Variations on Steve’s Mod?

[sh60bmurph]

Hi everyone. Having a need to crack open my 2266 to swap out a bad FET 3 on the effects loop, and a burnt out pilot light, I figured I finally had the opportunity to try “Steve’s Mod” for that something “more”. So I ordered a Vishay aluminum electrolytic 1uF cap for C1 and a Vishay .0022uF film cap for C2 from Mouser Electronics.

Results: Definitely got the additional gain and beefiness I was looking for (80’s Rock), but felt I lost a little in the amp’s dynamics or clarity in the gain. Almost feels like there is a blanket at the end of the notes or chords. Wish the amp would breath a little more with the new found gain. For what is worth, I exclusively use HDR and run the 2266 thru a Suhr Reactive Load via IRs or reamped w/Carvin FET 450 power amp into a 4x12 w/Greenbacks.

So now I am on a quest to find something in between the stock VM and that of Steve’s Mod. Therefore, before I start ordering a bunch of parts and going down rabbit holes, I would like to hear from those who already warmed up their soldering irons on VMs, and get their take on mods to V1.

Based on my desire to keep the new found gain, but get some of the dynamics back, I think I should start by changing C1 to a .68uF, and keep C2 at the mod value of .0022uF. From my internet research, I believe this would raise the shelving freq, thus possibly cleaning up the lows that might let the amp breath a little more, yet keep some of the added gain. Would this be correct?

Or, I could keep the mod value of 1uF on C1, but start experimenting with a different value for C2, say a 1500pF? My only concern is that I do like the “fullness” that I think the mod C2 value brings.

Or maybe I should go with the traditional Marshall values of .68uF/2.7k/.0022uF for V1a. But understating there is a symbiotic relationship with the other parts down the line, so this combo might not produce the expected results.

This forum has been an awesome inspiration and one of the reasons I bought a VM. So thanks ahead of time and look forward to your comments.

[surfnorthwest]

I think using the Suhr Reactive Load would defeat any sonic changes you would hear making those mods. Those mods would be subtle in what you hear so would be best to experiment. Unfortunately that means doing surgery on the amp multiple times.

[sh60bmurph]

Thanks for feedback Surf. Totally agree that much tinkering will be required. Should be fun.