abechap024

PRR 176 vari-mu (check first post for docs)
« on: June 11, 2011, 01:44:11 AM »
UPDATE(10/14/2011):

WIRING GUIDE www.acsoundstudio.com/prr_176/PRR_176_WIRING_GUIDE_j.jpg
BOM www.acsoundstudio.com/prr_176/prr_176_bom_1.pdf
Schem www.acsoundstudio.com/prr_176/PRR_SCHEM_ALL.jpg
OFF BOARD RECTIFICATION www.acsoundstudio.com/prr_176/OFF_BOARD_POWER.png  <solves all hum issues, no need to mount transformers off board>


Errata: If using INA134 input de-balancers, on left channel connect pin 1 to ground (a convenient spot is pin 8 of the same chip) and use shielded transformers for input, or move left channels input TX away from power supply for best S/N.

Hello,
This is my take on the mash up of the 176 vari-mu compressor and the PRR sidechain. It 2 channel stereo/mono switchable - Receiver chip input, or transformer balanced input. Uses a 6bc8 tube for muing action. Separate front panel Lorin switch PCB, 12 position stepped input/output, 6 attack/6 release positions. 3 on-board input and interstate transformer options: Cine-mag, Edcor. Jensen can be wired in. Driver output or transformer output. And it all fits in 1RU.

All signal-chain opamps have a dip-8 footprint and a 2520 style footprint for your discrete opamp fans.

I prototyped it on a breadboard and it sounds really great.

I'm posting the schematic for any improvements/ideas.


Thanks as always,
Abe
« Last Edit: April 27, 2012, 10:01:41 AM by abechap024 »
AC Sound - some DIY circuitboards


dustbro

Re: PRR-176 vari-mu
« Reply #1 on: June 11, 2011, 03:07:33 PM »
looks really cool
thanks!

strangeandbouncy

Re: PRR-176 vari-mu
« Reply #2 on: June 11, 2011, 03:13:59 PM »
Blimey . . .



  I was just thinking about something similar, but never gonna get it together . . .


   Abe, you truly are a demon-fiend . . . dont you ever sleep . . .


      Very excited,


      ANdyP
. . . . RUH ROH . . . . .

abechap024

Re: PRR-176 vari-mu
« Reply #3 on: June 11, 2011, 03:16:31 PM »
haha well a lot of times I just sleep on the couch in my shop....so It makes getting to work that much easier.
Cheers,
Abe
AC Sound - some DIY circuitboards

tomcat

Re: PRR-176 vari-mu
« Reply #4 on: June 11, 2011, 07:06:25 PM »
Dont burn all my money you evil  ;D

abechap024

Re: PRR-176 vari-mu
« Reply #5 on: June 11, 2011, 07:08:33 PM »
Hahah! Yes I see you guys are onto my evil plan....try to take over the world through VARI-MU! bWAhaHahAha!

These fill me with such evil love I don't think anyone should be deprived of one. I'm thinking in the ballpark of 35$ for a stereo set.


Cheers,
Abe
« Last Edit: June 11, 2011, 07:39:53 PM by abechap024 »
AC Sound - some DIY circuitboards

tomcat

Re: PRR-176 vari-mu
« Reply #6 on: June 11, 2011, 08:11:16 PM »
$ 35 including PSU, Case, Tubes,.... ;D   Thats the evil thing. You tease us with pcbs and then we are lost in the mouser/digikey/... hell ;)

abechap024

Re: PRR-176 vari-mu
« Reply #7 on: June 11, 2011, 08:53:40 PM »
Haha!

So now you want a BOM with all the mouser parts too!?!? that takes all the fun out of it! ;)
 But I'll see what I can do......


If there is enough interest we could do a parts kit...



Its worth it....its true what they say...you gotta go through hell to get to heaven!
AC Sound - some DIY circuitboards

abechap024

Re: PRR-176 vari-mu
« Reply #8 on: June 11, 2011, 08:59:13 PM »
It makes sense to do a resistor kit, cause to me when I'm building a project, getting the resistors can be the most tedious part....no one selects resistors on their sound like you find with capacitors and what not(not many people at least). And its the most time consuming to sit there and add a resistor to your cart one...after one.....after one....after one at a time.

