Grateful Dead Music Forum

So, long story short, after putting some amazing (and amazingly heavy) JBL e120s into my '65 Fender Twin "Reissue" it was time to upgrade the tubes after my power tubes were dying and I started blowing fuses. I'm pretty damned convinced now that if you're looking for that early 70s Merl/Jerry Keystone-era tone you can get damned close if not exact with what I just put together with my amp guy here in Nashville.

Fender '65 Reissue Twin Reverb with JBL e120s

4 matched Groove Tube 6L6GEs with a power rating of 5

Then in the following slots for pre-amp tubes we went with:
V6 12AT7 JJ Phase inverter
V5 RCA 12AX7 Fender-branded short plate tube
V4 Groove Tube 7025
V3 Tungsol USA-made 12AU7A for the reverb
V2 Phillips JAN 12AT7WC
V1 RCA12AXY7 - 7025

For my ears, its very Keystonesque, and just the right combo of tubes, and speakers, without breaking the bank or worrying about carrying around a vintage Twin.

Your mileage may vary.

Try swapping V1 with V2. Also, V3 should sound better with a At7. What you have will work, but I think you could have better results. The next big mod you can make is changing the tone stack caps to .022's.

Thanks. I play through channel two primarily. We actually spent about three hours last night auditioning tubes in different V spots with my pedal board and guitar to dial this in for me. My guy had an amazing arsenal of tubes to try.

Like I said, your mileage may vary.

mikelawson wrote:Thanks. I play through channel two primarily. We actually spent about three hours last night auditioning tubes in different V spots with my pedal board and guitar to dial this in for me. My guy had an amazing arsenal of tubes to try.

Like I said, your mileage may vary.

Ditto on the swap if you use Ch 2 and not 1, but Philips JAN is great too and your ears may tell you to switch it back. Either way, you are only using one of V1 or V2 at a time (unless jumpering the channels)

Two E120's....must be incredibly heavy!

pula58 wrote:Two E120's....must be incredibly heavy!

The things we do for tone... I call it "The Hernia Maker." In its new custom road case, its ridiculously heavy, but its on 4" nylon wheels, so that helps a bit.

tigerstrat wrote:

mikelawson wrote:Thanks. I play through channel two primarily. We actually spent about three hours last night auditioning tubes in different V spots with my pedal board and guitar to dial this in for me. My guy had an amazing arsenal of tubes to try.

Like I said, your mileage may vary.

Ditto on the swap if you use Ch 2 and not 1, but Philips JAN is great too and your ears may tell you to switch it back. Either way, you are only using one of V1 or V2 at a time (unless jumpering the channels)

Yeah, I should explain a little more.... I actually am using both quite often, because I will plug my guitar rig into channel two, and my synth into channel one and blend it all. It actually works quite well in smaller situations where I'm not running stereo out on the synth to the house, or to separate amp. So when we were doing all the pre-amp tube testing, the synth in channel one was part of the mix. Thanks for the tips, though.

My only real disagreement here would be the speaker choice. The JBL E's didn't exist back then, and it would have been K120's or D120F's. Alnico vs Ceramic, it's a real thing, especially when power tubes are distorting and driving them. The alnico JBL's sing quite a bit better in a Twin compared to the ceramic E's that don't even blink, don't stress or get "musical" at all in a Twin. Alnico JBL's are a significant part of that formula, in my opinion.

And if you really wanna go nuts, the vital signal path, especially plate resistors, would be Allen Bradley carbon comp types. That's what Alembic/Wickersham had in all those Twins of theirs back then.


Brad

Not to take this thread off course, but any time I hear that the alnico JBLs are just that much better than the ceramics I get real bummed out. I've tried many times to get them on eBay, and they always get screwed up in shipping. I've since given up trying to buy them as I don't want to remove more from circulation. I wish somebody would make a clone!

And if you really wanna go nuts, the vital signal path, especially plate resistors, would be Allen Bradley carbon comp types. That's what Alembic/Wickersham had in all those Twins of theirs back then.

Hey Brad,

Thanks for your insight on this. Layman's terms ...well almost, but that's great advice and something I could take to my local amp tech to get an upgrade.

I'll second you on the K/D120's. They definitely have a crunchier, sweeter sound. I've got two cabs, a 1x12 E120 and a 2x12 D120 and I can run them both from my Vibrolux. I think I'll try to do a real simple comparison.

My Blues Deluxe is a bit noisy these days. I think I need to re-tube it. It's a sweet amp, as I've got a D120 in it. On some levels I like it more than my Vibrolux. It breaks up easier. Can anyone recommend the "Garcia" correct tubes for this amp....and are their any simple mods I can have done to make a sweet amp even sweeter.

It's my only JBL combo amp these days so I use it a lot for rehearsals and jams.

Peace,

James

I guess you'd have to hear it in person.

SarnoMusicSolutions wrote:My only real disagreement here would be the speaker choice. The JBL E's didn't exist back then, and it would have been K120's or D120F's. Alnico vs Ceramic, it's a real thing, especially when power tubes are distorting and driving them. The alnico JBL's sing quite a bit better in a Twin compared to the ceramic E's that don't even blink, don't stress or get "musical" at all in a Twin. Alnico JBL's are a significant part of that formula, in my opinion.

And if you really wanna go nuts, the vital signal path, especially plate resistors, would be Allen Bradley carbon comp types. That's what Alembic/Wickersham had in all those Twins of theirs back then.


Brad