Amp Protection Mode?
Thread Starter
Joined: Apr 2004
Posts: 1,458
Likes: 14
From: Vinton, Louisiana
Amp Protection Mode? What causes an amp to go into protection mode? All my wires check out, but is there something I'm missing?
I bought one off E-Bay and can't get it to stay out of protection mode. It's a US Acoustics USX1000D 2-channel amp. I'm thinking I may have been had...
I bought one off E-Bay and can't get it to stay out of protection mode. It's a US Acoustics USX1000D 2-channel amp. I'm thinking I may have been had...
Very well could have been had.
Try unhooking the speaker wires and see if it still goes into protection. If it still does, it's toast.
If that's the case, put a DVM on it and test for Continuity or resistance from GND/PWR to the speaker leads. That can narrow down where it is fried. (No power or GRN hooked up though.)
Try unhooking the speaker wires and see if it still goes into protection. If it still does, it's toast.
If that's the case, put a DVM on it and test for Continuity or resistance from GND/PWR to the speaker leads. That can narrow down where it is fried. (No power or GRN hooked up though.)
Alright. Protection modes are caused by a couple of things:
1.) Speaker leads shorted against each other or to GND/PWR
2.) Too low of a load. (I.E. can only handle a 1 ohm stereo and you have it in 1 ohm mono)
3.) Too low of an input voltage.
4.) A short in the Input stage. (internal on the AMP.)
You can also open the AMP up and take a good visiual look inside. I've seen all types of goofy **** inside amps before, BUT if you bought it new, don't do this.
Once I had a guy bring in his stereo amp because it was doing the same thing. Turned out that a Jewler's screw driver got inside it and was shorting things out. That amp was fried beyond repair and had burned the carpet a bit.
1.) Speaker leads shorted against each other or to GND/PWR
2.) Too low of a load. (I.E. can only handle a 1 ohm stereo and you have it in 1 ohm mono)
3.) Too low of an input voltage.
4.) A short in the Input stage. (internal on the AMP.)
You can also open the AMP up and take a good visiual look inside. I've seen all types of goofy **** inside amps before, BUT if you bought it new, don't do this.
Once I had a guy bring in his stereo amp because it was doing the same thing. Turned out that a Jewler's screw driver got inside it and was shorting things out. That amp was fried beyond repair and had burned the carpet a bit.
Thread Starter
Joined: Apr 2004
Posts: 1,458
Likes: 14
From: Vinton, Louisiana
Well, I have to admit I'm an idiot. I thought the "protection mode" LED meant it was in it. Actually a 2 color LED and green is good. red is bad. Sooooo, slamming harder now! Thanks for the input !!!!
Thread Starter
Joined: Apr 2004
Posts: 1,458
Likes: 14
From: Vinton, Louisiana
Re-Wire Subs For MORE Bass?? http://www.usacoustics.com/2004/usx1000d%20specs.htm
Alight, got three 10w3v2-D4s with a 2.7 overall load. Wonder if I'm pushing these 10s enough? What kind of power am I getting out of this amp, seems like I'm getting under 700w for sure? Should I re-wire the subs so I can get a 0.7ohm load and turn the amp down a bit? This way I can squeeze the extra 100w out of each sub for more umph? Am I right in thinking this way?
What would you suggest my best route to go be?
THANKS!
Alight, got three 10w3v2-D4s with a 2.7 overall load. Wonder if I'm pushing these 10s enough? What kind of power am I getting out of this amp, seems like I'm getting under 700w for sure? Should I re-wire the subs so I can get a 0.7ohm load and turn the amp down a bit? This way I can squeeze the extra 100w out of each sub for more umph? Am I right in thinking this way?
What would you suggest my best route to go be?
THANKS!
Douh. I've made simple mistakes myself. lol
A load is independant of the Input level. So, you really can't just turn it down.
Gains control the input signal by either; A.) Boosting the signal, or B.) Attenuating the signal. It doesn't control the way the amplifier see's a load.
I don't know what that amp can do, so I'll have research a little.
