TRAYNOR YBA-3 HIGH GAIN MODS

[Mr.Death]

I recently bought a Traynor YBA-3 with the intention of converting it to a high gain JCM800 style amp. Changes i've made thus far are on the schematic. The final value I plan on changing is the V1B resistor circled in red. I've been researching this for days now and have narrowed it down to 1k or the stock 8.2k but I'm open to suggestions, maybe different values selected by a switch? Was going to use 10k but doubt there will be any difference between the stock 8.2k and 10k. So what are your thoughts on a value for V1B? I play metal and want this amp to melt faces. Thanks
Rick.

[Mr.Death]

Still have to clean up a few things but so far this is how she looks.

[dwinstonwood]

This is a pretty useful tool: https://www.ampbooks.com/mobile/amplifier-calculators/cathode-capacitor/calculator/

I'm currently experimenting with cathode and load resistors (and, bypass caps) on an amp I built with three preamp triodes. I'm not aiming for death metal distortion, but I'm setting the first/input triode to have the largest voltage swing/headroom, and the last triode biased cold to create the most 2nd-order harmonic distortion. I got most of my info from Blencowe's Valve Preamp book. I don't claim to fully understand all of this.

[Mr.Death]

Interesting site. I'll have to play with it and see what looks good. New to this world of amp mods so lots to learn. Thanks

[Mr.Death]

I just want to know what effect the 10k will have compared to 1K for V1B with V1A having 2.7R .68 cap. I'm digging online to find my answer but Im coming up short. I checked out the link above but doesn't work well without a cap added. I'm out of my league here I know. lol. Please guide me. Thanks. In the future I will dig deep and read books on this topic. 

[ShoemanGB]

Bottom line is just solder it in, fire it up and find out.  I get where you're at, and have been there myself, but the theory needs to give way to the reality sooner or later.  Or wire a switch so you can select either easily for comparison.  Not being a smart ass, so please don't take my advice that way.  It's just that only your ears can tell you what you like, and then only with your gear too.  That's part of the fun (or insanity) of the never ending quest for the "perfect" tone.   

[PRR]

1k will distort easier and softer.

10k will be harder to distort but will distort harder.

This stuff is hard to talk about. Why not buy a box of resistors and try many likely values, in your amp, on your speaker, in your venue.

[Mr.Death]

Im going to add a switch and try out different values. Thanks all.

[Mr.Death]

Saw this on another forum.  Friedman sells this mod or did. I bought the components and plan on installing it. 

[dwinstonwood]

Experimenting and finding out what sounds best to you is for sure the right course. That's what I'm doing.
But, researching why it sounds good, and learning what it is that's making it sound good, is a worthwhile endeavor, too.
Then, you can look at other schematics and see what's going on -  "sight reading" a schematic, so to speak. Oh, I can see how that would sound. That's a goal of mine.

[Mr.Death]

Im with you for sure. It would be cool to look at a schematic and say, that makes sense! Should be interesting. etc.. Anyway I started with the switch but had to use a axial cap thats huge as I couldnt find a smaller radial cap. Ill post pics as i go.

[Mr.Death]

Switch is in. It bench tested perfect. Still have to tidy up some wiring and then figure out the proper way to start up an amp that has had all of its electrolytics replaced. I may start another post for that.

[tubeswell]

It would be cool to look at a schematic and say, that makes sense! Should be interesting. etc...

https://www.diystompboxes.com/pedals/tubedummy.html

[Mr.Death]

cool, thanks!

[Mr.Death]

All done. Works as it should.