IGS Audio is a small Polish company which create boutique hand-built audio outboards for professional studio use. When looking to buy top quality audio gear one soon realize that it’s no cheap field to get into. The attention to detail, calibration, cost of parts and time it takes to build analog equalizers, compressors and mic preamps often makes some hefty price tags if you decide to go for quality pieces of gear.
IGS S-Type Compressor, humble but professional looking.
The interesting part of IGS Audio and also the reason why they caught my eye was exactly this matter. When I found their site a couple of years ago I was, after reading the specifications about the different pieces of gear they sell, surprised by the great prices they offer.
This was the very reason to why I contacted Igor of IGS Audio on the matter of getting a Mastering Edition of his Vari-Mu compressor for my mastering studio, Backstreets Mastering. While at the same time see if he was interested in getting some other pieces of his gear reviewed here at GTlounge.net. After exchanging a few mails with Igor we decided that he’d send an S-Type Mix Bus Compressor along with my order for review.
The units arrived neatly and securely packed in separate cardboard boxes. The first feeling I got when I spotted the S-Type in it’s plastic wrapping was, this looks like a real quality piece of gear! Already at that point I felt that this will be a fun review to write.
In the review below we’ll look into the build quality, features, controls, sound and performance of the S-Type compressor.
Build quality, millimeters, nuts and bolts
The 1U rack box that houses the S-Type compressor is matte black, sturdy and of high quality. It gives a nice first impression! The faceplate is painted a semi-gloss black with laser etched silver markings and text. All in all it gives a serious professional appearance to the unit without being overly blinky and space-ship reminiscent.
The VU meter is a Nissei brand that looks similar to the classic Sifam Presentor style meter with a custom bone-white IGS Audio bezel.
Close-up of the VU meter.
The connections on the back features panel mounted XLR input and output, a slow blow fuse holder and a 3 pin IEC socket for the power connection. IGS uses torx screws for the rack box so if you don’t have a T8×50 torx screwdriver you need to get one of those if you want to peek inside the box.
Back panel.
Guts
When removing the lid of the rack box to get a peek of the guts and innards of the S-type compressor, some of you might be surprised how simple a build it actually is.
Main PCB board.
Everything is basically housed on one main PCB board, with an addition of the power transformer and a small vertical mounted support board to which most of the front controls, switches and pots are fastened. The wires is neatly clamped together and carefully placed to minimize noise and interference.
Nice and tidy build.
The S-type compressor is a VCA compressor meaning that the core of the compressor is a VCA chip that, so to say, “does the work”. The original SSL bus compressor from which the IGS S-type compressor has taken it’s inspiration uses a DBX 202c VCA chip, this chip isn’t made anymore and is today very hard to get a hold of. The factory replacement when servicing a SSL consoleis the THAT 2181 chip and this is also what IGS Audio has used in the S-type compressor.
Front panel controls mounted on separate PCB.
The potentiometers used in the S-Type compressor is of the Alps brand, they feel smooth when used and are regarded to be of high quality. The switches that are used for setting Side-chain, Ratio, Attack and Release also feel really sturdy.
Controls
Looking left to right the front controls are as follows, VU Meter, Threshold, Sidechain Hz, Ratio, Attack, Release, Output, Bypass switch, On/Off switch.
- VU Meter: As noted above, Nissei with custom bone-white bezel.
- Threshold: Smooth potentiometer that ranges from -20 to +20.
- Sidechain Hz: 6 position switch. Selectable values: Off, 60Hz, 90Hz, 120Hz, 180Hz, 250Hz.
- Ratio: 3 position switch. Features ratios 2:1, 4:1 and 10:1.
- Attack: 6 position switch. Selectable values in milliseconds: 0.1, 0.3, 1.0, 3.0, 10, 30.
- Release S: 6 position switch. Selectable values in seconds: 0.1, 0.3, 0.6, 1.2, 2.0 and Auto.
- Output: Gain make-up, potentiometer that ranges from 0 to +20 dB.
- Bypass switch
- On/Off switch
The straight forward controls are topped off with some nice big chicken head knobs. No flimsy looking or feeling controls, everything is solid and sturdy!
Compared to the original SSL compressor
All in all a high quality, sturdy built unit.
The question that always comes up when a company releases a so-called “clone” or “inspired by” product, be it a hardware processor or a plugin for a DAW, is “How does it compare to the real deal?”.
