Speaker Wiring

[Walt-Dogg]

It just came to mind that there's the possibility that the speakers might not be wired right in my 412L. Could anyone tell me how they should be wired (series or parallel, or some crazy design Conrad came up with) and a diagram? So I could check myself and see?

[HRobert]

There could be several ways that the cabinet could be wired.  If you have 4 - 16 ohm speakers, the wiring could be either all  in parallel to give you a 4 ohm load, or series / parallel for a 16 ohm load.  

If you have all 8 ohm speakers, the wiring is usually in a series / parallel configuration to give an 8 ohm load.

[Walt-Dogg]

It has the original 4 - 8 ohm speakers for an 8 ohm load (8 ohm load to my knowledge that is). You know it's probably in the catalog... *checks catalog* ...Doesn't say... Hmm, I guess I should just pull it open and see how it is wired as opposed to how it should be wired. So how should a stock 412L be wired?

[EdBass]

Mr. Sundholm had been "done with Sunn" for the better part of a decade before your 412L was designed, so it's pretty unlikely that it's "some crazy design Conrad came up with". 
The only 4x12 during his era was the 42" high X 24" wide Sceptre cab AFAIK.

If you have all 8 ohm speakers, the wiring is usually in a series / parallel configuration to give an 8 ohm load.

Series/Parallel is indeed probably the most common four driver cabinet wiring, and the 1979 catalog shows the cabinet as being 8 ohms, so if it has 8 ohm drivers in it, series/parallel it is.
If they are indeed 8 ohm drivers, and intend to keep the power distribution even across all drivers, you have the choice of 32, 8, or 2 ohms.

What is the impedance of the drivers, and what impedance do you want the cab to be?

[Walt-Dogg]

My mistake, I'm not too versed in the history of Sunn.

It's the original 8 ohm speakers and the cab is supposed to be 8 ohms, which I want it to be.

[stanner]

i have that cab and i witnessed GregAnderson  in GoatSnake using one lastnite and it killed!
four 8 ohm spkrs in two's wired in par= 4ohm plus two spkrs wired in par-add them in series 4&4  to get 8 0hms.
(i think thats how its done-i could be wrong and i'll eat a bug)

[Walt-Dogg]

So what kind of diagram am I looking for then? If I want an 8 ohm load from 4 - 8 ohm speakers/

[foxfire]

have a look here, http://www.colomar.com/Shavano/spkr_wiring.html or if you have a multimeter you can save yourself the hassle of removing any speakers...

[Walt-Dogg]

Well I cross checked my speakers' wiring to a series/parallel diagram I found. They matched. So I guess the cab just doesn't sound that good.

[EdBass]

There are only three eras of Sunn history;

Sundholm - Inception to '71?
Hartzell -  '71 until '86 or '87?
Fender - late 80's until the end. Fender still owns the name.

IMO the quality, tone, and collectabilty dropped from era to era.

Here's a chart;

[Walt-Dogg]

That one's a bit more confusing than the one I used, but yeah my cab's wired correctly for an 8 ohm load.

And EdBass I'll keep that in mind. Thanks.

[mckinnon audio]

  The big difference here is if you wire the cab series/parallel,and one driver fails,you also lose the one it's in series with,so now you're running on two drivers.If you wire it parallel/series,and one driver fails,the other three keep working,except one will be lower in volume because it's parallel "mate" is now open and the impedance will double on that leg,good luck,Mel.

[JonO)))]

have a look here, http://www.colomar.com/Shavano/spkr_wiring.html or if you have a multimeter you can save yourself the hassle of removing any speakers...

I recently acquired myself a Beta Bass, but with only one 410 (each speaker rated at 8 Ohms, presumably wired in series/parallel to give an overall impedance of 8 Ohms), I was wondering how I could rewire the 410 to 4 Ohms to get the full use of the amp (100W at 4 Ohms).

The document that Ed provided the link to doesn't show this to be possible (at least, not with only 4 speakers), though in theory it must be - presumably if there are two sets of 2 speakers wired in parallel, and those two sets then wired to the other in series?

Jon.

[Isaac]

"in theory it must be"? Why? In fact, it is theory that says it is not.