[sdiy] comp/limiter/distortion [was: Possibly OT, advice needed...]

[Seb Francis]

Here's a sneak preview of something I've been working on for the past 
while ...
http://burnit.co.uk/sdiy/preview/

BOX-O-TRIX: Modular Compressor/Limiter/Distortion/Gate Unit
"Squeeze Box" (x2): VCA type compressor/limiter based around a THAT4301.
"Dirt Box": Diodes & Opamp based clipper with fully variable asymmetry 
and clip hardness
"Fat" (x2): 3 stage JFET based distortion
"Tube 4069" (x2): Between 1 and 3 stages of MOSFET 'tube sound' distortion
"Gate"  (x2): Noise gate or External trigger (audio or MIDI) 'chopper' gate.

It's way over the top for 1 guitar .. I designed it to fulfil all the 
compression/distortion/gating needs of my whole studio (lots of analog 
drums and synths)

The sub-circuits have all been breadboarded, tweaked and finished, the 
panel layout is done.  I'm just doing the PCB layout now, so won't be 
too long until it's finished (at which point I will put full details up 
on my website).

If anyone's interested, I'd be happy to sell PCBs at cost (would make it 
cheaper for me anyway - right now I'm just planning to get 1 PCB made).

Seb



Dave Kendall wrote:
> A comp/limiter sounds like a good idea. It'd be good to get it all into a 1U
> 19" rack. I guess then the thing would be to have a switch on the floor
> activating a CMOS or relay switch in the rack unit itself. This could switch
> between chorus, and comp/lim into Distortion. Volume pedal maybe driving a
> VCA in the rack to keep signal cable length down? Using the volume pot on
> the Rhodes would affect the drive of the compressor and/or distortion stage,
> which might or might not be a good thing.
> Lots to think about.....
>  
>   
>> that reminds me of the big glitch with using keyboards through distortion--
>> depending on what you're using, chords can sounds TERRIBLE. with guitars
>> you've got very rich harmonics, and the pickups also get the sympathetic
>> vibrations from the strings you're not playing, and that's on top of the
>> fact that a signal from a magnetic pickup is going to be pretty different
>> than one from some opamps and a keyboard or synth...
>>     
>
> I always thought that the Rhodes was the bastard love child of a Piano and
> an Electric guitar anyway - certainly all those pickup coils don't like
> being anywhere near the underside of a K2000 - mega hum!
> If you stick to intervals like 4ths and 5ths and octaves, it tends to work.
> There is definitely some sort of sympathetic resonance thing going on, and
> the high gains probably exacerbate this.
>
> Rhodes + distortion should definitely be a Jazz-chord free zone :-)
>
> Dave
>
>
>  on 8/4/06 17:10, NATE! at timexheater at comcast.net wrote:
>
>   
>>> Also, try a compressor/limiter before the distortion unit so that
>>> single notes can drive it almost as hard as chords do. That way,
>>> single notes will produce overdrive but chords won't turn to total
>>> mush. (Not that there's anything wrong with that. ;-)
>>>       
>
>   
>> the perfect example of this would have to be running a casio through
>> distortion... for single notes it's great, but chords are just nasty.
>> luckily most analog synths aren't polyphonic :)  and organs are rich enough
>> to not really sound like ass [unless you get into beat frequencies lol]... i
>> don't know how a rhodes would sound though.
>>
>> - nate
>>
>>     
>
>
>
>