vintageHIWATTconvention.com

Hello, I've been having some problems with my late 70's front loaded/ported cab w/ fane 125155 speakers.

This past week I checked the impedance and it comes all the way up to about 24 ohms. I checked the individual speakers though w/ wiring harness still attached and three came out to 12 ohms, however one came out to around 36 ohms? I checked impedance externally w/ plug and from the input jack(internally) still seems to come out consistently at 24 ohms.

I also checked for speaker rub and any buzzing or distortion coming from speakers I don't really notice any.

When I play thru the cab w/ my heads at 16 ohms maybe it is a bit quieter than my mesa 4x12 at 8 ohms. But the individual speakers still seem tight enough and no buzzing bottom or cone damage far as I can tell.

I remember seeing a wiring layout( I'm sure it's series parallel but seemed a tad different from a marshall) for these cabs?

Anybody have any ideas as to what might have happened? I usually test this cab and it's always come out to 12 ohms from the input jack.

I'd hate to have to see her go...

DOH!

Just responded to your post on PP:

The only way to get a reliable reading off one speaker is to have it disconnected. Resistance/Impedance will always take the path of, well, least resistance...

A DCR reading of 24 ohms would make me suspect you're only catching one series side of the cab (32 ohms impedance). If nothing has been altered, it sounds like a lead has broken somewhere. Check the wiring at the jack itself. Do you have two leads going to each terminal there or is the cross connect made at the speaker terminals? Are you using braided wire?

Original HIWATT wiring was more artist than Marshall's. Here's what it looked like out of the factory: http://hiwatt.org/Layouts/CabWiring.jpg

You can wire them like a Marshall, though, with the same end result.

Dave

I'll bet the one reading high is open circuited, and one open in the normal 4x16 hookup would cause the higher reading you're seeing.

--mark