why so many benchmark dac1's on audiogon?


I am looking to upgrade my digital front end

my phillips transport Audio Aero gave up the ghost and is too expensive to fix

I bought a nice audio research cd2 - may use it as a transport

I eventually want to go to an alesis masterlink or tascam or other and do 24/96 recordings off my analog rig

I read the sterophile review, see a lot of the benchmark dacs here on audiogon.

I would be interested in the usb version
the pre isn't going to be as good as my dedicated pre

any comments on why there are so many on audiogon?
good sources to buy from?
would want cd and usb inports

I'd prefer the black model
128x128audiotomb
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1. Lots of interest and users of Benchmark because it represents a good value.

2. Not all Benchmarks are the same. My understanding is that the design has evolved and older Benchmarks may not be up to snuff with newer and it may be hard to tell exactly what version someone is selling. So there may be some risks associated with knowing what you are getting when buying used.
Also, DACs are hot these days for use with music servers and as sound upgrades to many players and BEnchmark is one of the hottest and most affordable good units, thus the large # units circulating.
There was another thread like this recently. Perhaps people are upgrading to the USB version and selling the older DAC1. Certainly the newer USB version and preamp may make the conventional DAC1 seem more dated.