Ok. It's a MONO amplifier, not a 2 channel. Might have speaker Terminals to make you think it's 2 channel, but they are just extra spots that still go to 1 point.
It is good for a 1ohm mono load so 0.7ohm's will be OK at this point. The Resistance of a speaker changes based on the type of enclosure, and the actuall measurement of Re. (They are Thiel-Small parameter's. http://www.ishtek.com/spkr_small.htm)
It is not a straight flat 4 ohm load (using 4 ohm's here as an example), but rather a curve that can range from 3.2 ohms to as high as 6 ohm's.
Here is just a random speaker I found that show's a good graph.
http://www.speakercity.com/Merchant2..._Code=P1CSCCSX
So, depending on the speaker and how it is loaded (how it react's in a box), the actual resistance can vary. So even though you get a 0.7 ohm load, it is usually higher than that.
Based on my experience, you should be fine so long as the speakers can handle it, and the amplifier doesn't get to hot. Turning the gain's down (attenuating the signal) will present a lower level signal to amplify and can keep it from getting too hot, BUT it is still a low load and the amplifier will use more current. That is why it get's hotter.
A load is independant of the Input level. So, you really can't just turn it down.
Gains control the input signal by either; A.) Boosting the signal, or B.) Attenuating the signal. It doesn't control the way the amplifier see's a load.
I don't know what that amp can do, so I'll have research a little.
Ok. It's a MONO amplifier, not a 2 channel. Might have speaker Terminals to make you think it's 2 channel, but they are just extra spots that still go to 1 point.
It is good for a 1ohm mono load so 0.7ohm's will be OK at this point. The Resistance of a speaker changes based on the type of enclosure, and the actuall measurement of Re. (They are Thiel-Small parameter's. http://www.ishtek.com/spkr_small.htm)
It is not a straight flat 4 ohm load (using 4 ohm's here as an example), but rather a curve that can range from 3.2 ohms to as high as 6 ohm's.
Here is just a random speaker I found that show's a good graph.
http://www.speakercity.com/Merchant2..._Code=P1CSCCSX
So, depending on the speaker and how it is loaded (how it react's in a box), the actual resistance can vary. So even though you get a 0.7 ohm load, it is usually higher than that.
Based on my experience, you should be fine so long as the speakers can handle it, and the amplifier doesn't get to hot. Turning the gain's down (attenuating the signal) will present a lower level signal to amplify and can keep it from getting too hot, BUT it is still a low load and the amplifier will use more current. That is why it get's hotter.
Thread Starter
Joined: Apr 2004
Posts: 1,458
Likes: 14
From: Vinton, Louisiana
Ahhhh.... Learning! Makes WAY more sense now. So since my W3v2s are DVC, I'll wire them in parallel instead of series as to get my 0.7ohm load. Then since the specs on the amp say that it "should" deliver a 1250w output at 1ohm. Which means to keep my speakers in their range of use, I will need to turn the amp down about 1/4. Of course, hearing them will help me judge about where I'll need the amp set on as to get no distortion.
Not sure if the amp will get hot enough to clip. It's under my box now and is inclosed. So I know it's definitely possible! Would you suggest me getting a fan for it to circulate the air. I know it'll be circulating hot air, but it might be better than still hot air..
Also got enough current, I think. See the pics below and please excuse the dust.
1/0 from battery to fused dist., then 1-4ga and 2-8ga wires out of that back to the 3 amps. I know I could have simplied it, but I initally started with one 10w0, then it went from there to where I am now...
Not sure if the amp will get hot enough to clip. It's under my box now and is inclosed. So I know it's definitely possible! Would you suggest me getting a fan for it to circulate the air. I know it'll be circulating hot air, but it might be better than still hot air..
Also got enough current, I think. See the pics below and please excuse the dust.
1/0 from battery to fused dist., then 1-4ga and 2-8ga wires out of that back to the 3 amps. I know I could have simplied it, but I initally started with one 10w0, then it went from there to where I am now... 
