Clockworkmike
Well-Known Member
Recently I was replacing the speaker cables to my amplifiers and figured Id share a quite unfortunate and cautionary tale about the dangers of plugging into the wrong inputs and wrong impedances.
In 2003, i had been playing for about 7 years but i was still young and unfamiliar with a lot of the workings of amplifiers. But i bought a brand new a Marshall Mode Four with two MF400B cabs because from local store. I told them I wanted a full stack version and they were all too happy to oblige but told me they couldnt get a slant cabinet or the MF280 series cabinets, but id like the straight MF400B cabs better anyways. What they didnt inform me of ( or rather what i wasnt self informed of as well) was the MF400 A/B cabs were 8ohm, single input cabinets and were designed to only be used in a half stack configuration with the Mode Four 350w head. In order to get the matching full stack, you would have needed two of the MF280 A or B cabinets, that were 16ohm rated each, which is what the head required to operate on.
I paid a pretty decent sum of money for the amp and took them at their word I was making a good choice. Took the amp home, set it up and began cranking up the volume, only to hear POP! about 15mins in. I freaked out, called the shop and they laughed, telling me to bring the head back and grab another.
Amazingly this one worked for about 4 months in that configuration but one day, I cranked it up again and POP! This time, i had to contact Marshall and paid to ship it to an authorized repair tech. The tech called me and asked "what in the hell have you done to this thing?! "But I told him " Nothing, I just used the amp, cabs and guitar and it blew up again!" So he repaired it and sent it back under warranty, not knowing I had the wrong cabinet and neither did I myself.
Whatever he did, managed to keep the amp together as it was a while afterwards before I began to learn about the importance of impedance and mixmatching different ohm cabinets.
These days its set up as a halfstack and works properly with no issues, while the other cabinet is being used on another amp. But it shows how unscrupulous/ignorant local dealers can sometimes be and how easily you can destroy your own gear that you bought with your hard earned money.
Take note of your gear and educate yourself on speaker loads folks, it might save ya!
In 2003, i had been playing for about 7 years but i was still young and unfamiliar with a lot of the workings of amplifiers. But i bought a brand new a Marshall Mode Four with two MF400B cabs because from local store. I told them I wanted a full stack version and they were all too happy to oblige but told me they couldnt get a slant cabinet or the MF280 series cabinets, but id like the straight MF400B cabs better anyways. What they didnt inform me of ( or rather what i wasnt self informed of as well) was the MF400 A/B cabs were 8ohm, single input cabinets and were designed to only be used in a half stack configuration with the Mode Four 350w head. In order to get the matching full stack, you would have needed two of the MF280 A or B cabinets, that were 16ohm rated each, which is what the head required to operate on.
I paid a pretty decent sum of money for the amp and took them at their word I was making a good choice. Took the amp home, set it up and began cranking up the volume, only to hear POP! about 15mins in. I freaked out, called the shop and they laughed, telling me to bring the head back and grab another.
Amazingly this one worked for about 4 months in that configuration but one day, I cranked it up again and POP! This time, i had to contact Marshall and paid to ship it to an authorized repair tech. The tech called me and asked "what in the hell have you done to this thing?! "But I told him " Nothing, I just used the amp, cabs and guitar and it blew up again!" So he repaired it and sent it back under warranty, not knowing I had the wrong cabinet and neither did I myself.
Whatever he did, managed to keep the amp together as it was a while afterwards before I began to learn about the importance of impedance and mixmatching different ohm cabinets.
These days its set up as a halfstack and works properly with no issues, while the other cabinet is being used on another amp. But it shows how unscrupulous/ignorant local dealers can sometimes be and how easily you can destroy your own gear that you bought with your hard earned money.
Take note of your gear and educate yourself on speaker loads folks, it might save ya!
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