Yamaha g100 power amp

[edlo]

ok i recently bought an used g100 solid state yamaha amp and the power amp or power supply unit got chard from connecting it to a 220 volt outlet, can somebody tell me what is the correct power amp for this amp, i need to buy one and the technician does not know which one to get......
thanks edwin

[J M Fahey]

There's no replacement power amp boards for it, that amp may be 20 to 30 years old.
It's discrete and will have to be repaired.
Try to determine *which* model (or generation) it is, it was made for over 20 years with variations.
Post a couple pictures, maybe Teemuck can tell you which one is it and even post a schematic.
Good luck.

[bassetrox]

ok i recently bought an used g100 solid state yamaha amp and the power amp or power supply unit got chard from connecting it to a 220 volt outlet, can somebody tell me what is the correct power amp for this amp, i need to buy one and the technician does not know which one to get......
thanks edwin

Do you need a schem? Think i have one at home. EDIT: PM if so.

[teemuk]

If it's series 2 or 3 it is stated in the model designation in roman numbers. The first series understandably doesn't make any notions being the first so it just states something like G100 or plain 100.

If it's a combo model the "100" is followed by a speaker designation and depending on it the preamp design varied. For example in series II amp with a 1x12" speaker config was a single-channel design but amps with either 1x15" or 2x12" were dual channel designs. Details would make a lenghty thread but if you need to hunt down for the right schematics be aware that several ones might exist for "G100": Those for different versions and in addition those with different speaker setups and hence preamp designs.

Anyway, the model names are like this:

- 100-212, 100-410, 100-112, etc. Referring to G100 combo models of the first series. Head version was plain G100.
- Fifty112, Fifty212, etc. Referring to G50 combos of the first series.
- G100-212II, G100-410II, etc. referring to combo G100's of the second series
- G50-112II, G50-212II, etc. referring to combo G50's of the second series
G-212III, G100-112III, etc. referring to combo G100's of the third series.

Despite plenty of variation the naming style is actually quite logical and a good way to cover all variations within different model families, designs within different model families, and versions of different model families.

Anyway, if I remember right series I and II power amp designs were almost identical. The series III power amp was revised quite heavily.

[Enzo]

Just a thought, maybe not accurate...   COnsidering the poster is a layman, and is asking which "power amp" to get.   Perhaps what he means is power transformer.  That sounds a more reasonable thing to ask using the terms like which one to get.

[J M Fahey]

Agree with Enzo.
Problem is that connecting 110V stuff into 220V is a *very* bad thing, very destructive, unless a fuse blows real fast and avoids further damage.
Nothing to depend on, but I *have* seen such.
But the poster is talking of "charred" "power amp" or "power supply" which is a certain possibility and points to no saving fuse this time.
Or even worse, fuse replaced by tinfoil or something and plugged a second time.
So the Tech might really be asking about a new power board replacement.
Dear Edwin, can you please ask the Tech to write something himself?
If possible, we'll help him, but need to know more.
Thanks.