The M-Audio Keystation 61es makes an ideal keybed donor for a low-cost VPO keyboard stack. Included in the price is a discrete 61 key semi-weighted keybed, MIDI controller, that supports continuous control, and cables. The goal of this article is to provide enough information for a moderately practical person to create an AGO compliant, 2 manual MIDI keystack for less than £400. We are donating this information to the public domain as we no longer produce keyboards based on re-skinned MIDI controller keyboards.

Instructions Below.

First task is to liberate the keybed from its plastic case. Place the keyboard, keys facing down, and remove all of the screws on the rear of the case. Keep them, they'll be needed later. Carefully turn the keyboard the right way up and remove the top case, you'll need to unplug the volume slider, pitch bend and switch/LED board cables from the MIDI controller. Unscrew the switch/LED board and the volume slider from the top. The pitch bend board in the top is not needed. Unplug the keybed ribbon cable and earth wire from the MIDI controller and remove the keybed. Unscrew and remove the MIDI controller. The switch/LED board needs to be kept as it is the only way to change MIDI channel. The volume slider cable and connector will be used later to connect the swell pedal.

The keybed natural keys need to be modified in order to achieve an AGO compliant offset by removing the waterfall front. This is a simple but laborious task requiring a small, flat-blade screwdriver, a hacksaw and a file. If pistons aren't going to be fitted to the great manual, only the swell keys need modifying. Each natural key is removed by removing the return spring and, using a small screwdriver, unclipping the key as shown below. The majority of the waterfall is then cut off using a hacksaw, the remainder with a file.

Here's a very basic drawing of the keyboard stack. It details transverse and longitudinal sections. All dimensions are mm. Do not scale. Please ask if any dimension is not clear.

The woodwork is quite straightforward. Start with the key cheeks. These can be made out of any wood however oak is preferred (pine in the pictures). They can be any width within reason (30mm in drawing) but must be 64mm tall. Lengths are specified in the drawing. If you have a router, a rebate (rabbet) bit can be used to cut a rebate in the cheeks to accept the 9mm ply keybed bases. If you don't have a router, the bases can be attached to the cheeks using 15mm x 15mm aluminium angle. The overall width of the keybed base is determined by the attachment method and the size of the the router bit. The goal is to achieve 3mm clearance between each cheek and the keyboard outer edge.

Before the cheeks are finally attached to the base, holes need to be drilled to accept the keybed mounting screws. The best way to do this is to place the keybed on the ply base. Using a square, position the keybed so the front of the keyboard (the lip on the very front of the natural keys) is 31mm forward of the front edge of the base. Then centralise the keybed on the base. Mark the position of the mounting posts on the base and drill and countersink 5mm holes.

Temporarily screw the keybeds to their bases and offer up the cheeks. The top and front of the cheeks should be 3mm from the top and front of the natural keys and there should be 3mm clearance between the outer keys and the inner face of the cheeks. Adjust where necessary and finally attach the cheeks. It may be necessary to pack up the keybed with washers or file down the mounting post to achieve the 3mm top clearance. This is aesthetically important. It also may be necessary to file the side of the plastic keybed chassis if it fouls the cheeks. Stack the keybeds to ensure that the swell and great cheeks align.

The piston rails are made from 4mm ply (or any 4mm strip). Cut them to a depth of 35mm and a length to fit between the cheeks. Drill them in order to accommodate your pistons and fix them to the keybed bases using countersunk screws. The depth of the rail may need to be reduced if the keys hit on full travel. Clearance between piston switch and keybed base is minimal. Measure twice, cut/drill once!

Make a top cover plate as per the drawing and fabricate a music desk to your own needs.

A rear cover plate can be made from 18g aluminium plate. It can be drilled to accept a 1/4" stereo jack for a swell pedal and power connector.

A standard 10K ohm expression pedal such as the Yamaha FC-7 can be used as a swell pedal. Don't try and plug it into the sustain pedal socket! Cut the cable from the volume slider and solder it to a 6.35mm Stereo Chassis Socket (Maplin) as follows.

Tip ----> red crosses
Ring ----> white
Sleeve ----> red dashes

The above information is given in good faith with no guarantee. If you spot an error please let me know and I'll rectify it as soon as possible. Thanks!