I can just get a bunch or resistors and spend a day or two putting them into baggies....

Your Master of Hell  ;),

AC
AC Sound - some DIY circuitboards

Neil

Re: PRR-176 vari-mu
« Reply #9 on: June 11, 2011, 10:16:53 PM »
Dammit, I'm in.


dandeurloo

Re: PRR-176 vari-mu
« Reply #10 on: June 11, 2011, 11:10:34 PM »
Haha, you know what I think!
PROFESSIONAL CHASSIS AND FRONT PANELS FOR DIY PROJECTS: WWW.COLLECTIVECASES.COM

Dan Deurloo
www.collectivecases.com
www.risendrums.com

abechap024

Re: PRR-176 vari-mu
« Reply #11 on: June 12, 2011, 12:25:38 AM »
Haha, you know what I think!

Good :) Your going to offer cases for this right?


AC Sound - some DIY circuitboards

mylesgm

Re: PRR-176 vari-mu
« Reply #12 on: June 12, 2011, 12:47:59 AM »
now this is something I've been waiting for for awhile.  What about adding a hpf to the sidechain?
A kit would be cool or at least a partial kit for the main parts ie power transformer, any usual caps etc.
A case would also be cool.  What sort of meter will this require?  Edcor transformers?

Check my work at www.mylesmumford.com

abechap024

Re: PRR-176 vari-mu
« Reply #13 on: June 12, 2011, 01:00:05 AM »
now this is something I've been waiting for for awhile.  What about adding a hpf to the sidechain?
Yep already got the HPF on the sidechain, just forgot to mention it :)
Quote
A kit would be cool or at least a partial kit for the main parts ie power transformer, any usual caps etc.
A case would also be cool.  What sort of meter will this require?  Edcor transformers?
I'll have to look into ordering a mass of edcors to see if these is a discount. Also offering transformers (mainly power transformers) with kits the shipping really starts to add up especially with international shipments. I figure most people can probably access power transformers closer to home. For people running 110v mains its nice cause you just need a dual pri&sec 15v transformer. but for people running 220v mains you are going to need to get the 220v down to 100v and also 15v.


[/quote]
AC Sound - some DIY circuitboards


Re: PRR-176 vari-mu
« Reply #15 on: June 12, 2011, 03:36:38 AM »
Huh, so you plan to do a PCB for this contraption?
May I humbly suggest making it a LARGE pcb, as opposed to tightly packed pcbs?
Like, so one could fit 2w resistors on it and such?
Or, desolder something from the middle of the board without other components getting in the way?
 ::)

tomcat

Re: PRR-176 vari-mu
« Reply #16 on: June 12, 2011, 11:19:47 AM »
Im in for small pcbs (like to build small 1u stereo versions), no normal parts necessary. Dont need mouser or digikey bom as well ;)

Abe, maybe you should rethink the "include resistors" thing. Instead of counting resistors (which is not so great fun) you should follow your evil nature and create new pcb projects ;) More fun for you, more tempting projects for us :)

0dbfs

Re: PRR-176 vari-mu
« Reply #17 on: June 12, 2011, 12:43:13 PM »
I'll go in for a couple of these. Planning to get my pye and eat it too !  Btw, this is getting completely out of control.

Best,
jb
Music is everything!
Audio is everything else!

strangeandbouncy

Re: PRR-176 vari-mu
« Reply #18 on: June 12, 2011, 01:44:53 PM »
Hi Abe,




  just one more question, erm . . . . .when dey come . . . .



       me in, big time . .\



    ANdyP

. . . . RUH ROH . . . . .

shabtek

Re: PRR-176 vari-mu
« Reply #19 on: June 12, 2011, 01:45:18 PM »
I would like to see a schematic--what you've posted is more of a wiring or troubleshooting diagram.
all the IO options are not as important as the sidechain and GR elements are.
+1 for bigger board and plated through holes to allow for swapping of parts... especially since you're designing for options.
"really fine players do not use stomp boxes or master volume, they match the amp to the room and turn it up to 11.  Stevie Ray, BB King, Albert King, Duane Allman, Dicky Betts, Louis Armstrong"
   -CJ