Ampeg V4 restoration pt.1

Here I explain the basic features of a late 70s Ampeg V4 as well as point out inner details of electrical refurbishment.

[@jayletter5209]

The "6550 upgrade" was only for the "distortion" model. It has the different power transformer and a separate winding for the screen supply (340 volts). The standard V4 will put out slightly less power with 6550's.

[@DanielMartinez-is6rb]

Thanks for the video. There is not a lot of info on the V4. This will help me figure out what to do with this amp. Rock on.

[@jothanankrogh]

That's great Daniel, as complex as these look inside, all they usually need are the basics. Electrolytics, diodes, the bias circuit and then tubes as necessary, bearing in mind most tubes cant handle these amps voltages. I really do feel 6550s are the right thing for them.

[@RandallDibble]

Thank You for Your Efforts ! I have Ampeg V4B 1972. Keep the Video's Coming.

[@tonymanns8249]

I bought an early '70's Ampeg V4 amp about 4 years ago. I used a V4 in my band back in the '70's when I played music for a living. I liked the amp but I traded it in for a Fender Super-Reverb amp because it was too loud for the smallish rooms to which my band was playing. Replacement front control panels are available for the V4 and mine needed one.

[@tonymanns8249]

My Reverb.com Ampeg V4 purchase came with EL34's instead of 7027a's. I rewired the amp for 7027a's and I installed JJ 7027a's. Also, thankfully someone in the past installed a bias pot. When I opened up the amp to inspect the circuitry I was disappointed to find PC boards instead of Fender-esque hand-wiring. Apparently Ampeg was unfortunately ahead of the industry in using PC boards. :( Otherwise it is a very good and attractive amp that uses some almost extinct tubes.

[@declanmctiernan7338]

Hi Jonathan, what are your go to capacitor brand/series when replacing filter capacitors or capacitors in the preamp section. I'm looking at restoring an Ampeg SVT 3 Non-Pro.