'57 Guild Model 66-J........

[SFIV1967]

What year is the amp in your picture? It has a full back panel, where mine has a top panel, and a bottom one. Also, that one has a Tremolo selector, where mine does not.
And, I'm seeing screws on the strap hold-downs. I was thinking that I would have to drill out the rivets on mine, and the picture confirms that those have been removed. Good picture.

Jack: I had the link posted behind the name Zizala above (click on it).
Probably that was also a replaced handle already and maybe somebody also changed the rivets to screws.
Here is another schematics: http://4.bp.blogspot.com/-9cz7E1wCS6c/UQE3YVEo0XI/AAAAAAAAFyY/sj0kusdCWFE/s1600/gamp6.JPG

And another one: http://img.photobucket.com/albums/v236/Tinknocker/amps/100_3579.jpg

But all not with 7 tubes...

EDIT: I now read the complete Hoffman Amps forum discussion, now I see what you have and how the schematics looks. Interesting.

Ralf

 

[Default]

Zizala's amp is a Model 66, but not a 66"J". The Zizala amp has 50l6 power tubes and runs from wall voltage. Different amp entirely.
Also, While Sanders may have been trying for vibrato, he may have been just designing by trial and error. That's what I think when I look at Jack's amp and definitely when I look at the wierd Masteramp that I have.

Btw, what's the date code on that Jensen? I have the feeling that your amp and mine were built almost the same time.

 

[zizala]

Thought I'd move comments on the '57 Guild Sonola to the Guild amps section but was absent of mind and succeeded only in erasing my text here

Anyway......its over there.....I'll try again later

D

 

[Default]

Just another note on the handle. Rivets would not be used on a wooden amp case. You would either screw into the cabinet itself or you would use machine screws into nuts or t-nuts. Maybe they used rivets on the metal cabinet amps in the thirties and forties, but I'm willing to bet a leather handle is whar it came with.

 

[59Panhead]

Btw, what's the date code on that Jensen? I have the feeling that your amp and mine were built almost the same time.

If you mean my amp, the speaker code is 220626, though the pot codes make it at least a '57.

Jack

 

[59Panhead]

Just another note on the handle. Rivets would not be used on a wooden amp case. You would either screw into the cabinet itself or you would use machine screws into nuts or t-nuts. Maybe they used rivets on the metal cabinet amps in the thirties and forties, but I'm willing to bet a leather handle is whar it came with.

I used a mirror to take a quick look at my 'rivets'. I was fairly sure that I knew how it was attached, but I have confirmed it. It's basically attached in the same manner as some of my old Gibson amps. For lack of a better description, I'll call it a long rivet with a split end. After it's pressed through the wooden cabinet, a washer is slipped over the split end, and the ends are folded/swaged outward and flat against the washer. My only recourse, unless I can find more of the same, it to drill the split ends and use machine screws with nuts. I'll probably go this route, though I have been known to chase this rabbit until I find the correct 'rivet' replacement.

Again, there may be a different proper name for this attachment. I'm hoping someone will clue me in. I'll post what I find. Thanks for all help.

Jack

 

[SFIV1967]

Again, there may be a different proper name for this attachment. I'm hoping someone will clue me in.

Simply called "Split Rivets"! It's the same how all the brass parts and handles on wooden guitar cases are fixed with. They are available from suitcase makers / repair shops in all kind of sizes and materials. They don't require a washer if installed correctly! See second picture. You spread the legs of the rivet with a small screwdriver, curl them around with needle-nose pliers, then gently pound the curled legs into the wood while holding another hammer head against the head of the rivet.

Ralf

 

[mavuser]

Hi Jack Fender sells the reissue leather handle you and I both need.

I THINK the handle is a standard size...and one came stock my Fender Blues Jr Tweed, which is the same size as my 66-J. I can measure the space between the mounting brackets later when I get home. Even a larger Fender/tweed whatever amp though, I think would use the same size leather handle. basically any amp with those exact mounting brackets pictured with the strap...

