CAL Alpha DAC: Stock vs. 24/96 upgrade

Ckoffend, I don't understand what you're saying. Please explain in more detail. Thank You!
Kevin

I think the mullards have very smooth mids and really clean, crisp highs. Telefunkens seem to get a little better bass. In my experiences, 5751's rock a little better. They do not smooth over any sound. 5751's can handle more plate voltage which is why the can "crank" a little more. CJ pre-amps always came with 5751's and I hated it. They would cook mullards but I felt they sounded a little more "tubey" with mullards in them (I've had a PV-5, PV-9 & PV-10).

Yes, I tried the Mullards in both Alphas with very pleasing results. If I had 3 sets, all my Dacs would have them. The Telefunkens and Mazdas have more air in the highs but the Mullards vocals are crystal clear (most of my music is vocal and acoustic). I have not heard modified players compared to the Alpha but saying they "crush" the Alpha may be pushing it. The Alpha is very hard to beat for the money. Plus with the next wave of audio being music server based, a nice tube DAC will come in handy. My neighbor already uses his SigmaII with an AppleTV in a 2 channel set up with Dali Helicon 400s and a Prima Luna Dialoge integrated. WOW! Both audio and video are outstanding. Plus the simplicity of a music library at your finger tips. I am planning on that next leap with my systems (which is why I have 3 Alphas).

Buda, When I read your posts you sure do make a case for the Alpha. As stated before, I'm still getting used to it. It really does have some characteristics I like a lot. I also own a CAL Icon Mk.II Powerboss which I really like too. Of course, I'm finding it's a different animal than the Delta/Alpha combo. I will probably tube roll before I decide on the 24/96 upgrade. I don't want to spend too much on tubes but it would be a good idea to at least try some out. Thanks for your help.
Kevin

I tried the Mullard's and didn't like it. Very syrupy, lacking in details. The Sylvania 5751's, though, provide a very clean, full, airy sound that was a revelation. I agree with the idea of playing with tubes before you throw down $500 for an upgrade that you will never be able to recover.