DUAL XPR84D 4 channel 1000 watt amplifier getting hot when idle?
DUAL XPR84D 4 channel 1000 watt amplifier getting hot when idle?
Why does it get so hot when just sitting? My room is not particularly warm or anything.
its "almost" too hot to touch. It wont burn my hand instantly but if I left it on for 30 seconds it might burn me.
it feels pretty hot and I'm worried something is not right. I'm only feeding it 12-13.8v maximum and its rated up to 14.4v normal and 16v maximum.
Its not any cooler when run at 12.0v than at 13.8v so I dont know whats up with it. could it be biased with too much current somehow?
Also I noticed the noise level is excessive when I tested a standard speaker to it when I first used it.
In full range mode the noise can be heard even with the gain on minimum. no bass boost. and full range with no high pass or low pass filters turned on.
I'm thinking maybe the internal gain is set excessively high somehow and I dont think theres any way to change it? I dont know whats causing the noise floor to be really bad or the heating up when sitting idle turned on.
it cools down when the remote wire is off and draws no current
DUAL XPR84D 4 channel 1000 watt amplifier getting hot when idle?
Why does it get so hot when just sitting? My room is not particularly warm or anything.
its "almost" too hot to touch. It wont burn my hand instantly but if I left it on for 30 seconds it might burn me.
it feels pretty hot and I'm worried something is not right. I'm only feeding it 12-13.8v maximum and its rated up to 14.4v normal and 16v maximum.
Its not any cooler when run at 12.0v than at 13.8v so I dont know whats up with it. could it be biased with too much current somehow?
Also I noticed the noise level is excessive when I tested a standard speaker to it when I first used it.
In full range mode the noise can be heard even with the gain on minimum. no bass boost. and full range with no high pass or low pass filters turned on.
I'm thinking maybe the internal gain is set excessively high somehow and I dont think theres any way to change it? I dont know whats causing the noise floor to be really bad or the heating up when sitting idle turned on.
it cools down when the remote wire is off and draws no current
You ARE aware that the power amp section isn't supplied straight from the 12-14v input, right? There's also an SMPS in-between (turning the 12-14v input to, most likely, +/- several-tens-of-volts), so there will be a few watts of loss (ie. heat) from there, in addition to the idle losses in the amplifiers themselves.
On the other hand, $98 at Walmart for <ahem> a "1000 watt" amplifier won't be much better than some (rebranded) bottom-of-the-barrel far-eastern reject anyway.
80w into 4ohms would need about +/-22v or so - that's assuming that's not the 10% THD rating.
Could we get some internal photos of the thing, perhaps?
On the other hand, $98 at Walmart for <ahem> a "1000 watt" amplifier won't be much better than some (rebranded) bottom-of-the-barrel far-eastern reject anyway.
80w into 4ohms would need about +/-22v or so - that's assuming that's not the 10% THD rating.
Could we get some internal photos of the thing, perhaps?
I seen some videos of it. it does over 240 watts RMS stereo bridged running two 4 ohm subwoofers so around 500 watts RMS total/average it is a 4 channel bridgeable amplifier
search for the model on youtube. should be top result
I have it running two 4 ohm subwoofers it gets plenty loud and the gain is not even half way turned up.
my only issue is it gets hot when just sitting idle and I dont know if thats normal.
The guy shows the internals of it in the video near the end.
I got it for 34$ at walmart a few weeks ago on sale. really good deal. brand new.
search for the model on youtube. should be top result
I have it running two 4 ohm subwoofers it gets plenty loud and the gain is not even half way turned up.
my only issue is it gets hot when just sitting idle and I dont know if thats normal.
The guy shows the internals of it in the video near the end.
I got it for 34$ at walmart a few weeks ago on sale. really good deal. brand new.
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If this is the video...
YouTube
Check out, listen, at about 4:00 minutes in when he places it on the bench. There is 'no mass'... OK the donor has taken the fixing screws off but... Tinkle. No Mass and No Thermal Mass, heatsinking. Even less concept of thermal dissipation.
First picture shows as much. I guess it is pressed steel and not much else.
Second picture 2 x 170W with what I assume to be the battery draw at 39A. 340W out 550W draw... 210W loss.
Third picture 2 x 265W with what I assume to be the battery draw at 66A. 530W out 924W draw... 390W loss.
That's down at 60% efficiency. I'm surprised it managed to run for the length of the test without pooping its thermal limit.
As to it running hot whilst idle. There is no thermal mass and there is no concept of thermal dissipation, radiation convection and such stuff.
Of course I could be wrong.
YouTube
Check out, listen, at about 4:00 minutes in when he places it on the bench. There is 'no mass'... OK the donor has taken the fixing screws off but... Tinkle. No Mass and No Thermal Mass, heatsinking. Even less concept of thermal dissipation.
First picture shows as much. I guess it is pressed steel and not much else.
Second picture 2 x 170W with what I assume to be the battery draw at 39A. 340W out 550W draw... 210W loss.
Third picture 2 x 265W with what I assume to be the battery draw at 66A. 530W out 924W draw... 390W loss.
That's down at 60% efficiency. I'm surprised it managed to run for the length of the test without pooping its thermal limit.
As to it running hot whilst idle. There is no thermal mass and there is no concept of thermal dissipation, radiation convection and such stuff.
