how the bits fit together

what I am interested in is some very basic information on how a stereo system on the whole pieces together.

I've managed to find some very good information on very specific components. What I'm a little fuzzy about is their interaction, what equipment performs what role etc.

What I'm interested is very simple, what role each piece of equipment performs. Its input signal and its output signal.

(I won't burden people with trying to sort out the confusion in my head, I'll read this and then ask on anything further I'm not clear about.
ok ... some simple parts of a stereo and their functions....

CD transport.... this reads the information off the CD.
DA Converter.... converts the digital signal that comes off of a CD, DVD, MiniDisc etc into an anolog signal
Preamp.... this allows you to select which source you want to listen to (radio, cassette, CD, etc. etc. etc.), alter the volume and perhaps the tone of the signal.... it may also provide some gain (amplification) such that the signal that leaves the preamp may be larger than that which entered it
Power Amp.... makes the signal big enough to drive the speakers while altering it as little as possible in all other respects...
Equaliser.... changes the signal to compensate for room acoustics etc.

a normal CD Player has a CD transport and a DA converter inside it....

an integrated amp has a preamp, a power amp and often an equaliser inside it.....

a receiver contains an integrated amp and also a radio and often a DA converter.

Hope this helps.
ok followup question time...

each speaker it would seem would require a different signal. You don't want your sub trying to play the same stuff as your tweeter.

Is a spliter insterted after the amplifier? Or is it split and then each signal run through a different amplifier (1 amp per speaker, this sounds wrong)

As an alternative you could send the same signal to each speaker and have the speaker filter out the portion it will play.

To me the last method seams the best, the speaker ensures its own signal integrity this way. However the speakers I've looked inside of have no such filter, nor have I seen one discussed.

A question relating to the pre-amp/amp mix... the audio signal from a computer sound card is suitable for playing headphones etc. Is it more like the signal from an amp, or a pre-amp. And how would it behave connected to an amp or pre-amp (then amp).
There are @ least to analog outputs with a computer and they operate @ different levels.... the line out (usually on the back of the computer) from the soundcard is what is used to feed an preamp/amp.

The headphone out has had a small amount of amplification which will be enough to driver the headphones but not enough to driver big speakers.... dont plug the headphone output into the preamp/amp because the signal level is too high.

There are 2 answers to your other question....

1st let me explain a few things ...

1. the speaker box with everything in it we will call the speaker.

2. the actual speakers in the box are called drivers.


each speaker has its own signal .... now each driver in each speaker needs to get only the part of the signal that it has to play..... there are a few ways of doing this.... you can use whats called an active crossover between the preamp and the amps .... you then need an a power amp for every driver. Or you can use one amp per speaker than use a passive crossover that usually lives in the speaker which divides the signal into the right bits for each driver ....

Active crossovers with seperate amps is better but costs lots more because you need lots more electronic equipment.
lod said:
Is a spliter insterted after the amplifier? Or is it split and then each signal run through a different amplifier (1 amp per speaker, this sounds wrong)

This method is called "bi-amping" when you use two amps for each speaker to drive the tweeter and woofer seperatly. This requires 4 channels of amplification for two speakers.

If each speaker has three drivers it is called "tri-amping". Six amps (or 3 stereo amps) are needed for a pair of these speakers.

This method of powering speakers is uncommon but considered "high-end" by some. I currently use a bi-amped arrangement and I can say it makes cheap speakers sound better, and good speakers sound REALLY good =).