Drip Opto 4

Drip Electronics proudly releases the next level in LA style optical compression:
The new OPTO 4 printed circuit board this special edition pcb has been designed for the many who have requested a higher performance pcb in the OPTO line. On a design level, we have pulled out all the stops, from a larger format pcb /gold plating and red solder mask. The new Version 4 incorporates the highly effective design of the Opto 3, and has been updated with several new features, including the use of Dual T4B optical cells. This new feature allows selection between a fast release t4 or a slow release t4 - a perfect option to better match compression styles for different types of source material.

Another feature is the new full star ground structure. Each resistor and capacitor in the amplifier section is given its own return path to a perfect star to keep unwanted noise and hum from being injected into the amplifier. To protect the pcb’s lifespan and allow the use of high-end solder, we have chosen gold plating (ENIG) for the finish.

The noise floor on the opto 4 is very low and is comparable to its point to point counterparts. Designed around the same concept as the vintage model, the power section also incorporates the use of large format axial filtering capacitors. This unique upgrade allows the use of capacitors by mundorf / jensen / CDE / or sprague. All offer superior ripple rejection and performance over the tiny radial caps found in most production compressors.

Price: $150.00

Purchase the Opto 4 at the Drip Store
Opto 4 Photo Gallery

Specifications

• the pcb has been designed around the circuit and not the components. Creating the shortest paths to each important connection
• pcb uses 3 oz copper
• a new ground plane has been added using the heaviest gauge of copper possible. (ground scheme still follows the original design separating the reduction/audio/input transformer circuits.) (also aids in shielding the audio circuit below it)
• the use OF SPRAGUE ATOMS or equivalent filtering electrolytic capacitors
• use of pcb mount 1 meg potentiometers for stereo adj/lim response and optionally zero adjust, thus eliminating additional wire runs
• pcb is .93"thick
• pcb is silver plated
• tube heaters have dc reference circuit built into board (Further protecting ac hum from entering the audio circuit)
• a grid resistor has been added for the 12ax7 in the amp section
• an extra 1k resistor has been added to the Pi filter in the power supply
• the diode footprints are now made for fred/hex diodes (to-220)
• quench arc snubber has been added on board for the power switch (to control popping noise on power down)
• 68 pf cap has been added in parallel to r11 to help prevent occilations
• 2nd pad connected to ground has been added for connecting gain 2 and reduction 2 (giving option to omit 'y' cablewhen connecting potentiometers)
• x-cap has been added to the primary of the transformer (hf noise filter )
• resistor footprints are large enough for carbon comp
• capacitors foot prints in the amp section are made for poly-pro caps
• option to select ground circuit for the output transformer (into audio gnd or reduction gnd)
• most trances are 2mm wide on 3 oz copper (almost 20 times the needed copper)
• Entirely new design of circuit balancing a compact Design but ensuring separation between traces
• pcb mount sowter transformers
• Optional grounding through standoffs
• heater traces moved to bottom of board
• entire circuit on one side of board (no overlapped traces)
• grid resistors for 12bh7a
• Insulated 5.08 screw connectors can be used for all connections
• Circuit is true to the original 1960's design
• insulated 5.08 screw connectors can be used for all connections
• heater traces on board (no heater wiring)