My '77 Dyna Comp Clone Project

[Steve Mavronis]

It's not done yet but this is what it will look like...

I just got finished applying the ID-Mark aluminum label and bolted everything through the holes as a dry test fit. I think it's looking nice but just praying I didn't make any PCB layout mistakes and have to redo another board design. Before I do the wire routing inside I'm contemplating making a nice little wiring harness using header pin connectors to be able to disconnect the DC jack and PCB If wanted. Probably overkill, I dunno.

[Xplorer]

nice work ! you must be happy !
please post some clips when it's finished.

[Steve Mavronis]

Damn - It actually works!!!

Just finished wiring it up. I was almost going to wait in case it failed but now I can sleep easy. It's like 3:30am and have work in the morining so I'll give it a more thorough test Friday evening and upload a gut shot etc. I haven't tried adjusting the trim yet but didn't notice any distortion. I've never used a compressor before so this effect is new to me. Good night...

[Steve Mavronis]

Here are final completed pics of my latest build, my take on a reverse engineered clone of the 1976-1977 era MXR Dyna Comp. Custom PCB layout designed in ExpressPCB and graphics made with GIMP. Special thanks to Rick (Frequency Central) and Pete (Scruffie) for their CA3080 donation offers that helped make this project possible! I'll build one more copy to serve as a spare backup using the other CA3080. I've never used a compressor effect before so this is all new to me! Thank you for following this thread. This project is done!

[Wattever]

WOW! Very nice work!

I like the steps you put in the long leg of the resistors to keep them perfectly upright while soldering, nice touch.

If it works half as good as it looks, you've got a great pedal there.

I feel like I should say that you've done a really professional job on this, but it's SO much better looking than any professional one I've ever seen.

Keep up the good work.

Mark

[Steve Mavronis]

Thanks! I'm working on documentation to share in case anyone wants to try and build one using my PCB layout pattern, which I will prepare and post later on my (non-commecial) Neo-Classic Effects website on Google. For now, here is a draft layout parts guide I'm working on:

[Steve Mavronis]

Here's everything I've built so far together, minus the noise suppressor:



Strat->NS2send->Compressor->Overdrive->NS2return->Amp

[MikeO]

very nice work man!! I love compressor pedals, i've owned just about every one of them at one time or another. My favorites are the Boss CS-2 and the Dyna Comp. I wish i could hear yours

[Steve Mavronis]

Anyone know the difference between CA3080S and CA3080A metal cans? What CA3080 version did the old script Dyna Comp use? Any advantages/disadvantages to these metal can end letter designations and/or vs DIP-8 chip versions? Some say metal cans are quieter but any measured proof of that?

[Colossal]

Beautiful work Steve, really nice. I especially like the board layout and resistor placement as shown here:

[Steve Mavronis]

Thanks, it would have been impossible to do on that small boad size without vertical mounted resistors.

Oh, and one change I made last week was swapping out all five socketed transistors to 2N5088's instead. They are slightly less noisey than the MPS5172/2SC1849 combo and it sounds the same, perhaps a bit smoother volume leveling compression. And I just got some CA3080A metal can IC's and wondered what the A vs the S designation meant.