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DIY Stompboxes => Building your own stompbox => Topic started by: Somicide on August 01, 2004, 06:48:26 AM

Title: Orman is the MAN
Post by: Somicide on August 01, 2004, 06:48:26 AM
Out of curiousity, I built the "Muffer" from his page, which it explains is a BMP stage.  I built it on a PCB the size of a quarter, but square.  Nice dirty sound, real loud, just lacking in highs.  Good fun though.  Peace N Love,

Jeff
Title: Orman is the MAN
Post by: Elektrojänis on August 01, 2004, 07:18:14 AM
The lack of high frequency content might be because of lowish input impedance. You could probably get more highs by placing a simple fet booster before it. It would probably not make the circuit too much bigger. It wouldn't be as simple then though.

Edit: Driving it with a fet booster might make it harsh though as the lowish input impedance (that is loading the pickups) might be smoothing the sound (like in FF and others).
Title: Orman is the MAN
Post by: brett on August 02, 2004, 02:00:05 AM
Hi.  You can lift the input impedance a fraction by putting a resistor in series with the input (as per boutique FF), or lower the emitter resistor to, say, 100 ohms.  That'll boost gain a fair bit, which you might not want.

good luck
Title: Orman is the MAN
Post by: Elektrojänis on August 02, 2004, 03:50:56 AM
And ofcourse the common tweaks of changing the input and/or output caps to smaller values will make a brighter sound. Smaller input cap might make the drive level a bit lower though.
Title: gain o matic
Post by: Somicide on August 02, 2004, 03:57:24 AM
This thing has gain to spare, so i don't think a loss would be too bad.  How much would it go down if I put in say a .1 uF?  Peace n Love,

Jeff
Title: Orman is the MAN
Post by: Elektrojänis on August 02, 2004, 05:04:13 AM
I'd try 0.1µf on the input side for starters. It might not cut bass that much though so you might need to go even smaller values.  BTW. It will change the tone of the distortion too.

BTW. Jack Orman is the man. He's been doing this stuff for a very long time.
Title: Orman is the MAN
Post by: mikeb on August 02, 2004, 05:40:42 AM
Hopefully Jack will come out of 'retirement' soon!

Mike
Title: Re: gain o matic
Post by: David on August 02, 2004, 09:54:18 AM
Quote from: SomicideThis thing has gain to spare, so i don't think a loss would be too bad.  How much would it go down if I put in say a .1 uF?  Peace n Love,

Jeff

Jeff:

What transistor did you use?  I built one with a socket so I could experiment.  When I put a 5089 in there, I got a screaming, gain-laden monster!  Now that you mention it, though, it does seem a little "bassy".
Title: Orman is the MAN
Post by: Gilles C on August 02, 2004, 10:41:57 AM
It's a fact that it's not ear piercing like some other Treble Boosters.

I would say it's just a helper more than a booster for the highs.

I used it a few times just to take some bass out of my guitar that is quite bassy, and it was ok for me. But just because I don't really like Treble boosters...  :oops:

But a little more treble would be nice...  :wink:

The one I built:

(http://www.finitesite.com/gtechblues/photos/MuffMast2.jpg)

Useful in an effect loop.

Gilles
Title: Orman is the MAN
Post by: Elektrojänis on August 02, 2004, 03:25:14 PM
Muffer a treble booster?
Title: Orman is the MAN
Post by: Ben N on August 02, 2004, 06:41:59 PM
That would be the Muff-master, which, IIRC, is on the AMZ cd.
Title: Orman is the MAN
Post by: Gilles C on August 03, 2004, 12:30:54 AM
It is also on the site

http://www.muzique.com/schem/projects.htm

But I just realised I was thinking of a different circuit than the one in the original post...

This is what I built.

(http://www.muzique.com/schem/muff3.gif)

It can help modify the real Muffer.
Title: yup
Post by: Somicide on August 03, 2004, 03:25:06 AM
David,
I used a 5089, love em, and I've got like 50 lying around sooo...  good choice!  I think I will lower the input cap.  Another though, could all this be done with a 2n7000 as well?  I ask because I have a few of those lying around too.  Peace n Love
Title: Orman is the MAN
Post by: Elektrojänis on August 03, 2004, 03:46:19 AM
Oh... Don't forget you can try to tweak C3 too.

Also putting somethin like 1µF - 4.7µF cap parallel with the R4 might boost treble a bit.