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DAC as a preamp?

I need a new DAC. I use my computer for volume control, but do not trust it. I want separate volume control. The 90s me would have immediately thought preamp. But since I need a new DAC, my question stands ... DAC as a preamp?
I've posted more info about my system below.
I need some advice on the best way to go about getting volume control for these powerful asp1000 amplifiers. I've read about the high input impedance. I use a computer for my source playing Flac, wav or hi-res audio files. I'm using a very simple dongle Style USB DAC that sounds okay. I have choices, but do not know what my best bet is. For simplicity, it would seem I should just buy a better desktop DAC, such as and SMSL M500 and use the volume control knob on front. Or ANY other DAC with a volume control for that matter. I know I can use my volume control the USB. Provides through the keyboard on my computer. But with amplifiers this powerful, I figure I should have a volume control to prevent issues such as full volume noise blasts, which have happened before when the computer glitches. My second option would be to purchase a regular preamp. This would be the most expensive option, as I would want something at least as good as the Schitt Freya +, and that is $900! I would still need a decent DAC upgrade. This gets expensive with my health issues at hand. The last way I could go, is something like an all tube gain stage. I would still need a DAC, but a simple gain stage kit should only be a few hundred at most. The other two options I can think of, would be the pass B1 buffer clone kit preamp for 150 dollars, but I don't know if it would play nice with a high input impedance of the icepower amp. The most simple and cheapest route, would be be using the Sure digital volume control option. But I do not know how high fidelity that would be. I could really use some help. I've been out of this hobby for about 10 years now. I feel a bit lost and appreciate everyone who has helped so far.
flaxxer
georgehifi's avatar
georgehifi
10,312 posts
 

@georgehifi, would there be less impedance variability with a DAC’s digital volume control than through a typical passive analog volume control?


Yes the output impedance would remain constant and lower with a digital domain vc what ever the ss output buffers (opamps) impedance is, usually 100ohms or less.

Where with an analogue one if the vc is on the output after the output buffer (opamp), it would vary a bit, and if 10kohm in value, be suited better to amps with input impedances of 33kohm or higher.

If the analogue vc is before the output buffer it would then need more complex circuity, and an input buffer (opamp) as well, as the I/V stage or da chip would need it, the output impedance then would be constant and low as in the digital one. (but this way there is an extra (opamp) buffer in the signal path, I don’t like that)

The very best is what Wadia did with their flagship CDP’s and DAC’s, use a digital domain vc but with analogue stage gain setting links inside so you set the digital vc to be used in the top 25% of full volume into that system, so there’s no chance of "bit stripping" They state this in their setup user manulas that it's the best sound to go direct into poweramp, using this system

Cheers George


unsound
7,341 posts
 
@georgehifi, Would that in turn mitigate the interconnect capacitance concerns associated with passive analog volume controls, allowing for greater choices and useable  lengths for interconnects?
alfa100's avatar
alfa100
222 posts
 
Simple answer.  DAC with built in preamp is way to go.   I’ve tried super preamps but prefer my MSB DAC direct to power amp. It also has analog input for my Phonostage 
flaxxer OP
76 posts
 
As the OP, I pray my D90s volune control is in the perfect place for proper gain, but I doubt it. 
I do NOT want to bit strip after paying $750 for the DAC.
Why use a Schiit buffer for $49, when a Pass clone is $150? Or a Marantz 7 clone for $400?
What makes one buffer better than another, if all they do is attenuate?
AND I need remote control too.
unsound
7,341 posts
 
@flaxxer, technically the $49 Schitt is not a buffer. A buffer is an active stage without gain. Schitt offers a buffer option on their more expensive units.
Why are you so doubtful? What is the input sensitivity for full output on your amp? 
The standard output of 2 Volts single ended and 4 Volts balanced of your new DAC would work with most amps. The DAC has 32 bits, the highest commercial rez media uses 24 bits, and in practice the maximum number of bits used is 21. One can usually expect about 12 dB attenuation per bit. You'll probably have plenty of bits to spare before bit stripping occurs. Again, if you do need further attenuation you can do so without the redundancy of extra volume controls with attenuators such as the Rothwell's;  
Attenuators (rothwellaudioproducts.co.uk)

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