Two 1960a cabs labelled 16 ohm were actually 8

[wallythacker]

I thought I'd throw this out there just because.

Over the last couple months I've been buying Marshall stuff when I see it cheap. Two 1960b cabinets were in that lot.

Both cabinets are older, being JCM 800 lead series. Both have the single jack on the back. Both are labelled 16 ohm. Both in reality are 8 ohm.

Imagine my surprise when I opened the first one to see all the 12GT75's had 8 ohm marked on them. Thinking someone had goofed with the labels I used a multi-meter and got a 7.7 ohm reading. Close enough. I wasn't as surprised when I opened the second cab to find, again, they were all marked 8 ohm. Multi-meter, again, got a 7.7 ohm reading. Cab was marked 16 ohm.

I can't count over the years, especially my early years, how many rental cabs and friends cabs I plugged into. How many of these cabs were 8 ohms? I don't know. But I know my head was expecting 16 ohms.

edited: got confused. 'A' cabs mis marked, not B.

 

[GIBSON67]

Re: Two 1960b cabs labelled 16 ohm were actually 8

Good point! I always meter any new cabs before I use them. Actually with my OCD, I open them up...check the wiring, check the jack to make sure everything is snug, check the phase of all the speakers...and then I meter the cab before I button it back up.

 

[Ken]

Re: Two 1960b cabs labelled 16 ohm were actually 8

Most 8 ohm cabs were for the Canadian market. They're out there but not common.

It's curious that they were labeled 16 ohms because I've never seen a Marshall cab with the impedance mislabeled. Wattage yes, but not impedance. I would suspect those speakers or the cabinet backs are not original. Pics?

Ken

 

[wallythacker]

Re: Two 1960b cabs labelled 16 ohm were actually 8

Ken,

Bear with me. I'm not as savvy on posting pics as I should be. It may be a couple of days. What's interesting, in my mind, is these cabs came from opposite ends of our population. Both don't appear to me to have seen many road miles. Maybe away back when they came over on the same boat. Who knows.

You know, if there were a lot of these wrongly marked cabs it explains why my beloved 800 died an ugly death in the late 80's. (It didn't die but did need a new transformer and other work.)

I'm really curious now and tempted to visit all the 1960a cabs I see advertised for sale with ohmmeter in hand.

 

[pleximaster]

Re: Two 1960b cabs labelled 16 ohm were actually 8

JCM 800 were often 8 ohm in the scandinavian countries and i have had a few labeled 8 ohm on a sticker over the badge saint 16 ohms. could be that labels have fallen off...

best plexi

 

[wallythacker]

Re: Two 1960b cabs labelled 16 ohm were actually 8

JCM 800 were often 8 ohm in the scandinavian countries and i have had a few labeled 8 ohm on a sticker over the badge saint 16 ohms. could be that labels have fallen off...

best plexi

This ^^ makes sense . But in my day I NEVER saw a label OVER a cab label that corrected the impedance, and I saw a lot of cabs. It appears there was a LOT of misbadged cabinets in Canada. I got an answer from a guy selling a jcm 800 cab and guess what? Another 8 ohm labelled as a 16.

1 is an anomaly. 2 is co-incidence. 3 is a pattern.

Marshall managed to keep this gaffe hidden well over the years. Google shows nothing.

I smell vintage heads melting down all over the place.

ETA: There is an up side for me. I have been buying nice speakers cheap, Swamp Thang, Texas Heat, Govnor's because they were 8 ohm units and the ex-owners didn't think they would work in any 1960 cab as they were all 16 ohm. I didn't intend this, I had the speakers bought before I knew this. Now? I can experiment to high heaven without ruining anything.

 

[Micky]

Re: Two 1960b cabs labelled 16 ohm were actually 8

ETA: There is an up side for me. I have been buying nice speakers cheap, Swamp Thang, Texas Heat, Govnor's because they were 8 ohm units and the ex-owners didn't think they would work in any 1960 cab as they were all 16 ohm. I didn't intend this, I had the speakers bought before I knew this. Now? I can experiment to high heaven without ruining anything.

You are gonna love Eminence speakers in that cab...

 

[SG~GUY]

Re: Two 1960b cabs labelled 16 ohm were actually 8

where are ya taking your ohm readings?

at the jack?

I thought I'd throw this out there just because.

Over the last couple months I've been buying Marshall stuff when I see it cheap. Two 1960b cabinets were in that lot.

Both cabinets are older, being JCM 800 lead series. Both have the single jack on the back. Both are labelled 16 ohm. Both in reality are 8 ohm.

Imagine my surprise when I opened the first one to see all the 12GT75's had 8 ohm marked on them. Thinking someone had goofed with the labels I used a multi-meter and got a 7.7 ohm reading. Close enough. I wasn't as surprised when I opened the second cab to find, again, they were all marked 8 ohm. Multi-meter, again, got a 7.7 ohm reading. Cab was marked 16 ohm.

I can't count over the years, especially my early years, how many rental cabs and friends cabs I plugged into. How many of these cabs were 8 ohms? I don't know. But I know my head was expecting 16 ohms.

 

[MartyStrat54]

Re: Two 1960b cabs labelled 16 ohm were actually 8

Don't mix any of those Eminence's with the G12T-75's as they will drown them out. The 75 has a 97db rating and all the Eminence speakers you listed are 100db+.

 

[Clammy]

Re: Two 1960b cabs labelled 16 ohm were actually 8

JCM 800 were often 8 ohm in the scandinavian countries and i have had a few labeled 8 ohm on a sticker over the badge saint 16 ohms. could be that labels have fallen off...

best plexi

I have a number of Canadian market cabs with little "8Ω" stickers over the 16Ω marked on the tags. I can see how those little things could fall off, or get torn off over time.

I've never seen a label with the incorrect impedance indicated on it.

Cheers!

 

[wallythacker]

I tried multi-quoting. Another day maybe.

I'm taking the reading at the jack but I've got some pics now to upload once I figure how. (they are on my phone) that show the 8 ohm marking on the speakers and the cab.

I know the 12gt75 will get drowned out. For now I'm dropping 3 swamp thangs in and leaving a 12g75 just to keep the impedance proper. I won't hear it but I'm not concerned.