Tube Fx Loop Board

Tube Effects Loop


This series Fx Loop utilizes a 6N17B sub-miniature military-grade, dual-triode vacuum tube with Dumble style Local Negative Feedback for low distortion, flat frequency response and tonal transparency. It employs high voltage, has zero-loss, is built on a PCB and includes an optional true-bypass switch.
This all tube FX loop add-on module can be fitted to virtually any guitar tube amplifier.

The FX loop is optimized for insertion between preamp and driver stages, the low noise, non-clipping, analog effects loop is designed with a cathode-follower send stage and a return gain stage both of which can be adjusted.

The mounting requirements are simple (Power, Ground, Signal In, Signal Out, 2 heater wires) and it is held in place by chassis mounting the ¼” jacks.

Power drain on the B+ is minimal as the unit features a voltage regulator to minimize noise and simplify installation. This eliminated the need for a voltage dropping resistor. Similarly, heater current draw is minimal. The 2 internal trim (level) pots that can be accessed directly through the jacks (no chassis removal) or internally by using a small flat-bladed screwdriver.

The PCB footprint is small (3 holes), yet both the send and return levels, spaced at 1.5″, can be adjusted for nearly any loop requirement. Low cost stomp boxes and pedals work just as well as thousand-dollar rackmount effect units.
The Send is configured as non-interrupt, so it can be used as a Preamp/Slave Line Out and Return can be used as Power Amp in.  When no connection is made, the unit accurately passes signal but there is also an optional panel mounted true bypass switch.
This FX loop kit makes inserting any effect or pedal, less intrusive to the tone of your amp.

Kit includes all cables and wires plus detailed instructions and also detailed layouts for selected Trinity Amps products.

Pricing Options

Canadian Customers Click 'Inquire' to receive up-to-date CAD pricing and shipping. Include postal code for quote.
We price affordably while managing fluctuating exchange rates with our suppliers. Our CAD best price guarantee accurately reflects our costs.
Tube Fx kit
$118 USD
Tube Fx Loop with 6N17B sub-miniature, dual-triode vacuum tube.

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All prices are listed in US dollars. Orders ship from Brighton, Ontario, Canada, applicable taxes not included. Specifications and prices subject to change without notice.

Trinity Amps Inc.
165 Kanata Dr.
Grafton, ON
K0K 2G0

+1-905-373-6571 Canada, EST