I’m a late bloomer to this amazing world, the world of understanding amps and electronics as it relates to sound. For 25 years I played a 1972 Twin and never thought twice about it. Now I’m questing for the ultimate surf tone. I just got a ‘64 Showman w/ 15” tone ring re-coned JBL D130F. Got surfy bears. Got jaguars and a jazzmaster.

It’s time for tubes. Which I know almost nothing about, except what I’ve been reading. 6L6 and 12AX7.

Everyone knows vintage, high-testing NOS tubes are best. After reading everyone’s opinions, I’m not going to bother with new tubes. Not while NOS ones are still attainable. I’m looking to purchase from Brent.

But which are the SURFIEST NOS tubes? I’m looking to fit three Twins with the best tubes for under, say, $1000. The Showman has GE tubes that are probably great so for now I’m just messing with the Twins. I’m starting with the power tubes and the clean channel preamp, V1.

RCA 6L6GC blackplates? Seems like these are the most affordable of the “A list” 6L6s. The other NOS 6L6s didn’t sound as exciting. Any other awesome 6L6s that aren’t $400 - $1000 a pop?

I’m looking at these three 12AX7 types. Brent’s got some “Butt Uglies” of these.

• Sylvania 5751, greyplate TRIPLE MICA Premium 12AX7, military type

• RCA 12AX7 BLACKPLATE tubes

• RCA 5751 Premium industrial grade 12AX7, 2 mica

I was gonna get one of each and try one in each Twin.

I did read about swapping the V1 12AX7 for a 5751 to increase headroom? One of the Twins seems to need that. Also the 12AT7 and 12AY7 would do this too? I think I’m confused.

Also pulling out the V2 tube to give the clean channel more volume.

Those last two came from here:
http://music.codydeschenes.com/?p=669

And biasing. Every time I switch a tube, I’m going to have to wait weeks for the one tube amp guy in town to rebias. That suuuuucks! Since I’m paying “vintage” prices I don’t want to risk over cooking. I’m scared to plug them in at all until they’re fed matching voltage. I looked up some YT videos of biasing Twins and it was scary. For someone like me who has hardly any free time at all, there’s no way. I can purchase a meter but I don’t have a proper bench, and more importantly I don’t have the knowledge of how to do it safely! All the Twins are old so the bias adjustment is inside. I have never opened up an amp...

Daniel Deathtide

You’re crazy!

Daniel Deathtide

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Ben wrote:

I agree with you on one thing...you know nothing about tubes. Not that aren't differences between them and lots of interesting reading to be done. But, stick a set of new JJ's in there and unless you have ears like Eric Johnson you'll probably never know difference (certainly with the power tubes). Spending $1000 on NOS tubes is crazy!!!

Try this test: Listen to your 5 favorite surf cd's and tell us what kind of tubes they're using.

^ this dude gets it
well said

I apologize...I didn't mean to be patronizing. I was being sarcastic and exaggerating to emphasize the point. If you can get ahold of a Weber Bias Rite or something similar I would be happy to help you learn how to use it safely

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kick_the_reverb wrote:

Taking the risk of hurting your tech's cash flow...but in case you haven't taken the hint above. You only need to re-bias if you are changing power tubes. Feel free to play around with a selection of preamp tubes.
When I had one amp, it was all NOS tubes. Now that the amps need to sound similar and loud, I use JJ Tesla 6L6GC.
The style of circuit matters as well. What sounded good with my Blackfaced Twin Reverb (Philips 7581A), sounded like a bass amp on a Surfer. Philips/Sylvania STR415 and STR387, although similar in construction, sound better to me in a Brownface circuit.
Good luck.
Ran

That's what I was referring to in my post. Preamp tube swaps don't necessitate a bias adjustment. Power amp tube swaps do, but there is more to be gained (get it? haha) by fiddling with preamp tubes.

https://www.amazon.com/Tube-Amp-Book-Deluxe-Revised/dp/0879307676
This book is a little pricey but there's a ton of info about tube amps and tubes for those amps ,the why and where of it all . And info about current production tubes for use in vintage amps . The prices on NOS tubes from the 60s are outta my league so I have my amp tech use whatever he thinks will sound best at a reasonable price . Im pretty sure I have JJs in most of my amps by now . My Park head has a complete set of Groove Tubes . I tell them what sound I want and let the experts recommend something , so far so good .
Maybe you can make an appointment with the amp guy close to you , play the amp until then , look at online tube suppliers and pick some to bring with you . Rebiasing shouldnt take very long unless you have other issues . Play with the preamp tubes all you want , no rebiasing needed . and dont forget the phase inverter tube !

kick_the_reverb wrote:

When I had one amp, it was all NOS tubes. Now that the amps need to sound similar and loud, I use JJ Tesla 6L6GC.
The style of circuit matters as well. What sounded good with my Blackfaced Twin Reverb (Philips 7581A), sounded like a bass amp on a Surfer. Philips/Sylvania STR415 and STR387, although similar in construction, sound better to me in a Brownface circuit.
Good luck.
Ran

Thanks a lot! THIS is exactly the kind of info I’m seeking. I might have to look up a Philips for the Showman. This also shows that changing tubes can change the sound. I’m not sure why people were saying that tubes don’t matter. Anyone else have this kind of valuable experiences to share?

I currently have JJ 6L6s and I do not like the sound of that amp. Other Twins have Groove Tubes and they sound way better. I don’t have the knowledge (and time) to check and compare every cap and resistor, but they’re all 1970 - 1974 amps. The Showman is my first blackface and I don’t know what it’ll sound like with modern tubes. (I also don’t know how healthy the GE tubes are!)

I am changing power tubes so biasing is necessary, but I am eagerly awaiting trying out some Preamp tubes at home!

That is a GREAT thought about making an appointment! It’d have to be the weekend because of my work but maybe he can be available. If so I’ll bring all four amps!

Daniel Deathtide