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kilian
01-02-2006, 08:04 AM
And a happy twothousandandsix!

Word version:
http://members.lycos.nl/tigerarmy/So%20you%20want%20to%20buy%20an%20amp.doc

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So you want to buy an amp?
Amp is short for amplifier and this device will basically make your bass heard in a band situation, or alone in your room. We can describe three different ‘types’ of amps and we call them: head/cabinet, combo and pre/power setup. These will all be explained in this article, so are the other things like ohms, watts etc.

Please notice that I will only explain it in basic language, so you will understand the meaning of it. But you won’t get to know the theory behind.

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Head/cabinet
We’ve all seen those setups on television at the big shows, basically this is a cabinet (a box with speakers in it) and a head on top of it (the amplifier itself). Two cabinets and a head is called a stack, one cabinet and a head is called a halfstack.

The head is the device that powers up the signal of your bass and sends it to the speakers. A head exists of a pre-amp and a power-amp. When the signal of your bass comes into your head, it will first run through the pre-amp. This will colour the sound and give the characteristics of the specific amp to the sound of your bass. The equalizer is also part of the pre-amp, with this you can boost (and/or) cut certain frequencies of your signal.

After the pre-amp comes the power-amp, this will power your signal up, so it is ready to be sent to the cabinet. Solely this is what the power-amp does, some lower end power-amps will colour the signal a bit though. Not much, but still they do. When electricity is running through something, there will never be an output that is 100% the same as the input.

The cabinet, like said before, is a box with speakers in it. Most of you will know that speakers will reproduce the sound that you put into it. So that’s basically what they will do.

Combo
A combo is a head and a cabinet together, this will give you the advantage that you only need to pack one thing. The disadvantages are that you can’t cross different brands with eachother and then get a good tone. But if you like the tone of a combo, get that one.

Pre/power setup
A pre/power setup is a setup that exists of a separate pre-amp, a power-amp and a cabinet. So they’ve split the head into two devices: the pre-amp and the power-amp. Why not put them together in one? Because there are other manufacturers of power-amps that can make more powerful (and cheaper) poweramps then the standard bass amp companies. You can also switch your pre-amp easier if you don’t like your tone or have more bands and you might get more headroom in your setup. Headroom is the ‘room’ you have in your wattage section to catch the peaks your bass might deliver. When you don’t have enough headroom, it might sound weird and distorted sometimes.

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There are more things to clear up in the jungle of amps; the things I will describe next are the common terms when we’re talking about combining an amp and a cabinet.

Ohm
This is the resistance. As you can imagine, resistance plays a prominent role when we’re talking about power. If you are going to push a cube made of stone from one side of a room to the other, you won’t be happy if the floor is made of sand. It will cost a lot of power to actually move the thing. If the floor is made of ice, it will be a lot easier to push it. It is the same with the amp, when you have a higher impedance, your amp will be working with less watts (sand floor). If you have a lower impedance, your amp will be pushing out more watts (ice floor). In the manual from your amp you can read what the minimal load is from your amp, if you go lower then this: you can destroy the amp and/or cabinet.

Two 4 ohm cabinets make a 2 ohm load
Two 8 ohm cabinets make a 4 ohm load
Two 16 ohm cabinets make a 8 ohm load.
You get the game, right? Look up for the formula in your physics book. One 8 ohm cabinet and one 4 ohm cabinet makes a 2,67 ohm load and the 8 ohm cabinet won’t be getting as much wattage as the 4 ohm one does. This may lead into an unbalanced sound sometimes.

Watts
This is the amount of power that your head/power-amp delivers. This does not amount to the volume you will get. Many other factors also play a large part in that game. Ten times the wattage means that you will double the volume (in rough terms). So if you step up from an amp that is 10 watts to a 100 watt amp. You will double the volume, if the other variables are exactly the same (speaker size etc).

Speakers
10” speakers give a more pronounced sound and tend to give less bass. They will cut through pretty well, because they articulate very well. You will be able to hear what you play more easily.

15” speakers give a more boomy sound though they also tend to give more bass and sacrifice highs for that. They are slower and don’t articulate very well. You will be heard better from a distance, because of the boom they produce.

12” speakers tend to give both the advantages of 10” and 15” speakers. They are boomy and still articulate well.

These are only rough explanations and if you are going to listen to four 10” speakers, you might even notice more boom than a single 15” speaker. Use what you think sounds good. But you’re going to need some boom to play bigger venues when you need to be heard at the other side of the room. If you only use your 210 (2x10”) cabinet to let yourself be heard on stage; you’ll be fine.

