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I'm happy to report the Cosmo runs great off of 15V without any mods. Much more headroom available for higher level signals.

Hi. Thanks for your response.

Since the new unit will be built from scratch with the new voltages in mind I'd rather figure out how to run it off 15V and not attenuate the input signal too much. The input stage is very similar to the Jack Oram MOSFET booster. There's are mods section on the booster page that states it can run safely up to 18V as is. If the 9V Zener is ok with the higher voltage I don't see it being a problem for the AC127 and BC109.

Any thoughts on this?

I'm going to test 15V on my Thunderpuss and then on my Cosmo pedal. I'll report back.

Thanks

Hi

I love the sound and functionality of the Cosmopolitan and would like to modify the circuit to use with line level sources. Ideally I'd make 2 in a box to use in stereo.

First I'd like to raise the operating voltage to 15V and then adjust the input and output impedance if necessary. I assume I need to change the 9v zeners to 15v? I would also change the input resistors to better deal with line level impedance?

Here's the schematic link. Any help is greatly appreciated. Thanks!

http://www.madbeanpedals.com/projects/Cosmopolitan/docs/Cosmopolitan.pdf

Thanks. Yes it was a weird problem. I ended up removing the switch and the LED's and hardwired it to diode clipping and now it works fine. I think I will just leave it as is. I must have had a short somewhere.

It Sounds great! I'd like to try the LED clipping at some point but for now I am happy with it and the sweep and filter controls add some nice variation to the sound.

Thanks for everyone's help!

Charles

Ok so getting back to this one after finishing the awesome Dirtbag!

I have removed the LED's and now the diode clipping works and the center switch position gives me a slightly overdriven sound as I would expect. But when the LED's are in I get nothing in either clipping position and light fizzy sound in the center position. I have checked the polarity of the LED's and that looks ok. They are 5mm diffused red ones.

Any help would be appreciated!

Thanks, Charles

Thanks for the help guys.

I waited until it started acting up again and pushing down on one on the MN3005's made it go away. Perhaps it needed to be pushed in the socket more or maybe I have a bad solder joint. It's been on since last night and still working so if it happens again I'll take it out of the box and re-flow the solder joints.

Brian this is an amazing project. It sounds great and your layout is a true wok of art!

Thanks, Charles

Hi group

I built up a MN3005 version of the Dirtbag with a Roadrage and it works great but it has weird intermittent problem. It starts oscillating out of nowhere and then after some time it goes away. It's only on the delay side and the frequency changes with the delay pot. It's a lowish clicky pulsating sound not a high squeal. It seems like a clock thing.

Any ideas?

Thanks! Charles

Hey Josh

Thanks for responding.

Yes I get no sound when grounding the diodes.

Thanks, Charles

Hi all.

I just got the Slow Loris completed and I am having a couple of problems. I am using a center off toggle switch. 1N914's and Red diffused 5mm LED's. In the center off position I get what I think is the stock Rat mode, all the controls work as expected. But this should be no diodes to ground so no distortion! I test the switch and checked that it is functioning properly, grounding the diodes as in the schematic at each position. When I test the pedal I get no sound from either the diode or LED position only in the center off. Neither the diodes or LED's are grounded in the center position. I checked the orientation and the diodes are in correctly. This is really weird! Any help is greatly appreciated.

Thanks, Charles

I going to see if my local electronics shop has those this morning and give it a try! Thanks.

I have been running it at 12V with no problem because for some reason I can't get the Roadrage to work quite right. I'll have some more time to look into it this weekend but basically the regulator is only seeing a little over 16V at it's input and is won't deliver 15V from that. Thanks, Charles.

Just to folllow up the MN3005's I got from http://retroamplis.es are legit and worked great!

But essentially if the MN3001 is happy with +15 and it's power and ground pins reversed then there's no need right? You are gaining the extra headroom from the higher supply rails. Or does -15V give the DMM some of it's voodoo? 

Hey Josh

Cool yeah I see that now. The ground and VDD pins are inverted to the 3101

Thanks for pointing that out.

Charles

Hey Josh. Thanks for your reply!

That's great advice on the sockets for the DD board. . I plan to socket all the IC's as well.

All the chips can handle 15V so that should be ok. I still don't see any where there is any inversion of the supply to negative for the MN3101 which then feeds the MN3005.

I ordered the MN3005's and MN3101 from Retroamplis in Spain. http://retroamplis.es I had a few emails with them and while they do not test them they stated they have used the same supplier for 2 years with no issues. They offered me a refund if I am not satisfied. I rolled the dice .... so I'll be out some time and return post to Spain if they are not authentic. They shipped next day and the cost was about $22 each including shipping. I feel good about it. We shall see!
I can let you know how it turns out. Here's the direct link:

https://shop.strato.com/epages/62070367.sf/sec95332916a5/?ObjectPath=/Shops/62070367/Products/IC-MN3005

The DD and LFO boards are coming from Poland so it's truly an international affair.

Thanks! Charles