Constrictor build

[mybud]

Build Rating

5.00 star(s)

Ok, so I’ve been on a bit of a boxing (them up) jag of late, while I wait for new stuff to arrive. Here’s the constrictor with two useful mods from this here forum, for which many thanks to @szukalski, @Chuck D. Bones, and @DSpenceATL.

One is to break the gain trimmer out as a pot, very useful for me as I can set it for passive bass, active bass, or HB-equipped guitar. T’other is a little compression indicator light to help find the appropriate settings for these different instruments. The dreaded white foot switch washer (frowned on in these parts, or so I’m told) is actually a bypass/active indicator and keeps things tidy, given the complete absence of metalwork skills on my part.



What does it sound like? Well, it certainly smooths over some rough edges in my playing and gain reduction is quite evident. With the additional adjustment to the pots, it’s possible to drive it into distortion, in itself quite interesting.

I need to hang with it a bit longer but so far, so good. As ever, thanks for reading and may your builds all go smoothly and successfully.

 

[MichaelW]

This is still one of my favorite compressors so far. Subtle but effective and transparent. I've got the MBP Roughcut on the bench right now though.....heard a lot of good things about that one too.

 

[mybud]

This is still one of my favorite compressors so far. Subtle but effective and transparent. I've got the MBP Roughcut on the bench right now though.....heard a lot of good things about that one too.

Yeah, I’m not over fond of compression as a rule but this and the Byrdhouse rock.

‘Everybody in the whole cell block, Was grooving’ to the Byrdhouse rock,’ or some such.

I’ve occasionally experienced heavy-handed over-compression on bass where you have to accommodate the engineer’s settings. Rarely enough TBH, but neither of these does that. There’s no adjustment required to one’s attack IOW and they don’t mangle your sound.

In fact, beyond groovy

 

[mybud]

Yeah, I’m not over fond of compression as a rule but this and the Byrdhouse rock.

‘Everybody in the whole cell block, Was grooving’ to the Byrdhouse rock,’ or some such.

I’ve occasionally experienced heavy-handed over-compression on bass where you have to accommodate the engineer’s settings. Rarely enough TBH, but neither of these does that. There’s no adjustment required to one’s attack IOW and they don’t mangle your sound.

In fact, beyond groovy

Oh yeah, brief addendum. I have the Kompromat from MBP on my upcoming build list. So, for someone who’s not nuts about compressors…?

 

[MichaelW]

Oh yeah, brief addendum. I have the Kompromat from MBP on my upcoming build list. So, for someone who’s not nuts about compressors…?

Ok in full disclosure I also have the MBP Oracle board. It will be my first non-opto DIY compressor. Really looking forward to that one since everyone raves about the Boss CS-3.....I just got the THAT2181 in the mail today. Woohoo!

 

[ac30irons]

Hey dude, I’m just about to build the Constrictor once I find out how this bloody Opto thing goes on. Are you able to share how you did the gain break out ? Cheers

 

[SYLV9ST9R]

Hey dude, I’m just about to build the Constrictor once I find out how this bloody Opto thing goes on. Are you able to share how you did the gain break out ? Cheers

Just wire the trimmer as a third potentiometer. Did it on one I built, but wish I did that on mine.
@mybud how do you add the compression LED?

 

[ac30irons]

How is the question? I’m pretty clueless. My guess is use a A10k pot and wire as standard with with 1 being the square pad on the trimmer ?

 

[mybud]

Just wire the trimmer as a third potentiometer. Did it on one I built, but wish I did that on mine.
@mybud how do you add the compression LED?

Solution from Chuck D. Bones - “Try installing an LED and limiting resistor from IC2-7 to IC2-1. LED cathode toward IC2-1, same as the VTL5C10. Keep the limiting resistor larger than 1K so as to not steal too much current from IC2.”

 

[mybud]

How is the question? I’m pretty clueless. My guess is use a A10k pot and wire as standard with with 1 being the square pad on the trimmer ?

Yes, that’s correct. So 1 to square pad, wiper to middle, 3 to left hand pad. Hope the pic helps.

 

[ac30irons]

It really does help. I can just see the angled cut on the Opto so I think mine needs flipping also. May socket to be sure though !

 

[MichaelW]

Here's a pic of the orientation on mine.

Don't know which brand vactrol you have but mine look like the below. When I was building mine I assumed the convention of the longer leg being the anode of the diode side and it worked for me.