ACCUSTIC ARTS TUBE DAC SE 11: how smooth it is ???

i read a lot of treads regarding this dac but how it compare to the best?
Any owner to find it edgy ? wich brand are the stock AX7 tubes use in it ?

There is the verdict of an HIFI CHOICE review:

"If there is anything to criticise, it's a very slight degree of hardness in the highest registers when reproducing instruments with an extended harmonic structure - a violin being perhaps the most critical. In such cases, the 'air' around the instrument is not quite so pure, the decay at the end of notes a touch less well-defined."

Was that sound come from stock tubes or a mismatch with the rest of the system??

Any opinions from owner are welcome
I have Wp7's which are very sensitive to edgy high frequencies. I feel the Tube DAC with Ampex Buggel Boys sound extremely smooth, full bodied and transparent. I can't remember how it sounds with the stock tubes but you would want to change them anyway.