JCA22H mod recommendations?

  • Thread starter Thread starter ledvedder
  • Start date Start date
ledvedder

ledvedder

Well-known member
I have a JCA22H head sitting around collecting dust. I'd like to do some mods to it, so I'm looking for some ideas.

I'm thinking something clean to slight breakup on the crunch channel. Then, either SLO or some type of BE on the overdrive channel.

What's your recommendations?
 
The SLO won the most overated amp thread (unsubstantiated of course). That’s exactly what I’d do
 
I can't seem to find a schematic for the SLO mod on a 22h.
 
ledvedder said:
I can't seem to find a schematic for the SLO mod on a 22h.
Click to expand...
Should be doing the same as you would on the 50H. It's just the first couple stages and gain pots you're swapping values of. I'll send you a 22H schematic over FB if you don't have one.

You can also do a gain cut switch that acts sort of like a 'clean' mod on the Normal channel. Standard on the Soldano SLO front panel.


Screenshot_20180207-080551~2.png
 
sahlomonic said:
Should be doing the same as you would on the 50H. It's just the first couple stages and gain pots you're swapping values of. I'll send you a 22H schematic over FB if you don't have one.

You can also do a gain cut switch that acts sort of like a 'clean' mod on the Normal channel. Standard on the Soldano SLO front panel.


View attachment 139861
Click to expand...
So it needs to be done to the crunch channel? I'd prefer it on the OD channel. I'm trying to go for a clean to mild drive thing on the crunch channel.

I have the JCA22H schematic, but it's a pain to reference. It just has the locations, not values (R12, C11, etc). Then I have to reference a different chart for the component values.
 
ledvedder said:
How different is the SLO from the BE?
Click to expand...
You can apply the gain cut on the OD channel as well. Short, short answer: BE has higher plate loads on the first stage, different cold clipper, and the gain pot is in another gain stage further down than SLO. I mean, it's very different, but also not that different.

The Custom22 and 50H schematics I have show the values, and should be the same as the 22H (C22 is just slightly different in a couple areas)
 
JackBootedThug said:
I think there's a good thread about this on the Guitar amp board.....
Click to expand...
There is, but that thread is pretty dead. I try to give it a little life every now and then, but not a lot of dudes posting in there anymore
 
Add a Depth Mod/Resonance to it.

Did that to mine when I had it....along with some other toggles that I already forgot what they did.
 

Attachments

  • Jet City JCA22H modded.JPG
    Jet City JCA22H modded.JPG
    316.2 KB · Views: 112
Crazynutz drew out the schematic as psychodave described it, it’s here on the forum somewhere (for the single channel), but he (psychodav)described cutting traces and using unobtanium parts for some of it…
 
paulyc said:
Crazynutz drew out the schematic as psychodave described it, it’s here on the forum somewhere (for the single channel), but he (psychodav)described cutting traces and using unobtanium parts for some of it…
Click to expand...
Yeah, I've downloaded that schematic. I'm just not sure how it would be done on my 2 channel one.
 
Hey guys! I just got jca 22h Wednesday and love it. I traded in my tubemeister 18 and a Blackstar 1X12 for it and a Mesa 2X12 compact with the UK vintage 30s. This thing has some authority! In reading the manual, it seems the clean channel is engaged by lowering the pre amp crunch and overdrive. Is this correct? There also seems to be some hiss and hum on this amp when increasing preamp and master overdrive ( but mostly master overdrive). Is this normal? Is there a mod to help alleviate this? This is with humbuckers and of course is more pronounced with my P94s. Any advice would help. Thanks
 
You must log in or register to reply here.
Back
Top