MICROCOMPRESSOR STEREO - compact stereo VC compressor for eurorack modular synths.
This is compact but hi-quality compressor. I used THAT4301 dynamics processor.
THAT 4301 Dynamics Processor, dubbed "THAT Analog Engine®", combines in a single IC all the active circuitry needed to construct a wide range of dynamics processors. The 4301 includes a high-performance, exponentially-controlled Blackmer® VCA, a log-responding RMS-level sensor and three general-purpose opamps.
Design is based on THAT Corp. design notes - Fully Adjustable Compressor / Limiter. This is a feedforward VCA compressor.
- Adjustable by potentiometers Treshold, Ratio, Attack, Release, Makeup gain.
- Reduction LED which lights when signal level exceeds treshold.
- Treshold, Makeup, Attack and Release can be controlled by CV.
- Hard/soft knee switch.
- Two timing modes are available -- auto and manual. In auto mode attack and release rates are linked, and depend on the non-linear capacitor circuit. In manual mode, variable, independent adjustments of the attack and release dynamics are possible.
- Peak or Automatic timing detector options.
- Sidechain in to external sidechain processing.
- Envelope out allows to patch any VCA as compressor.
- Full reverse polarity protection.
Power consumption: V+ 43mA, V- 30mA.
PCB - 2mm thickness, gold platted, black mask. $30
Two panels - 16HP front & back. Anodized alu, black print. $35
SMD parts + soldering. $15
Shipping per set: $5 - only board, $8 - board+panels.
TOTAL for complete set with shipping: $88
Assembled module $330 + $15 shipping.
MUFFWIGGLER forum thread http://www.muffwiggler.com/forum/viewtopic.php?t=101764
Soundsample. Tube VCA works as compressor modulated from envelope out of Microcompressor. Filter - Mutant vactrol VCF. No effects.
Sample made by Jim Sutherland www.jimsutherland.uk.com/
Distorted drums in punk style are heavy compressed. Jim modulated Makeup from Envelope Out to have extremally strong compression.
SHOPPING CARTS :
L-1 Stereo Compressor - Mouser shopping cart http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=4a34b f6189
MERCHANDISE TOTAL: $66.26 (USD)
Parts not included in Mouser shopping carts:
5 potentiometers (10K linear X 2, 50K linear X 3)
IC sockets - 20-pin X 2, 8-pin X 1.
Where to buy?
pots: http://smallbear-electronics.mybigcommerce.com/alpha-single-gang-9mm-r ight-angle-pc-mount/
pots: 50K http://www.taydaelectronics.com/potentiometer-variable-resistors/rotar y-potentiometer/linear/50k-ohm-linear-taper-potentiometer-round-shaft- pcb-9mm.html
10K http://www.taydaelectronics.com/potentiometer-variable-resistors/rotar y-potentiometer/linear/10k-ohm-linear-taper-potentiometer-round-shaft- pcb-9mm.html
I included into Mouser shopping cart 8 Kobiconn jacks. But they need to solder a leg for ground connection.
Better choise is Inline jacks:
1. Thonk: http://www.thonk.co.uk/shop/thonkiconn-3-5mm-jack-sockets-x50/
2. Erthenvar: http://erthenvar.myshopify.com/products/3-5mm-inline-jacks
THAT chips on Etsy:
Some cheap LEDs have bad legs isolation at the cap, and they may short to the panel. Check conductivity in a place where LED touch the panel before installing.
PCB with soldered SMDs:
MONO MICROCOMPRESSOR EURORACK (discontinued)
OLD VERSION PCB (still in stock)