Ceriatone Forum

Anybody changes the stock tubes?

I tried the EI NOS tubes. The clean ch sounds much better with Ei tubes but I like the OD ch more with Tung-Sol tubes. Ei tubes are much clearer (more hi end and better bass definition), I could say more HiFi sounding but you lose that smoth tone which you get with Tung-Sol tubes.
I also tried Ei in V1 and Tung-Sol in V2 and I still prefer OD tone with Tung-Sol in both positions.

 ;)

Well I have an interesting story... just today I had an opportunity to try a lot of tubes. Unfortunately I didn't have my OTS with me, so we used plexi superlead amp.

The guy was changing V1 tubes and I was playing... I think we went through 8,9 different tubes... Philips, Simens, Ei, JJ, Tung-Sol, RCA, Mullard, Sovtek maybe some more.
I don't know how but I picked the most expensive NOS tube as the best one. It was the RCA.
... but just for the record, I'm not spending more that 100€ on a tube and I don't care how good does it sound. I did buy a Ei tube, 'cause it sounds so clean... and I thought, I better get one before prices on those go to high too.

 ;)

Fortunately I have a very large supply of NOS and ANOS tubes, so I did not order my amp with tubes. Proper tube selection can make a big difference in the tone and response of most amps. V1 is going to be the most important in the Overtone as it affects both clean and OD tones. Spend time going through various tubes, checking for tone and microphonics. It's probably the most important tube in the amp. Bugle Boys, RCA's, Mullard, and Telefunkens work well here, but long plates may be somewhat microphonic unless you sort them. I've found EI's to sound a bit jangly, and like them better in AC30's than D-type amps.

V2 will be your OD tube, so also go through the same process there, focusing on the range of OD drive and microphonics at volume. Make sure you have your trimmer set properly as that makes a huge difference in the character of the OD. Too high will be harsh. You may want to re-select tubes here if you make a big change in the trimmer.

After that, I often will like a GE 5751 for the phase inverter, but try different tubes because in that position relative balance between halves can make a difference. They don't have to be matched, but they will sound different if they are mismatched from one side to the other.

For the power tubes, RCA 6L6's sound really good in the Overtone, but may not be worth it if you only play lower volume. I've had good results with Tungsol 5881's also. Good NOS tubes will generally sound better and last much longer than new production tubes.

Nuff said

I still prefer JJ ECC83S in all three positions, tried EH ECC83, but the draw less current and consequently sounds brighter and thinner. I found this to be a general rule with the tubes I have i my old drawer, counting (OLD! not NOS) Mullards, Brimer, Siemens and GE7025.

Dumble seeker, when you try out different preamp tubes, try to measure the plate voltages (pin 1 to ground / pin6 to ground) and see if find the same connection betweeen brighter tubes, showing higher plate voltages. Could be interesting with a little field study.  ;)

What about different power tubes? I heard somewhere Carlton uses Sovtek 5881 tubes in his Dumbles for more dirt and crunch?

+1

I agree, plate voltages change with pre-amp tube, JJ's generally draw more current,  making it darker. Every other tube I tried draw less current ending up with a higher plate voltage and is therefore brighter.