Dac evolution....

Hi guys,

I open a new topic to have your opinion on the following subject: More and more Dac  (Antelope, Weiss, Benchmark, Auralic, Grace Design, etc....) include now a real preamp. I think it's an important change with pro and con elements.

Pro side :
Preamp is directly connected to the Dac Motherboard.
No more external preamp and cables = better for the budget and the WAF (Woman Acceptance Factor)

Con side :
Does a dac preamp can really perform well ?

So, is it a good or a bad evolution ?

Depends on the DAC, your expectations, and what you wish to accomplish.

IMO, Very few DAC's can replace a world class preamp, but on the same token, if you find a DAC with great volume control (preamp) functionality, it takes a very good preamp to beat it.

Totaldac is the only DAC I have found that has a really great volume control solution. There are likely others, but I have no experience with them. The other DAC's I have tried that fell short in this regard are the Bel Canto DAC3.5VB MKII, Auralic Vega, W4S DAC2. These are the only others I have tried that had volume control, and they did ok, but once you turn them down, dynamics and resolution diminish.

I have read on several occasions that the Empirical Overdrive has a great volume control as well.

I am sure others will chime in with recommendations.

Not all preamp technologies are the same.  Most use active amplifiers which add noise and distortion, some use attenuators, which add noise and sometimes HF rolloff.  The Overdrive DAC uses a different technology, which is actually superior to a separate active preamp or attenuator.  It varies the D/A reference voltage (the height of the stairsteps) in order to reduce the volume.  The S/N ratio actually improves as the volume is lowered, unlike all other volume technologies.

Another consideration is the current drive capability or the output impedance of the analog driver in the DAC.  Most amplifiers require a bit of current in order to achieve good dynamics, so if the preamp in the DAC has excessively high output impedance, this can be a problem with some amps.  Depends on the amp.

Steve N.

Empirical Audio