"THE" tone without all the knobs

[LeftyStrat]

Just to give you a few more ideas, lately I've been trying to clone the EMG-EXG and EMG-SPC tone controls that Gilmour uses in his strat. (Yeah, I'm a cheapskate and can't see spending $45 a pop for a pot, an opamp and a few resistors and caps. Anyone have a schematic?).

The EMG-SPC goes from flat to a wide midrange boost. The EMG-EXG goes from flat to simultaneously boosting bass and treble and cutting midrange. There's a PDF on EMG's site that shows the response curves.

Anyway, this got me to thinking, most of the time I want to fiddle with knobs, I'm thinking either:

- Needs more/less treble/bass.
- Needs more/less midrange.

The Big Muff tone stack (see Duncans TSC) can do the bass/treble balance thing, but has a big midrange dip. I'm sure you could play with component values to get the dip to be similar to whatever tone stack you are replacing. Then something like the EMG-EXG could vary the amount of dip (perhaps with something active you could even have a boost).

As others have pointed out, the main two reasons for touching the tone controls are either to adjust the amp for a different guitar, or to adjust the amp for a particular room.

You could have two jacks labeled "Humbucker" and "Single Coil" but then you'd just confuse the guys with HSS Strats.

[heisthl]

You just need a Whizzer like Neil Young uses

Or maybe what I really need is the whizzinator. http://www.whizzinator.com/whiz2.htm

[smzinno]

I've never built one of these D-style amps, but here's an idea I used recently. the amp was a 2-channel 4-gain-stage variety, and the user is someone who doesn't deal well with complex amp controls.

on the 'clean' channel there was a drive and a master, period - no tone controls at all. there was a large series resistor to control the monstrous gain after stage 2, with a bypass cap to balance the treble content. the rest would be done using the controls on the guitar.

on the 'drive' channel there was a drive and a master, plus a treble control only. internally, it was a marshall-style tonestack prior to the o/d stages, with trimpots for the mid and bass controls so it could be tweaked.

so, total of five controls with a single treble control that worked only on the o/d. very organic clean tones with a lot of gain available on tap, and pretty heavy 80s-ish overdrive with 'english' tendencies. might have also been workable with the 'tonestack' in the usual location to affect both channels with the treble, but I never ended up trying that.

no clue what it would be like in a ODS though.

[Luthierwnc]

My 2 cents; My only problem with too many knobs is they are hard to see on stage. You can't look back for a quick check. The same goes for push-pull pots. From 10 feet away in bad light you have to guess. If you can clearly see the pointer, you're probably OK.

One thing I do is use one color knob for the critical pots and another color for everything else. That or different colors for the OD and clean. I guess it depends on whether it is for personal use, jam use or for sale. It also depends on how often you change guitars.

Concentric knobs save space but they violate the rules above. Plus, you have to be delicate to adjust one without accidently twisting the other.

For real estate considerations, a Marshall-style illuminated switch saves one space in the line. You can also work a choke/resistor or fixed/cathode bias from an on-off-on DPDT standby switch with standby in the middle position.

FWIW, Skip

[RJ Guitars]

Heisthl,

How is the minimal knob Dumble going? This is a really cool idea... one I am hoping to follow you on. For the first time, I played through a D-Clone a couple weeks back. It was a great amp and inspired me to move forward with my own clone... hopefully we'll see that before the new year.

As I played through the clone I realized I had a lot of tone options that were overwhelming to me at the time... For the most part I didn't mess with most of the knobs once I had some good sound. I am greatly convinced that you can get a very Dumblish sound with fewer knobs.

Hope you are still going on this... May I inspire you and learn again from your great posts?

Thanks,

RJ

[heisthl]

Well so far I built a Telecaster amp with a deluxe 5E3 first stage and tone circuit into the 220/500pf dumble CL2 (no LFB) and Dumble PI and after a few capacitor tweaks it sounds amazing. No OD on this one but the PAB of a lifted "Tone" control gives it a nice fat semi-overdrive sound. I am planning on doing a minimal OD amp with a "tone" and single overdrive control for a 4 knob amp (volume, tone, OD and master) with a fixed presence value. The single OD control will probably be a stacked 100K pot with trimmers(level wired the reverse of drive) so that the sound level is consistant throughout the drive pot's travel.

[hairyandy]

No preamp volume is a concept I hadn't even considered and it really appeals to me. The use of a "tone" instead of bass and treble eliminates the need for a bright cap and if designed correctly also allows you to preset the mids.

