Ampeg PF50T service manual needed

[Tone Meister]

Need service manual for Ampeg Portaflex 50 Tube bass amp

[doctor]

There is no service manual for this model, only schematic.
See in your PM box.

[camjenkins]

Is there any reason why you can't post it here? I've been looking for the schematic too for quite some time.

[g1]

Usually because of non-disclosure agreements. This means if you publish them on the web you lose all your privileges with that manufacturer.

[vintagekiki]

http://mnats.net/ampeg_pf-50t_hum_buster.html

[marsbel]

Hello,

Any chance of getting the schematic too? I'm very interested what it looks like.

Mark

[Jazz P Bass]

http://mnats.net/ampeg_pf-50t_hum_buster.html

Really a good article.
Thanks!

[g1]

Really a good article.
Thanks!

That was good, but after all that work he was about to change over from rheostat type and take the bias off the pot wiper. No, no, no!
Good thing the guy from talkbass came along and showed how to do it and keep the much safer rheostat version.

[The Dude]

You also gotta love that he put that electrolytic cap directly on top of the 5W resistor.

[g1]

Mr. Theory needs to be introduced to Mr. Practice.
I'll bet he has some letters after his name.

edit: nevermind, the cap over resistor was done by the talkbass guy, even though he had the better circuit.

[Chingiwingi]

Hi,

I'm looking for the Ampeg PF50T service manual, a schematic would also be good.

Thank you very much!

[keyofnight]

Hey there! Can I get a copy of the schematic too? I'm trying to figure out a mod.

[Rutherberg]

Hi, I'm searching for this schematic as well. Could someone PM it to me ? It would be greatly appreciated !

Thanks

[polymorphorism]

Hello, could someone please PM me the schematic as well for the PF-T50? I'm trying to extend the low frequency range a bit...

Thanks in advance!

[Chuck H]

Well the last four posts on this thread have been many months apart from first time posters requesting a schematic. I'll have to say that it really doesn't look like one is coming guys. That said...

polymorphism, I can't imagine the amp wan designed with a limit on what it could reproduce in low end. That's really nothing anyone would do designing a bass amp. To put it succinctly, and unless I'm shown otherwise I don't think circuit modification on the amp will extend the bottom end usefully. You may be able to boost it into distortion, but not likely you'll get more and louder with a free pass or they would have done that in the first place. So...

Try a different speaker or speakers. Plug it into a different cabinet known for extended and pronounced low range. Experiment with this and you may find something you can do with the existing cabinet to get closer to what you want.