FWIW Fender has all the variations of reissue vintage amp handles. Those guys don't play games. several different versions of leather, vinyl and whatever else. All the brackets...I wouldnt even call them "reissues" more like just replacement parts, as they are in-kind.

Jack if you want you can send me your PDF at esinger39@hotmail.com. I will see what I can do with it and try to post it here for you (probably after Jan 1). photos need to be hosted at a different site (like Imageshack) and then posted here with using the photo icon in the toolbar. Not sure about PDFs though. send it over if you wish, ill try to play with it.

 

[59Panhead]

Thanks, Ralf.

My rivets are steel, but they shouldn't be hard to find, now that I know what they look like as new.

Jack

 

[59Panhead]

Hi Jack Fender sells the reissue leather handle you and I both need.

I THINK the handle is a standard size...and one came stock my Fender Blues Jr Tweed, which is the same size as my 66-J. I can measure the space between the mounting brackets later when I get home. Even a larger Fender/tweed whatever amp though, I think would use the same size leather handle. basically any amp with those exact mounting brackets pictured with the strap...

FWIW Fender has all the variations of reissue vintage amp handles. Those guys don't play games. several different versions of leather, vinyl and whatever else. All the brackets...I wouldnt even call them "reissues" more like just replacement parts, as they are in-kind.

Jack if you want you can send me your PDF at esinger39@hotmail.com. I will see what I can do with it and try to post it here for you (probably after Jan 1). photos need to be hosted at a different site (like Imageshack) and then posted here with using the photo icon in the toolbar. Not sure about PDFs though. send it over if you wish, ill try to play with it.

My original brackets measure 7-3/8" between centers. If you are able to link me to something that would be exact, or closely emulate what I should have had, I will pick one up. I'll head over to McMaster-Carr to see what they have in the way of split rivets, though I'll have to wait until I get one of mine out to see what diameter that I need.

Though now, that I see your picture, and the manner that they attach, I may go that route. I like that setup better.

And, you have an email with a copy of my schematic. I sure hope that it will do someone else good. The detail is can be time consuming, but I depend heavily on schematics to troubleshoot. And, drawing one from scratch clues me in to any oddities that are out of the convention of other amp designs. Especially, if they have been modded in any way. Those stand out. In my case, it has all the appearances of being original to the amp. The little speakers may have been an add-on. If so, that may explain the failure of the OT, as the combined set is 8 ohms paralleled with the 8 ohm Jensen. When I put a new one in, it will be multi-tap, and I'll use the 4 ohm winding for my configuration, as I have no plans to remove the little speakers. If I do make a change in the speaker impedance, I can pop the back panel and re-solder the correct tap to the jacks. I'll have them marked for any future changes, should they arise.

Jack

 

[Default]

Aren't those 5" speakers going to blow pretty easily if you parallel them with the main speaker?

 

[59Panhead]

I just put a ruler on the speakers. The cones are 3", with 3-3/4" between screw holes.

To answer your question, they probably will in a performing environment. In my home, or possibly in a friend's studio, they will do just fine. The amp will never be played loud in either of these places. My friend Wade Baynham has Second Story Studios over in Durham, NC, and is presently using some of my tube resurrections. He mic's all his amps, so they are played mostly clean, unless they are small, like the little Champion 600. I'm now wondering if this one was used for recording, now that you bring up the possibility of blowing the small ones. It would have been used at safe levels, if so.

I'm also now thinking that as an add-on, the effect of the change to the primary impedance was not taken into account. If this is true, the amp could have been out of commission for a very long time. Explaining the cooked resistor on the front end of the PS de-coupling circuit. The old schematic shows a 560R, where I now measure something double that value on mine.

Jack

 

[Default]

I always thought that tweeters were isolated from the ot impedance load by capacitors. Guild did use tweeters on some of it's amps. Wally Marx did an article on Guild amps for Premier Guitar(?) where he had a gutshot of some monsterous stereo 50L6 Guild amp that had tweeters. I'm not sure what Han's book says about that, I'm at work and the phone doesn't search well.
Otoh, I seem to be wrong about wverything lately.