Reality may prove otherwise though! So take everything with some salt.

Speaker Efficiency
1W @ 1m 99 dB
1W @ 1m 90 dB
1W @ 1m 103 dB

Guess which one will be delivering the most volume? The one with 103 dB (decibel), that’s right. This is something you want to look into when you’re going to buy a speaker. The higher the dB, the louder the speaker configuration will go with the same wattage instead of the speaker configuration with less dB. Do not stare yourself blind on this subject; if another speaker sounds way better, get that one. In the end you will listen more to the tone than to the volume.
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Tube/Solid State

The following is a direct copy of an article John (JPbass) wrote some time ago. It is a good explanation, so why not use it? I’ve added a few little things

Tube Amps; these are amps that use all tubes in the preamp and power amp sections. A preamp and power amp tube (or valve) is an electronic device that takes a signal and amplifies it. Pre amp tubes amplify the signal to a level used by the power amp tube. The power amp tube amplifies the signal so it can be fed to a speaker and heard by millions. They require an output transformer to match the impedance of the output of the tube to the speaker impedance. Depending on the wattage, these can be big and heavy. In order to work, tubes have to be heated so the electrons in the tube can move freely and amplify. I'm not going to get to technical here.

Sound: tube amps tend to have a warm sound and yield a sweet distortion when they distort.

Disadvantages: Heavy, use more electricity, tubes need to be replaced and are expensive, more susceptible to the elements (never turn on a tube amp right after it came in from the cold), more fragile (tubes don't like to be banged around).

Solid State; these are amps that use transistors to amplify the sound. They don't require the output transformer and extra heater circuitry that tube amps need. This means that they are usually lighter for the same power output. A transistor does pretty much the same thing a tube does. It takes a signal and amplifies it. It just does it in a different way. They tend to be more reliable than tube amps and can take more abuse. They also use less electricity to yield the same power output.

Sound: most solid state amps tend to have a more HiFi sterile sound; this is not always the fact though. Don’t stare blindly at this fact. They do need a more complex tone circuit. Some companies use Field Effect Transistors (FET) in the power amp stages. These tend to give a more tube amp sound since a FET amplifies in a way similar to a tube amp.

Disadvantages: No user serviceable parts. Harsher distortion (when they do distort)

Hybrid Amps; these are a combination of tubes and solid state circuitry. Usually they have a tube preamp and a solid state power amp section. This way you get the warm sound of a tube amp with the reliability of a solid state amp. In the past few years there were a lot of new amps with a tube in their pre-amp. Beware of amps that don’t even use the tube to alter the sound. Some of them might be used to buffer the signal that goes into the pre-amp, so it won’t distort the solid state section (which is unpleasant). Somebody might need to correct
me here, I’m not quite sure.

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So now you know the basic principles about amps, now it’s time to get rid of some myths that come around pretty often.

Bigger speakers have more bass then smaller speakers
The speakers itself might go down to lower frequencies, but when they are together in a cabinet, there are other rules. Don’t be fooled by this argument, I (and numerous others with me) have heard 10” speakers produce more bass (to our ears) together than a 15” speakers.

The more it costs, the better it is.
Wrong! Follow your ear and everything will be fine.

More myths to come.. Input wanted.

kilian
01-02-2006, 08:06 AM
Recommended reads and credits:

http://www.talkbass.com/ampfaq/ (way more and detailed information)
http://www.hevos.nl/engels.html (this might be in bad English, but is a good read)
http://www.recordingwebsite.com/articles/eqprimer.php (about equalizing your bass)
http://www.musicianforums.com/forums/forumdisplay.php?f=77 (The whole MX bass forum resources section)
http://www.musicianforums.com/forums/forumdisplay.php?f=58 (The whole MX bass forum lessons and articles section)

Thanks to everybody at MX who shared his or her knowledge and special thanks to Chris (Fatbandit) and Alistair (Primus_55) who checked it for spelling and grammar.

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Please remember that this is written in (I hope) language that is simple enough to be understood by everybody. If you want a detailed explanation of everything; read the talkbass amp FAQ. Although this is only a simple guide, nobody gets hurt if you know these things. So try to remember them and take a walk through the jungle of amplification.

Thanks for reading,
Kilian








The text that you have entered is too long (10154 characters). Please shorten it to 10000 characters long.
Biatches.

Now please read everything if you're going to buy an amp or want to know things. It saves a lot of time for everybody if we don't have to explain everything a thousand times, we've got this now.

