DRRI bright cap mods

[TeleBrew]

Some of you may have seen this listing on ebay already. There's a nice DRRI for sale with a bright cap mod to improve the sound of his OD and distortion pedals. The seller added an on/off switch to the bright cap on the tremelo channel rather than snipping the cap.

Is this a good mod to do? Is it something any decent amp tech could perform?

Does a bright cap mod make a big difference when it comes to the sound quality of OD/dist pedals?

[Telenator]

I did it on my '77 Deluxe Reverb. I turn the cap switch "on" for guitars with humbuckers and and "off" for my guitars with single coil pickups. It makes a real nice difference. I know most people just snip the cap off the volume pot entirely but I find it works best when you wire it to a switch. As for OD pedals? I dunno.

[xjazzy]

Do you have a pic of the final result?
I did the bright cap mod but when I'm using clean sounds allways seems that something is missing. I wish I could have another DRRI just for the cleans.

[TeleBrew]

Originally Posted by xjazzy

Do you have a pic of the final result?
I did the bright cap mod but when I'm using clean sounds allways seems that something is missing. I wish I could have another DRRI just for the cleans.

The pics just show a toggle switch on the back of the amp, left side.

[xjazzy]

Yeah, I saw that. I was asking Telenator.
I was thinking how to do that putting the switch in the place of the 2nd input...

[PhatTele]

Actually, that's a great way to do it! The ground switch on the DRRIs is not connected to anything. It's just there for cosmetics. You can repurpose that hole and switch to act like the bright switches on the larger amps. The only difference is that the larger amps use 120pF caps which are actually brighter sounding than the smaller 47pF cap used by the Deluxe Reverb. Good mod idea!!

[CLAZ]

I actually like the 47 in deluxe reverbs! for both clean and OD.... I usually run the OD tone Knob dark to compensate (about 9 oclock).

I am fixing to try a 87pf in a 120pf position in one of my bigger BF amps to see if that makes any diff in OD tone.....

Claz

www.myspace.com/claywillismusic

[Telenator]

I cut a small rectangular hole in the back panel of the amp chasis and drilled two tiny mounting holes. Then I mounted a small slider switch from Radio Shack back there.

Then I cut one leg of the cap off the volume pot and left one leg soldered.

I soldered a wire to the pot where I had clipped off the cap lead and ran it back to the switch.

Then I soldered another wire to the free leg of the cap and ran it back to the switch.

Now, when I throw the switch, it either includes the cap in the circuit, or omits it.

It's a very useful mod that really helps dial in the exact tones I like from my
'77 SFDR.

I include the cap in the circuit for my humbucker guitars, and omit the cap for my single coil guitars. It works great!

I know some will cringe at the thought of my cutting a small hole in the back of a vintage amp but, oh well, I love the amp more than ever now and it sees a lot more action these days because of the mod.

[xjazzy]

Another ida is to replace one of the knobs with a push-pull.
Gonna talk to my amp tech to see what he thinks

[PhatTele]

With regard to the pushpull pot idea...it's pretty easy to do on a SF or BF model. However, it will be a PITA to do with the reissue model since those pots are hard wired directly to the circuit board.

[xjazzy]

Anyone can show me some tuturial of how to connect a switch for this?
I was searching on the net and there's thousends of different switches and they all have a lot of contacts and I really don't know how to connect the wires to the switch!!!
Thanks.

[theUKinthe80s]

I just did the bright cap mod on an Ashdown Peacemaker 40 amp. That amp had an unbearable amount of treble (even when the treble knob is on zero). The mod makes the treble alot more controlable. The amp is useable now.

[ThermionicScott]

You know what would be cool? A three-position slider switch with 47pF, 120pF, or no cap as options.

I really like the 100pF bright channel in my 5E7 for some tones -- it gives you extra treble to play with, without being "hissy."

- Scott