majestic amps

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Mid-late 80's Majestic products ranged from flea market ** to just plain cheaply made. I worked at a shop in '86 that sold them, and would have recommended a high-power head unit over their amps.

But by 1990 they were advertising in the magazines with spec's that weren't quite as over inflated, and better looking hardware. As an example, their 400Wx2 amp actually made 200Wx2 at rated THD. That didn't lend much good will toward the product in my eyes, but they appeared to be making progress.



There's a good chance that, like Pyramid, they found someone to design or build higher quality products for them by '93 or so. Maybe someone will definitively know. I wouldn't buy one myself because there are many other brands out there with a fine legacy to be picked up in the $50 range.
 
I've got an old Majestic MA-9400 (2x200W/1x400W claimed) that I fixed many years ago.The power rating seems to be inflated a bit,but it really isn't a bad amp,perfectly suitable for bass duty which is what I've always used it for. IIRC the output transistors are 2SB688 and 2SD718,and are rated for 80W each.There are two pairs per channel.
I have abused it a bit,and it keeps soldiering on.Once I even shorted the speaker leads on one channel(I was unaware they had come out of the speaker terminals and were shorted) and cranked it up while trying to figure out what was wrong,and it didn't even explode.When I discovered the shorted speaker leads on that channel,they were warm(!),so it was cranking some power into the shorted leads. I thought for sure that channel was going to be dead,but it's still working fine.
I have a crummy schematic posted HERE
I have done a couple small mods to the Majestic,increasing the filtering/storage capacitance,and installing another pair of FET's in the PSU.The board had room for 4 pairs of FET's,but only 3 pairs were installed. The original FET's were 6x BUZ71A (that "A" is important!) and I eventually ended up swapping them for 8x IRFZ44.

I later discovered that a "Rockwood" amp that my friend had was basically identical,the main differences being that his was a 4 channel amp,and only had one pair of outputs per channel. That (also crummy) schematic is HERE

A few years ago another friend had a newer Majestic 4-channel amp that he had problems with(meltdown),and returned/exchanged a few times before he finally got a different amp.
This older '9400 seems pretty tough though,it's been going strong for the last 10-15 years or so.
 
Yeah it is strange I have always had ppl say dont buy them, but my dad bought new for his 94 sentra a Majestic M7400 (forget the lettering, but the number is right) was a 50x4 @4 rms amp. It ran in the nissan 3 channel for 8 years fronts at 2ohm and bridged 4ohm for a sub. then 5 years as a 4 channel in my rodeo for doors. now it is back in his truck running doors. It has only shutdown once from thermal protection when we still lived in arizona it was quite hot and ozzy was nice and loud. Let it sit for a bit, turned it back on, and instant joy factory again. it has run non stop for 15 years only out of a car for a few weeks at most. Now granted it was only one amp so it shouldnt speak for them all so milage will very is what i have learned.
Zippy
 
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