Guide to getting and playing better gigs
Amp Myths
"My 100-watt amp is twice as loud as your 50-watt amp". This is one of those really sad myths that just won't go away in spite of volumes of mathematically proven, unambiguous, clear, undisputed, scientific knowledge to the contrary – knowledge that every tech worthy of a soldering iron learned very early in their training. Music store sales staff on commission love this myth because it's sold thousands of 100-watt stacks (not to mention the follow-on sales of expensive replacement tube sets). Here are the facts:
All other things being equal, a 100-watt amp will be just perceptibly louder than a 50-watt amp. It takes about a ten-fold increase in power to double perceived volume. You'd need a 500-watt amp to be "twice as loud" as your mate's 50-watt amp. Even more thought-provoking is the fact that a 50-watt amp will only be perceived as a little bit louder than a 15-watt amp driving the same cabinet!
All other things are almost never equal. There are so many variables controlling sound pressure level (SPL) and perceived volume that it's quite common for a small amp to sound louder than a much more powerful amp. Cab design, speaker size and efficiency, signal compression, and several other factors have far greater impact on perceived volume than power level.
"I need a 100-watt amp because my band has started gigging in clubs". This is a myth that probably originates with hormonally imbalanced teens who have more experience watching movies about teen bands than they have playing real gigs. Unfortunately, it's a self-perpetuating myth because the rhythm player is going to get a big amp because he's being drowned out by the lead player, then the bass has to get a 400 watt amp to be heard at all, then they need a 1200 watt PA system so that the vocals have some chance of being heard over the cacophony from the guitars and bass, and finally they end up having to mic the drummer even in a small club because the drummer is breaking sticks and skins and still can't be heard over the racket. Within a few years their hearing has been permanently damaged and they all decide that they need bigger amps!Three-quarters deaf, they finally make the big time and the guitar magazines write about the gang of three 100-watt stacks that the guitar hero uses on stage and all the wannabees have just gotta have the same rig. As you can imagine, this is another myth that sales staff on commission are in no hurry to debunk! Well, here are the facts.
There's absolutely no venue that requires a larger amp and cabinet than one suitable for use as a stage monitor – provided that the members of the band don't get into a juvenile competition to outdo each other. Need more feedback? Fine, move closer to the amp, for crying out loud! Typically, a really good 30-watt rig with a suitable cab is ample!Depending on the composition of your band and the variety of venues you play, an even smaller rig miked to the PA and then pumped to stage monitors may be even better. Note that while a good 30-watt rig has ample volume you may end up having to buy a more powerful rig to get other desired features.
At a small venue, a 15 to 30 watt amp can be placed behind the band in a traditional position and used without a mic. In this position the rig serves as a monitor for the guitarist and as the primary amplification for the guitar.
At a medium venue, the small rig can be placed in front of and facing the guitarist as a monitor, and be miked and run through the band's PA. The band's PA speakers are placed along the front of the stage and facing out. This arrangement allows the sound to be balanced at the mixer and allows the band to flood a medium to large venue without damaging their hearing.
At a large to giant venue, that same small rig can be arranged much as described above but now the band's mixer feeds the house PA. This is the only way to reach the back of the room without dangerous SPLs near the stage at a large venue and would be required no matter how powerful a rig the guitarist has.
Smaller equipment takes up less space on cramped stages. The money you save by purchasing a smaller amp can fund a nice power conditioner to protect your equipment and clean up powerline noise – the conditioner will cost less too since now you don't need one that will handle a billion watts.
If the band members will agree not to compete, all of them can recognize significant savings by not having to purchase unnecessary equipment. Your band is far more likely to be called back for a repeat engagement if you provide a well-balanced, easily managed performance than if you're just obnoxiously and uncontrollably loud.
Many guitarists already have the monster amp – it isn't necessary to get rid of it. You can use an attenuator and perhaps a smaller cab.
"I need a small combo because I live in a flat". This is sort of the opposite of myth two, above, and is closely related to myth one, above. While a small combo will certainly take up less room, it may or may not be easier to get good cranked tone out of it at bedroom levels. First, read myth one again. If it's true that we have to increase power ten times to double perceived volume, then it's also true that we have to reduce power ten times to cut the perceived volume in half. Thus, even a tiny 5-watt single ended tube amp is going to sound about half as loud as a fifty-watt stack (actually, it will be a bit quieter than that because it's probably driving an eight or ten inch speaker instead of a 4X12 cab). Even that five-watt amp will be way too loud to run cranked in a bedroom unless your neighbours are very tolerant. Here are some facts you should consider:
Even a 5-watt tube amp with an eight inch speaker is very loud by the time you crank it into distortion. You can use an attenuator with either a large amp or a small combo. Keep in mind, however, that attenuating below about 1 watt per speaker starts to adversely affect tone – it seems that a certain amount of speaker drive is required to round out distortion. Even one watt into an 8" or 10" guitar speaker is likely to get you evicted.
Many small combos do not offer a master volume, thus making it impossible to even get preamp saturation at acceptable volume levels. To get true "cranked tube tone" in a flat at lease-safe levels you're almost certainly going to have to use a combination of attenuation and a sound-proof speaker isolation box with a microphone running to a mixer or stereo. This is true whether you're running a 5-watt, single-ended, class A combo with an eight-inch speaker or a 100-watt stack with a 4X12 cab.
It's not a good idea to run an amp inside a sound-proof box, so even with a small combo you'll need an extension speaker. It's not much fun to try to enclose a 4X12 cab, so you'll also need an extension speaker with that kind of rig.
The lesson here, once again, is to select amps based on features, not on power level. A tiny five-watt class-A amp with an eight-inch speaker and no features may not be very satisfying after a while, will be wholly inadequate for gigging, and still isn't quiet enough to run cranked in your bedroom! Add a few features such as footswitchable channels, master volume, and an effects loop and that 5-watt amp starts to become pretty attractive!
"My tube amp has a master volume control that lets me get power-amp distortion at low volume levels". Yet another myth that sales staff love (seems like there are quite a few of these). The facts are:
With the possible exception of some very rare and expensive "boutique" amps, a so-called master volume does not reduce power output after the power-amplification stage as the name would seem to imply. The master volume controls found on popular amps cut the power between the final preamp stage and the power amp. In all popular tube amps, when you turn down the master volume, then turn up the gain controls to achieve overdrive, you're overdriving the preamp stages, not the power stage.
The "master volume" control permits running the preamp at full saturation or beyond at reasonable volume levels and allows you to balance preamp and power amp saturation for a wide variety of sounds.