Just an idea.

Check out the Lab Notebook at Jack Orman's Muzique.com website:

http://www.muzique.com/lab/main.htm

He's got some great info there, especially on one knob tone controls that might adapt well to the Dumble circuit...

Andy

[Tybone]

I have been going the other way as I NEED to wrap my head around my amp. It is a two rock opal and has 5 toggle switches, two tone stacks and 3 freakin master volumes. Including reversing the speaker polarity it took 18 months or so before I could feel comfortable that I know the amp. It responds differently to each and every guitar and (this is where it gets messed up) can do HRM and non HRM with PAB just by flicking a few switches. One is gainyer and one is smoother and they both don't suit all guitars.

Plus I love the tone contour switches. On this amp the deep switch does something. This switch is the fender tone switch basically.

I am proud that I can dial this thing with any guitar. True you can dial in some skanky tones. But you can also go places you didn't know about. I love that flexibility. It is counter to the one trick ponyism that you can sometimes run into.

BUT if I could get a dumble tone out of a 5E3 type package you may put me down for one!

[BobW]

My .02 cents. FWIW,

I don't consider myself a knob guy either, but the Clean, OD, and M Vols are a must, since I switch between a strat, an open tuned LP copy w/P-90s, to an open tuned musicmaster w/one humbucker.
The PAB is also a must. I use it for solos, and sometimes leave in on an entire tune. However I believe I could live w/o a 3 tone stack (B, M, T) and have just a 2 tone stack (B, T).
I set the rock /jazz, deep and bright switches then leave em alone.

In order to get that sonny landreth type of tone from one tune to another, the clean and OD Vols get adjusted depending on what guitar is used. Although I don't usually use a pick, that may add to the additional knob adjusting.

[scattitude]

IMHO, having 3 tone controls is important. Being able to boost or cut the mids allows you to 'clean' up the frequency response and tone of the guitar, which, depending on the guitar's tone and pickups, may have more mids already present. I've found that with some lower-output single-coils, a mid-boost (either on a pot or switch) can fatten up the tone; whereas with some humbuckers, you need to reduce or 'scoop' the mids so that the guitar will be clearer sounding from lows to highs. A single tone-control might be 'easier' to use, but would have to be designed with a fixed frequency response and might only suit certain guitars well.

[Structo]

Yes, you have to be able to tweak the tone for different room acoustics.
The amp may sound fine in your shop when experimenting with hard wired values, but get it into a room that sucks the highs out of it and you will have a muddy sounding amp.

This is what I did to my D'Lite to be able to see the knobs better.

[IMG:640:387]http://i23.photobucket.com/albums/b392/ ... mknobs.jpg[/img]

[muchxs]

The amp may sound fine in your shop when experimenting with hard wired values, but get it into a room that sucks the highs out of it and you will have a muddy sounding amp.

The room itself changes. An empty hall during soundcheck has an entirely different acoustic than one full of people later during the show.

Having said that too many knobs are just window dressing. I'm building an amp as a Christmas present for my nephew... there are NO knobs on it, just an on/off switch and an input. Volume wide open all the time, baby! The guitar that goes with is has no knobs, just a hot humbucker wired straight to the 1/4" jack.

Honestly I built the amp to torment my ex-sister-in-law.

[heisthl]

It took a lot of new thinking and tweaking but here it is, the minimum knob non-HRM (actually it could have less with no presence knob). The OD control is a stacked pot (one CW and one CCW) with some tail resistors for the extremes. The preamp volume is fixed and controlled by the rotary mode switch which also does some other things to give you choices of the naturally distorted Tweed sound or a halfway variation or regular clean, the OD is footswitch enable only but changes character as the mode switch changes. The od control at 0 matches the non OD volume and at 9 o'clock has just the right volume bump for soloing. As you turn the knob it increases the drive but decreases the level with a slight increase in overall OD volume.

[gregarious]

As always heisthl, the goods are in a very smart looking package!

Would love to hear the results of your distillation efforts and have a peek under the hood, time & inclination willing.

Anyway, looks killer!

[heisthl]

I got one of those "TuffBox" (size DD) and lined it with insulboard - total weight of amp and case 47.5 pounds! Airline checked baggage weight. But better yet looking at the guidelines for Musical Instrument carry ons - this amp can be carried on - it's 16.75 x 16 x 7.5 @ 35 pounds.