second hand marshall cabainet wired wrong

ryan.kroemer@bigpond.com · 03-06-2008, 12:44 AM

hi have just aquired a second hand marshall box cheaply the guy that owned it changed wiring cofigeration (ohms) and box didn't work so sold to local music shop and was re-wired to correct 8 ohms as stated on back of box.

my problem is the guy that re-wired it back to original ohms is a srcew loose after all the drugs he has done in the 60' and 70' and i want to know is there is some way you can tell the cabainets total ohms just to be on the safe side.

i don't own a voltimeter so a method without using one of these would be good but i can get a hold of one and are friends with a sparky, would like to learn how to do this on my own though.
any help would be good. the box is a mg412" marshall 120watts my head is a 50watt valve head with 4,8,8,16,16ohms speaker outs on back.

ZoomZilla · 03-06-2008, 10:57 AM

Tell me what speakers are in it and describe the wiring. It's not hard to figure it out.

ryan.kroemer@bigpond.com · 03-07-2008, 06:50 AM

Quote:

Originally Posted by ZoomZilla

Tell me what speakers are in it and describe the wiring. It's not hard to figure it out.

i wil tell you next week when i pick it up. put a hundred on it and they put it aside for me.
i think they are the original speakers that come in the mg4-12" marshall cab. gose with mg solid state marshalls range head. from what i know they are celestion disinged for marshall for that cab to get a punchy sound. the total box watts is 120rms.
cheers thanks for your help

ZoomZilla · 03-07-2008, 12:21 PM

When you get it, open the back and snap a pic, it will take about 2 seconds to tell you what you are dealing with.

ryan.kroemer@bigpond.com · 03-12-2008, 12:26 AM

hi
here is the pictures you wanted of the inside of my marshall box. the two wires hangin' freely were atatch to input jack unplugged then to get right in there for close up photo. i think it is wired to 8ohms but want a second opinion as i'm no expert. the best results i could get with my phone don't own a digital camera.
cheers ryan.

ZoomZilla · 03-12-2008, 12:27 PM

Ok, that is wired in series/parellel so what that basically means is whatever ohms the speakers are, that's what you cabinet ohms are. so if you have 8 ohms speakers in there. I can't tell by the pic, but it would make sense they are 8 ohms. So if they told you that it is wired in 8 ohm, I would believe that to be true. I will give you a tip. since those have quick connects, you might take a soldering iron and solder the connects to the terminal. That's what I did. I rewired mine to parallel and used quick connects in case I wanted to change it up, then I soldered the quick connects to the speaker terminals. You don't have to be good at soldering either. Use a 30 or 40 watt iron and some rosin core solder, just get the iron hot and hold it on the quick connect, then put the solder in the groove of the quick connect where it meets the terminal, when it is hot the solder will flow to that area, then just remove the heat source. Obviously the groove part of the quick connect needs to be facing you. Not needed, but quick connects are not the most stable connection, so I always like to solder mine in place.

ryan.kroemer@bigpond.com · 03-12-2008, 07:14 PM

hi
thanks for your reply and help. the speakers are original spealers in box and plate on back of box says 8 ohms so i would say they are 8 ohms speakers. will look when i solder connectors. yeh that is a good idea as i found out the hard way years ago when a connector vibrated loose on my old ashton box thank god it was only at practice and not a show.

cheers ryan

P.S.
love the tight punch the marshall box has

03-06-2008, 12:44 AM	#1 (permalink)
ryan.kroemer@bigpond.com Junior Member Join Date: Mar 2008 Posts: 15	second hand marshall cabainet wired wrong hi have just aquired a second hand marshall box cheaply the guy that owned it changed wiring cofigeration (ohms) and box didn't work so sold to local music shop and was re-wired to correct 8 ohms as stated on back of box. my problem is the guy that re-wired it back to original ohms is a srcew loose after all the drugs he has done in the 60' and 70' and i want to know is there is some way you can tell the cabainets total ohms just to be on the safe side. i don't own a voltimeter so a method without using one of these would be good but i can get a hold of one and are friends with a sparky, would like to learn how to do this on my own though. any help would be good. the box is a mg412" marshall 120watts my head is a 50watt valve head with 4,8,8,16,16ohms speaker outs on back.

03-06-2008, 10:57 AM	#2 (permalink)
ZoomZilla Senior Member Join Date: Dec 2007 Posts: 145	Re: second hand marshall cabainet wired wrong Tell me what speakers are in it and describe the wiring. It's not hard to figure it out.

03-07-2008, 12:21 PM	#4 (permalink)
ZoomZilla Senior Member Join Date: Dec 2007 Posts: 145	Re: second hand marshall cabainet wired wrong When you get it, open the back and snap a pic, it will take about 2 seconds to tell you what you are dealing with.

03-12-2008, 12:27 PM	#6 (permalink)
ZoomZilla Senior Member Join Date: Dec 2007 Posts: 145	Re: second hand marshall cabainet wired wrong Ok, that is wired in series/parellel so what that basically means is whatever ohms the speakers are, that's what you cabinet ohms are. so if you have 8 ohms speakers in there. I can't tell by the pic, but it would make sense they are 8 ohms. So if they told you that it is wired in 8 ohm, I would believe that to be true. I will give you a tip. since those have quick connects, you might take a soldering iron and solder the connects to the terminal. That's what I did. I rewired mine to parallel and used quick connects in case I wanted to change it up, then I soldered the quick connects to the speaker terminals. You don't have to be good at soldering either. Use a 30 or 40 watt iron and some rosin core solder, just get the iron hot and hold it on the quick connect, then put the solder in the groove of the quick connect where it meets the terminal, when it is hot the solder will flow to that area, then just remove the heat source. Obviously the groove part of the quick connect needs to be facing you. Not needed, but quick connects are not the most stable connection, so I always like to solder mine in place.

03-12-2008, 07:14 PM	#7 (permalink)
ryan.kroemer@bigpond.com Junior Member Join Date: Mar 2008 Posts: 15	Re: second hand marshall cabainet wired wrong hi thanks for your reply and help. the speakers are original spealers in box and plate on back of box says 8 ohms so i would say they are 8 ohms speakers. will look when i solder connectors. yeh that is a good idea as i found out the hard way years ago when a connector vibrated loose on my old ashton box thank god it was only at practice and not a show. cheers ryan P.S. love the tight punch the marshall box has

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode