weird nagging problem
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It's a wooden pickle.
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weird nagging problem
this isn't something i've ever run into, and rather than pulling my whole system apart and troubleshooting it, i figured i'd post in here and see if anyone had run into it before and had a solution...
whenever i first turn my car on, my subs don't play at all. no sound whatsoever. once i turn it up to my normal listening volume, sometimes they'll kick right in, and sometimes there will be a long delay. sometimes they don't cut in at all unless i jack the volume up past what i normally listen to.
what could that possibly be? i was thinking it would have to be something going on with the sub amp... it's an alpine mrd-m650. i know the HU and remote wire are fine because the same wire kicks the full-range 2ch on no problem. but anyways i was just curious if anyone knew what was going on or if there was an easy fix for it.
whenever i first turn my car on, my subs don't play at all. no sound whatsoever. once i turn it up to my normal listening volume, sometimes they'll kick right in, and sometimes there will be a long delay. sometimes they don't cut in at all unless i jack the volume up past what i normally listen to.
what could that possibly be? i was thinking it would have to be something going on with the sub amp... it's an alpine mrd-m650. i know the HU and remote wire are fine because the same wire kicks the full-range 2ch on no problem. but anyways i was just curious if anyone knew what was going on or if there was an easy fix for it.
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Here's a stab in the dark...
Some amps use what is called a noise gate. Basically, when the input level is very low, the output is disabled. This was done as a band aid for gain hiss, and other noises that only show at very low volumes. These were huge back in my IASCA days, since noise cost you points. From memory, Alpine was one of the first to use this technology in their amps.
So, if this circuit is present, it might not be kicking in at the normal low volume level, but it does when you turn it up. If this is the case, I don't know how to test for it, and it probably means a new amp. You could see if Alpine will admit to using a gate, for starters. Even if it has one, they might not tell you, though.
Checking the remote voltage, or better yet, jumping it from the B+ of the amp couldn't hurt, although I don't see how turning the volume up would compensate for low turn on voltage. Unless the amp also has some sort of input sensing, like for high level applications, and that is taking over.
Toby
Some amps use what is called a noise gate. Basically, when the input level is very low, the output is disabled. This was done as a band aid for gain hiss, and other noises that only show at very low volumes. These were huge back in my IASCA days, since noise cost you points. From memory, Alpine was one of the first to use this technology in their amps.
So, if this circuit is present, it might not be kicking in at the normal low volume level, but it does when you turn it up. If this is the case, I don't know how to test for it, and it probably means a new amp. You could see if Alpine will admit to using a gate, for starters. Even if it has one, they might not tell you, though.
Checking the remote voltage, or better yet, jumping it from the B+ of the amp couldn't hurt, although I don't see how turning the volume up would compensate for low turn on voltage. Unless the amp also has some sort of input sensing, like for high level applications, and that is taking over.
Toby
Thread Starter
It's a wooden pickle.
Joined: May 2002
Posts: 14,528
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Checking the remote voltage, or better yet, jumping it from the B+ of the amp couldn't hurt, although I don't see how turning the volume up would compensate for low turn on voltage. Unless the amp also has some sort of input sensing, like for high level applications, and that is taking over.
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im thinking you dont have the remote turn on wire connected or it isnt getting power and the voltage sensing turn on is what is activating the amp. Since the voltage sensing is made for high level inputs, you have to crank the volume in order for the preamp to put out enough voltage to make it kick in.
check remote wire with an ohms meter like gradeA said.
check remote wire with an ohms meter like gradeA said.
