Goodwood Audio TX Underfacer Junction Box

With a master mute button, two different summing modes, and a myriad of inputs and outputs, this under-pedalboard junction box is your one-stop i/o solution!

The Goodwood Audio TX Underfacer is like The TX Interfacer but designed to go under an angled pedal board. Use Underfacer to take care of all your input, muting, tuning, summing, isolating and phase correcting needs without using any pedalboard real-estate.

Master Mute
Hit the mute pushbutton on The TX Underfacer to mute your signal before it reaches your amps. No matter what craziness is happening on your board, the master mute has the final say on what does or doesn't get sent to your amp.
You can also control the master mute with RMT remotely on top of your pedal board! Just get RMT and a TRS cable.

The TX Underfacer has two types of summing: Stereo Sum and Split Sum. To access these two modes, use the internal DIP switch to select which mode is best for you.
- Stereo Sum: This is the default mode The TX Underfacer ships with. In this mode use stereo effects as normal. When summed, the left and right inputs are merged and a duplicate mono signal is sent to the left and right outputs. This option can cause cancellation with some modulation effects but works great for delay and reverb.
- Split sum: Still use stereo effects as normal. When summed, the right input is ignored and the left input is split to both left and right outputs. This option does not cause cancellation with modulation and can also be used with a mono signal to split it to two amps (left input to both left and right outputs)

RMT can be used with The TX Underfacer to access the summing mode read more and master mute.
- Summing: Hold the foot switch on RMT for more than 2 seconds to switch the sum state to stereo or dual mono. The LED on RMT will blink rapidly once the change has been made.
- Master Mute: To mute or un-mute your signal on The TX Underfacer using RMT, tap the foot switch. Yup. Easy.

Ground Lift & Phase Correction
The TX Underfacer comes with ground lift and phase correction for players that want to run more than one amp.
- Ground Lift: Sometimes when running two amps it's possible to get a ground loop - a nasty buzz when your two amps are at different ground potentials. To safely eliminate this buzz you need to lift the ground on one amp with an audio transformer. Do this by pushing the TX pushbutton in.
- Phase Correction: If your two amps are out of phase (sounding a bit honky and a noticeable loss of bottom end when both amps are running) you can correct this by pushing the TX and 180 pushbuttons in.

Input & Buffers
The TX Underfacer comes with a few different buffers. Firstly, the input is buffered. This means before your guitar sees the first pedal on your board you are buffering the signal to your pedals, preserving your guitar tone. It also comes with an always-on tuner out so you can get immediate feedback from your tuner.

The TX Underfacer also buffers the Left and Right outputs which send signal to your amp. Long cable runs are not a problem for the ultra-high headroom buffers on Underfacer.


- Use for any Input, muting, tuning, summing, isolating and phase correcting needs
- Designed to go under an angled pedal board
- Mute your signal before it reaches your amps
- Control the master mute remotely on top of your board with associated RMT pedal
- Has Stereo Sum and Split Sum Summing options
- Input and Output buffers
- Ground lift and phase correction to cleanly run more than one amp
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- Inputs: Buffered In, Left and Right In
- Outputs: Send to board, tuner out, Left and Right out
- Input Impedance (Brd, Left and Right): 1M
- Output Impedance (Tuner, Brd, Left, Right): Very low
- Control Input: RMT Jack for external mute and summing
- Power Requirements: 9V center negative 2.1mm barrel.
- Current Draw: 150mA
- Dimensions (incl. all jacks and switches): 102mm wide x 120mm deep x 36mm high
- Weight: 320 grams
Dimensions and Weight in Packaging
Base Item
Shipping Weight: 0.85 lbs
Shipping Dimensions: 6 x 5 x 2 in
Manufacturer Part Number (MPN): The TX Underfacer


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