Berkeley Alpha Reference run direct


Has anyone found a preamplifier that improves the sound from a Berkeley Alpha Reference DAC? If so, what preamp? Mine sounds amazing feeding my amplifiers direct, DAC to amps.
imgoodwithtools
The key, to me, was the loss in resolution with a digital volume control.  You really need to compare it.  Volume reduction should not be a loss in resolution.  
Certainly a big difference of opinion here:

joeinid:  "With a preamp, you might get a slight loss of detail…"

cerrot:  "The key, to me, was the loss in resolution with a digital volume control."

I always thought the terms resolution and detail referred to the same thing.  

Yet both posters want to use a preamp.

So, which is it?  Please enlighten me!
We all hear differently. Let me say it this way, DACs direct to amp have more "detail" but I find it more fatiguing in the long run. Digital attenuation reduces the volume by throwing bits of data away. That's why some don't like it. For me, the better the preamp, more gets through but still retains the musicality that I love. 

A dac direct to amp seems impressive at first, but too much detail takes the enjoyment out of it.

Have you compared a preamp to no preamp in your system? If you love no preamp, great, you've saved some money. I've compared it many times with several dacs and many preamps and I always prefer the preamp. 
It's a known issue that digital volume controls reduce resolution.  The higher priced models claim to solve the problem.
One factor here might be the sensitivity of the amps used. With my BAR feeding the Ayre amps, the volume control is usually in the 45-52 range. Berkeley recommends a setting of 54 if connected to a preamp, so I suspect I'm losing little data at that level. If run thru a pair of LAMM amps, my BAR volume was down around 32-34. I definitely preferred preamp when listening to the LAMMs.