Re: Adding bass here soon to my collection...what to do..
That looks cool! I'll look at that for sure.
200w sounds crazy loud to me
I am not gigging anything above club/bar level. Usually with no drummer.
The head a cab idea looks expensive to me.
So 100w bass amp is not as powerful as a guitar amp?
100w is 100w, but 100w at 50Hz is different from 100w at 3kHz.
Forget what you know about wattage numbers from playing guitar. The instruments and amplifiers may look similar, but they do different jobs and so they have different design philosophies that make wattage ratings mean different things.
* Bass amps are intended to provide clean headroom, because you very rarely want distorted bass (and if you want it, there are pedals for it). Guitar amps are designed to run out of headroom fairly quickly, so they are typically run at higher power settings than they're actually rated for (the rating being their maximum clean gain).
* Bass frequencies take more power to produce from a traditional speaker cone than higher frequencies closer to the resonant peak.
* Humans perceive bass frequencies as being of lower volume than upper midrange frequencies of guitar tone, so to mix well bass amps need to produce a higher-pressure sound wave.
Remember that when talking about decibels of sound level, a small decibel increase requires a very big power increase to drive it. So, working with some round figures, a 100Hz sound requires 15dB higher sound level to sound the same volume as a 3kHz wave in the meat of a guitar's tone. You need to produce that from a speaker that might have a 6dB "disadvantage" at 100Hz relative to its resonant peak near 1kHz (and that penalty gets really big really quick as you get down to the 30-40Hz range of the open B and E strings), and you'll likely want to get to that volume with between 6-10dB of headroom before you start clipping your power amp (very bad for speakers to be fed a clipped signal from solid-state amps). Add it all up and you're talking about needing to have 30dB more power than a guitarist to sound as loud as he does cleanly. That's 3 orders of magnitude - 1000x the power - to have enough rig to sound as loud as a guitarist at your respective fundamental frequencies.
Luckily it's not really that bad. Just like a guitar, basses don't just produce their fundamental frequency, but a series of higher harmonics, so bass will be "present" in the mix far earlier as your power increases than the human equal-loudness curve will indicate. Still, you're going to want that headroom, between 3-6dB, to allow for note attacks, especially for slappers, and that right there is 2-4x the power rating of one guitarist's amp. Add a second guitarist's amp and you double the total guitar amp power you have to compete with, another 3dB increase, so you're talking 8x the power of one guitarist's rig. The drummer and vocal PA also mix in, and if they play at roughly equal volume levels to one guitarist that's another 3dB increase, so overall you're still looking at needing over ten times a single guitarist's amp to produce the volume you need to sit in the mix.
With all that said, the rule of thumb is typically:
* Sum the wattages of your guitarists' amps.
* If you can't use your band's PA to amplify your bass (too wimpy), add one-quarter that system's wattage to your running total (they'll want the same 6dB of headroom, at least, that you'll want in your rig, so really they're only using a quarter of its power if that).
* If you play with a drummer, divide what you have so far by the number of players/singers, then add that number to the sum.
* Multiply by 2.
The number you end up with is the minimum you'll want to have available to you in order to mix with all the other high-volume acoustic or amplified sources on stage. Up to double that is recommended.
So, if you have guitarists with two 50w amps, a drummer, and a 500-watt vocal/keys PA that you can't tap into, a 600w half or full stack is about the
least you'll want to show up to the gig with. Anything less and you'll likely be clipping your power amp (not good for your speakers regardless of their power handling). More is always better, because with a solid-state amp, tone isn't dependent on volume, so you can bring an overpowered amp and turn it down.
However, watts are heavy; a 2000w double-fridge rig (16x10) that you personally have to load in and out isn't going to be much fun. Bass players often do much the same as the PA guys, investing in a head that they can use with various combinations of cabinets. That way you can bring a 1200w head and a single 12" speaker to small patio gigs, then bring that same head with an 8x10 or 4x10/1x15 full stack to the House of Blues.
