Anyone Using .022uF Cap on Post OD Tone Control?

[ayan]

In a quest to get more of a Fendery sparkle on my clean sound, I ran my master (bypassed with a 68pF bright cap) volume lower than usual at a gig I had yesterday and I really like the results. Of course, that meant that the Overdrive tone was brighter as well, and way too much so for my taste. I have my old .001uF cap after the OD connected to ground through a 1 Meg trimmer set at about 380K at present. Obviously dialing that down some more would reduce the lead sound brightness, but there is something about it that doesn't sound ideal to me. The sound gets squashed, honky, I don't know how to label it.

So, my question to you all is whether anyone uses a .022uF for that, as Dumble did in a couple of amps? That is something I have not tried myself.

Thanks,

Gil

[FUCHSAUDIO]

That sounds big (huge actually) Gil. I've liked a 500-K pot with a .003 or .0047. Not much bigger or you get a really muffled sound.

You really just want to shave off the extreme edge, not more imho.

[ayan]

Hi Andy! I would definitely agree with you and that's why I always used smaller values (.001uF in my case). But I got curious and looked at my notes/archives, and saw that the likes of 94 and 123 used a .022uF cap. That's why I asked about that specific value.

Cheers,

Gil

That sounds big (huge actually) Gil. I've liked a 500-K pot with a .003 or .0047. Not much bigger or you get a really muffled sound.

You really just want to shave off the extreme edge, not more imho.

[Charlie Wilson]

Gil, yeah #94 has the .02 but there isn't much high end to be shaved off. I think I prefer a .002. The high end just seems a little more natural to me with that value.
CW

[talbany]

Gil
I've tried a bunch there and usually go back to a .0047 (using Celestions) and 500k..On my bright 50 watter I have it on the outside and adjust it all over the place depending on room and guitar..Good luck..

Tony

[glasman]

In a quest to get more of a Fendery sparkle on my clean sound, I ran my master (bypassed with a 68pF bright cap) volume lower than usual at a gig I had yesterday and I really like the results. Of course, that meant that the Overdrive tone was brighter as well, and way too much so for my taste. I have my old .001uF cap after the OD connected to ground through a 1 Meg trimmer set at about 380K at present. Obviously dialing that down some more would reduce the lead sound brightness, but there is something about it that doesn't sound ideal to me. The sound gets squashed, honky, I don't know how to label it.

So, my question to you all is whether anyone uses a .022uF for that, as Dumble did in a couple of amps? That is something I have not tried myself.

Thanks,

Gil

I use a .0047uf with a 1 Meg control. I would suspect that the .022uf would make the amps overdrive signature pretty dark.

But with the 68pf on the master you might get away with it, I have found as of late that I really don't care for bright caps on the masters. I find that they throw the balance of the tone off. I find the results much more pleasing with no bright cap. Of course, this is on amps with internal loops. YMMV.

[ayan]

Thanks for all the responses. It sounds like most of you did what I did and never bothered with the .02 cap! 😀

Gil

In a quest to get more of a Fendery sparkle on my clean sound, I ran my master (bypassed with a 68pF bright cap) volume lower than usual at a gig I had yesterday and I really like the results. Of course, that meant that the Overdrive tone was brighter as well, and way too much so for my taste. I have my old .001uF cap after the OD connected to ground through a 1 Meg trimmer set at about 380K at present. Obviously dialing that down some more would reduce the lead sound brightness, but there is something about it that doesn't sound ideal to me. The sound gets squashed, honky, I don't know how to label it.

So, my question to you all is whether anyone uses a .022uF for that, as Dumble did in a couple of amps? That is something I have not tried myself.

Thanks,

Gil

I use a .0047uf with a 1 Meg control. I would suspect that the .022uf would make the amps overdrive signature pretty dark.

But with the 68pf on the master you might get away with it, I have found as of late that I really don't care for bright caps on the masters. I find that they throw the balance of the tone off. I find the results much more pleasing with no bright cap. Of course, this is on amps with internal loops. YMMV.

[Charlie Wilson]

Actually Gil I did try it and can't say I hated it in a Low Plate Classic. I am still convinced that the hf taper rolls off high end in the clean side also and with that value it is very noticeable in my amp. One theory about the .02 in 94 is that it works in conjunction with the 1 meg OD trimmer.
CW

[ayan]

Gotcha, Charlie. Well, I tried a bunch of things for a couple of hours. I did not change my ratio pot, which is 100K. I appreciate the fact that a .02 uF cap HF taper will work different in conjunction with a 1 Meg ratio pot instead. Having said that:

1. the .02uF cap is weird. Turning the trimmer down at some point starts to make the amp crunchier, if that makes any sense. When the trimmer is low enough, of course it makes the lead channel sound muffled.

