CAL Alpha and an Equalizer

Hi again all,
No, I think the transport is fine, has always worked just fine. Sure, I'll agree, and won't debate there's probably 100's of transports out there that will easily best the CAL Delta I have.

Running a search through the archives on the CAL Alpha, and various Tubes, I did come across a post from Zinfan (Tom) who remarked that the Mullard CV-4004 Tube in his own CAL Alpha DAC was "un-involving", or something similar to this effect, and I believe I'm noticing perhaps the same thing, as these may be the exact same Tubes Tom was referring to. He, in fact "gave me free!" a set of the Mullard CV-4004 to try, and I'm betting that these are the exact same pair he tried, and didn't personally care for.

As others have mentioned in older threads about the Alpha, these particular Units seemed to be a bit more sensitive to Tube Rolling, and as Tom has found, the Sylvania 5751 3-Mica Black Plates were the very best choice he found.

I don't doubt him on this, but truthfully, it can start getting awful expensive with experimentation with Tubes, even these small signal Tubes, and I sure wish I could find a relatively inexpensive alternative to try, without blowing a virtual week's pay for a pair of tubes! :-)

I was honestly thinking of trying again, the el cheapo Sovtek 12AX7AWPS just for the heck of it, but in truth, I read some mixed comments about these, both good, and some not so good.

At least with the JAN-Phillips 5751's that were in it before, dynamics, involvement, and Bass seemed a bit better at the expense of highs that seemed to be a bit too glassy, and "screechy". Mark

I believe the Alpha's output voltage by default is 4V, and is adjustable by replacing resistors. Sometimes there are benefits to having a high-output CD player, as I found out using a low-powered integrated.

If you want to try different tubes on the cheap, I would recommend the JJ's. They're very inexpensive. The downside is that JJ's are known for a more "lean and detailed" presentation; this seems to be what you're trying to avoid. Maybe EH instead? I tried Sovtek's and wasn't thrilled with them. But nothing compares to the Sylvania 5751's in my experience thus far.

Good luck. I think the Alpha is a great DAC for the used prices we're seeing now, and it's been in my system for over 5 years now; nothing else in my rig has had that kind of staying power.

Michael

I've used both old and new Tesla's /JJ's, EI's, EH's and Sovtek. EI's had a very smooth top end neutal/warm mids, but not strong bass. The JJ's were as Michael described and not very sturdy. The EH's have a full bass and were fairly neutral thru the mids and highs. I was expecting them to be bright and etched. They were not! The Sovteks were cold and enimic. Bottom line I'm using EH's in both units.

Hi Newbie, You mentioned brand, but not number of Tube?
I assume by "EH", you are referring to Electro-Harmonix, correct?

Is it the 12AX7 EH you refer to?
Of course too, there are a number of different model Sovtek in 12AX7 (3 I believe?) Was it the Sovtek 12AX7LPS you tried?

I've seen some new NOS Sylvania Gold Brand 5751WA 3 Mica BlackPlates w/Square Getter on the net somewhere, but asking price is $140ea, and I'm thinking that this is a bit out of line, regardless how nice they are! Thanks, Mark

Mark,

Electro-Harmonic 12AX7EH. The Sovteks were the 12AX7LPS (a lot of folks seem to like these, I find them bright and I had three early failures as well) and the 12AX7w?? which were junk and I threw them out. Regarding the high priced NOS, Ive used very little of it. I've just got too much tube stuff to maintain and if I started using them in all my stuff I'd go broke. On those few occasions I do they find their way into tube phono and line stages where they can make a much bigger impact. One good thing about the Cal units though, they aren't hard on tubes - you get a lot of life out of them.