The Amp Garage

12AYZ tubes in both V1 and V2 will bring the gain down considerably. IF you are using humbuckers try to find VIPots which come on much slower than most 500k pots. This will help quite a bit to get a nice clean tone. Without the very slow rising taper of VIPots (or original Centrlabs) it is much tri...

Thank you for the feedback, guys.

Hey guys, I have a question concerning just how aggressive these amps SHOULD be. I have an amp that began life as an exact Express clone under the name Tonic Vapour. Got it used off Reverb and had to send it to Paul Ruby for a major renovation. Then I put NOS Siemens EL34 and Amperex 12AX7 in it. I ...

Phil/Martin,

Thank you so much for the info! I really appreciate it.

Thank you for the info, Phil! I am planning for my first amp build to be something Fender Champ-ish after my transition back to civilian life is complete. I literally know almost nothing about tube specs so that's something I hope to gain as I'm building. Thanks, again!

Bryan

I'm looking forward to using them. And I don't know for sure, but the appear to be unused.

A buddy of mine found these for sale in my area today. It was a whole box of stuff, most I won't keep, for $30. Suffice it to say, the 12AX7 and 12AT7 tubes make it worth it.

I don't know if it was the power or preamp tubes that cut the hum. I'll have to roll between them to be sure.

I did not bias the amp after swapping tubes. I know that's a must, but I didn't want to mess with it since it's going back for maintenance.

Thanks for the info!

I have a question that I expect is a bit subjective. But if I'm lucky, I'll get some good info. When I got my amp it had all Sovtek tubes in it. It hummed like a MFer but all the tone (typically expected from an Express) was there. Aside from the hum, it was breaktaking. It bought some NOS Siemens E...

Some time ago I built an Express (using a non-traditional layout), and then realized that there wasn't that much difference between it and a 2204, so I used the same basic chassis and modified the board layout to suit a 2204 circuit. I bought a new set of transformers and a choke (which the Express...

sluckey wrote: ↑Sat Oct 23, 2021 9:57 pm

Bryan Cox wrote: ↑Sat Oct 23, 2021 9:26 pm It isn't a faithful 2204. He called it an "Olympic style doping amp," but I have no clue what that means. Any thoughts?

That means he can charge more!

Lol. In my case, he was reasonable. $1400 total cost and it's a beautiful amp.

Several years ago, I had a JMP 2204 circuit built for me by Mark Moser at Frugal amps. (Phenomenal guy and builder, BTW). I love the amp but am now smitten with the Express clone from Tonic Amps. Now I'm wondering, just what would it take to convert a 2204 to an Express? I can provide gut shots soon...

If your still in North Dakota stop and see me, I will fix your amp. Mark Oh, man! I wish I'd posted this stuff sooner. I'd have taken a weekend to come down to Walcott. At this point though, I won't be able to squeeze it in. It's about a 5 hour drive and the AF has me busy as hell up until I leave....

I heard back from Darin. He's thinking possibly filter caps (like Colossal) and/or tubes. There's a bias knob right behind the power tubes, near the PT. Darin suggested I manipulate that a little to see if it has any effect, and it did! When I biased it colder the hum got noticeably quieter. Not qui...

Hi, Bryan, welcome. Do you have experience working with HIGH VOLTAGE circuits? These can kill you. There are three preamp tubes in your Express, and the one closest to the power tubes is the PI (phase inverter). Remove the PI tube and power up--is there still hum? This will give us a helpful clue. ...