Affective Rack Setups

-The article Reducing Hum covers lots of topics which are important. Please read that article as well.

The whole subject of tone, sound, quality, etc is very subjective. I try to take in account how a setup sounds when performing and recording in a band situation. Some gear sounds amazing when you play alone, but is useless in a band situation. In my opinion a good sounding setup interacts to your playing and is able to create various sounds that will stand out in the mix. The character of the guitar shines through, individual notes can be picked out, even at high gain sounds, and should be pleasant to listen to. Great articulation and attack are a must.

Lotís of people think rack setups donít sound as organic as a traditional tube amp. Although this may be the case in some situations, the fact gear is rack mounted doesnít have to influence the organic character of a good amp. The only "problem" is to use the right gear. Most ads for rack gear promise that it can do it all and sound as good as the best. Unfortunately a lot of them sound far from great. And although modeling amps are getting better, they still donít sound as good as a good tube amplifier.

For years I used a tube multifx/preamp unit connected to a tube poweramp. I always thought the preamp sounded pretty good. Until I had some money to spend and bought an all tube preamp. The difference was huge. With just one sound from the tube preamp I could play everything I did before and sound even better, although before I needed a dozen presets. From then on I realized how important a good sound is and that no fx unit can make a mediocre preamp sound great. Therefor the best advice I can give anyone is to make sure you have a good sounding (tube) preamp and poweramp. Together with your guitar, speakers and your fingers they create your sound, your tone.

Unfortunately a lot of rack users pay more for their fx devices then their preamp and poweramp. No matter how cool your fx are, they can not compensate for a mediocre amp sound. I can not emphasize this enough. Unless you are 100% sure you have an amp section which is the crŤme de la crŤme, please read this paragraph again and again.

Besides a good amp section, where does an affective rack setup consist of? Well you can make it as extensive as you like. Generally I would say an affective rack would have the following:
* preamp
* poweramp
* power supply
* tuner
* effects
* (mixer/switcher for fx)
* good midi controller
* quality 19" rack
* good cabling

Try to figure out what you want. The sound, possibilities, size, budget, etc. Start working out the idea, begin with the preamp, next the poweramp and add on from there. Set priorities and goals. Normally it takes up quite a while before you have a killer rig. Mainly because most killer rigs cost a lot of money when done right and sometimes the desired units are hard to find.

There are only a few fx devices that do not affect your dry tone, which is really important if you want to keep your sound and dynamics alive. Therefor itís recommend to use a form of switching/mixing device. They can either mix your dry and wet signals and/or keep the unused units out of the signalline. The DMC/VoodooLabs unit seems to be very popular, just like the stuff from Axess Electronics and Custom Audio Electronics gear is very nice if you can spend the money. For ultimate flexibility the Sound Sculpture Switchblade is a good solution.

Some people say rack setups sound a bit stiff, not as organic or dynamic as a combo for example. With many setups this is the case. There are several reasons for this. If you expect your programmable preamp and solid state poweramp to sound as good as a Fender Twin or a Marshall Plexi, you need to think twice. In most cases they donít even come close. There are maybe only a dozen different preamps that are able to sound as good (or even better) as a high quality amp. With most rackmounted gear the designers have spent more time and effort to get a wide variaty of sounds (at low costs), instead of searching for an amazing high quality sound. Even if you have high quality gear, a rack setup can respond differently.

First and foremost most rackmounted poweramps have more power (watt) then a single head or combo and therefor more headroom. Therefor the point at which the amp starts to break up, which is its sweet spot, is at a higher volume level. 2nd most racks use digital fx instead of stompboxes. The AD/DA converters can cause loss of dynamics and transparency, especially when the fx are placed in series between the preamp and poweramp.

Last but not least, the volume settings of the preamp and poweramp may have an influence on the dynamics and tone, depending on their design. In my experience most setup sound better with the volume of the poweramp turned up, somewhere between 7 and 10. The volume of the preamp needs to be cut in most cases, to keep it at reasonable dB levels. This will not give you poweramp saturation, because for that you would need a hot preamp signal as well, but the poweramp tubes just respond better. Gives a more defined sound with better articulation, attack and larger sound stage. If you keep the volume of the poweramp low and boost the output of the preamp chances are high you are overdriving the input circuit and/or phase inverters of the poweramp. Which will give you a more harsh and compressed sound which doesnít attribute to a more dynamic and organic sound. Of course every poweramp should be well biased and retubed to get the best possible sound. No matter what the manufacturer says.

