From top; Bozak CMA 10-2D, Bozak CMA 10-2DL, Urei 1620 (2) ROTARY MIXER, DJ MIXER. Bozak CMA-10-2DL Owners Manual and Schematics. CMA-10-2DL Owners Manual & Module Schematics 1.3M 632k More info on the Bozak CMA-10.
The first rotary DJ mixer If it wasn’t because of the Bozak CMA-10-2DL, DJing would have never been possible during the 70s. Bozak designed the very first high quality DJ mixer in mid 60’s (the monoaural CMA-10-1 with 10 inputs) when the whole concept of mixing and “discotheques” was a brand new thing. By the 70’s, the stereo version CMA-10-2DL, had already reached quote of “the standard club mixer” status and it was extremely expensive. In late 70’s/early 80’s, Rudy Bozak kicked the bucket and there was no longer a production of Bozak mixers - until Urei/JBL took advantage on 1982 and released a Bozak mixer clone, the Urei 1620. New mixers - including the Urei 1620 - are designed using IC chips, the Bozak mixer was the only faithful mixer that was built up from ground up using resistors, capacitors, and transistors. Every component chosen carefully to be able to reach the best audio output possible.
The potentiometers was made by Allen&Bradley. The sound of Bozak has a definite shape: the bass is reproduced at the lowest bottom end (great for the old LPs), high frequencies are rounded for a warm sound, and the mids are not screetchy or harsh sounding. A Bozak mixer does not distort or deteriorates the audio output in any way. The Urei 1620 mixer has a recognizable sound, but it colors the audio output anyway. Radiata Stories Ost Rarity. The Bozak outperforms in construction quality, electronic design, and audio quality. The mic preamps on the Bozak mixer offer quiet amplification and reproduction. The Bozak mixer is fully modular with fiberglass PCBs inserted vertically through expansion slots with pins on a major horizontal routing PCB.
During maintenance or upgrading, the appropiate circuit element on a PCB can be retrived and serviced. The open expansion slots allows for sound technicians to make custom designs on the DJ mixer.
These internal features are similars to the Urei 1620. The Bozak comes with 2 turntable inputs (upgradeable to 4), 1 balanced mic input, balanced XLR and unbalanced RCA outs. It also includes a FX loop in/out where any kind of effect or processor can be plug. Bozak quick links ~ ~ ~ ~ ~ ~ More Bozak mixer information. An e-mail from Chuck McGregor of EAW company Hi Mick, Happened across your web site and have a few things to add about the subject mixer.
The ones made before about 1977-78 used Allen-Bradley not ALPS potentiometers (Type “J” for the inputs rated at something like 1,000,000 rotations.) Also the connectors for the plug-in boards were split pin gold contacts unlike the white connectors shown in your silver version interior photo. Richard Long was responsible for the “effects loop” which was added into the design at his request.