I am searching for a schematic for a Yamaha G100 head, serial #2167. I can find plenty for combo amps, but not this one. Any help will be appreciated.
Heads and combo chassis are basically the same, except the speaker jacks and some other minor details.
The main difference lies in the production years.
Is it a G 100 I , II , or III?
What problem are you trying to solve?
I think it's good that I can say there are no problems detected with this amp head. I just would like a schematic for future reference should I need it. Not real sure whether it's a I, II, or a III since I find no designation anywhere on the unit. I will do some more research tomorrow and maybe even post a pic here.
There's a lot of discussions about them, just use google.
Cosmetics are very different and help ID them.
http://music-electronics-forum.com/attachments/11058d1285307419-g100-service-manual.pdf.
I think this is the correct schematic for this amp. Unfortunately, I still have not determined whether it's a I, II, or III. The case matches exactly and I have seen several that are completely different from what I have.
OK. I have determined this IS a I head. The II has a different cloth on the front, and the III has what appears to be stamped medal. I also found one with a ser.# in the 1700's, made in '79. Mine is numbered in the 2100's.
Cool, post a couple pictures of yours.
Excellent amp, but always be sure to use good speaker cables and proper cabinets.
Although it has short circuit protection, they are never 100% effective, and repairing that amp may be a nightmare so be doubly careful.
I have tested this amp thru a Randall 4x12 cab a friend has and it just great. I have plans to use a couple of Celestions I have that are not busy right now for a 2x12 to run it with. Since I have no use for a half stack, I can get by with the 2x12 and not run at full blast. Yet, another project for the warden (wife) to complain about. Here is a couple pics:
Thanks for posting.
Cool amp, very loud and clean.
It's a "I" , although usually the "1" of anything does not get a number ;) , they get one when there's a new version and people want to distinguish between them.
If your 2x12" has 2 good 75/80W speakers (or better) you can use them without fear.
The original combo used 2x12" speakers.
Series I= discrete (JFET/BJT) preamp circuitry.
Series II, III= op amp-based.
Hope it helps!