Revisiting Tube Recommendations for Cayin TA-30


My appologies if this has already been beaten to death! :)

I hope you all are up for this post! I'll owe you all big time!

I have a Cayin TA-30 (purchased in '03) with mods from Paul that included the sub out. It has been connected to B&W Nautilus 803's and a B&W ASW800. I have a Sony XA9000ES as my cd/sacd player.

I replaced them all once from Paul with EL34's, 12AU7's, and 12AX7's tubes, from EH. Simply put, the TA-30 just doesn't come close to sounding as good as the stock tubes did. It, to me, sounds so flat and not open like it used to. I bias the tubes about every 90 days to keep them running at their best.

So now come the questions.

1st. The broad question I have is I need to replace the tubes again, and I want to replace them all, but there are soooo many options and choices and I'm really not interested in "tube rolling", though I know I really should be. Where does one start? I'm overwhelmed!

2nd. The TA-30, I see, can accommodate my types of tubes. Is a KT88 "brighter" or better, or should I stay with EL34's like it's called for? Should optional tubes be used on the front end? Is the TA-30 "pushed" to much using these other tubes?

3rd. Since I have the TA-30 connected to the sub, should I focus only on mids and highs for tubes?

4th. Is there a source out there where I can get this information without bothering you all? I googled some variations, but just haven't had luck. Is it just me, or are all the tube reviews done on guitar amps, not home audio amps?

Well, wasn't that a mess??? :)

Thanks in advance to you all! I hope this thread can become a resource for all us TA-30 users!

Regards,
Bob
bstromberg1
Yeh rub it in guys unfortunately I have an older one that is me biasing. If anyone has input on the bias setting I would really appreciate the input. And if anyone is running them in the older unit please give me your thoughts. Thank you
Johnbonn,
Read my input from koiman 4 lines above. I put the bias values for the TA-30 and the stock EL-34 plus other tubes.
Lee
Thank you for getting back to me, so you are saying the 6L6 is the same as the 6n3ce setting? Have you tried the 6n3ce tubes? Thank you
This is from a print out I did a while back on biasing a TA-30 ...

"You will need a tiny screwdriver and the supplied digital voltmeter to set the 4 output tube bias adjustments. Switch the amplifier on. Let it warm up for at least a few minutes. Plug the digital voltmeter Black lead into the Black tip jack and the Red lead into one of the Red jacks. (turn meter on, set meter to the marked 2000mV range). MEASURE WITH THE VOLUME ALL THE WAY DOWN - NO MUSIC PLAYING. You should see a reading on the meter. Turn the corresponding 25-turn small adjustment screw for each red tip jack you are measuring till the meter reads 350 (mV). Now move the red probe to the next tip jack and adjust the next corresponding adjustment screw. Repeat all 4 adjustments a few times till all are reading 350 (mV) +/- 10%. Super easy! The bias should be checked immediately when new tubes are installed, then every 6 months there after. Unusual readings (after initial adjustment - very high or very low compared to the other tubes indicate a tube failure. Output tubes generally last around 3000 hours. So every 1-3 years you will need replacements. A computer matched quad is the best choice - but not absolutely necessary in this separate tube bias design."

*** NOTE FOR KT-88 TUBES *** Bias to 400

Bias into class A - using tubes 1 & 3 (pull 2 & 4 out) - set bias to 700(mV) (assuming 800(mV) for KT-88)
This will convert the PP amp to single ended

I hope Paul is doing ok - looks like the web site is down - has anyone heard anything?
Oh My ...

Paul Grzybek of tubeaudiodesign.com formerly Bizzy Bee Audio, passed away on or about March 20, 2012. Some might have known him for his restoration of Fisher 400/500/800 Receivers.

Paul was 48 years old when he passed away. A great loss to the 2 channnel and tube community. Too Young ...

Got this from Huhuru on another site ... I'll miss Paul too - he was a great guy with a passion for audio