Amp/Preamp

http://www.talkbass.com/forum/showthread.php?threadid=13874&highlight=preamp

 

Hey man,
A pre amp controls the tone & stuff. A power amp gives you the power/volume.

Imagine taking apart a Bass combo amp (amp and speaker all in one) and seperating it into three parts.

In part #1 you would have all the knobs, like volume and tone. You would take all the knobs and wire them together in one box. This is your pre-amp.

In part #2 you would have the power amp. You would put the power amp into another box by it's self. You wouldn't have any knobs on this box, except for "gain" ( kind of like a volume knob ). If you had a mono power amp, you would have one gain knob, if it was stereo you would have two gain controls ( knobs ). This is your power amp.

In part #3 you would have your speaker (also called a driver). You would put the driver (speaker) into a box by it's self. This is you speaker cabinet (you probably could have guessed that).

So here's how it goes. You plug your Bass into the pre-amp. From your pre-amp you run a cord into your power amp. From your power amp you run a cord into your speaker cabinet.

The benefit to this set up is that you can change pre-amp, power amp and speakers to adjust your sound.
Say for example one Saturday afternoon you were playing at a wedding reception in someones rose garden. You could bring your pre-amp, power amp and small speaker cabinet (like a ten inch woofer with a tweeter).
Now later that night you were going to play at a big rock n' roll party. You could bring your pre-amp, power amp and a larger speaker cabinet or two (like a cabinet with four ten inch woofers, or a cabinet with two fifteen inch woofers).

Now you might ask (as I once did) "Why don't I just skip the pre-amp and plug directly into the power amp? It has a gain (volume) controls, and my Bass has tone controls." " I could save some $$$" (pre amps can be expensive).
That's a good question, but the reason it won't work is that the signal from you Bass needs to be "conditioned" before it goes into the power amp. Plus the pre-amp lets you shape your sound, which can be helpfull if the room/hall your playing in has odd acoustics.
Another cool thing is that some pre-amps also work a direct boxes, which will allow you to plug directly into the mixing board in the studio, or the mixing board when you play to thousands of screaming fans at you local club or sports arena!

And hey, it's fun to read all the information on various pre-amps, power amps, and speaker cabinets.

A word of advice. Really think about what you need before you buy. I've had two speaker cabinets (4x10 and 1x18) sitting in my living room for two years and I've only played through them once. You see, my gig was playing on Saturday night to the little kids (ages 5 to 9 years old) at church before they went to "Sunday School". Not exactly the sort of thing you need full blown concert set up for!

Plus, when you play in most clubs (and Sports Arenas for thet matter) you only need to be loud enough so that you can hear yourself on stage. It's wise to let the sound man adjust your sound for the audience. After all it's his room, and you really want to have the sound man like you. So be polite to the sound man, and you will have "The Sound of Thunder"!!!

I hope this helps.

~Andrew

 

Cordova, welcome to Talkbass. You asked a very valid question. No questions are stupid here. We are all here to gain from the experience of others. I learn new stuff everyday.

Also, Andrew Dunbar, welcome to talkbass. That was an awesome answer.

And JMX pointed out a really cool feature of Talkbass. The search is something that I use quite a bit. A lot of good stuff has been discussed in the past.

If you guys haven't already filled out your profile I urge you to do so. It takes only a few minutes and helps other know better to answer your questions.

 

Hey Andrew Dunbar!!!!


You took the words right out of my mouth!!


Very good explanation you ole techie you!*noogies*