The most well known audio compressor that uses a diode bridge as the gain reduction element would have to be the Neve 2254. This is not a copy of that unit - but it is the inspiration for the DBC-20 design. The audio path features our Class A discrete BE41 amplifiers in a balanced configuration throughout, and for extra colour, we have a custom "radio steel" laminated transformer coupling into the diode bridge. This combination produces a vintage character that can best be described as tight, colourful and rich with harmonics!
Our unique side chain design re-creates the style of compressors from the 60's (think Fairchild) whereby the compression ratio is progressively increased with deepening gain reduction. So as the input signal increases past threshold, the ratio will vary from 1:1 right up to 15:1. This feature allows for the control of very dynamic signals (such as vocals) in a seamless fashion and is also a very desirable characteristic when used on complex percussive material such as the drum buss and drum loops. On the mix buss the DBC-20 adds perfect analog colour to "in the box" mixes.
This compressor is easy to get happening with six switched attack and release times covering a wide range, including an interesting auto release mode. Big knobs are provided for the amount of compression and the output gain control. The compressor can be switched to a Soft mode whereby dynamic peaks are partially retained. Another switch introduces a high pass filter to the side chain to lower compression sensitivity at low frequencies which is useful on the mix bus. The large knobs with pointers allow for accurate resetting of the compressor and the fast response 15 LED bar graph meter accurately displays gain reduction.
The lower cost of the DBC-20 is not achieved by using cheap parts, instead with clever design we have reduced the amount of time it takes to assemble and align each unit!
GAIN - variable pot that adds gain at the output to correct for lost level with 15dB range.
COMPRESSION - variable pot that sets the amount of compression.
ATTACK - rotary switch with 6 settings, FAST (less than 0.5mS)-5mS-10mS-15mS-25mS-50mS.
RELEASE - rotary switch with 6 recovery time settings, 50mS-100mS-200mS-400mS-600mS and AUTO.
HARD/SOFT - adds dynamics in soft mode for times when very light compression is required.
FLAT/BASS - reduces compression sensitivity at low frequencies for more bass punch, approx 8dB at 100Hz.
BYPASS/ENGAGE - hard wire unit bypass to compare compressed and uncompressed signals.
There is also a handy power ON/OFF switch and the LINK A/B which provides for stereo tracking to prevent image shift when used on the mix buss.
Wow, just received my new [DBC-20] compressor and installed it today. Who'd have thought diodes could sound so good! I am so pleased, I had to let you know. Beautifully thought out, excellent controls, clear metering, wonderful sound. I'm now thinking of getting an ARC, looks like it'd be amazing for recording vocals.
So, I've had my DBC for a while now, and I gotta say, this thing is amazing! First use was on drum overheads, and you can really shape the sound with the DBC. Fast attack is really quick, totally smears off the transients, great for a parallel compression type of usage, or you can do slow attack, fast release for an SSL-kinda thing. I ended up somewhere in between, with the 10ms attack and 100ms release for adding a little "smack" to the front of the snare hits, while also bringing up the tone and ambience. Whatever you want it to do, it always sounded great.
Piano on another mix was the next use, and here it also sounded great. The HPF switch helps reduce pumping, and again, the attack control and the hard/soft ratio switch enables you to go from mild control to full-on pumping for a Beatles-esque compression swell effect. The flexibility does mean, however, that you can set it wrong and get pumping, or un-natural sounding compression. This is not a set-and-forget box.
Final use on today's mix was for double-tracked acoustics, using the L and R channels independently. Fast attack and auto release with the side chain HPF switched in, doing just a couple of dB's of gain reduction just helped to tame the peaks and increase the sustain of the acoustics, adding a slight sheen and sense of authority to the sound, making them sound much more expensive than they were! I haven't tried it on the mix buss yet, but I have no doubt that it will be great.
I have used the MA2.2 and the ARC before, but this is my first Buzz purchase, and I can see myself using the DBC-20 on something on every mix I do. It's that good!
UK producer/engineer/mixer. Adrian Hall's website
Click here to hear some sound clips from Adrian.
Maximum Input Level; +27dBu
Maximum Output Level; +27dBu
Noise; -80dBu (measured A Weighted with 10dB gain applied)
Gain; variable 0dB to +15dB
Frequency Response; 6Hz to 400kHz measured no gain reduction
Harmonic Distortion; At +10dBu input level, no gain reduction; 0.28% @ 100Hz, 0.25% @ 1kHz, 0.15% @ 10kHz
Harmonic Distortion; With 10dB gain reduction (Release set to 400mS); 1.5% @ 100Hz, 0.5% @ 1kHz, 0.5% @ 10kHz
Standard Operating Level; +4dBu
Size; 1 Unit 19" rack mount, (482Wx44Hx250D)
Power requirements; 230V/115V selectable, IEC detachable power cable.
Specifications are typical of a production unit and are subject to change without notice.
0dBu reference = 0.775 volts RMS.