How to set it up?
First you would have to make your choice of equipment. Using independent units for chorus, reverb and delay fx can make a setup a lot more complicated and can attribute to more noise and loss of signal quality. There are a couple of very well designed fx devices that can produce the most needed fx. Itís worth saving money for one good unit, then to spend cash on several independent units, each of mediocre quality. A combination of a Rockman Chorus, Lexicon Alex reverb unit, a Rocktron noisegate and a Boss delay may be a friendly choice for your wallet, but for your sound it would be a lot wiser to spend the money on a device such as the TC Electronic G-Major. This will give you a higher sound quality, less signal loss, easier to work with and more options.

The placement of devices in a rack is very important. A rack should be in balance, not top heavy and should leave enough room for ventilation. General rule is to keep the heavier gear at the bottom and the lighter gear at the top. Try to setup it up so you have a clear view of whatís where and how itís connected to each other. Tube amps can create a lot of heat, which not all device like. Leaving one blank space above the poweramp is a good idea. If this is not possible, place a unit above it which can withstand the heat and are well isolated against interference.

Before you install everything make sure you have all the gear you need at hand. Always make cables at custom lengths and take good care in installing the units. Use (shoulder) washers to prevent scratches at the front of the units from the screws. Make sure the units are not in contact with each other, or at least do not conduct. For this you will need a multimeter. To prevent groundloops check the Reducing Hum article.

An affective rack setup is well organized. All gear is screwed tightly with at least 4 screws to the rackrails. If only 2 screws can be applied, use the bottom two holes or on one side the bottom and on the other side the top one. Cables are neatly worked away and audio and mains cables are kept separate. Adapters, stompboxes, etc are fastened and nothing inside the rack can move. Buy some feet of bare microphone cable with excellent shielding and enough connectors and make your own custom cables (see Reducing Hum article).

Some people want to use more then one preamp at once. Simply splitting the signal can cause hum. Sometimes an active splitter will work, in all cases an audio transformer will solve the problem. Of course high quality trafoís are recommended, Lundahl for example. In many cases running two or more (pre)amps at once will sound horrible. This is caused by the difference in phase. Most common is a difference of 180 degrees in phase, which can be easily solved by inverting the phase. For this you can use an audio transformer or a opamp/fet design, which you can make yourself. Sometimes using a different output (such as rec outs, fx sends, headphone outs, etc) can change the phase and solve your trouble. The difference in phase (in or out-of-phase) may not be the same for all channels. So maybe the clean is in phase while the high gain is out of phase.

If one of the preamps has an AD/DA converter a slight delay of the audio signal will occur. This can generate strange phasing problems and canít really be solved easily.

It goes without saying that taking good care of you gear is necessary. This means that you have to handle it with care, install and connect it properly and leave enough space for ventilation. Donít close your rack doors direct after using it, but give it some time to cool off and ventilate. Donít expose it to moist, dust or heavy vibrations. Placing a (smaller) rack on top of a speaker cab is not such a good idea. Most 19" units are full of electronics, some of which are not soldered or hard mounted, so they can shake loose. The tubes are not always as sturdy mounted as with normal amps, so be gentle.

Transportation is another point to look at. Itís no problem to move your gear around in a car/van/etc. But prevent it from too much vibrations or even shocks. The rack should not move when you drive over a speed bump. If it does, replace it. Many rack users have a cable snake running from their rack to their pedalboard. Itís important that the snake, if it stays inside the rack, itís held tightly inside and canít move. Loose cables (and connectors) can cause serious damage to your gear (and tubes) when they can move inside your rack. So make sure they are either not present in your rack when moving, or they are firmly held together some way.

Poweramp tubes should be matched and the amp biased every time they are replaced. Yes even if you have an amp with a fixed bias (such as Mesa/Boogie) itís wise to get it biased, this can greatly enhance the sound of your amp. Itís the engine of your amp, how does your car drive when itís never been checked or adjusted?

If everything is well installed and the rack isnít exposed to too much violence, everything should work fine for a long time. But before each check if all cables are still connected right, if all units get their power and respond to midi and channel changes. This can be done in a matter of seconds, but prevents lots of trouble during a gig or recording session.

Most programmable gear have a battery inside to store your patches when the unit is not used. These batteries normally last about 10 years. To prevent loosing your patches itís a good idea to change the batteries every couple of years.