Suggestions for use with extra speakers?! Surround Sound, maybe?

Question

I have 6 speakers from old stereos that have broken, and i have one stereo left. The stereo has only a left and right speaker and the speaker's impedance are 6 ohms. All the other speakers are 8 ohms. Do the ohms matter, or can i mix and match the speakers... and what can i do with all these extra speakers, i would like to set up surround sound or somthing using this stereo, but idk if its possible. Is it? Any other suggestions. Thank you for your time!

Answer 1

Ohms matter. Impedance, expressed in Ohms, is the "resistance" (or load) the amplifier "sees". If you were to try and connect more than one speaker per output there are a few things you should be aware of...

If you were to "daisy chain" them, or more precisely, connect them in parallel, the amplifier would "see" 2 (two) 8 Ohm speakers as 1 (one) 4 Ohm speaker. Parallel halves the impedance, which may seem like a good thing, and it can be, at times. First of all the amplifier can output more wattage, but bare in mind that it is also more taxing on the amplifier to supply power to lower impedances (i.e. 4, 2, 1 Ohms).

Many consumer geared amplifiers (and receivers) can handle 4 Ohm loads, though they are designed for 8 Ohms, which is way most consumer based loudspeakers are 8 Ohm.

There is another way to wire multiple speakers to the same output which is called "series". When wired in series 2 (two) 8 Ohm speakers become 1 (one) 16 Ohm  speaker. It is the opposite of parallel in that it doubles the impedance.

To wire in parallel:

You can do so in by wiring the first speaker as you normally would, and take another speaker cable and connect the second speaker to the first speakers inputs, positive "+" to positive "+" and negative "-" to negative "-". Or you can run two speaker cables to each speaker from the amplifiers output.

To wire in series:

First you connect one speaker wire between the positive "+" output of the amplifier to the positive "+" input of the first speaker. Second, take another speaker wire and connect it to the negative "-" input of the first speaker and connect it to the positive "+" input of the second speaker. Third, you take another speaker wire and connect it to the negative "-" input of the second speaker and run it back to the negative "-" output of the amplifier.

Of course all above examples were for 1 (one) channel of the amplifier, right channel for example.

Also there is what is called "Matrix" it is a way to wire in a rear surround channel into (or out of) a stereo amplifier...

I haven't done this in years, and hopefully I remember it correctly (I believe I have)...

It is very much like wiring in series, except that you connect the second speakers negative "-" input with the left channels negative "-" output, assuming you started wiring the speakers at the right channels positive "+" output. It in effect nulls the "center" signal (what both channels would produce in a stereo setup) and you hear just the "left" and "right" audio signal, albeit in mono. It's basically what Dolby Pro Logic did before the advent of 5.1 digital surround encoding.

If you try any of these wiring setups, be aware of the potential consequences...

over driving you amplifier and ruining it. So read the linked .pdf article below for better insight into the series/parallel business (it's for car audio applications but applicable).

Any questions e.mail be or add to your question...

Good Luck