Mr Smoothie

[seanm]

This is what I think the Fat Boost should have been. It is Jack Orman's Minibooster with a real gain stage thanks to T. Escobedo's Utility Boost. This will do a clean boost to a mild overdrive depending on the gain setting.

Rather than a useless tone control, it has a simple low pass filter. Ok, maybe to most people that is not a move forward But I find it really tames the overdrive. Remember, this is supposed to be smooooth.

More info on my web site: http://seanm.ca/stomp/ and follow the link.

[j0shua]

Very interesting circuit

Well done Sean

[seanm]

Thanks. On my website I mention that Q1 has to be a J201. When I tried multiple 2N5458s, they gave less than unity gain. i.e. They attenuated the signal.

Is the biasing not correct for a 2N5458?

[Alpha579]

looks cool!

what drain voltage did you get with the 2n5458?

[seanm]

looks cool!

what drain voltage did you get with the 2n5458?

This is off the top of my head and is probably wrong, but 1.75V rings a bell.

[j0shua]

looks cool!

what drain voltage did you get with the 2n5458?

This is off the top of my head and is probably wrong, but 1.75V rings a bell.

Hmmmm try the 2n5457 or 2n5458 FET ?
the J210 are little better than 2N5457 or 58 try NTE459 N-Channel Silicon JFET Transistor AF Amplifier/Chopper/Switch

[Mark Hammer]

Well that's what a lot of people seem to forget.  If your intention is to add harmonic content, it is always smart to shape the spectral content of what you're going to add harmonics to, so that desirable harmonics are showcased moreso than undesirable ones.  Incidentally, don't be shy about using a 2-pole filter.  A relatively standard 3-position on-off-on DPDT toggle can yield two settings of lowpass plus a "filter-lift" setting.

[Alpha579]

hmm, 1.75 is not good...you could try using a trimpot for the drain resitor instead of fixed, so you can use different j-fets...

[davebungo]

O.T. Do you mind me asking what you used to draw the circuit and how you inserted it in your post - it looks very similar in style to the AMZ stuff (the graphics and fonts that is).

[j0shua]

O.T. Do you mind me asking what you used to draw the circuit and how you inserted it in your post - it looks very similar in style to the AMZ stuff (the graphics and fonts that is).

Are many Software to do that like :

circuit maker, expressPCB, EAGLE, Protel, etc.....

Circuit Maker have Student Free version

** have some errors in netlist ( Some IC's do not appears )

[seanm]

O.T. Do you mind me asking what you used to draw the circuit and how you inserted it in your post - it looks very similar in style to the AMZ stuff (the graphics and fonts that is).

I used xpaint to draw the schematic and gimp to make it transparent so it blends into the background. Very very low tech :oops:

I host the pages on my website and then use img tags to insert it in the post.

I took the basic graphics from the bazz fuss schematic at runoffgroove.com. They are a good size and the resistors are double width so that a fill fills the whole resistor in one go. I was going to use the minibooster schematic at AMZ but the graphics are too large.

The font is lucidatypewriter 12, a very basic fixed width font. The Mr Smoothie is MS comic sans.

[aron]

Nice circuit. I agree about the trimmer on the drain, but it should sound nice.