CAL Alpha and an Equalizer


Hi all, Hope you can please bear with me through this post to explain my findings, and a possible solution?

About 5-6 months ago, I bought a mint CAL Alpha DAC from another A-goner here, and have posted before, about its characteristics, and sound.

I don't believe there is anything specifically wrong with it per se, just typicaly Alpha sound.

Well, first thing I did notice when replacing my long owned CAL Sigma II DAC, was a very "lean" glassy, analytical, and very hot sound, like the DAC was hitting my Mac Pre-Amp a bit too much on the hot side.

I have bought a pair of Endler's 12 Step Attenuators, and that solved the hot output, but it still sounds a bit lean. Can an EQ be inserted between the DAC, and Pre-Amp? Mark
markd51
Hi all again,
I've come to this realization about the Cal Alpha (through the archives) and perhaps other equipment like this, that shares similar qualities.

Tube rolling is the key to suitable sound, but one sad fact, is that if one wants to put in a pair of NOS Sylvania 3-Mica BlackPlates with D-getter, be prepared to pull your pants down.

I just bought four c-9 version Shuguang-Sino 12AX7 tubes to try. In all honesty, they might be better than the crap shoot buying "supposed" NOS tubes from the online scalpers. Mark
Mark I have to agree with you regarding the tubes. I have had better luck using current production tubes than NOS stock in my Alpha as well. I do prefer NOS 12AU7’s and 12AT7’s to current production types in my other gear. A few years back I had an Alpha, which I bought here and it came with Golden Dragon’s. The printing on the tubes was very detailed, unlike some others I have seen lately. They may have in it for years before I got it, who knows? Those were the best of all the 12AX7’s I had ever tried in it. The guy I sold it to, was so nice I sent them along with a few other NOS brands. I am now regretting it. I’ve had my present Alpha for a month and I am really missing them. I have an order in for some 1990 NOS Golden Dragon’s and I’ll let you know how they sound.
Hi again all,
I'd like to conclude this post, and end it with some very nice news, that all is well in CAL Alpha-Land!

As was later suspected, and through the help of all you kind helpful folks here, and especially Tom (Zinfan) the CAL Alpha has been known to be a bit more sensitive to Tube Choices than it's less expensive sister, the Sigma-Sigma II DAC.

Yesterday, I recieved 4 new 12AX7A-c9 Shuguang Tubes from an Ebay seller (for $24.00 plus shipping) and after installing them this afternoon, and doing a test listen, my CAL Alpha has never sounded so durn good!!!!

I won't doubt other's findings about Vintage NOS Tubes Like Sylvania 3-Mica BlackPlates, etc being grand, but I honestly cannot see substantial gains being made, as this Unit of mine seems to lack absolutely nothing at the moment. I'm sure after a bit of breakin, they'll even sound a bit better!

I am surprised at the nice build quality of these Chinese Tubes, posessing 3-Mica Spacers, and BlackPlates to boot (Appear to be a round-halo getter)

I hope this post to this thread helps other CAL Alpha owners to find a nice Tube, in which one won't have to run the gamut of NOS Vintage Tubes, and spend a veritable week's paycheck to get enjoyment. I've found these Tubes to offer quiet operation, solid authorative Bass, smooth, crystal clear mids, and superb, soild highs, without being Tizzy, or harsh, andgreat dynamics.

I'm very glad that A-Gon is here for us all, and wish to thank all again who've responded to me here, and in the past. Mark D.
hi markd51:

i have a cal alpha and have tried a variety of tubes and have found the dac insensitive to tube changes.

just for the record, have you found any tube which rolls off the treble and shifts the balance to the lower mid range ?

the chinese tubes you mention, i assume are current production easy to find.

i am surprised you like the tubes. i have yet to hear anyone speak well of chinese 12ax7 tubes.
Mr T, There are a number of folks on the AA tube forum that have posted positive comments about these tubes. Haven't heard them myself, and I don't know what about them differentiates them from the croud. Nor have I heard anyone describe them as rugged, but the good new is they are cheap.