Digital gain vs analog gain

Already useful. Had a little time today for some ear tweaking. iTunes slider at 0dB, preamp analog pot at 12 o’clock, Crown attenuators at 8 o’clock. As compared to my previous setting, Wharfedales were more forward, tweeter a bit brighter, bass tight and rich. Unscientific impressions were that the signal was more complete without noticeable distortion. Less relaxing but more engaging LOL

My initial question is well solved thanks to this discussion. The practical info about gain helped. With the analog preamp pot at 50%, iTunes slider at 0 db, and amp at 25% attenuation everything was more forward at a final volume comparable to before my question. Before, with the slider low and preamp pot way down so the amp could run at 100% it seems I had it all backwards…starving things out and pinching the signal to noise ratio.
 

Biggest proof? The amazing difference from my Wharfedale Lintons that I can induce at this new setting just by sliding the iTunes level between 85% and 100%. Volume changed just a little, but mid and treble imaging exploded in a good way every time I took it back to 100%!

I am not suprised at your findings. I have always been advised that one should set iTunes at full volume. Then set amp such that your preamp can be run between 10-2 o'clock depending on desired volume ( therefor around 12) . This is usually the sweet spot on most variable pots used in a preamp. 

One problem you have is the total gain you have between preamp and amplifier causing you to attenuate much of the available gain in the amplifier. Your compromise seems the best fit. 

Then set amp such that your preamp can be run between 10-2 o'clock depending on desired volume ( therefor around 12) . This is usually the sweet spot on most variable pots used in a preamp. 

Data?

I have always been advised that one should set iTunes at full volume.

Compression is LOW-FI See ieLogical Lossy for a real life iTunes example

Lossy music on a high resolution system can be literally nauseating due to the constant atemporal image shift.

Two things.

First, my listening enjoyment on a system costing only $2K between a recapped old Crown PS200 and the new Wharfedale Lintons, a Bluetooth DAC and unpowered preamp switch with a pot has benefited from all this info. 

Basically, pushing in higher level digital and living with analog attenuation of 50% at the preamp and 25% at the main amp has pleased the clever Peter Comeau designed heritage speakers and delivered more detail to my listening. So thanks!

Second, I’m interested in the issue of lossless iTunes format from Apple. My little BlueMeHD Bluetooth DAC combination is a well reviewed accessory for older amps, and seems to compare well to the more expensive TASCAM CD400U rack Mount in my other stereo downstairs in our living room.

My best reading so far, however, sounds like Apple does not say that their format survives Bluetooth transmission. I have a couple iPads snd I could potentially rig one of then as a hard connected high speed WiFI input device. Is that worth a new thread?