Any reason not to install a choke on TA-15?

[talltxguy]

Other than voiding my warranty, can anybody think of a reason why I would not want to have a tech install a choke on my TA-15?

I'm gonna see if he can put a switch so that I can go back and forth between the resistor and the 5-H choke from Mercury Mags.

 

[rabies]

dude, you're wasting your time and money in all probability.

you don't need MMOT, etc. with Mesa. just play the damn amp.

 

[J.J]

Other than voiding my warranty, can anybody think of a reason why I would not want to have a tech install a choke on my TA-15?

I'm gonna see if he can put a switch so that I can go back and forth between the resistor and the 5-H choke from Mercury Mags.

The "Dyna watt" setup in the power supply complicates things, but You'd have to try it to see what happens.

I suspect it won't be worth the effort. If you want to play and haven't rolled some tubes I'd suggest you money would be better spent in that area.

 

[talltxguy]

I had taken my amp to a Mesa tech in Austin because I thought the amp was messed up. Turns out that it was either a cab or a cable. Anyway I'm going to have the tech see if there's room for a choke as I do have one. Hey, I'm a toneseeker...what can I say?! 8)

 

[talltxguy]

My tech told me that he spoke with Mike B. at Mesa about installing a choke on the TA-15. A choke can be installed but there's a catch. The amp will only be able to run in 25 watt A/B or 15 watt push-pull A. I'm gonna have the 3-way power amp switch changed to a 2-way switch so that I don't accidentally knock it into single-ended class A and ruin things.

I'm sorry that I can't intelligently explain why single-ended class A won't work if a choke is installed. My tech explained it to me, but it was a bit over my head.

Anyway the amp should be finished next week as my tech was out of town. Hopefully, things will work out nicely. I'm very curious to hear the amp with a choke installed!

 

[talltxguy]

Well I'll be picking up the amp on Friday. He said he's about done with it, and I haven't heard anything negative; so sounds like it's gonna fly.

 

[talltxguy]

Gonna fool with it for a while and tubeswap. Will post some results of tone, dynamics, etc. after getting a few hours on it. The plate voltage did drop about 8 volts in 25 A/B & 15 class A.

Here's a pic of the choke.

 

[talltxguy]

Had an opportunity to let the amp rip today with a drummer and bassist at the practice space. The amp sounds better and plays better. Interestingly enough, the distorted channel has more gain than it did before. The tech explained that when he did the work, voltage would drop a tad in the output tubes, which it did (8 ma) but for some reason above my head the voltage increased a bit in the preamp tubes. The clean channels sound really good and are not as brittle. I think it's a pretty good mod to do if you don't mind the goofy location of the choke. :?