Buss compressor – recommendations, please

Help Support GroupDIY:

Claudio

Well-known member
Joined
Dec 9, 2017
Messages
55
Hello everyone,

A friend of mine is looking for a buss compressor other than the (G)SSL. The only one I can think of right now that I would typically use on a stereo buss is an LA2A. But I’m sure there are other DIY models that are suitable. Something like a Fairchild 660/670 or API 2500 perhaps? Could someone fill me in, please? I’m obviously looking for a (slightly advanced beginner’s) DIY kit, VPR or 19" standalone. A dry/wet option would be nice, too.

Thanks!
Claudio
 

shot

Well-known member
Joined
Nov 28, 2008
Messages
651
Location
Zagreb, Croatia
You could basically use any compressor on your drum buss or mix buss as long as it sounds good!
But what would be a definition of buss compressor? Well, that would probably be excellent stereo tracking.
Most compressors can be built twice, racked into same enclosure and set to the same knob positions to behave same on both channels. Most have means to link controls but that's just linking - not true stereo detector on sidechain.
But GSSL (or MixBuzz, SB4000) are true stereo compressors and that makes them favorite on buss duties.

For instance I prefer PYE compressor by AbeChap since it is transparent even at high gain reductions.
But that is two compressors in one enclosure and I don't rely on it's link feature...

:)

Luka
 

Script

Well-known member
Joined
Nov 26, 2008
Messages
1,556
Location
Japan
Some claim that two compressors that do not track perfectly in stereo yield that huge 'oceanic' sound of the 1970s... Anyway, it's also a feature (sort of) on the API2500.
 

scott2000

Well-known member
Joined
Feb 21, 2015
Messages
2,693
Location
Sunny...Sometimes Florida- USA
Script said:
Some claim that two compressors that do not track perfectly in stereo yield that huge 'oceanic' sound of the 1970s... Anyway, it's also a feature (sort of) on the API2500.

I think Bob Katz even mentions that not using the linking function will yield better stereo separation in his book.....So you can run mixes through his book....lol....Meaning I read it in his book........ :D

I've even experimented with different op amps in left and right channels in some things... Pretty interesting... I'd love to hear a diy build that is recommended for this application as well.....
 

Claudio

Well-known member
Joined
Dec 9, 2017
Messages
55
shot said:
You could basically use any compressor on your drum buss or mix buss as long as it sounds good!
But what would be a definition of buss compressor? Well, that would probably be excellent stereo tracking.
True. But I guess you’d also want the compressor to be as unobtrusive as possible. In a stereo buss, it’s not there to add color and harmonics, but only to control levels and glue everything together.
 

ruairioflaherty

Well-known member
Joined
Jul 6, 2005
Messages
2,307
Location
Los Angeles
Claudio said:
Do you know any DIY clone of the API 2500?

3 reasons not to clone it
- It's still being made commercially
- There isn't a schematic, pcb or kit available
- It's sounds horrible (IMO)

I've tried a lot of compressors. A lot.  For my work in mastering my favorite all rounder is a modified SSL FX384.
 

shot

Well-known member
Joined
Nov 28, 2008
Messages
651
Location
Zagreb, Croatia
Script said:
Some claim that two compressors that do not track perfectly in stereo yield that huge 'oceanic' sound of the 1970s... Anyway, it's also a feature (sort of) on the API2500.

That might be true! (but not in every situation)
I have very well matched pair of Pico (mono) compressors and I found out that I like imaging better when I leave them unlinked. I almost always use them as separate channels.
 

ruairioflaherty

Well-known member
Joined
Jul 6, 2005
Messages
2,307
Location
Los Angeles
Michael Tibes said:
So what is your modification - if you care to share?

Michael

Unfortunately I don't know the specifics as it's not my unit.  The audio path has been completely replaced and has different IO buffers (unbalanced) and a different VCA setup. 

It's hard to beat the SSL for all round control.
 

Script

Well-known member
Joined
Nov 26, 2008
Messages
1,556
Location
Japan
Claudio said:
Do you know any DIY clone of the API 2500?
Most certainly: Nope.

If you were looking for an API2500 clone I'd suggest buying the 'kit' from them directly. The best part: It comes in a genuine case and is readily built, saving you a lot of time ;) You could then easily open it up any time and modify it. I only picked up on your mention of the API cos it has that function to 'unlink' or 'semi-link', which is something that goes contrary to the idea of 'perfect' RMS stereotracking.

If your friend doesn't like the (G)SSL, why not look at the several takes of it on this forum, including upgrades and modifications in the audio path etc etc. I agree that it implies a lot of research and leafing through long threads. But it might be worth the effort, last but not least because it would definitely make it a more advanced DIY project. When finished just don't call it anything SSL related on the faceplate  8)

Maybe first settle on a compression type/technique? Several options, though not all DIY projects on this forum can be stereolinked easily.
- VCA
- opto
- tube
- PWM
- diode bridge

Another idea is to buy a (semi-serious) compressor cheap off ebay (or the like) and modify the hell out of that (including adding functions). There should be plenty of inspiration for that on these pages.
 
Top