DBX 166 Modifications/Upgrades

These Mods clean up the DBX166 compressor making it high quality PRO Studio Gear.

PSU MoD: – Replace c3 ,c4, c7, and c8 with 1000uf-2200uf 35v caps
– Replace c5 and c9 with a .1uf film cap (preferably polypropelene)
– Bypass c6 and c10 with .1uf film caps
Channel 1:

IC MoD: – Replace chip OA1 with better ic (NE5532, OPA2132, opa2134, OPA2107, LT1358, or LME49860NA (My fav)) and install a gold plated ic socket.
– Repalce chip OA2 with better ic (LME49710NA, OPA134, OPA602, opa627, or LT1357) and install a gold plated ic socket.
– Replace the VCA IC1 with a THAT 2180AL08-U (lift pin 4, pin 4 should not connect to anything)
– Add a 47pf NPO ceramic cap from pin 3 of OA2 to ground (Suggested by Jim Williams)

Capacitor/resistor MoD:
– Replace c14 with a 22uf 35v bipolar cap
– Bypass that with a .22u film cap
– Note: c14 was originally a 3.3uf cap. You could fit in a film cap in there if you are carefull.
– Replace c25 with a 22uf 35v bipolar cap
– Bypass that with a .22u film cap

– Replace r17 and r18 with 22ohm metal film resistors
– Replace r1 and r4 with 1k metal film resistors
– Replace r3 and r6 with 7.5k metal film resistors
– Replace r2 and r5 with 10k metal film resistors
– Replace r7 and r13 with 2k metal film resistors

IC Control Voltage (Optional) MoD: Turns this compressor into a beast.
– Replace chips OA3, OA4, and OA5 with gold plated ic sockets and a better ic like a LT1124 or LME49860NA.

Peakstop switching MoD: Turns on and off the peakstop circuit.
– Drill a hole in the front plate about .25 inches diameter. Install and wire in a DPDT gold contact switch here. Lift one end of CR5 and CR6. Solder 2 wires. One to cr5 and one to cr6 and solder the other end of the wires to each center contact of the DPDT switch. Solder 2 more wires to the vacant holes of cr5 and cr6 and wire these to one side of the switch.

Channel 2:

IC MoD: – Replace chip OA6 with better ic (NE5532, OPA2132, opa2134, OPA2107, LT1358, or LME49860NA (My fav)) and install a gold plated ic socket.
– Repalce chip OA7 with better ic (LME49710NA, OPA134, OPA602, opa627, or LT1357) and install a gold plated ic socket.
– Replace the VCA IC8 with a THAT 2180AL08-U (lift pin 4, pin 4 should not connect to anything)
– Add a 47pf NPO ceramic cap from pin 3 of OA2 to ground (Suggested by Jim Williams)

Capacitor/resistor MoD:
– Replace c14 with a 22uf 35v bipolar cap
– Bypass that with a .22u film cap
– Note: c14 was originally a 3.3uf cap. You could fit in a film cap in there if you are carefull.
– Replace c55 with a 22uf 35v bipolar cap
– Bypass that with a .22u film cap

– Replace r117 and r118 with 22ohm metal film resistors
– Replace r101 and r104 with 1k metal film resistors
– Replace r103 and r106 with 7.5k metal film resistors
– Replace r102 and r105 with 10k metal film resistors
– Replace r107 and r113 with 2k metal film resistors

IC Control Voltage (Optional) MoD: Turns this compressor into a beast.
– Replace chips OA8, OA9 and OA10 with gold plated ic socket and a better ic like a LT1124 or LME49860NA.