CAL Alpha DAC: Stock vs. 24/96 upgrade


I recently purchased a used stock (I believe 18-bit) CAL Alpha Tube DAC. I'm considering the 24/96 upgrade. Those of you who are familiar with the sound of both, please weigh in. Also, tubes that you like with either version, what sound do they produce? My DAC came with the Eico/Mullard brand 12AX7/ECC83. Thank you in advance.
routeman21
How are you planning on getting the 24/96 upgrade? To my knowledge, that hasn't been offered since 2002-ish, since California Audio Labs has been out of business for several years.

As for the tubes, my favorites so far are the Sylvania 5751's. (It's a lower gain version of the 12AX7.) Not cheap, but definitely a big upgrade putting those tubes in.

Michael
Michael, I emailed Approved Audio Service in Litchfield, CT. They emailed back and said they can do it for $500.00 + shipping.
Kevin
Routeman, I considered doing this myself as I had a Cal Alpha original DAC. The general feedback that I received on this same mod (about 15-18 months ago) was some liked it better modded and others didn't.

Overall though, the concensus was not to pay for the upgrade but instead to just buy the 24/96 version and see which you prefer. Sell the one you don't like more. The difference in value between these two DACs is only about $150 (then, 15-18 months ago), so based on this, it is more cost affective approach.

FWIW, I never got the 24/96. I eventually went with a Kora Hermes (which I loved). But that Cal Alpha is a great DAC, especially for the price! Be very careful when shipping that unit, you need to place a piece of foam on the transformer to support it. It has a tendency to crack at the connection point and then you have a couple hundred dollar repair.
Ckoffend, How about that! I never heard about supporting the transformer when shipping. Thank you for that info.
Kevin