2. Between .001, .002, .003 and .005, .001 and .002 work better for me. Higher than that, there is something strange that begins to happen in my amps to where the sound loses a bit of its singing quality and also begins to sound crunchier, although not as much as with the .02 uF cap.

3. The 68pF master brightness cap works well for the clean, but it really throws some wrenches on the overdrive no matter what.

4. At the end of it all, what I liked the best was flipping the preamp bright switch on, which for me engages a 120pF cap, turning the HF trimmer all the way down (i.e., bypassing the 100K ratio pot with a .001uF cap), and turning the master high enough to negate the effect of the 68pF brightness cap. The sound is actually very, very cool this way on both clean and OD, and I would say the best I can get out of my amp. It would be very cool to have the silly trimmer on the outside of the amp so that I could A/B the "normal" amp configuration VS this one at a gig. Not to make anyone waste their time messing with their amps, but this may be worth checking out for some of you if you like something like Eric Johnson's chimey clean and very smooth overdrive with screaming highs and soft and spongy lows.

Cheers,

Gil

Actually Gil I did try it and can't say I hated it in a Low Plate Classic. I am still convinced that the hf taper rolls off high end in the clean side also and with that value it is very noticeable in my amp. One theory about the .02 in 94 is that it works in conjunction with the 1 meg OD trimmer.
CW

[ayan]

PS: I remember this from quite a while back. I didn't understand it then and I still don't! I don't hear anything in my amp and based on the schematic, I don't see how anything in the OD chain could affect the clean unless there is some cross talk in the channel switching relay or some unintended connection on the relay PCB.

Gil

I am still convinced that the hf taper rolls off high end in the clean side also and with that value it is very noticeable in my amp. One theory about the .02 in 94 is that it works in conjunction with the 1 meg OD trimmer.
CW

[Charlie Wilson]

Yeah Gil I stared at the schematic till my eyes crossed and the only thing I can think of is the power supply. My amp has been completely rebuilt(not for this reason) and still the same effect. It is pretty subtle but I do hear it. I thought I was going nuts and then Marcos confirmed a similar effect. The effect happens also when I increase the snubber values. I know I have belabored this topic but I hear it and cant deny it and do not think there are any issues with the amp.
CW

[marcos]

Yeah Gil I stared at the schematic till my eyes crossed and the only thing I can think of is the power supply. My amp has been completely rebuilt(not for this reason) and still the same effect. It is pretty subtle but I do hear it. I thought I was going nuts and then Marcos confirmed a similar effect. The effect happens also when I increase the snubber values. I know I have belabored this topic but I hear it and cant deny it and do not think there are any issues with the amp.
CW

As I have said a number of times, I have found that implementing a post-OD
tone control, regardless of cap value or setting, has a subtle effect on the clean tone. I felt that circuit with the .02 cap discussed here was quite noticable in this respect. BTW I tried this circuit a long time ago,
I liked it best with the pot at maximum setting, it still rolls off some
high end.

Marcos

PS: Speaking of subtle effects on tone, whatever happened to Dogears?

[Structo]

I remember when the taper circuit was discussed quite a bit.

The #94 and #102 had a 5K trimmer with a .002 or .003 cap.
Or at least that is what some schematics and layouts show.

After Gil had posted about it I incorporated that into my 100w ODS to curtail the fuzzies on OD.
Works great.

I can't remember what values I used but probably the above with a .002.

[glasman]

Yeah Gil I stared at the schematic till my eyes crossed and the only thing I can think of is the power supply. My amp has been completely rebuilt(not for this reason) and still the same effect. It is pretty subtle but I do hear it. I thought I was going nuts and then Marcos confirmed a similar effect. The effect happens also when I increase the snubber values. I know I have belabored this topic but I hear it and cant deny it and do not think there are any issues with the amp.
CW

As I have said a number of times, I have found that implementing a post-OD
tone control, regardless of cap value or setting, has a subtle effect on the clean tone. I felt that circuit with the .02 cap discussed here was quite noticable in this respect. BTW I tried this circuit a long time ago,
I liked it best with the pot at maximum setting, it still rolls off some
high end.

Marcos

PS: Speaking of subtle effects on tone, whatever happened to Dogears?

Doesn't sound right, the control Gil is talking about in on the Overdrive Level or ratio control, which is out of circuit in Clean mode. I would understand if it was connected to the Master control.

Gary

Dogears is around, check The gear page, he just got a new Collins and has a renewed playing interest.

[glasman]

FWIW, it is a hell of a lot easier to tweak that control when it is a 15 or 30% audio taper. Linear controls make it like you are adjusting an HRM board in a HRM clone.

Gary