Please add/correct things if necessary.
:thumb:

EDIT: I knew I had to double post.. I edited a few things and it was again bitching about the postlength.

Jublian
01-02-2006, 08:14 AM
:thumb:
good work man, i think it belongs in the resource section thought, but excellent work!!! :thumb:

Phalanx
01-02-2006, 08:37 AM
should be stickied or something

supercalifragilistic
01-02-2006, 10:21 AM
great job! very helpful :thumb:

PS: last paragraph: past tense of understand is understood ;)

Klander Brigade
01-02-2006, 10:27 AM
Nice writeup. I'll be saving this one.

sinister
01-02-2006, 10:33 AM
I came in here expecting to find a second hand amazing amp for sale really cheap.

I might not have found that, but I still wasn't dissapointed.

Great read, should definatly be put in resources/lessons after awhile.

Radiobass81
01-02-2006, 10:34 AM
My comp is currently messed up and doesn't allow me to do it, but you'll be getting repped by me :p.

:thumb:

Radiobass81
01-02-2006, 10:36 AM
You forgot digital amps!

Sure, right now there's only a few of us (Roland, Yamaha, that other expensive brand), but you'll see!

bottlerocket
01-02-2006, 10:51 AM
I'll sticky this for a few days so everyone can read it, and then I'll move it to the resources forum. I just think it'll get a lot more traffic that way.

Great job, man...very nice. Rep ++ for you.

:thumb:

-Gav

Jimbobntnr
01-02-2006, 11:08 AM
great job kilian!

fatbandit
01-02-2006, 11:12 AM
Yeh, great stuff kili!

The spelling is all good (you got primus_55 to spellcheck it, right?) but a couple of words are wrong, or gramatically incorrect. It wouldn't take too much effort to fix them, but you've done a great job already man!

:smash:

Riouken
01-02-2006, 11:21 AM
I'll sticky this for a few days so everyone can read it, and then I'll move it to the resources forum. I just think it'll get a lot more traffic that way.

Great job, man...very nice. Rep ++ for you.

:thumb:

-Gav
Hey gav, shouldn't we put this in Resources or Lessons?

It just seems more relevant there.

kilian
01-02-2006, 11:26 AM
Yeh, great stuff kili!

The spelling is all good (you got primus_55 to spellcheck it, right?) but a couple of words are wrong, or gramatically incorrect. It wouldn't take too much effort to fix them, but you've done a great job already man!

Be so kind to help me out here then :thumb: Thanks for the great comments and rep (altough I don't even know where to look to see if I got any).

Riouken; the reason I posted it at the mainpage is that more people will actually look at it then. You're right that it should be moved to the resource section (eventually).

About the digital amps; I don't know much about them or know any disadvantages/advantages.

Riouken
01-02-2006, 11:29 AM
That's cool man. I wasn't trying to rain on your parade or anything.

bottlerocket
01-02-2006, 11:40 AM
Hey gav, shouldn't we put this in Resources or Lessons?

It just seems more relevant there.

Re-read my post...I'll move it there eventually, I just want it to get some traffic first. :p

:thumb:

-Gav

Riouken
01-02-2006, 12:03 PM
Oh ok sorry about that.

sixner
01-02-2006, 12:06 PM
wow, thats great.
Were you just bored? or was this a favor to someone or....? just curious

-Sixner

SixnStones
01-02-2006, 12:31 PM
10/10 for style

kilian
01-02-2006, 12:49 PM
That's cool man. I wasn't trying to rain on your parade or anything.
I know :thumb: Should have put a smiley next to it! Bloody internet ;)

wow, thats great.
Were you just bored? or was this a favor to someone or....? just curious

-Sixner
Because there were a lot of questions asking about amps and I thought this would help a little. And the fact that I couldn't open a thread and it said: wait for edge! He will explain all!

That bothered me, because if you pay a little attention to what he says, you can actually remember those things and answer a lot of the same questions later on. Instead of saying: wait for edge! ;)

bottlerocket
01-02-2006, 01:06 PM
Oh ok sorry about that.

Hey, don't sweat it. You're always bustin' my balls for something. ;)

:thumb:

-Gav

Riouken
01-02-2006, 01:24 PM
:lol: No I'm not!!!

P.S. It's not good for a mod to use that language though is it? Must I send an e-mail? :o






Joking of course.


DAMN! you! Yes you! That's you mr person looking at the screen! You took me seriously! "balls is a swear word?" Damn, I bet you feel foolish!

bottlerocket
01-02-2006, 05:45 PM
Moved to Resources section.

:thumb:

-Gav