Contact: pbecker@gmu.edu

If you own a VOX VT series combo amp (VT15, VT30, VT50, VT100), then you already know how great these amps sound! However there is a problem with the control of these amps during live performance. If you use the optional VFS5 footswitch to access the 8 user-defined presets during live performance, then you lose the capability to control the tap-temp and effects bypass functions with your foot. This was a major problem for me, especially since the number of user presets is so small, which means that you don't have the memory to save effected and non-effected versions of the same tone.

I have developed a DIY footswitch mod kit for VOX VT amps that allows you to turn the effects bypass on and off and control the tap-tempo function via a small floorbox! This allows you to use the VFS5 footswitch to change the user preset, while still having complete control over the effects bypass and tap-tempo functions. I have installed this mod on my VT100 and it's great! No matter what mode the amp is in, the floorbox gives you full-time dedicated control over the tap tempo and effects bypass functions. Using the footswitches on the floorbox is equivalent to pressing the corresponding top-panel buttons. The mod does NOT disable the top-panel buttons and they can be used at any time too!

This is a professional-grade installation based on an isolated dual-relay control system with 9-volt phantom power. The AC adapter (included) is installed inside the amp chassis, along with the relay box, so there is no wall wart. The 8' control cable is heavy-duty, with a durable PVC jacket rated at 300 volts. The footswitches are heavy duty, and the floorbox is extremely durable ABS plastic (metal enclosures are also available). The kit utilizes a robust grounding system so there is absolutely no noise or hum introduced by this mod. No drilling is required and therefore the factory warranty is still in effect, although the mod would have to be removed if warranty service is needed. Basic soldering skills are required to install the kit.

There are 3 purchase/installation options as explained below:

• I will build you a complete AC-powered relay control kit including phantom power provided by a 9-volt AC adapter for $129 including free shipping inside the US. Includes detailed instructions and hi-res photos so that you can install the mod yourself in your VT series amp. NOTE: I can only ship the AC-powered kit inside the US due to potential problems with the local electrical specs in other countries.
• I will build you a battery-powered relay control kit for $109 including free shipping inside the US. Includes detailed instructions and hi-res photos so that you can install the mod in your amp.
• I will install the AC-powered footswitch mod in your VT series amp for $199 (all parts and labor included). You can drop off the amp with me, or ship me the chassis only. Return shipping is an extra charge.

When the amp is plugged in and the phantom power toggle switch is turned on, the green LED glows on the external floorbox, located at the end of 8' of heavy-duty 7-conductor control cable. When you shut off the phantom power via the toggle, you can hear the "click" of the little relays switching off, which is kinda cool.

Here's how the system works:

• The Green LED on the floorbox is lit whenever the 9 volt power is on.
• The left footswitch controls the tap-tempo function. The Yellow LED flashes when this switch is pushed to confirm action.
• The right footwitch controls the effects bypass function. The Red LED flashes when this switch is pushed to confirm action.
• When the 9 volt power is off, the tap tempo and bypass functions are controlled by the panel switches only.

Note that the Red and Yellow LED's on the floorbox do not indicate the status of the effects bypass or the tap-tempo, they only flash momentarily to indicate that the corresponding footswitch has been pressed. It was designed this way to keep the internal installation as simple as possible.

The mod requires NO DRILLING of either the amp chassis or the cabinet.

The mod is REVERSIBLE if desired.

Payments can be made via either PayPal to pbecker@gmu.edu, or via an Ebay purchase if preferred.

I offer a 7-day return period, with refund of full purchase price, contingent on the condition of the kit when I receive it.

If VOX warranty service is required, the footswitch mod must be removed before servicing.

I can only ship the AC-powered kit inside the US due to potential problems with the local electrical specs in other countries.

Contact: pbecker@gmu.edu

CLICK PHOTOS FOR LARGER VIEWS

Stock VT100 amp chassis:
VT100 chassis with relay kit installed:
Modded VT100 chassis with relay box open:
Floorbox closeup:
Floorbox control functions:
Modded VT100:
Modded VT100: