Sound cutting in and out...
03-22-2011, 08:34 PM
#11
500 Watt CAFz'r
Thread Starter
Join Date: May 2007
Posts: 849
I emailed MTX and this is what they said:
"That is really strange. It sounds like something is getting fatigued in the
amplifier. I would say a voice coil could be getting hot or beginning to
fail, but that would either only effect that speaker or it would put the amp
into protection. If it was a voltage issue, the problem would be worse when
the volume is up, but you can test the dc voltage at the amp with a
multimeter if you want to be sure. The voltage should stay at or close to
the charging voltage of the alternator. At the very least it should not drop
below 12.5v (floating voltage of the battery). If that looks ok, I would
suggest having a shop check it out, or calling our Canadian dept at
800-663-2511 to ask about sending it in."
Now it happened again tonight but just once after cranking it for at least 30 minutes. The sound faded out fast and then waited about 1 second and faded back in. Strange...It doesn't just cut right it sounds like it faded in and out instead of just stopping on a dime.
Again I checked the amp for physical heat and it was warm and not really hot. I've driven amps to where it be too hot to touch with no problems.
Looks like I have might have to send this amp back...
"That is really strange. It sounds like something is getting fatigued in the
amplifier. I would say a voice coil could be getting hot or beginning to
fail, but that would either only effect that speaker or it would put the amp
into protection. If it was a voltage issue, the problem would be worse when
the volume is up, but you can test the dc voltage at the amp with a
multimeter if you want to be sure. The voltage should stay at or close to
the charging voltage of the alternator. At the very least it should not drop
below 12.5v (floating voltage of the battery). If that looks ok, I would
suggest having a shop check it out, or calling our Canadian dept at
800-663-2511 to ask about sending it in."
Now it happened again tonight but just once after cranking it for at least 30 minutes. The sound faded out fast and then waited about 1 second and faded back in. Strange...It doesn't just cut right it sounds like it faded in and out instead of just stopping on a dime.
Again I checked the amp for physical heat and it was warm and not really hot. I've driven amps to where it be too hot to touch with no problems.
Looks like I have might have to send this amp back...
Last edited by d4rin; 03-22-2011 at 08:38 PM.
03-23-2011, 08:04 PM
#12
500 Watt CAFz'r
Thread Starter
Join Date: May 2007
Posts: 849
BUMP...
Ok I did some more testing tonight, I cranked it for awhile and turned down the volume. I lowered the rear seats so I could see if the LED blinks or not.
When I turned the volume down the LED's faded in and out twice, So I turned up the volume again and then down again. The LED's faded in and out again...
This only happens when I crank it and then turn it down, I don't get it? It's like the amp shuts off and on really fast when I turn the volume down. I thought it was a signal problem but it seems to be a power problem, Either the amp is a dud or it's a voltage problem.
This is what it says in the manual:
7. Amplifier shutting off and LED flashing off and on:
high voltage at the +BATT or the remote portion of the amp. Test the +BATT and the remote
portion of the amp with a digital multi-meter. If the voltage at either of these terminals is
above 15 volts or below 11 volts, consult an automotive electrical specialist. If voltage is
consistently below 11 volts, adding a one-farad StreetWires stiffening capacitor will solve the
problem.
But the amp only shuts off for probably half a second and turns back on hence why the LED's barely blink.
Once I check the voltage and if it's normal than this amp is a dud and I'm sending it back...
Ok I did some more testing tonight, I cranked it for awhile and turned down the volume. I lowered the rear seats so I could see if the LED blinks or not.
When I turned the volume down the LED's faded in and out twice, So I turned up the volume again and then down again. The LED's faded in and out again...
This only happens when I crank it and then turn it down, I don't get it? It's like the amp shuts off and on really fast when I turn the volume down. I thought it was a signal problem but it seems to be a power problem, Either the amp is a dud or it's a voltage problem.
This is what it says in the manual:
7. Amplifier shutting off and LED flashing off and on:
high voltage at the +BATT or the remote portion of the amp. Test the +BATT and the remote
portion of the amp with a digital multi-meter. If the voltage at either of these terminals is
above 15 volts or below 11 volts, consult an automotive electrical specialist. If voltage is
consistently below 11 volts, adding a one-farad StreetWires stiffening capacitor will solve the
problem.
But the amp only shuts off for probably half a second and turns back on hence why the LED's barely blink.
Once I check the voltage and if it's normal than this amp is a dud and I'm sending it back...
03-25-2011, 12:55 PM
#15
500 Watt CAFz'r
Thread Starter
Join Date: May 2007
Posts: 849
03-25-2011, 12:55 PM
#16
500 Watt CAFz'r
Thread Starter
Join Date: May 2007
Posts: 849
03-25-2011, 01:12 PM
#17
500 Watt CAFz'r
Thread Starter
Join Date: May 2007
Posts: 849
JohnVroom - I read this about Voltage Overshooting and I find this interesting because the stock cables for the batter are probably only 8awg and I haven't upgraded any of that yet.
"Voltage wave reflection occurs when the impedance on either end of the cable run does not match, causing voltage pulses to be reflected back in the direction from which it arrived. As these reflected waves encounter incoming waves, their values can add, causing higher peak voltage."
I think there's a higher chance of the problem being my electrical system than the amp. I'm just using the stock battery and stock cables under the hood and it's a decent size amp.
"Voltage wave reflection occurs when the impedance on either end of the cable run does not match, causing voltage pulses to be reflected back in the direction from which it arrived. As these reflected waves encounter incoming waves, their values can add, causing higher peak voltage."
I think there's a higher chance of the problem being my electrical system than the amp. I'm just using the stock battery and stock cables under the hood and it's a decent size amp.
03-25-2011, 07:37 PM
#20
Yankee
Join Date: Oct 2003
Posts: 3,599
JohnVroom - I read this about Voltage Overshooting and I find this interesting because the stock cables for the batter are probably only 8awg and I haven't upgraded any of that yet.
"Voltage wave reflection occurs when the impedance on either end of the cable run does not match, causing voltage pulses to be reflected back in the direction from which it arrived. As these reflected waves encounter incoming waves, their values can add, causing higher peak voltage."
I think there's a higher chance of the problem being my electrical system than the amp. I'm just using the stock battery and stock cables under the hood and it's a decent size amp.
"Voltage wave reflection occurs when the impedance on either end of the cable run does not match, causing voltage pulses to be reflected back in the direction from which it arrived. As these reflected waves encounter incoming waves, their values can add, causing higher peak voltage."
I think there's a higher chance of the problem being my electrical system than the amp. I'm just using the stock battery and stock cables under the hood and it's a decent size amp.
I agree this appears to be a power supply issue, and one where it is the electrical system is the problem not the system. The clamp on is the wrong tool as it will tell you what you already know (the amp is cutting out), a voltmeter will tell you what kind of over/under voltage your amp is seeing causing it to momentarily shut down (I am guessing voltage is peaking as you turn it down).
