What I'm thinking of for a switchable tone stack would be to start with the stock OR15 components and using a 4PDT switch, you would need to wire all the components in parallel with what is already there. -500pf caps parallel to the stock 470pf caps for the treble. This would give you 970pf on each ...

I found that the Tung Sol worked best too. For a little more versatility, try a 5751 in V2, you'll lose some gain (but there is still a lot available) and it made it easier to dial in lower gain tones if that's something that may interest you.

Man1ak wrote:Thanks man, that's great! I fancy installing the #4 tonestack in my OR and make it switchable. I'll talk to my tech buddy to see if it's feasible. These small amps are soooo crowded...

Let me know how it works if it can be done. It would be pretty sweet to have essentially both amps.

Congratulations man! It's good to be happy with your amp :) Why would there be a problem to post the values of the new caps? Not sure if it violates the rules or anything. But if it does it will remove it. C7 was changed to 4n7 680v, C11 and C12 are now 1n 1kW and lastly R17 is now 39k. I played a ...

Thanks for the comments. When my neighbors leave and I can turn it up some I'll record a demo. Cool stuff! Did you hit C14 with the soldering iron? Beware it could eventually fail. Yeah, one of my dogs decided he wanted to play while I was soldering and I burned it a bit. It's not nearly as bad as i...

With the help of a friend, I was able to convert my OR15 to Jim Root Terror specs. By swapping out the treble caps, slope resistor and the coupling cap (C7, I think it's the coupling cap, still fairly new on the technical terms) on the second gain stage and the results are fantastic. I'm not sure if...

I don't get it... Why not getting a #4 instead? Saves you ruining the resale value of your OR15 and ensures you get an amp that sounds like the #4 I've been trying to trade it for a while with no luck and I can't afford to take a hit financially by selling it, so I decided to give modding it a shot...

Are there any other differences in the OR and JR preamps besides the slope resistor and treble caps? I can't find a schematic anywhere. I'm in the middle of "converting" my OR15 to sound a bit more like the #4. So I was wondering if there were any other variations in the tone stack. Any help would b...

Well, the Dark Terror, Jim Root Terror and OR15 are the same amp with different tone stacks. That's why I was telling you to try changing the EQ section. It should be more versatile than the Dark Terror due to 3 band eq vs shape control. I read that by changing the slope resistor you can alter the ...

As much as I love this amp, I think I should have stuck with my Dark Terror. If I could get a little more of an aggressive tone out of it to go with how easy it is to dial in a great blues tone, I'd be set. The OR15 does sound similar to the Dark Terror with the mids scooped, but it's still lacking ...

So after reading the OR15 diagram and the thread about the differences between the JR and OR15, if I changed out C13 to a .1uF cap it should get me a little closer to what I'm looking for in low end, or am I still missing the mark here?

OR15 Metal Riffs... just because it can do pretty much everything and do it well. Orange OR15 and PPC112 (V30) and a PRS Singlecut Trem with a DiMarzio Crunch Lab and LiquiFire. 15 Watts, Volume 9:00 First Riff: Treble: 4:00, Mids:11:00, Bass: 2:00, Drive: 3:00 Second Riff: Treble: 4:00, Mids:0, Bas...

Thanks Andy, I did a little more EQ'ing and I think I'm where I want to be with it now. Not to say I wouldn't want to revisit a mod or two down the line (after some reading... thanks again Jon). I had a Dark Terror before this but I found it difficult to get a lower gain sound I wanted without havin...

Thanks for the link to the other thread, I'll have to check it out later on. Page three of this thread mentioned some similarities to a JCM800 a few times. I love the over all tone of the OR, I don't really want a drastic change, I just think the depth mod could be beneficial for more variation in E...

Thanks for the information Jon, I'll have to get around to reading it. What I'm trying to do is boost bass frequencies, like how Jet City JCA20 owners have been doing to tighten up their low end. Apparently JCM800 owners have been doing it as well, since I've read that the JCM and OR15 are similar, ...