Hi All,
I got this vintage beast today, and when doing a bit of reading about it, came across this info: "Designed to run comfortably at 375 watts at 2 ohms".
Holy shit.
Am I going to blow everything up with this thing? Anyone have any experience or tips pairing it with a cab?
Acoustic 270 Amp - 2 ohms?
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- Blood_mountain
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Re: Acoustic 270 Amp - 2 ohms?
Might need to rewire a cab, but those things sound really good. I can’t remember if it was Harriet the Spy (an old Jamie stilan band) or another band touring with them, but they were using that head and it slayed.
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Re: Acoustic 270 Amp - 2 ohms?
Two 4-ohm cabs is the equivalent of 2 ohms! And running the amp through cabs with higher impedances won't hurt anything. It'll be less efficient at 4 ohms, but still probably plenty loud enough. You won't blow anything up! I have one, and it sounds great through a typical 4-ohm 4x12. That said, Acoustic cabs can be found really cheaply all over the place, if you just want to track down a matching 2-ohm cab.
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Re: Acoustic 270 Amp - 2 ohms?
That's just marketing talk meant to say that it's designed with two ohms in mind, you don't need a 2Ω cabinet to make it work.
Furthermore, while I understand Acoustic amplifiers are highly regarded, at least in some circles, I would not take that to mean that the amp prefers working into 2Ω loads, especially for low frequencies. Just run the cab you've got without rewiring it. I'm a fan of sticking with 8Ω when running solid state, so those times you decide to live it up and hang two cabs off your amp you're still only loading the amp up to 4 which will sidestep thermal cut-out or actual failure in the output sections (and be warned, a lot of Acoustic amplifiers are NOT well documented on the schematic side of things and are therefore more challenging to your neighborhood shade-tree tech).
Furthermore, while I understand Acoustic amplifiers are highly regarded, at least in some circles, I would not take that to mean that the amp prefers working into 2Ω loads, especially for low frequencies. Just run the cab you've got without rewiring it. I'm a fan of sticking with 8Ω when running solid state, so those times you decide to live it up and hang two cabs off your amp you're still only loading the amp up to 4 which will sidestep thermal cut-out or actual failure in the output sections (and be warned, a lot of Acoustic amplifiers are NOT well documented on the schematic side of things and are therefore more challenging to your neighborhood shade-tree tech).
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Re: Acoustic 270 Amp - 2 ohms?
Thanks for the responses everyone! I took it to a local music shop and ran it through a 4 ohm cab. I bought this thing as-is for super cheap, knowing only that it powered on, so I was happy that it seems like everything is in working order minus some scratchy pots.
So that said, I'm planning to give it a good internal cleaning, but having a quick look at it last night it wasn't immediately evident how to get it apart. Tips?
So that said, I'm planning to give it a good internal cleaning, but having a quick look at it last night it wasn't immediately evident how to get it apart. Tips?
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Re: Acoustic 270 Amp - 2 ohms?
We had a 270 at our rehearsal space for a year, on loan from an engineer dude (it was previously on the road with a big country band). Seem to remember it was paired with this cab: https://www.ebay.com/itm/Acoustic-Contr ... 3097430525
It sounded awesome, sadly a visiting "musician" inexplicably ruined it by maniacally twiddling the pots, so definitely don't do that. It is now back with the owner, who I'm guessing fixed it himself. I'm thinking of buying one these days, if not that one I've found other specimens for reasonable prices.
I never opened it though, and could only find one picture of the guts. From what I can see, the screws holding the inside to the outside are on the sides, so probably remove those and carefully slide the amp chassis out forwards or backwards.
It sounded awesome, sadly a visiting "musician" inexplicably ruined it by maniacally twiddling the pots, so definitely don't do that. It is now back with the owner, who I'm guessing fixed it himself. I'm thinking of buying one these days, if not that one I've found other specimens for reasonable prices.
I never opened it though, and could only find one picture of the guts. From what I can see, the screws holding the inside to the outside are on the sides, so probably remove those and carefully slide the amp chassis out forwards or backwards.
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Re: Acoustic 270 Amp - 2 ohms?
Great, thanks for the advice!frodog wrote:We had a 270 at our rehearsal space for a year, on loan from an engineer dude (it was previously on the road with a big country band). Seem to remember it was paired with this cab: https://www.ebay.com/itm/Acoustic-Contr ... 3097430525
It sounded awesome, sadly a visiting "musician" inexplicably ruined it by maniacally twiddling the pots, so definitely don't do that. It is now back with the owner, who I'm guessing fixed it himself. I'm thinking of buying one these days, if not that one I've found other specimens for reasonable prices.
I never opened it though, and could only find one picture of the guts. From what I can see, the screws holding the inside to the outside are on the sides, so probably remove those and carefully slide the amp chassis out forwards or backwards.
When you've seen them for sale, what are they typically selling for? I'll likely flip this one at some point.