I'm doing something most people who know better would never do. But I do what I wanna. Jk, but seriously, I figure this is as good an opportunity to learn something as any.
So here's my sin. I have an old school mtx 81000d. It's lowest load rating is 2 ohms. Me, I run it at .5. It's pushing a 15" Zcon. It works indefinitely during winter but now that that's over it is going into a thermal protect when it is cranked. It is expected. I'm actually surprised I haven't fried it. I completely expected smoke when I first put it under a half ohm load. So now that this amp has my respect I'm curious. Is the thermal limit my only one in this case? I'm other words if I applied effort into some mods to keep it cool would this effectively expand its limits? Or is the thermal limitations further constrained by component specs? I mean I know they have there own limitations but are the thermal limitations of the amp going to be met before the individual components?
So here's my sin. I have an old school mtx 81000d. It's lowest load rating is 2 ohms. Me, I run it at .5. It's pushing a 15" Zcon. It works indefinitely during winter but now that that's over it is going into a thermal protect when it is cranked. It is expected. I'm actually surprised I haven't fried it. I completely expected smoke when I first put it under a half ohm load. So now that this amp has my respect I'm curious. Is the thermal limit my only one in this case? I'm other words if I applied effort into some mods to keep it cool would this effectively expand its limits? Or is the thermal limitations further constrained by component specs? I mean I know they have there own limitations but are the thermal limitations of the amp going to be met before the individual components?
When driving a load that is too low for an amp you are limited by the current the amp can deliver.
A 1000W amp would deliver ~22 amps into a 2 ohm load at ~44V. When you drive a 0.5ohm load it only takes ~12v to reach the same current, so you're "throwing away" 3/4 of the voltage and only getting 250 watts.
If you add one more woofer you will double the power your amp can put out. 3 more woofers will quadruple it.
That being said, you are clearly being limited by thermal issues. You can get a bigger heatsink, or lower the temperature of the air around the heatsink. The easiest way to lower the temperature of the air around the heatsink is simply bolt a bunch of 12v computer fans to the heatsink to blow away the hot air.
If the amp is in a hot trunk you could put the amp in a container (tupperware, whatever) and connect a hose with a fan to bring in cool air.
I'm not sure what you mean by wiring it higher it will get louder... The lower the impedance the more output you get.
It is indeed a dvc 1 ohm. The reason it is wired to .5 is because my amp is a mono with 2 sets of terminals. I know that generally they are wired parallel internally and it shouldn't matter which two positive a negative terminals I use but with this particular amp it doesn't seem to be the case. Only using two out of the four produces some non musical results.
It is indeed a dvc 1 ohm. The reason it is wired to .5 is because my amp is a mono with 2 sets of terminals. I know that generally they are wired parallel internally and it shouldn't matter which two positive a negative terminals I use but with this particular amp it doesn't seem to be the case. Only using two out of the four produces some non musical results.
That is only true if your amp can supply the current.
With a 2 ohm load the amp will put out 22A at 44V, which is 1000 watts (22x44 = ~1000)
With a 0.5 ohm load the amperage will rise faster as you turn the volume up and the amp will be putting out 22 amps at just 12V. As you try to raise the volume more the amp will start overheating because it cannot deliver the current and you won't get any more power. 12V x 22A is just 250 watts. (true story)
Also, your amp is only recommended for 2ohm in stereo, 4ohm in mono (look at the manual).
You should really get another woofer and wire it like this, pretend it says 1 and 2 ohms instead of 2 and 4 ohms:
http://a248.e.akamai.net/pix.crutch...enter/car/subwoofer_wiring/2DVC_2-ohm_2ch.jpg
You could also trade someone for a dual 2 ohm woofer.
Hi,
In theory yes, but not in practice. In theory you should
be getting 4KW into 0.5 ohm but in reality likely 250W.
(Depends on the inbuilt SOA/current limiting.)
No harm in using two cable runs to the driver. Wire
the driver in series and to that the cables in parallel.
rgds, sreten.
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MTX Thunder81000D 500W x 1 Mono Subwoofer Amplifier at Crutchfield.com
Hi, I see no mention of any stereo capability, rgds, sreten.
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