Absolute top tier DAC for standard res Redbook CD

Ketch, thanks so much.  I'm not surprised at all.  The OSDE/SE is such an exceptional DAC to begin with.  Steven shared some of the upgrades he did and who time consuming they are.  It's a labor of love, that's for sure.  For those who want to get finally jump on board, getting an upgraded OSDX used is awesome as you can save a few dollars and enjoy a GREAT sounding DAC.  Very cool.

I have been pretty happy with Metrum's Pavane, which bests all the DACs and disc players I have owned or auditioned in my system.  I am interested in Metrum's new Adagio DAC, which reportedly goes beyond being simply a Pavane with volume control.

The volume control on the Adagio is implemented by changing the reference voltage of the dacs, which seems similar to the technology used by Empirical Audio for their volume control.  Metrum has modified the DAC boards and increased the maximum reference voltage by 3 times resulting in a reported noise floor of -155 dB and improved linearity.  The Adagio uses 30VA transformers for each channel  (double the Pavane)  and 16 ladder dacs instead of the 8 used in the Pavane.  

I look forward to hearing whether the DAC with volume direct approach will sound better than sending the signal through the AN tantalum resistors in the volume control of my zero gain, buffered preamp.  It would also be fun to try the Adagio with and without the Final Drive.

I look forward to hearing whether the DAC with volume direct approach will sound better than sending the signal through the AN tantalum resistors in the volume control of my zero gain, buffered preamp. It would also be fun to try the Adagio with and without the Final Drive.

Is the no gain pre-amp a passive or have valves as a buffer? I use a passive (pot and source switch only). It works really week, but the thing to watch is the DAC has;

1 Enough gain
2 The output impedance is low (less than 500 ohms) If it is higher along with capacitance in your interconnects you may get loss of dynamics and bass roll off. 
3 You can sit the DAC and Passive Pre very close to the Power Amplifier

I used to have a very good quality tubed pre-amplifier, but without it is faster, more dynamic, more focussed.

Guido, are you running your Aeris directly to your amps or are you using a preamp in-between? If you tried it both ways, would you share any comments about the relative strengths and weaknesses of each approach?

Sunseekerespana, to your questions:

Is the no gain pre-amp a passive or have valves as a buffer?

The preamp is buffered using solid state devices, very similar to this;
http://www.6moons.com/audioreviews/smcaudio/vre1.html

I use a passive (pot and source switch only). It works really week, but the thing to watch is the DAC has;
1 Enough gain

My current DAC, the Pavane, has an output voltage of 4V, which is more than enough to fully drive the amplifiers.

2 The output impedance is low (less than 500 ohms) If it is higher along with capacitance in your interconnects you may get loss of dynamics and bass roll off.

The buffering reduces output impedance and eliminates loss of bass or dynamics.

3 You can sit the DAC and Passive Pre very close to the Power Amplifier

This is always good practice when possible and particularly with passives.  My ICs from preamp to amplifiers are I to 1.5M.  When I compare my buffered preamp with a passive preamp I own (Goldpoint) I never use longer than 1M ICs.  I also have Endler attenuators, which connect directly to the amplifiers and actually sound pretty good.

I am curious about the variable voltage volume control in DACs like the Overdrive SE/SX, Aeris and now Metrum's Adagio, and whether those have any negative effects (relative to usking a preamp) on things like bass impact, dynamics, staging or other desirable sonic traits.  I was worried about these issues when I went to a zero-gain buffered preamp but it seems to be the best of both worlds with excellent bass and dynamics plus the clarity/purity passives are known for.