 

[Default]

I always thought that tweeters were isolated from the ot impedance load by capacitors. Guild did use tweeters on some of it's amps. Wally Marx did an article on Guild amps for Premier Guitar(?) where he had a gutshot of some monsterous stereo 50L6 Guild amp that had tweeters. I'm not sure what Han's book says about that, I'm at work and the phone doesn't search well.
Otoh, I seem to be wrong about wverything lately.
http://digital.premierguitar.com/pr...ticleId=11357&mobileWeb=true&lm=1372697267000

 

[59Panhead]

Not wrong at all. Too many inconsistencies in builds of the same model. However, I believe that you are right about proper isolation by means of caps. My B-12-XY has a tweeter/horn isolated with a 50uf-50v capacitor. This thread is convincing me that I have add-on speakers, though I plan to correctly configure the OT secondary in order to retain them.

Jack

 

[mavuser]

The Fender Blues Jr Tweed and Guild 66-J are nearly identical dimensionally, but the spacing on those mounting brackets for the handle is bigger on the vintage Guild (therefore the handle is/was longer on the Guild). I will measure the Fender Blues Deluxe next time I'm at my buddy's GC here locally. Maybe that one is a perfect match. If not, the smaller leather handle can be made to work at least aesthetically, but likely at the sacrifice of its function/integrity. The center of those brackets measure 7.5 inches to each other on my 66-J, and 5.75 inches on the Fender Blues Jr. Tweed. Again they look the same and the handle can be made to fit on the Guild, it would look good but I wouldn't carry it that way. Will check the Blues Deluxe soon

 

[Bill Ashton]

Jack, emailed you both my (original) 66-J schematic as well as a 99-J schematic that I somehow think you will eventually need...LOL!

Couple points: My regular tech (before Default) gave me back a marked up schematic that he said was more accurate as to what was
really in my amp, so don't take the one I sent you as gospel. I still have the black leather handle that came with my 66-J, took it off
years ago as I just did not trust it; that said, the one on my 99-J ('61) seems to have weathered the years just fine. I think its the difference between a closet jazz amp and one that was doing the bar circuit (I bought it out of the back of a van in 1968...)



I would suggest that the speaker EIA code is not a reliable method of dating a Guild amp. Mine had (has) a P12R from 1959, original solder joints, cable passed through the jack on the chassis...just as my 99-J was. Yet with a dental mirror the pot codes make it 1963. Cannot remember or remember if I remembered to look at the tranny or large cap codes. But if it was like Steve said and they just went down the street to You-Do-It-Electronics and bought parts, then it kind of makes sense.

At least they didn't go to Radio Schack!

Another thought...if you come up with a source for proper black rubber feet, figure me in for 12!

 

[59Panhead]

I too trust the potentiometer codes over speakers. Speakers are way too easy to get at, to swap out. Pots ain't. Plus, all my pots say '57.

Got the schematics saved. Your 66-J is the clearest of any that I've found. Thanks a bunch.

As to the 99-J, and needing a copy sometime. You've got to stop reading my mind. There's a whole lot of stuff going on up there, and you can get lost. You might run into some of my Fish Carburetors, and never make it back.

If you ever get around to scanning the marked-up schematic, remember my need for all things schematic. Thanks, again.

Jack

 

[59Panhead]

Ok. It looks like I've located a suitable OT for my amp:

http://store.triodestore.com/tf65wscta48opaper.html

It has the same 3-1/8" footprint as mine, and a multi-tap secondary. It has primary windings for the screen grids, though I won't need them. Nice to know, for future projects.

Here's the drawing:

http://site.triodestore.com/TF110_Paper_BobbinWIRINGDIAGRAM.jpg

I think I'll order one tomorrow.

Jack

 

[mavuser]

Nice!!! Awesome u have had them for so long too