Using original TS9 footswitch as a Boost??????

[darron]

it wouldn't be hard at all to do a gain boost. just take one of the resistors from the feedback loop of the opamp and replace it with two resistors in series that add up to the value (or close) of the original resistor. then have the SPST momentary switch short between two legs of one of those resistors, that way making only ONE of the resistors come into effect and you'll have a lesser value.

i've never done that before, but it should be good?

my argument still stands that you accidentally hit it really easily.

[drewl]

I don't have a pic of mine, but after building a Fulldrive clone, the "boost" didn't boost enough for a very picky friend.
What i did is wire up the boost switch to increase the value of the 1k feedback resistor on the 2nd stage of the op amp.
I think I settled on a 22k which REALLY kicks the output of this thing up alot!
Try it, it's easy and sounds great!

[Dragonfly]

thanks for the diagrams but, I don't know if I'm just interpreting them wrong or what but, that looks like just a volume boost. What im looking for is a gain boost. I'd like to have the original drive control on the pedal at about 9 or 10 o'clock for a light rythm drive tone then kick on the old original on/off switch and have the gain FULL OUT for leads. I believe i've seen this before but I can;t seem to find it on the web. I should have bookmarked it when i saw it the first time.

You "do" realize that just because the second diagram says "volume" that you can do it for "gain" (or "rate", "depth", etc..)...it's just a easy way to switch between two different pots.

I built a EA tremolo with 3 footswitches... 1 for "on/off", one to toggle between two different "rate" knobs, and one to toggle between two different "depth" knobs. At the touch of a footswitch I could have :

fast rate / low depth
slow rate / low depth
fast rate / high depth
slow rate / high depth

or anywhere in between that I chose to set the knobs.

I would suggest 1M resistors to ground before and after the switch to make sure that there's no popping however...thats not shown on the diagram.

if you want to go between 2 "gain" settings, it will work, and is easy to implement.

[darron]

I don't have a pic of mine, but after building a Fulldrive clone, the "boost" didn't boost enough for a very picky friend.
What i did is wire up the boost switch to increase the value of the 1k feedback resistor on the 2nd stage of the op amp.
I think I settled on a 22k which REALLY kicks the output of this thing up alot!
Try it, it's easy and sounds great!

taking the other feedback resistor and increasing it is probably a better idea than what i said about lowering the other. i forgot we were only talking about a 1k resistor.

[drewl]

It really kicks up the gain AND volume but doesn't mess with the tone too much.
Actually what I did was wire up a 22k pot that switches in series with the 1k, then you can dial in the boost from a little to a whole lot.
Anything more than that and it started turning to mush, that's how I came up with the 22k.

[Melanhead]

By the way melanhead.... if you could come up with something that would be AWESOME as well. I modded a DS-1 and SD-1 according to your mods that I found here and i gotta say that THEY BEAT ALL THE OTHER MODS I'VE FOUND ON THE WEB!!!!!! 

Gee, thanks! ...

I looked at it last night but was too lazy to do it and just let it be. Here's what I thought would work but I can't really diagram it or give you part values as the Ibanez boards don't label them ... You'd have to reinstall both of the FET switches you removed by doing the Keeley mod. They flip flop so one is open when the other is closed. One of them is connected to the output of the first buffer, this was your bypass signal before doing the true bypass mod. What could be done is that you have 2 gain controls, the output of each ( pad 2 I think ) one connected to each FET switch. You'd have to make sure they were isolated from the rest of the circuit though as you don't want them to act the way they did before. A bit of a pain in the butt and that's why I didn't bother. if you look at the TS9 schematic I'm sure you could figure it out. I'm not sure what Keeley does,( i thought he switch volume pots ) but it could be this way or using a switch similar to the new Maxxon pedals, which I think are latching. But then again, who knows  ... There are many ways to skin a cat, I find it more convenient to use a separate boost, with a gain and volume control

[Melanhead]

It really kicks up the gain AND volume but doesn't mess with the tone too much.
Actually what I did was wire up a 22k pot that switches in series with the 1k, then you can dial in the boost from a little to a whole lot.
Anything more than that and it started turning to mush, that's how I came up with the 22k.

another interesting way to do it ...

[Barcode80]

i had the same problem with the fulldrive clone i built, because i do NOT understand how anyone hears a significant boost with the configuration the fulldrive has. Instead, i hard wired it wide open, and used the pot as a volume pot for an lpb2 wired before the fulldrive. that way, i got a REAL front end gain boost when i hit that switch.

[drewl]

The Fulldrive boost seems to work a little better with clean amps, it has more headroom to boost.
One guy thought it was a significant boost stock, but my critical friend likes knobs to make a big difference.
I've built amps for him and all the tone controls have to do ALOT.
Anyway, think I'm gonna build another one with this set up.