Rat (Rodent ) tweaks

[dosmun]

I finished my Rodent yesteday and it sound good.  The only problem I have with it is the Dist control.  It kicks in very early and I can't get any of the milder sounds out of it.  I know in Jacks mods you can use it as clean boost.  Exactly what is the mod that does that?  I have is CD but it doesn't really say specifically what each mod does.

[Mark Hammer]

Part of that may well be the taper on your gain pot.  Different tapers can end up compacting all the resistance changes of interest to a given user into a very narrow arc of rotation.  Switching to a different pot or altering the pot taper with parallel resistors (see The Secret Life of Pots over at www.geofex.com) can often fix this.

One way to completely eliminate deliberate clipping in a Rat is simply to lift the connection between the diodes and ground.  Another way to yield subtler coloration is to wire up a 10k pot as a variable resistor between the diodes and the point where they tie to the input side of the tone control.  At max resistance they will clip VERY softly, and for lower gain levels, not at all.

[dosmun]

I tried the 10k pot after the clipping diodes and it was OK,  I then tried a couple of larger value pots and a 250K was very cool.  At max resistance it rolls off a ton of high end so you end up maxing the tone control on the Pedal.  It almost gets into that smooth TS territory but without the mid hump.   Is there a way to get a little more high end out of the tone control when using the extra pot?  Or maybe rolling off the low end might be a little better.

I really like your suggestion for that pot though.  It looks like I might be adding another hole in the case.

[Mark Abbott]

Did you try Jack Orman's mods?

I implemented these mods into my Rat pedal and it sounded much better for them.

Yours Sincerely

Mark Abbott.

[dosmun]

Which of Jacks mods boost the minimum gain so it can be used as a clean boost?  His mod sheet doesn't really explain what mod does what.

I plan on trying a few of his mods.  Probably one at a time.  I am a little leary because the sound samples he has don't sound nearly as good as my stock Rat.

[Mark Abbott]

The mods that Jack suggested that I like, was replacing one of the Si diode with two Ge diode in series. This (to my ears) sounds cool, it sounds like a mix of Ge and Si diodes with the Ge being more prominent.

If you are after a louder clean tone try his alternative mod where instead of replacing one of the Si diodes you put a Ge diode in series with one of the Si diodes.

I think to increase the "clean" gain you will have to do something like the Tube Screamer mods where you have two Si diodes in series on one or both legs of the clipping diodes.

You could also try the Turbo Rat thing where you use red LEDs instead of regular Si diodes. One LED and one Si diode might be what you want.

I hope this helps.

Yours sincerely

Mark Abbott

P.S. Try experimenting with the tone control cap too, Jack recommended changing this to 0.0047uF, and later he liked 0.01uF.

[dosmun]

I have been having a lot of fun tweaking the rat.  I tried the LED as the clipping diodes.  I am thining of having a switch to change between these and another combo.  Tonight I am going to try adding some Tone contols.  So far the Rat clone has been a blast to work with I have already added an extra 100k pot to soften the clipping,

Thanks again guys

[Mark Abbott]

You might try asking around, I think one of the Fulltone pedals is a RAT with guitar amp like tone controls, I've never seen or heard one so I can't add anything further about it.

I think the AMZ Overdrive Pro also reflects this kind of approach too.

Yours Sincerely

Mark Abbott.

[dosmun]

I am willing to try about anything with this Rat clone.  It sounds great already but I have a 80's small box Rat and a Vintage Reissue already so I am looking to tweak the clone into something different.  So far it is going great I am getting a lot of different and cool sounds out of it.

It may not end  up in a box for awhile until I figure out how many controls this beast will have. :roll:   It is getting bigger everyday :twisted: