DiSCO - Dirty compressor and overdrive

[Cozybuilder]

I've had a chance to play with it a bit, you did a great job with this Sam! Now to paint a box for it (stripes?)

It should look a little better than this once boxed:

[samhay]

Can't decide wether to paint the box pink (distortion) or neon lime (compressor). Decisions decisions

I've had a chance to play with it a bit, you did a great job with this Sam! Now to paint a box for it (stripes?)

Well pink and green stripes might look very cool, but you probably won't have room for many stripes if you are planning on building it in a matchbox.
Alternatively, if you mix pink and green, you get brown...

Glad you like it. I see we went to the same school of spaghetti monster breadboarding too.

[samhay]

I added Big muff's tone control to this but ended up omitting it, so I have to say you're right about no need for tone control.
Right now I'm working on a PCB for this circuit and will post it as soon as possible. It deffinitly takes a place on my pedalboard.
Thank you Sam.

Thanks for trying out some tone controls with it - I am generally quite nervous designing dirt boxes that don't have adjustable EQ, so it's great to see that there seems to be some agreement here.

A PCB would be great - doesn't look like a trivial build on vero.
Feel free to post it here if you feel like sharing.

[samhay]

I made the changes to my vero layout.

I had to compromise alittle to keep the size 1590B friendly,
so I didn't include the millenium switching and kept the comp LED as the 1.2 version.

cheers / Freppo

Nice job Freppo. I started laying this out on vero last week and quickly realised that it isn't a particularly easy circuit to route.
The 1.2 switching seems like a good compromise, and I would imagine most people will be happy to use 3PDTs anyway.

[Freppo]

I built up the vero layout today.
It works fine, except the symmetry switch.

With the SW4 / SW5 not connected it turns out a massive square-wave fuzz and has no response to any of the controls.
Correct me if i'm wrong, but don't you still need a 10K resistor from the inverting input to the output of IC2A?
I guess now it's turning into a comparator without it when the input/output isn't jumpered by the switch.

cheers / Freppo

[samhay]

> Correct me if i'm wrong, but don't you still need a 10K resistor from the inverting input to the output of IC2A?

Sorry - that's correct. It looks like I forgot to add the 10k to the schematic (now updated).
It looks like you have enough room in your layout to add the resistor if you stand it up.

[Cozybuilder]

Wow, that 10K in the feedback loop makes a huge difference! Now the two switch positions are a lot more compatible. I thought I had miswired and was about to start troubleshooting, glad I looked at the thread first.

[Freppo]

Okidoki. I updated the layout and added the final version to the vero-archives in my blog
http://parasitstudio.weebly.com/stripboard-layouts/disco-dirty-compressor-and-overdrive

I had to make in one column wider, but it will still fit a 1590B if you put the layout sideways.
If it has more then 4 knobs I'll always go for a larger box anyway, but that's just my personal preference.

I will post some picture when/if I get around to boxing it.
Thanks again for sharing this project!

cheers / Freppo

[samhay]

No problem Freppo, and sorry about the schematic %^&*-up. I hope that the rest of the builds go without incident.

Side note. Freppo - I see you also did a layout for the 'Cherub'. If you built it, what do you think?

[Freppo]

I enjoyed your Cherub Chorus alot. It sounds great.
Just another project that I never gotten around to boxing. 

The only negative thing about the cherub (aswell as the dimension p) is that I find them are a bit noisy (hissy)
I think some hi end pre-emphasis at the front end and some roll-off at the end would reduce most of the hiss.
The pre-emphasis I have in both the Parasite Phaser and the Green Currant Tremolo helps to reduce the noise alot.
Just a thought, maybe worth experimenting with

[samhay]

Glad you liked the chorus - I have a Dimension P too, but can't remember how to drive it as I built one with too many options.
I may have got lucky with my build of the Cherub, but it is pretty quiet for a little box with a PT2399, a LFO, and a dodgy layout. My recording interface is playing nice this evening, so I dug it out and recorded a new sample: https://dl.dropboxusercontent.com/u/11996927/Cherub2.mp3
Any chance the hiss you hear is coming from the PT2399 (some are worse than others) - does it get louder with the mix knob?

In any case, it would only cost a couple or resistors and caps to add some pre- and de-emphasis, which is a good idea, so will add it to the list for a revision at some stage.

p.s. no shame in not having boxed it yet. I have mine in a blank box, and it doesn't look like I will be adding labels any time soon.

[DougH]

Sounds great!

[samhay]

Thanks Doug

[Kipper4]

Good work Sam and Freppo.
Two more to add to the list. It really does sound great too.
Rich

[DougH]

Yeah, you really did a great job capturing the compression and the touch-sensitive power stage distortion here.

[samhay]

Thanks - it was one of those ideas that worked better than I thought it would. Nice to have something that is a just a little different too.

[Cozybuilder]

Finally finished- thanks for one of my favorite pedals Sam! I really like this at the beginning of the chain- just a little OD sounds great with the other pedals, the compression really smoothes out the overall sound. Versatile.

 

[samhay]

Nicely done Russ.
I see why you went for 2 LEDs now - very period correct.

[samhay]

Just noticed another error in the ver 1.3 schematic, which I have now fixed.
SW2A (Symmetry switch) should only be shorting D3. As it was drawn, it was also taking D1 out of circuit when the switch was open - not the intendend function, so I have moved D1.

Freppo, in your layout, you will need to shift the anode of D7 (your labelling) down to the op-amp output - it will fit if you move it left 2 rows.
Russ, not sure how you wired your switch, but it will probably work better if you do it as now drawn.

Sorry guys.

[Cozybuilder]

This was the schematic I used, D1 is always in the circuit paralleling D2, D3 gets shorted. In your post above, the difference is that D1 will parallel the pair D2 and D3, or only D2. I can do that by switching the 2 leads to SW1A (D1 to SW1A center, and D3 to SW1A #3.) Right?