Tube swap in a Mesa Dual Caliber 5

[Burt Reynolds]

I have a 50w boogie dual caliber five with two 6L6's in the power section that I run with a 100w stiletto rec- I'm thinking about taking it to my amp dude and having him retrofit it with KT-66 tubes. I might have to have him switch some shit around to make it work, I know they're fixed bias but you gotta be able to modify that. there's a push/pull gain boost too if I could have him crack out the boost and put in the 66's I think I'd be in fat city.

figured I'd see what people think about the feasibility of a job like that.

I could probably get it done (tubes not included) for a hundred or two.

I got the amp for free because it was 'broken'- so with new tubes and the fix, I got about 200 in the thing.

[charvel750]

Well, if it's fixed bias you might be ok just switching in the KT-66's. If you have a bias probe you can check the current plate voltage and current draw of the existing 6L6's and then install the KT-66's and see if the draw is good within that plate voltage. Might not need any adjustment at all. Example: suppose the present plate voltage is 470 V and the present 6L6's are in bias at 37 mA. Then you put in the KT-66's and find the plate voltage at say 500 V, with draw at 35 mA. Well, that's in proper bias range and you'd be good to go. If you have that ability try it and just see.