JoeAArthur

I'd use a DPDT toggle... using the other pole to ground the input to the amp I ain't using. An open input to an amp is only an invitation to create additional noise that you probably don't need. Edit dang it. A DPDT with a center off position. Either amp or both.

After more than about 50 cents for a cap, I'll do without a tone control!! Hype, hype, hype... and oh... did I mention hype?

On any string, no matter how far out the intonation is, the 12th fret natural harmonic will always be in perfect tune with the open string. Compare the harmonic with the fretted 12th fret note. Adjust intonation accordingly. Edit for extra thought: Do you have a floating tremolo?

I've read this several times. For the life of me I can't come up with any reason (other than you might not like the sound) why you can't have 3 reds in the same guitar. Certainly no reason why having 3 reds in and of itself would cause you to have more hum. Do you have this hum in all pickup positions? If you do, then I would suspect something like bad grounding - like maybe the string ground is no longer connected. After all, one lace sensor ain't gonna know it's got two brothers when only one is selected. To answer your question about reducing output using resistors, yeah, you can. But the resistor would probably have to be a real high value to have any real reduction effect - like a 250K if your're using 250K pots would only reduce the output by 6db - like the difference between the #1 and #2 input jacks of a Fender amp. Trying to come up with an appropriate value would be a lot of hit and miss experimentation, and might even increase your noise. You could connect a trimmer pot internally to those two pickups in a volume control configuration. But I still can't see why having 3 reds causes more hum.

That's funny I foolishly thought he was talking about physical placement of the controls on the body!!

I'm not sure if it is "wrong", it's just not the way I would wire volume and tone pots. It's just different and I was wanting to make sure you intended to wire them that way. I would have connected the output of the switches to the left hand terminal of the volume pot and not the center terminal. I would have taken the output to the jack from the center terminal of the volume control and not the left hand terminal of the tone pot.

Could you check the volume and tone wiring? I've never seen this particular way of doing it.

Crate's "shape" control is essentially the same implementation as Marshall's "contour" control on their ValveState amps. Here is a PDF of the schematic for the Crate VC508 which uses this same implementation as it's "tone" control so you can see how it's wired: http://www.stlouismusic.com/downloads/divi...08/25101H2_.PDF It wouldn't be a good choice for a guitar tone control unless you also install a preamp - the insertion loss of of this circuit would result in a loss of volume.

Can I assume you have three pickups? If so, then the wiring would be a strat with a master tone instead of the dual switched tone pots.

Really. Maybe this is just a "I have this many spare parts" kinda post.

IMHO - I'd find the best place where the pole pieces align with the strings. Pickup positioning by nodes has been discussed all over the net - but most ignore that when you fret a note all of the nodes change position - not to mention changes in node position as a result of intonation across the strings.

Ok... I'll add my $0.02 to the original question. If you have a 60s era Vibrolux Reverb with a master volume control - it ain't stock. To me, that's enough reason to remove it. Fender only added master volume controls in the early-mid 70s and after 1968, all of those amps would have been silverface (not that it is a bad thing, just a fact). However, Fender did revert back to blackface cosmetics sometime in the early 80's. I think the Vibrolux did get a "pull-boost" switch sometime after 1976-77... but I don't have anything that proves it, but if you have a blackface Vibrolux reverb with a "stock" master volume control, chances are pretty good that it is one of the early 80 models, and not a 60s. Why remove the master volume on silverface amps. Several reasons. First, the master volume control as installed is a "loudness" design - there is a "bright switch" style cap that is connected to a tap on the master volume pot. This cap will boost treble at a low enough control setting... and cut treble when the control is above the tap point. Cutting this cap out will restore a lot of the "shimmer" found in the earlier non-master-volume amps. The master volumes with the pull boost amps introduced additional treble cutting networks. Some of these are not obvious... something like a resistor and capacitor in series IIRC. Removing these networks along with the master volume also restores a lot of presence to the amp. oops... ran out of change.

