Towry Guitar & Amp Service & Repair

07/24/2021

Why am I getting posts from Jennifer Lopez, Adam Carolla and such and not from my friends? I don’t want posts from movie stars.

01/29/2021

09/26/2019

I've seen lots of posts on the web about adding reverb to a Fender Bassman head. The Bassman is one of the greatest tube amps for guitar but there's always the problem of reverb. Should you use a reverb pedal or a complete tube/spring reverb unit?

Well there are several Bassman models that can be "reverbed" if you know an amp tech who can do it.

The problem now is, do you want to mod that vintage Bassman just to have a great sounding head with reverb.
I have a '68 Bassman Silverface which actually has the same circuit as the Blackface. I certainly don't want to go modding that jewel however I also had a bassman 50 given to me, a 1977 that I was willing to sacrifice for a good "work" amp.

Of course for guitar you don't need the bass channel just the normal channel.

So I gutted the bass side which uses one 12AX7 and also there is one half of another 12AX7 tube that is vacant (not being used). So for a reverb circuit you need one whole tube socket for the reverb driver and a half tube socket for the return.

Bingo. Just gut the bass channel of all components and there you can build a complete reverb circuit using a 12AX7 for the driver and a 12AT7 for the return. Of course you'll also need a reverb transformer and tank. A short reverb tank just fits in the Bassman head cabinet and there's room for the reverb transformer between the two tube sockets. Have your amp tech install the components and a reverb pot and you're in business.

07/27/2019

I've seen lots of posts on the web asking how to add reverb to a Fender Bassman. Most say it's too costly, too complicated or suggest using a reverb pedal. The problem is you can't add more tube circuits because you will be drawing too much current especially in your filament circuit but on some Bassman amps you can sacrifice the bass circuit for the reverb and run your guitar into the normal circuit. First you have to decide, do you want to mod your Bassman or is it too valuable. I have a '68 Bassman head and a Bassman 50. the 50 was given to me in a "not working" condition. Any well qualified amp tech can do this mod if its the right Bassman. (Note: Not all Bassmans will work). I did not want to mod the '68 but the 50 was a 1977 and I was ready to mod it and add reverb.The bass channel uses one 12AX7 and there is one half of another 12AX7 that is not used in this particular amp. I used these tube circuits for the reverb. I had to settle for a short tank to fit the Bassman head. It sounds great. All of the circuit has to be stripped of all components and a new circuit built. A reverb tank and reverb transformer are the only major purchases. Of course the 12AX7 is replaced with a 12AT7 for the reverb driver.