Amp powers up up fine and plays.But once you start putting a load on it the light flashes from red to green and so on.Its obviously cycling in and out of protect.When it cycles it drags the voltage very low.Seems something is intermediately causing excessive current draw.Any ideas?
We've tried the amp on a power supply and in a vehicle with more capacity than needed.Voltage stays above 13 as it sits there and plays then all of a sudden starts cutting out randomly.
Does it do it with a different speaker?
If you lower the volume, does it continue to cut out?
If you remove all speaker wires from the amp but leave the volume high, does it cut out?
If you lower the volume, does it continue to cut out?
If you remove all speaker wires from the amp but leave the volume high, does it cut out?
Tried different speakers.It only starts to cut out when a few amps are being drawn.I did turn it all the way up without a speaker and I don't believe the light flickered.
You stated that it drags the voltage very low and also stated that the voltage remains above 13v. Which is correct?
How much current is it drawing when it cuts out?
How much current is it drawing when it cuts out?
Okay....the voltage is fine.Once we hit about 5 amps(still above 13 volts) as its playing it'll start to randomly cycle from green/red.When it cycles it starts drawing excessive current which is bringing down the voltage.
Could it possibly have a defective output fet that's just not shorted?Not allowing the amp to drive full load?
Hi Triviumfan,
I think Perry's process of analysis is right on point. I'm using two of the exact same amp and they'll endure much abuse even at 11V; never seen them in "protect mode". Sounds like there may be a direct short across the output terms. Have you replaced the speaker wires to eliminate the possibility of a shorted cable?
rigtec, cheers
Can't be a short.It plays music just fine until u start turning up the volume per say.Once u start putting a load on the amp it cycles protect really fast then plays for a second then cycles again.And its not voltage issue from my power supply or vehicle wiring or speaker issues.I've eliminated all of those things by trying multiple speakers and power.
And what do you think an amp would do if you allowed a few strands of speaker cable to join the pos and neg poles?
I don't understand what your getting at.This thing has removable terminals.I had the terminals removed and used alligator clips at one point and it still kept doing it.Also,if it was shorted how would it play music/sine wave in the first place?
It's possible for an amp to play when there is a short when the wire or whatever is shorting between the terminals isn't a perfect conductor and has some resistance. Significant current flows through the wire strands but there is still enough voltage being produced to allow the speaker to produce audio.
Imagine having a 1 ohm dummy load and an 8 ohm speaker connected to an amp that is only designed to drive a 2 ohm load. The amp would play into the load at low volume and the speaker would produce audio but as you increase the volume, the over-current protection would engage.
How much current is it drawing when it cuts out?
To clarify something that you wrote earlier... You stated that it cuts out once you start putting a load on it. The load is the speaker or dummy load connected to the speaker terminals. I think that you meant .. once you start to drive a signal into the amp when it has a speaker connected. Correct me if that's not what you meant.
Will it cut out if driven hard with no speaker wires connected to the amp?
I had a Rockford amp that would go into protect when driven, even with no speakers connected. The current draw made it appear that a load was connected, even when there was no load. There was a single strand of wire that worked its way under the terminal block and was shorting between the terminals.
Imagine having a 1 ohm dummy load and an 8 ohm speaker connected to an amp that is only designed to drive a 2 ohm load. The amp would play into the load at low volume and the speaker would produce audio but as you increase the volume, the over-current protection would engage.
How much current is it drawing when it cuts out?
To clarify something that you wrote earlier... You stated that it cuts out once you start putting a load on it. The load is the speaker or dummy load connected to the speaker terminals. I think that you meant .. once you start to drive a signal into the amp when it has a speaker connected. Correct me if that's not what you meant.
Will it cut out if driven hard with no speaker wires connected to the amp?
I had a Rockford amp that would go into protect when driven, even with no speakers connected. The current draw made it appear that a load was connected, even when there was no load. There was a single strand of wire that worked its way under the terminal block and was shorting between the terminals.
I'm testing again right now.I drove the amp until clipping with a scope and no speaker connected and it did not go into protection.I'm testing again with a speaker now.For what it worth.I tested the amp with a speaker and alligator clips.This amp has removable terminals so I eliminated possible wire strands.Since my mind is fresh again I'm giving it another shot.Will post back soon..Thanks for the in depth reply
As I mentioned in my first statement, I'm using the same amp (HD-750/1). Whenever I'm working on the amps/wiring, which are located under the driver seat, seems no matter how careful I am, I'll always find some loose copper strands in the carpet, in the "track-well" underneath the seat; they seem to migrate there.
Just a suggestion. Before you insert the speaker terminal disconnect block into the socket, look very carefully (using a good light) inside the socket. There may be foreign matter e.g., copper strands, metal shards, etc... lodged inside the housing or embedded on the front of the male plug, regards.
Just a suggestion. Before you insert the speaker terminal disconnect block into the socket, look very carefully (using a good light) inside the socket. There may be foreign matter e.g., copper strands, metal shards, etc... lodged inside the housing or embedded on the front of the male plug, regards.
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