madbeanpedals::forum

Projects => General Questions => Topic started by: nzCdog on February 07, 2020, 01:50:32 AM

Title: CA3080? For Ross style compressor
Post by: nzCdog on February 07, 2020, 01:50:32 AM
Hey all!  :)

I'm hoping to build a sweet little compressor pcb which Jason (jubal81) kindly sent me... several years ago!
It needs a CA3080 OTA, I was wondering are those cheap ones on eBay legit?  Any suggestions?

Thanks
Title: Re: CA3080? For Ross style compressor
Post by: gordo on February 07, 2020, 02:00:34 AM
Kind of a crap shoot.  If it's socketed and they're cheap it can't hurt.  Plan B could be to pick up the real thing from Small Bear.
Title: Re: CA3080? For Ross style compressor
Post by: somnif on February 07, 2020, 02:04:09 AM
In my experience, the handful of 3080's Ive bought from Ebay have all, to a one, been fake/dead. But I'm just one data point.

There are a number of webshops that have genuine chips in stock, but not sure if that will be your best option (depending on shipping and pricing and whatnot)
Title: Re: CA3080? For Ross style compressor
Post by: nzCdog on February 07, 2020, 03:20:00 AM
Thanks for the replies amigos! :)
Sounds like it is as I suspected with eBay then.  Trying to keep the cost down because student... And smallbear is out of stock from what I can tell.  I hear there are workalikes out there, might have to do some more research
Title: Re: CA3080? For Ross style compressor
Post by: tcpoint on February 07, 2020, 03:49:35 AM
You can sub the CA3080 for the LM3080.  National licensed the design.  If there are any differences, they are minimal.
Title: Re: CA3080? For Ross style compressor
Post by: nzCdog on February 07, 2020, 04:27:12 AM
Thanks tcpoint.  I decided to take a punt with a LM3080 from eBay. ;D
Title: Re: CA3080? For Ross style compressor
Post by: alanp on February 07, 2020, 04:32:00 AM
You can also use half a LM13700.
Title: Re: CA3080? For Ross style compressor
Post by: Betty Wont on February 07, 2020, 02:35:13 PM
Quote from: alanp on February 07, 2020, 04:32:00 AM
You can also use half a LM13700.
This^
Title: Re: CA3080? For Ross style compressor
Post by: matmosphere on February 07, 2020, 03:18:37 PM
http://effectslayouts.blogspot.com/2015/11/lm13700-to-ca3080-conversion-board.html?m=1
Title: Re: CA3080? For Ross style compressor
Post by: NorthCoast on February 07, 2020, 05:53:10 PM
https://tagboardeffects.blogspot.com/2012/10/emma-transmorgrifier.html

"This daughterboard can be used with any of the effects in this blog which use the CA3080, including the MXR DynaComp, Ross Compressor and Keeley Compressor."
Title: Re: CA3080? For Ross style compressor
Post by: nzCdog on February 08, 2020, 12:30:57 AM
Cheers all.  Good to know the other options in case eBay fails :)
Title: Re: CA3080? For Ross style compressor
Post by: jimilee on February 08, 2020, 01:07:22 AM
Quote from: NorthCoast on February 07, 2020, 05:53:10 PM
https://tagboardeffects.blogspot.com/2012/10/emma-transmorgrifier.html

"This daughterboard can be used with any of the effects in this blog which use the CA3080, including the MXR DynaComp, Ross Compressor and Keeley Compressor."
Does anyone make the Emma PCB? I've been thinking about building one for about 4 years now. That's a lot of vero. I could do it, but I'd like not to. Hi jack over.


Sent from my iPhone using Tapatalk
Title: Re: CA3080? For Ross style compressor
Post by: skyled on March 04, 2020, 02:35:57 AM
Is it possible to split the LM13700 into two separate CA3080's? I've only ever seen it with one of the CA3080's being used.
Title: Re: CA3080? For Ross style compressor
Post by: alanp on March 04, 2020, 03:58:56 AM
The LM13700 comes with two OTA, independant. Most "adaptor" boards use only one.
Title: Re: CA3080? For Ross style compressor
Post by: jimilee on March 04, 2020, 03:21:49 PM
I bought mine from small bear, I'm building a comp also.
Title: Re: CA3080? For Ross style compressor
Post by: Marshall Arts on March 04, 2020, 05:24:45 PM
Quote from: nzCdog on February 07, 2020, 04:27:12 AM
Thanks tcpoint.  I decided to take a punt with a LM3080 from eBay. ;D

May I ask where and how it went? Looking for some 3080s myself...
Title: Re: CA3080? For Ross style compressor
Post by: nzCdog on March 05, 2020, 08:22:13 PM
Haven't got it assembled yet, I am somewhat prone to distraction. The vendor was 'little diode' I the UK. I've had dealings with them before, so not expecting issues :)
Will update once done
Title: Re: CA3080? For Ross style compressor
Post by: nzCdog on March 07, 2020, 07:39:54 PM
And... Yup all working ok! :)