Keyboard Magazine "In The Studio"
Article # 30
Rack Mounting Your Gear
This month's column is a guide to better rack mounted gear. I put together some basic rules of thumb for making you rack mounted gear smile.
Choosing the Right Rack When buying a rack, don't just figure out how many spaces your gear will take and then buy that size rack. This is a mistake that will cost you plenty when you quickly out grow your available rack space. Most people soon wind up with enough gear to fill a 4ft 19" rack or about 26-30 spaces. What is a space? A space equals 1.75". A Yamaha TX81Z is one space unit. An Akai S-900 is a three space unit.
Choose the right grade of case for your application. If you are looking for a rack case for the road, I recommend a shock mounted case. This is a case within a case. The inner case is a standard 19" rack case but it is surrounded by foam from the outer case. This type of case can insure that your gear will work after it has been unloaded off the truck, of course it is much more expensive. Companies such as Anvil, Calzone and others charge between $350.00 and $600.00. This may seem expensive but remember no insurance policy can help you replace broken gear immediately on the road so go for the better case. If your gear will stay mostly in your home studio, choose an all metal rack. There are low priced units by Hammond and better units by Premier. They can range from $200.00 to $450.00. Since they are metal they are better suited for shielding from RF interference.
Look to see that your rack will have rear 19" rack mounting rails as well. This will enable you to mount other gear, fans, power conditioners, outlet strips and etc. on the rear of the rack.
If you are buying a large 4ft rack, keep in mind that wheels are a must! This is true for the road or in the studio. Remember there will come a time when during a session that you will have to trouble shoot something behind the rack.
If you are your own rad, choosing multiple racks. Splitting up your gear can save the family jewels. Playing a gig with stair cases involved is all it takes. The only downfall is having everything permanently hooked up. I'll explain later about making a harness to simplify the setup.
Keeping it Cool The biggest mistake most people make when setting their rack up is putting all the gear in the rack with no thought given to ventilation. Make sure the back of the rack is as open as possible. Leave at least one space between heavy heat producing gear (i.e. between a Yamaha TX816 Rack and an Akai S-900 sampler). Use fans for better results. If you are on stage and noise is not a problem, have exhaust fans mounted at the top of the rear of your rack. Have them mounted in a standard 19" rack panel. Make sure the fans blow the air out of the rack, not into it. For an extra cooling boost, install fans at the bottom of the rack that blow air into the rack. Then close up all the empty spaces on the back of the rack with empty 19" rack filler panels. These empty panels come in all sizes from one space to five and seven space sizes. Also close up any open spaces on the front of the rack too for this double fan cooling technique.
Use Outlet Strips Install outlet strips in your rack so that all the gear can be plugged in ready to go. Look for an outlet strip that has a circuit breaker on it to protect your gear. Most outlet strips have 15 amp breakers on them. If your amp load exceeds 15 amps, use enough outlet strips to cover the load.
Power Conditioners and Power Stabilizers. Another elaborate but well worth it investment is adding a power conditioner to your rack. They are sold by the # of amps that they are rated at. Power conditioners can quiet noisy AC lines in most situations although they are not a cure all. If you play out in clubs and large halls to large auditoriums, a power conditioner will prevent power spikes and transients from damaging your gear. Many a bank of synthesizer patches have been lost to a lighting storm while on stage. There are more expensive power stabilizers that will keep the voltage at a desired 115 or 120 volts even during a brown out where the voltage can drop to 25 volts. This will insure that you will not have to reload your samples on stage in the middle of the show. Usually your power conditioner will be mounted on the rear of your rack at or near the bottom. See my past Keyboard article " Things that go Click, Pop and Buzz in the night" for more info on this subject.
Building your own Connector Panel. One way to make connecting your gear a snap is installing a connector panel on the rear of your rack. Buy a 5 or 7 space blank 19" panel. Install a balanced male cannon connector for each output and a few extras as spares on the panel. To solve difficult grounding schemes install a single throw single pole mini bat toggle switch above each male cannon connector. Wire the switch to intercept pin 1 on the cannon connector. In this way you can easily lift pin 1 for problem situations. Note* Make sure that each of the connector's pin 1 is not touching the chassis of the metal panel that they are mounted on. This could cause a severe ground loop. Companies such as Conquest sound make pre made panels with the connectors all mounted in many different configurations.
To go one step further, you can buy balancing transformers from a number of companies , such as Whirlwind, to build in your own balancing transformers. In the studio, balanced is better. On the road balanced is a must. Especially if your signal is traveling long distances to the console. Mount these transformers on the same panel as your cannon connectors. Note* Don't let the chassis of the transformers touch the ground of the panel. Use double-sticky tape to isolate and hold the transformers in place. The transformers should be place in the circuit between all unbalanced pieces of gear and the panel.
Make You Own Wiring Harness. If you've gone the route above and built a rear connector panel you might want to add multi-pin connectors to your panel as well. A multi-pin DL connector which comes in male and female (Thank God!) chassis mount configurations, can connect the equivalent of 24 cannon connectors. For stage setups the cost of wiring multi-pin connectors is justified by the amount of setup time they save.
Instal your DL connectors so that they are wired in parallel with your cannon connector panel. This way you have both and in an emergency there is an alternative way to hook things up.
You can make your own snakes to connect to the DL connectors. Use Connectronics multi-colored snake wire. It comes in 8 shielded pairs in a snake, colored coded for easy hookup. you can use three lengths for each DL connector. Install the opposite sex DL on the rack end and male cannons for the stage end to interface with most stage snake boxes. You could also have each end terminate in an balanced Bantam plug or build another snake for use in the studio. Male balanced Bantam plugs will patch directly into most professional consoles. So you can have the right snake for stage and studio.
Use a Midi Pacthbay Above install a Midi patchbay in your rack. Wire all the ins and outs of all your midi connections to the bay. If you set it up correctly and use good quality Midi cables, you should never have to go behind the rack to swap Midi cables again.
Grounding Tips This really deserves a full column in itself but, try this.. Plug all the gear in AC wise and then plug all the audio outputs into a mixer. Turn up the volume of the mixer so that you hear hiss. Note* Be careful. If you can hear hiss then the output is really loud! Listen selectively to each piece of gear in the rack. Try installing a third prong ground lift adapter on your noisy pieces of gear. Also you may have to ground certain pieces of gear to the chassis. This is true of some gear that does not have a third prong on the AC cord. Accomplish this by running a piece of monster cable from the rear of that piece of gear to the rack rails. Check that the rear connection you've made is actually ground for the unit.
There is no overall formula to cure ground hum and buzz. You'll just have to experiment. But once you've got, it will be great! Good Luck and happy racking Dudes...
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