Well to answer that question for you, I took the S-Type compressor with me to work to put it up against the bus compressor in the behemoth SSL G8000+ console we have there.
We ran some drum recordings through the SSL bus compressor, the S-type and also took samples without any compression on it so that you can listen for yourself and get an idea of how it sounds compared to the original piece of gear that the S-type compressor is, to some extent, based on.
The drum tracks were played out of Pro Tools HD8 directly patched to the input of the SSL consoles bus compressor and then back to Pro Tools, thus not passing through any channel strips of the console that otherwise could color the comparison clips.
The same procedure was done with the IGS S-type, Pro Tools HD8 directly to the inputs of the S-type and then back into Pro Tools. The converters we used were the standard Digidesign 192 IO.
When we started we lined the three different paths up with with a 1 kHz sine wave to get exactly the same levels going through both compressors and the uncompressed bus, so that we could an A-B-C test with SSL, IGS and uncompressed. Then we set both the SSL and the IGS compressors controls to be the same.
We decided to hit the drum clips with aggressive attack settings on both compressor as it would easier show how the two units are different from each other.
When hitting play and starting to swap between the different compressors we instantly noticed that the two units sounded different from each other. At fast attack the SSL compressor sounded a lot more distorted and colored than the IGS S-type. I presume this makes sense since it’s generally known that the newer THAT 2181 VCA that sits in the IGS S-type should provide a cleaner sound than the original DBX 202c VCA that sat in the SSL consoles compressor.
The SSL compressor is way more gritty when pushed with extreme settings like in the clips below, you’ll hear the kick drum is distorted with the SSL while the IGS S-type holds it tight and clean. Both sounds can definitely be useful, just very different from each other.
Later when tweaking the controls and A-B switching every now and then, we found that the IGS S-Type definitely share its characteristics and behavior with the original SSL compressor but at extreme settings with eg. fastest attack it is way cleaner sounding than it’s “grandfather”.
When we backed off and set a slower attack and more “gentle” values, the SSL started sounding less colored more like the IGS. But it didn’t do the same type of clean that the S-type was capable of…
Sound clips and comparison
Note that on the Ratio 2:1 clips both the SSL and the S-type compressed around 8dB on the loudest hits. With Ratio 10:1 slightly more…
Let’s take a listen!
Uncompressed clip
SSL Bus compressor Ratio 2:1
Threshold: -15
Makeup: +15
Attack: 0.1mS
Release: Auto
IGS S-type Ratio 2:1
Threshold: -15
Makeup: +15
Attack: 0.1mS
Release: Auto
Side-chain: Off
…some more aggressive Ratio settings below
SSL Bus compressor Ratio 10:1
Threshold: -15
Makeup: +15
Attack: 0.1mS
Release: Auto
IGS S-type Ratio 10:1
Threshold: -15
Makeup: +15
Attack: 0.1mS
Release: Auto
Side-chain: Off
Conclusion
So what’s the final verdict on the S-type compressor? Well, while inspired by the SSL bus compressor it doesn’t sound the same. It’s more transparent and doesn’t implement the same amount of “mojo” in lack of a better word. But it’s much more versatile and user-friendly as it has more controls, among other things the very usable side-chain filter. When used on whole mixes it’s really an indispensable thing to have, as soon as things are a little more complex and you still want to retain the punch, groove and clarity of the kick drum and bass… turn on the side-chain filter and vóila!
If you are looking for your first outboard stereo compressor a word like transparency might sound slightly boring to you, as you think you can do the transparent thing in the box and need something colorful and gooey. But don’t let clean turn you down, while being transparent it still adds things that’s on another level that your regular DAW compressor and being more transparent than the original SSL bus compressor is actually a good thing in my opinion. Especially for those who don’t have racks of outboards as it will automatically make the compressor suitable to a much wider range of material and tasks!
The IGS S-type compressor has an extremely good price-quality ratio compared to a lot of similar products out there on the market. While a price tag of 1190 € isn’t cheap, when it comes to hand-built professional quality analog gear it is quite an awesome price for a stereo compressor.
I was very satisfied with the unit when I tested it and if I was on the look-out of a “SSL style” bus compressor the IGS Audio S-type would definitely on the top of my list. Being solidly build, having quality switches and controls, superb sound and a price tag that doesn’t break the bank… you can’t go wrong with this one!
- For more information on the S-type and other products, check out the IGS Audio webpage.
- You will also find IGS Audio on Facebook.
