The Perfect Sound Cart: Construction Details

The obvious approach is to use a large, flat shelf fitted with brackets designed to secure specific recorders. The purpose of those bent edges is two fold: they provide an attachment point for a protective cover on the top shelf and they stiffen the shelf. The shelves easily accommodate any of the field recorders in common use today and also provide extra room on the sides for cable connections. Chinhda ingeniously puzzled out brackets for each recorder to engage shoulder strap mounting points, rubber feet, and other attachment opportunities. He has bracket designs to secure the standard Nagra (IV, 4.2, and IV-S), the Nagra D, and the Fostex PD-4. He doesn’t have anything "off-the-shelf" to fit other recorders but pretty much any field recorder would provide some attachment point or irregular surface he could exploit.

The Cooper mixer presented a similar challenge. Fitting brackets to the handle mounting points was an obvious choice but securing the foot of the mixer was trickier. Chinhda ended up mounting a metal plate to the mixer using an existing screw and tapping the plate so a securing screw could lock the mixer down without being off-center.

If there's one component that really makes the cart work, it's the Lord mount shock absorbers. The Lord Corporation makes a wide variety of adhesives, vibration and shock control devices, and other ingenious solutions to construction challenges. The range extends from stabilizers for suspension bridges to disk drive components. They claim to have manufactured the engine mounts for the B29 Superfortress. The units we use appear to be designed for mounting avionics in airplanes.

We only use a handful of these shock absorbers so we've been getting them from an aero suplus shop rather than the manufacturer. For years we would visit Joe Factor Sales in Burbank and wander through aisles teeming with aircraft junk/treasures to supply our crafts projects. Regrettably, Joe died or retired but his daughter-in-law (I believe) purchased his inventory and has opened Luky's Hardware only a few blocks away.

Keeping the gear cushioned with these mounts allows the cart to stay assembled without risk to the equipment. In several years of use there has been no harm or alignment problem with any component kept on the cart on a shock mounted tray. Camera trucks have navigated dirt roads to movie ranches many times and the equipment has been well protected. Of course, we only rely on these mounts for local truck transit or travel to the set in a car. For long distance travel, we break down the gear and pack it in cases.

The "R2 Unit" serves the same funcition as a rolling chest of drawers in an auto repair shop. If size and weight were no object, we would have just gone shopping at Sears or Snap-On Tools. Building a service cart of shipping cases inherently preserves the possibility of shipping the whole business by air. Being able to separate the cases gives some flexibility in packing the car. (I hate SUVs and vans and I'm determined to find a way to work with smaller vehicles.)

This system covers my needs pretty well. In the near future I'll need to update the recorder brackets to secure a Deva or Sound Developments recorder or some other hard drive varient. But that's a minor adjustment. The basic cart is adaptable to evolving gear. I continue to look for a lightweight alternative to the steel rack drawers; they are responsible for more weight than any other component. But I don't see the need for any extensive changes for my work.

However, that doesn't mean that I don't see room for improvement. Starting from scratch, we could make this sort of cart with better and more extensive shock mounting, graphically distinct equipment platforms, split drawers, self-shipping capabilities, fitted dust and debris shields, built-in wiring harnesses, etc. And the whole business could be half the existing weight. The actual equipment we use is very small and light. Consider:

Cooper 106 mixer:	16 lb.
Fostex PD-4:	7 lb.
Deva II (or substitute your favorite):	5 lb.
4 Lectro 211 receivers @ 14 oz. each:	3.5 lb.
miscellaneous (video monitor, cell phone charger):	3 lb.
Comtek and IFB transmitters	3 lb.
coffee mug	1 lb.

There's less than 40 pounds of actual equipment on a well-supplied cart. These are only examples; if you prefer a Yamaha mixer or a Cameo, that could be easily accomodated without significantly changing the size and weight. True, a good battery supply probably doubles the weight but it still ought to be possible to assemble a working feature package that's only slightly more than 100 pounds with battery. With a little ingenuity we could fit the whole affair into a Miata! Well, maybe that's a bit enthusiastic but I think an Audi A4 wagon or a BMW 3-series wagon is possible.

Let me know if you're interested. It wouldn't be cheap but we could make an awesome cart if we built it from the ground up and incorporated all that we've learned from the previous ventures. At the rate gas prices are going up, you might pay for it in the reduced gas bills that come with ordinary cars. In the meantime, feel free to use our experience to make your own cart.