Of course I could be wrong.
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Yes and the case is dinky. Steel is miserable as a conductor of heat and, at best, that case is made out of something like 30 gauge sheet. There is no concept of lateral heat flow in the material.
I assume or guess that when you say it gets hot at idle the heating is localised. Possibly where the PSU primary switches and output diodes are mounted. [RED]
The amplifiers, probably two 'stereo' surface mount ICs, will be mounted on the other side of the board where the bracket is. [YELLOW]. The bracket will be clamping an aluminium heatsink down on them. Look elsewhere in the forum for examples.
The PCB is mounted to the lid. In terms of heatsinking mass the ridged patterning is cosmetic but the holes in that section of the lid and the ends of the case will be there to channel air, by convection, past that aluminium heatsink.
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mine appears to be made fully out of aluminum not steel and it feels like aluminum to the touch for me. magnets dont stick to it even a little bit.
also the entire case gets hot. its not localized in any specific point. it feels hot everywhere. the sides. and top and bottom.
also the entire case gets hot. its not localized in any specific point. it feels hot everywhere. the sides. and top and bottom.
Well, on the bright side, at least the heat gets spread around then.
But (especially) if / since you got it for a paltry $34, that ought to reduce the expectations that much more 🙄
Cheap crap amp is cheap and crap - no surprises there, sorry...
But (especially) if / since you got it for a paltry $34, that ought to reduce the expectations that much more 🙄
Cheap crap amp is cheap and crap - no surprises there, sorry...
its not cheap and crap though. it works fine. just gets warm when its doing nothing.
it doesnt seem to get any warmer though when playing music.
it doesnt seem to get any warmer though when playing music.
It is a mosfet amp with a digital power supply, not a class D amp; that explains the idle heat.
A 4 channel amp with adjustable crossovers in an aluminum case for $34 is a great price.
A 4 channel amp with adjustable crossovers in an aluminum case for $34 is a great price.
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Do you use a battery to power it? If not, the voltage multiplier stage might run hot. These need a stable power source to work, if the feed is not strong enough, they heat up. Anyway, the efficency is to low for a "digital" amp, 60% is typical for a AB car amp.
DUAL is only a trade name today, they sell all kind of lowest quality electronics stuff. A long time ago it used to be honorable German brand, but it closed 20 years ago.
Return it to wall mart if you dont like it. Best you can do. Buy a good used amp at eBay instead.
DUAL is only a trade name today, they sell all kind of lowest quality electronics stuff. A long time ago it used to be honorable German brand, but it closed 20 years ago.
Return it to wall mart if you dont like it. Best you can do. Buy a good used amp at eBay instead.
I am using a battery to power it. it gets warm the same way on a battery or on a DC power supply. I tried various voltage ranges up to 15.5v
at 15.5v in 0.5v decrements down to 12v it doesnt change in idle temperature after letting it reach equilibrium for 30 minutes.
stays about the same temperature at all voltages with the power supply or with the battery.
it seems pretty hot to touch but not scalding hot. just "if i leave my hand on it for a minute I will probably get burned but touching it for a few seconds doesn't hurt me" temperature.
usually I have the battery at 13.75v constant current constant voltage with 5 amp current limit to keep the battery topped off and charged when not in use and it works great.
it has adjustable crossover in both sets of stereo channels for "front" and "rear" high pass low pass bass boost (never use bass boost. bad for subs and amps) and gain and switch for full range. high pass and low pass
I have it set so both front and rear channels are bridged to power two subwoofers.
at 15.5v in 0.5v decrements down to 12v it doesnt change in idle temperature after letting it reach equilibrium for 30 minutes.
stays about the same temperature at all voltages with the power supply or with the battery.
it seems pretty hot to touch but not scalding hot. just "if i leave my hand on it for a minute I will probably get burned but touching it for a few seconds doesn't hurt me" temperature.
usually I have the battery at 13.75v constant current constant voltage with 5 amp current limit to keep the battery topped off and charged when not in use and it works great.
it has adjustable crossover in both sets of stereo channels for "front" and "rear" high pass low pass bass boost (never use bass boost. bad for subs and amps) and gain and switch for full range. high pass and low pass
I have it set so both front and rear channels are bridged to power two subwoofers.
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Did you get this?
Changing input voltage won't change anything as it is (digitally) stepped up to a higher (constant) voltage.
The heat/high idle power usage, is normal for a class AB amp, which it is; it is not Class D.
// bass boost is not bad for amps or speakers but will cost headroom; you won't be able to play as loud.
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dayton bookshelf speakers? just ordered them.
I got these Amazon.com: Dayton Audio MK402 4" 2-Way Bookshelf Speaker Pair: Electronics
and want to know what to expect.
I got these Amazon.com: Dayton Audio MK402 4" 2-Way Bookshelf Speaker Pair: Electronics
and want to know what to expect.
From the description they look well designed and should be quite good. The sculpted corners look nice too. It’s not possible to DIY your own speaker with a real passive XO, drivers, binding posts, cabinet, and grille for $70. Let us know how they turn out. I suspect they might amaze you. Dayton makes nice stuff actually.
Looks pretty sensible, especially for that money. I suspect they'll need a bit of juice to really get going.
Chris
Chris
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