Some time ago, as you can see here: http://forum.metroamp.com/viewtopic.php?f=3&t=43130
I bought a JMP 2203. The amp was not bad, but it had some "tweaks" that I didn't like it and I restored back to a more usual 2203.
But after playing some days with my band, I realized that 2203 is not for me and I was decided to change it to 1959 circuit, that is what I really like.
This is how the amp came. This is an american model, with 6550 tubes, and recapped with some polypropylene caps. The board and the wiring was a little messy:
Better view of the board. As you can see the recap was not very neat...
I removed the polypropylene caps and replaced it with some Phillips mustards for PCB. Put a 1k5/330uF in V1A (I prefer 1k5 'cause is clearer). I found some Pihers in a drawer and the old 330uF from another 1959 that I modded.
I also put a .68 Sozo across V2a cathode, 100nF Mustard on presence pot, brand new Alpha pots (the old ones was scratchy), converted to EL34 and changed the 47pF across the PI for a 100pF that I like more.
As you could see in the previous photo, I also installed a Dual Lar/Mar. I copied the 2555 circuit for relay supply.
I also rewired the controls part. Now is cleaner. (in the pics you can see a bright cap across the normal channel pot, but I removed it, it was just only and experiment
)
Hope you like it.
Suggestions accepted!
