Ampeg b25 help

[angelothewolf]

Hi there!,

Im struggling with this Ampeg B25. bad 120hz hum I cannot find the culprit. It came with original caps, some bias trimpot mod. I thought...

[angelothewolf]

Thanks Enzo, Im getting mad with this sh*#$
this is my DC measurements comparision,

PIN# // working VCO...

[angelothewolf]

Hi folks!
Im with this roland jupiter 6 on the bench, so far so good, then I get stuck trying to toubleshoot this issue. Aparently I have two voices...

[angelothewolf]

Hi Im desperately looking for the Midas 3000 legend service manual. already contact Musictribe group and they dont want to sell it. Did any one knows how...

[angelothewolf]

Hi there!

So, it is an Ampeg BA600-115 it came with a massive electrolyte leakage from a filter capacitor (C16) that exoplode after some PSU...

[angelothewolf]

Hi there, just to update. Now I have all the pieces to mount this amp. Im using that gibson transformer wich has a 720VAC HT secondary, so Im thinking how...

[angelothewolf]

Now im considering using a transformer at the input but Im not shure about the ratio and impedance......

[angelothewolf]

Well, the thing is, I might be wrong, but I think this is not a bad preamp at all. For example I can't see too much differences between this circuit and the...

[angelothewolf]

The only info I have about the ICs are the datasheets, and the complete schematics of the Akai preamp.
I omitted completely the last transistor stage...

[angelothewolf]

Hi friends!

Im working on a project. It is basicaly a ballanced rack version of the Akai 4000DS MKII microphone preamp. I have some thoughts...

[angelothewolf]

I ended up repairing this Crown ( macrotech600) with the transistors of a Macrotech 3600 that I have from waste. I use C8188/87 output devices and to220 2SA1837/2SC4793...

[angelothewolf]

Hi there! was a long time ago, but as I remember we end up buying a replacement amplifier PCB> LINK...

[angelothewolf]

Hi there,

im working on a Crown Macrotech 600, canīt find the schematics.

BTW I got a hole set of C8187/C8188 Crown output transistors...

[angelothewolf]

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[angelothewolf]

Hi there, so, im planning to use the gibson OT and 7591 instead the 6V6s. 5E11 circuit except for the bias negative supply wich will be from the 6G11-A circuit...

[angelothewolf]

I bought an old Peavey Classic 30. With a fried PT. The original idea was to restore it and keep it for myself. Then I take it apart, and when i saw that...

[angelothewolf]

great! I personally like more the 5F11, I have the Gibson output tranny too! I think the only modification of the stock circuit would be the negative supply...

[angelothewolf]

Maybe a 5E3 would be a better choice......

[angelothewolf]

Yep was what i think too, maybe the RCA has the current capability too... But what about that tap on the HT winding that goes to the "Depth" pot??...

[angelothewolf]

Hi there.

I have this three trannyes for my Fender 5F11 project. I wonder if any is suitable for the job?



from...

[angelothewolf]

Nice, this is the right way to do it. I think I can build for him a mono fader in a box with XLRs and he will be happy...