney has a good point because my DAC's output is 2.5 volts compared to his 4.5 volts, while my phono stage is high ouput to work with any preamp.

I can try an alternative, as I heard back from the builder of my amp, Sam Kim. He thinks I can raise the gain by adding caps myself. I am pretty good with a soldering iron, so maybe worth a try.

Is the symptom that (a)you can't get enough volume with the volume control turned all the way up, or (b)that you encounter clipping and/or distortion on musical peaks with the hi rez material, at volume control settings that are below maximum?

If the latter, increasing the gain will not help, assuming (as is likely) that what is running out of headroom is the amplifier. The exact same problem would occur, at the same perceived volume level, except that you would reach that point at a lower setting of the control.

Regards,
-- Al