What is Peavey doing here?

[BowerR64]

A friend of mine has a valveking cabinet hes had for years, ive never thought it sounded good but he got it cheap and its a 4X12. I do however think its built really good nice thick plywood and the cabinet looks well made.

I picked one up off craigslist today for $50. my plan was to change out the speakers and use it over at his house. It needs new cloth on the front so i opened it up to take a look at the inside. Before i unhook the speakers i took a couple of images of the wiring.

When i look at the wiring i dont really understand what they are doing here.

If you look at the back of the driver cone facing away the + terminal is on the left. On all 4 speakers

 

[BowerR64]

Here are the inputs to the speakers, i guess one is a threw or any input will drive the cabinet the same?

You can see they use blue as negative and yellow as positive. Ive read a few posts on the Peavey forum who think this is a "stereo" cabinet but i dont think it is.

Here are a few other random VK cabinets i found on google they all appear to use the same wiring as mine. At first i thought it had been rewired by the previous owner

They are using both negative leads on the 2 left side drivers, and the 2 yellow positive leads on the other side

The cab looks great on the inside IMO. This is how i wired it and it sounds night and day better which shocked me how much better it sounds now. The speakers sound more full and not thin and bright like it was before i rewired it. Both plugs to me look wired in parallel so i ran each side in series and used a + and a - to the input jack and the white lead as the series jumper on both sides the same and the same polarity. Its still the same impedance it was 16. There is a blue lead left over which is what i dont understand why they were using.

 

[royslead]

At a glance, looks like a series-parallel circuit to me.

 

[Ken]

Yes, that's one way to do series/parallel and the two jacks will take the assumed 16 ohm output to 8 ohms if you plug another 16 ohm cab in to both of them. I think...

There is an easier way to do this but it looks well done.

Ken

 

[Ghostman]

It's just a weird way of doing series parallel. The extra blue wire, as the original was wired, created the series circuit between the Left and Right speakers.

 

[BowerR64]

How is not a short?

I dont understand how you run 2 speakers off the negative side, then 2 off the positive side then hook the 2 together and it not be shorted?

The blue wire looks like its shorting both sides together.

 

[royslead]

It's not a short because the signal (voltage) has to run through the load of the speaker(s). Notice how the blue leads are on one half and the yellow are all on another half? Then the white wires are connecting the speaker positives in a parallel circuit. The single blue wire is the series connector.