Gretsch Electromatic 5222

[tunghaichuan]

Found this Gretsch Eletromatic 5222 amp pr0n on the Gretsch pages:

http://gretschpages.com/forum/gretsch-amps/inside-the-g5222/10411/page1/

I believe the circuit is the same as the Fender Champion 600, with different cosmetics. I like the styling of the Gretsch better.

It may be my next purchase.

the chassis looks ultra simple: just a bend in a sheet of metal with the bent part serving as a face plate. It probably wouldn't be too hard to fabricate this type chassis.

I think it would be cool to make another chassis and wire in an eyelet board circuit.

tung

 

[markb]

It's the same amp. Fender own the Gretsch brand so the choice is tweed or two tone vinyl jacket.

 

[tot_Ou_tard]

Way cool tung! Let me know if you are interested in making two such chassis/eyelet boards. I might be willing to buy one from you.

BTW, I did order a yard of oxblood grill cloth from Antique Electronic Supply.

You can have the excess, if you'd like.

 

[tunghaichuan]

tot,

I'm pretty close to pulling the trigger on one.

I'm going to look into having a machine shop make me a chassis. That chassis is just a bend in a single sheet of metal.

There are a few circuit possibilities: 5F1 Champ, 5F2-A Princeton, a Valve Junior or GA5 circuit.

Another possibility is the 5C1 Champ. It doesn't get distorted very much even when the volume control is dimed, but it has a very pretty clean sound. It is an awesome clean blues amp. I built a version witha 6AU6 and a 6AQ5 that killed.

tung

Way cool tung! Let me know if you are interested in making two such chassis/eyelet boards. I might be willing to buy one from you.

BTW, I did order a yard of oxblood grill cloth from Antique Electronic Supply.

You can have the excess, if you'd like.

 

[tot_Ou_tard]

tot,

I'm pretty close to pulling the trigger on one.

I'm going to look into having a machine shop make me a chassis. That chassis is just a bend in a single sheet of metal.

There are a few circuit possibilities: 5F1 Champ, 5F2-A Princeton, a Valve Junior or GA5 circuit.

Another possibility is the 5C1 Champ. It doesn't get distorted very much even when the volume control is dimed, but it has a very pretty clean sound. It is an awesome clean blues amp. I built a version witha 6AU6 and a 6AQ5 that killed.

tung

The 5F2-A Princeton & the 5C1 Champ seem very interesting.

What are the differences?

5F2-A demo here:

 

[tunghaichuan]

The 5F2-A Princeton & the 5C1 Champ seem very interesting.

What are the differences?

5F2-A demo here:

I'll have to watch that demo when I get home tonight, my employer doesn't allow me to watch youtube videos at work. (They also frown on posting to message boards, but I digress. )

The 5C1 was an early version of the Champ. It looks a lot like your Champion 600. In fact I think the styling was taken from an earlier version of this circuit called the Champion 600. The 5C1 has a grid leak bias 6SJ7 pentode for a preamp, a single volume control, a 6V6 output tube, and a 5Y3 rectifier tube. I believe it had a 6" speaker like the new 600.

I built a version of this amp using a 6AU6 preamp pentode and a 6AQ5A power tube pentode. The 6AQ5A pentode is roughly equivalent to the 6V6, but with lower ratings. It is a very chimey amp and has a very pretty clean sound. It has almost no breakup even when dimed. It might be due to the 6AQ5, though. These tubes are smaller than 6V6s and brighter. They sound like a cross between a 6V6 and an EL84. I do plan to build a copy of the 5C1 using a 6SJ7, 6V6, and 5Y3. Maybe yet another tutorial?

Here is a picture of a real 5C1's wiring:

As you can see it is true point to point, unlike the 5F1 & 5F2-A which are eyelet board construction.

The 5F1 Champ and 5F2-A tweed Princeton are both very gainy amps. They have a 12AX7 in the preamp which provides much more gain than a single 6SJ7 or 6AU6. The preamp stays fairly clean, however. Distortion in these amps is generated by the preamp driving the 6V6 into power amp distortion.

I think a cool project would be to build the 5C1 into a replacement chassis that one could swap out with the stock chassis. It would be a cool little stealth amp.

tung

 

[tot_Ou_tard]

The 5C1 was an early version of the Champ. It looks a lot like your Champion 600. In fact I think the styling was taken from an earlier version of this circuit called the Champion 600. The 5C1 has a grid leak bias 6SJ7 pentode for a preamp, a single volume control, a 6V6 output tube, and a 5Y3 rectifier tube. I believe it had a 6" speaker like the new 600.

I built a version of this amp using a 6AU6 preamp pentode and a 6AQ5A power tube pentode. The 6AQ5A pentode is roughly equivalent to the 6V6, but with lower ratings. It is a very chimey amp and has a very pretty clean sound. It has almost no breakup even when dimed. It might be due to the 6AQ5, though. These tubes are smaller than 6V6s and brighter. They sound like a cross between a 6V6 and an EL84. I do plan to build a copy of the 5C1 using a 6SJ7, 6V6, and 5Y3. Maybe yet another tutorial?

Here is a picture of a real 5C1's wiring:

As you can see it is true point to point, unlike the 5F1 & 5F2-A which are eyelet board construction.

The 5F1 Champ and 5F2-A tweed Princeton are both very gainy amps. They have a 12AX7 in the preamp which provides much more gain than a single 6SJ7 or 6AU6. The preamp stays fairly clean, however. Distortion in these amps is generated by the preamp driving the 6V6 into power amp distortion.

I think a cool project would be to build the 5C1 into a replacement chassis that one could swap out with the stock chassis. It would be a cool little stealth amp.

tung

I have a 5751 in mine. Nice cleans-breakup on the low input it can get more distorted on the hi input.

A swapable chassis is a sweet idea.

 

[tunghaichuan]

I have a 5751 in mine. Nice cleans-breakup on the low input it can get more distorted on the hi input.

I have a few NOS 5751s that I need to try out in my various amps. I tried one the other day in my modded Valve Junior head, and I still got plenty of gain out of it when I cranked the volume all the way up. The amp didn't mush out and over-compress like it does with a 12AX7, though. Very cool.

Another tube I need to try is the 12AY7. I only have one or two of those and maybe a 6072 which is the low-noise industrial version. They are slightly lower gain than the 5751.

A swapable chassis is a sweet idea.

Those chassis would probably be dead easy for a machine shop to make. The hardest part wold be cutting out the radius on the top corners of the bent-up face plate. I know Harbor Freight sometimes has a light-duty sheet metal brake on sale. It would probably do an adequate job.

The problem with contracting work like this out to a sheet metal shop is that they usually have very high set up fees. And if you order 2 or 3 chassis, the per unit cost is high. They start giving you a break at 20-50 units.

tung

 

[tunghaichuan]

Here's a pic of the 5C1 clone I did:

http://www.diycustomamps.com/images/5c1_clone.jpg

I departed from the original design by using the aforementioned tubes and I put in an eyelet board instead of wiring it point to point. Also, the rectifiers are SS devices; the original used a 5Y3 tube recto.

It might be be fairly easy to shoehorn one of these (or the tweed champ/princeton) into the Champ 600/Electromatic 52222 chassis.

I have a line on a used, mint-condition Champ 600. I found it on line last night and it is at a local guitar shop. I'm going to check it out Monday.

tung