Early 60's Fender Concert, Brown

[Robert****]

Keep it!

[Spudman***]

I sent Joe Bonamassa a PM to let him know about it.

[sunvalleylaw]

Keep it!

Ha Ha! I did! (Hi, Robert, by the way! Hope you are well! We are ok down here.).

I have kept it, and am finally fixing up a couple things. I had a pre-amp tube go bad and have found a suitable replacement and pulled the trigger there. I could have gone re-issue or cheap, but got two NOS (trying one Mullard 7025 and one RCA to see which I like, then will return the one I don't and replace it with another of the one I like) to try out in the first stages section of each channel, which makes more of a difference, and will move one of the tubes (old US Made 7025, looking like GE made)into the slot of the bad microphonic one.

I am starting to play again, and since we are playing home, and maybe outside, figured I might start using this one for outdoor distant playing in my driveway or yard, instead of the C-30, seeing as I have owned it all these years.

Even with a cheap Groove Tube I stole from my C-30 thrown in, the amp sounds great again, and now will handle more dirt and/or fuzz whereas before it was making bad sounds if I played through those pedals, or bumped it with my tele.

Seems a lot better now. So, will swap out those tubes, and give the GT back to the C-30, and off and running!

[sunvalleylaw]

The tubes are listed as 5881 5881 7025 7025 12AX7 12AX7 7025 7025 in a little chart inside the cabinet.


This is an explanation from a guy that helped me understand what was going on.

Back in ye olden days, 7025 was the designation for a low-noise, low-hum 12AX7 for hi-fi purposes. This only applies to NOS tubes, modern tube makers mix and match all the old tube designations the same way they use old company names...it's just whatever the marketing department decide to call the tube.

In the Concert, the two 12AX7 are 3/5 of the tremolo circuit, they don't see the guitar signal and their fidelity doesn't matter, so Leo could use whatever 12AX7 he wanted there. Counting from the input side of the amp...
V1 - First two stages of Normal channel
V2 - First two stages of the Vibrato channel
V3 - Drives the LFO for the harmonic tremolo circuit
V4 - (only 1/2 the tube used) - LFO inverter for the harmonic tremolo circuit
V5 - Low- and high-pass amplification stage for the harmonic tremolo circuit
V6 - Long tail phase inverter
If you want modern tubes, the popular modern choices are the Tung Sol and Mullard 12AX7, both made in Russia at the same factory. You can buy them just about anywhere, find a dealer who has reputation for good customer service.

NOS? These are getting even more expensive and less trust worthy as stocks thin down (more and more I run into have some sort of hiss or static). But KCA NOS Tubes, Tube World, and Brent Jessee Recording or probably the best resources.

So yeah, will replace the tubes in v1 and v2 with the NOS I am getting, then move one of those GE made 7025 tubes into V3 where the microphonic old Tung-sol 12AX7 was and keep one 7025 in reserve.

Will also start looking for some NOS 5881's or 6L6WGB's (same thing, but toughened up for military use) to hold in reserve should the ones I have go out.

[marnold***]

I think sometimes the best sales are the ones you don't make.

[sunvalleylaw]

So I received and put in some new tubes. First, I found some good used vintage 5881’s to have as back ups to the 6L6WGB tubes that came with the amp. But I am enjoying them in it and think I am getting a break up at a little lower volume. And they may seem a little warmer. A fun change.

Then, I received the NOS 7025’s I ordered, one Mullard, and one RCA. So far I really like the Mullard in the V1 position, the Normal channel of the amp, and the RCA in the Vibrato channel, V2. But I may want to exchange the RCA for the Mullard. I will swap back and forth and see what I think. I also got for cheap a 5751M which apparently is an tube SRV used. I will check that out too. And with the microphonic tube replaced permanently with a good 7025 I took out of V1 or V2 (and I have one leg over) the amp is different creature. My pedals all work better, and my fuzz pedals that didn’t seem to want to work sound awesome. A lot of fun to get to know the amp all over again! Glad I didn’t sell it!

[duhvoodooman***]

Yo, Steve!! Wondered if you ever came across this video by YouTube vintage amp maven "Uncle Doug"? This brownface Concert is the same year and version as yours:



And here's a second video (actually the first of two parts) featuring another 6G12-A Concert chassis that was pulled from the original combo cabinet and installed in a a silverface Bassman head cabinet:

[sunvalleylaw]

Yo, Steve!! Wondered if you ever came across this video by YouTube vintage amp maven "Uncle Doug"? This brownface Concert is the same year and version as yours:



And here's a second video (actually the first of two parts) featuring another 6G12-A Concert chassis that was pulled from the original combo cabinet and installed in a a silverface Bassman head cabinet:

Hey Bob! Thanks! I had not seen those. Will check them out. Been still playing that amp all this time, and loving it! Put some different tubes in, to replace a bad pre-amp tube that had gone microphonic, and also got a second set of good vintage 6L6WGB, 5881 equivalents and it sounds better than ever! I need to remind myself exactly what I got to try in the preamp section and report back. I got a few to play with and try out.

Best,

Steve

[duhvoodooman***]

Hey Bob! Thanks! I had not seen those. Will check them out. Been still playing that amp all this time, and loving it! Put some different tubes in, to replace a bad pre-amp tube that had gone microphonic, and also got a second set of good vintage 6L6WGB, 5881 equivalents and it sounds better than ever! I need to remind myself exactly what I got to try in the preamp section and report back. I got a few to play with and try out.

Steve, for you and any amp-aholics reading this thread: Uncle Doug has been a mainstay on YouTube since 2013, specializing in vintage amp demos and (especially) repairs/refurbs. His wheelhouse is amps from the late '40s through the '60s, with a heavy emphasis on old Fender units. His videos include a lot of "how to" amp work and repair information, with a healthy dose of electronic theory thrown in. He still manages to keep most of it very understandable, as long as you already have some familiarity with amp circuits and the basics of how they work. He's also a cat & dog lover as well as a vintage auto enthusiast, so you'll find bits of those topics thrown in to his videos, as well. Good sense of humor, too. Check out his YouTube channel here: https://www.youtube.com/user/Stratosaurus1

[Jipes***]

I had one from 1963 but I sold it years ago because the amp was far too clean for me even though the vibrato was lush and amazing. I now have a deluxe and I'm more happy with what I can get out of it for my style of playing DSC_0002.jpgDSC_0002.jpg