Any comments on DAC directly to Power amp with no


Do you have any comments of running a DAC directly to power amplifier with no preamp? I can think of several advantages to not using a preamp but would really like your opinion, since, it seems, many of us are opting to go direct these days.

For example, let us assume the DAC goes straight into the power amp's XLR inputs; the DAC's volume control is digital, runs in 32 bits (or 24bits) and is very well implemented.

I have been told that some users do not like the idea of running a volume control well down in its range so use fixed attenuators but many have reported a loss of SQ in the process. Others have stated that they prefer the sound through a preamp stage. And, as expected, others state the sound quality is improved when the preamp is eliminated.

I hope to test these options, with and without the pre-amp, shortly and am interested in hearing about your experiences.

Any comments on this would be appreciated.
hgeifman
I asked my Luxman dealer about the 590ax being "fully balanced" and his response is below:

"Your Luxman amplifier is a fully balanced design when operated as an integrated amp. The connection between the pre-amplifier and amplifier is internal to the unit (it does not make use of the pre-out/main-in connections on the back panel in normal operation). When the 'separate' button is pressed you gain the ability to use either the preamplifier or amplifier sections individually although this does make a compromise of using the single-ended connections (this will obviously not be balanced).

As it will be a fairly rare instance in which you will use the pre-out or main-in functionality it was a reasonable design choice to make compromises in the implementation of this feature (were it done to reference level quality with balanced in and out there would be a substantial amount of additional expense and these larger connectors would take up valuable real-estate on the back panel of the unit, all for a feature that is quite rarely utilized)".

The above answers my question about my Luxman 590ax being balanced. A loaner Bricasti M1 DAC is expected next Wednesday. The question is how will my Ayre QB-9 DSD DAC compare to the Bricasti M1 DAC. I will take the advice above and listen using only one interconnect cable connected at a time (XLR balanced for integrated amplifier and RCA unbalanced for M1 DAC volume controls). This is probably the safest approach.
I ran my dac direct to amps and thought it sounded great until I added a preamp - no comparison in my rig. No preamp meant no midrange warmth and my volume lost too much resolution (berkeley dac and then esoteric k03). You lose res with every reduction in volume in (most) digital volume controls.

08-23-15: Cerrot
You lose res with every reduction in volume in (most) digital volume controls.Cerrot

Only if the Berkeley is below 75% of full output, it's called "Bit Stripping"

Your Berkeley Dac from the specs I saw gives out a massive 6v XLR or 3v SE. And your Sanders Magntec Amp only needs 2v for full output.

If you have to your Berkeley volume below 75% you get the volume down to where you want, this proves you have more than enough system gain without the need of extra gain that active preamp give.

And your Berkeley dac output stage would even have better drive than most preamps have.

So to get a valid idea you somehow need to reduce your system gain so the volume of the Berkely is used at 75% or over.

From what I saw on the Berkeley site you maybe able to change the analogue's amps gain setting from 3v to 2v somewhere (maybe inside)
"Unbalanced analogue output level setting: 3.25Vrms maximum, 2Vrms or lower recommended"

This then should allow you to use it's digital domain volume control at or above 75% of full output which maybe change your opinions about loosing resolution and "warmth".

Cheers George
Hgeifman,

Resolution aside, even if that is not lost, adding a good pre-amp, at least for me in my system :-

1. fleshes out instrument body
2. adds warmth to lean recordings
3. enlarges soundstage in all dimensions
4. adds weight and foundation to orchestral performance
5 improves tone and timbre of instruments
6. improves instrument placement, imaging and separation.

I simply can't go back to not having a pre-amp.

As usual, the proof is in the listening, so to echo what others have wisely said, try it both ways before making a decision.

Happy listening.
Cheers! J.

The "perfect" preamp if there ever has been one, has always been said to sound like a piece of wire with gain, not adding or taking anything away from the sound of the source

And this is what a direct source to amp connection will sound like if done right, adding nothing or taking nothing away from the sound of the source.

If you need to colour the sound to your liking then by all means add a preamp that will do this, but good luck on finding the right colouration, as they all sound different, and it will get very expensive looking for it.

The right way is to change the source, speakers or room treatments to achieve this, to get the sound of your liking, not by adding more colourations.

Cheers George