[miklorsmith]

Yes, DAC, but not AVA.  The OP had no hope of getting an answer to this question if it was limited to an AVA DAC.  The original question was not couched specifically to the AVA brand.

I think you've closed the loop as to why upsampling to 24 bits can be desirable in a volume-control context.

[modular747]

The OP's question was whether the Van Alstine DAC required a 16 bit source was simply answered: YES.  Your discussion of the inner workings of your preamp, which is not a "source" at all, was irrelevant.

24 bits is "desirable" for a digital volume control in the same way it's desirable to be punched in the face with a gloved rather than bare fist.

[miklorsmith]

Wow, you have anger issues.

I see you are correct that the question was regarding an AVA DAC, my apologies.  However, I do not see where the question was answered simply "yes, the AVA DAC requires a 16-bit source".

The OPs question was specifically related to a post I wrote, so I'm sorry for trying to clarify.  And, for the purposes of serving digital bits to a DAC, my TacT is a source in every meaningful way.

Your Opinion about the potential benefits of upsampling to 24 bits to preserve resolution is undermined by your own quote below:

Also, digital volume controls work by "bit stripping and shifting" - progressively lopping off the least significant bit.  In a 16 bit system, a 36 db attenuation reduces the signal to 10 bits.

Starting from a higher number of bits would give the opportunity to have more "least significant bits" to throw away.

I've observed before and it is certainly appropriate here, strength of rhetoric does not equate to strength of position.  And with that I leave you to your dark and angry place.

[TjMV3]

24 bits is "desirable" for a digital volume control in the same way it's desirable to be punched in the face with a gloved rather than bare fist.

That was the best line I've heard in weeks

Uh...don't mind me.

[avahifi]

Digital volume controls work by throwing away bits!   

Just what everyone needs for higher fidelity. 

Geeze.

Of course if you use a wonder digital cable, you certainly will be saving those few remaining bits you have left I hope.  Yah sure.

Lets hear it for Enid Lumley and microcracks in her turntable platter bearings because of digitally recorded source material for her LP records. She certainly would have been happier with fewer bits because then there would have been fewer cracks, unfortunately not including the one between her ears.

Frank Van Alstine

[modular747]

Wow, you have anger issues.

I've observed before and it is certainly appropriate here, strength of rhetoric does not equate to strength of position.  And with that I leave you to your dark and angry place.

This is the second time you resorted to a personal attack when you couldn't knowledgeably and rationally defend your position - not surprising. The problem is that you are unable to rationally evaluate  "strength of position"...