Features

• Full bypass with fully-balanced hot/cold switching. Fully passive.
• Two Inserts with Flip.
• Backbone signal flows through the connections on the left to the right.
• Insert connections are on a 25 pin D Female in a modified Tascam format.
• AES Tascam-format DB-25 breakout cables from Hosa (AES-803T), Mogami (GOLD AES TD DB25 XLR-03), Planet Waves and others may be used. (To use AES cables with the Insert Switcher the male and female XLR breakout connectors need to be reversed.) Planet Waves uses male-to-male extension cables, an unterminated female D breakout cable, or a terminated D breakout cable. To use only a Planet Waves breakout a DB-25 male-to-male adapter is required.
• Normal signal flow is Left/Right In > Insert 1 > Insert 2 > Left/Right Out.
• Flipped signal flow is Left/Right In > Insert 2 > Insert 1 > Left/Right Out.
• Cascadable using additional boards in series for more backbone inserts.
• Configurable as an three Input Selector using the backbone and return inputs.
• Sealed low signal current relays.
• Relays can be socketed to make them user-replaceable.
• No logic required: Uses sustained/latching SPST push button or toggle switches.
• LED outputs. (Current-limited to 10 mA; 24V/2K21Ω.)
• Isolated audio, relay and chassis grounds.
• Series-parallel coil connections reduce power consumption and heat.
• Relay coils are 12V, control supply is 24V.
• Can be powered from low-cost 24V switching supplies.

Mechanical and Power Specifications

• Board Size: 3.8" x 2.75"
• Mounting holes: M3 0.125" diameter on a 3.5" x 2.45" pattern.
• Assembled Board Size: Height: 0.7"; Depth with DB-25 Connector 4.0" overall, 3.8" depth behind panel. With 3/8" spacers and washers installed the vertical center line of the DB-25F connector is 0.75" above the chassis bottom.
• Power Requirements: Coil current using Omron G5V-2-H1-DC12 relays, 14 relays and 3 LEDs on, 120 mA typical 2.82 W. Low sensitivity relays are not recommended as they consume 7.7 W under similar conditions.
• Connectors: Power In/Out (2 pin Phoenix X2); Backbone In (6 pin Phoenix); Backbone Out (6 pin Phoenix); Insert Send/Returns DB-25F; Switch/LED (12 pin Phoenix).

The construction thread for the Insert Switcher including, schematics, bill-of-materials and other information is in the Pro Audio Design Forum.