true... but most effects loops are line level instead of stompbox level. What kind of amp is this?

lmao! i liked those little amps back in the day LOL! well i do like tube tone, but i guess i am not what you would consider a purist. i like the tone that i am getting by using both a ss/hybred amp and a pure tube amp togather and would like to have the common features between the 2. so i guess the mod is possible, but not a recomendation for the tube purist ? has anyone here had the chance to use a marshall vs100(8100)? if you have ? you have to admit the amp does have good tonal quality and does have more warmth than a ss amp. grant it, it is no jcm! but does have a certain degree of warmth, not found in ss amplification. Ok... I'll bite. All you are doing with your modification is building a fuzz stompbox into an amp. Why not just use a fuzz stompbox in front of the amp? It'll be a heck of a lot easier... especially considering the errors in your hand-drawn schematic (e.g. where is the B+ coming from for the first tube stage?)

The Gibson P-90 equiped guitars I have actually torn apart have all had 500K with 0.022 tone caps (one was an SG style, the other two were LP style). It's not really single-coil vs humbucking that makes the decision, and both Gibson and Fender have used both values - Fender even used 1 meg controls in Tele's for a while in the 70s - for both single coil and humbucker. For what it's worth, I base the choice on the impedance of the pickups... humbuckers normally have a higher impedance than single coils. However IIRC, P-90s have a coil resistance up around 8.3 - 9.6K range making them closer impedance wise to humbuckers than most single coils.

I see. Some of the toggle style pickup selector switches do have 4 terminals with the middle two usually soldered together. So your 3 terminals and a ground only has a single terminal replacing the two in the middle. Not a problem. You can ground the toggle switch even if it doesn't show a connection on the schematic. Probably not necessary if the switch has a plastic cap, but if it has a metal tip I'd ground it.

500K.

Open up the back plate and locate your volume controls. Of the three lugs, one will be attached to a ground, probably the back of the pot. Leave this terminal alone. Unsolder, reverse the connections of the other two lugs on each pot, then resolder. Presto - independent volume controls. Some gibsons (among others) come wired this way - it's the same as the volume control wiring of a Jazz Bass.

The schematic is a little fishy itself. The way it's drawn, the input to the phase inverter is coming off the B+ line? Chances are good that the 500pf to the right of the second tube is really the input cap to the phase inverter. Some schematics have intentional errors, others may be accidential.

Did you try the BlueGuitar site search? I got this... look under the files that start with smokey. http://www.blueguitar.org/new/schem/_ss/?C=N;O=D

In that schem... the values of C2 and C3 are flipped. It looks like you might have copied them from Duncan's TCS - at least at one time he had them backwards. The current version has them corrected. You might want to download it to help experimentation with values. The tone control network is going to have some insertion loss. You might be able to make it up with the preamp's gain. Since you are planning on using it as a pedal, there is the option of sticking a volume control after the treble control output... and then adding another gain stage for recovery and buffering the output to the amp.

You could replace C2 with the tone network. Since the values for the tone network aren't given, you might have to scale them from either the Fender / Marshall / et al values. The output impedance from the preamp appears to be much lower than what you would have in an amp.

You should never have to use a separate soldering flux with electronic circuitry.

Yes. You might pick up some additional hum as the electromagnetic speaker winding acts more as a choke than a straight resistor. You could use a choke instead of a resistor if the hum becomes a problem.

Since you already have a reverb unit, you will probably want to build the circuit around it. Go to this site: http://www.accutronicsreverb.com/ Input impedance is more important than output impedance, as the drive level to the reverb will have the most effect on how it will sound. Look under the "applications" section and try to determine the input impedance of your unit. The site also has various schematics for both drive and recovery sides of the reverb. Most shutting off thingies ground the output of the reverb, or the output of the reverb control. Reverb is not a "pass through" type of effect. A portion of the raw signal is mixed in with the delayed output of the reverb. By grounding the reverb output, then you are left with the raw signal. Hope this helps!!