lanzar amp problems
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From: the woodlands tx
Turn the "gain" or "level" or "sensitivity' **** down to zero. Then turn the volume on your head unit up all the way until just before your speakers distort. Then, with the speakers playing loud, slowly turn the "gain" on your amp up until just before the subs distort or bottom out. Then, turn down the volume of your head unit to a reasonable level.
For now your gain is set. While this isn't the most proper way to set your gains, its a rough estimate and should keep it safe for now. I'd do this before you damage anything.
Oh, and DONT TOUCH the bass boost. Thats asking for trouble.
If your subs are ported, set the subsonic filter to the tuning frequency of your box. If your box is sealed, set the subsonic to 20Hz.
For now your gain is set. While this isn't the most proper way to set your gains, its a rough estimate and should keep it safe for now. I'd do this before you damage anything.
Oh, and DONT TOUCH the bass boost. Thats asking for trouble.
If your subs are ported, set the subsonic filter to the tuning frequency of your box. If your box is sealed, set the subsonic to 20Hz.
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From: Seabrook,NH
Its sensitivity. The higher the gain, the higher the sensitivity the speakers. The higher the sensitivity, the more likely you are to get distortion/clipping. When your subs clip...your amp shuts down (protect mode) to help save your speakers from blowing. There is usually no reason for your gain to be past 50%.
Think of it this way: If the HU output maxes out at 2 volts before clipping you want your amp to produce its max output with a 2 volt input. If the gain is set for a 3 volt input you will not get all the performance you paid for from that amp. Now some will set an overlap as you are never listening to full volume signal all the time. Some do 3 db, some do more.
Speaker sensitivity is a design issue taken care of by the speaker manufacturer.
Muddy, Ideally you should find where your head unit output clips first before adjusting the amp gain. Set your head unit just below clipping and then turn up the gain on the amp until it just starts to clip and back it down (unless you are setting an overlap but that is a more detailed discussion).
You should check for clipping using test tones and a scope but you can do it by ear as well but be aware that it doesn't take much to damage the speakers that way.
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From: Scottsdale, Arizona
Not quite but close enough. It does not change the sensitivity of the speakers, it changes the amp's sensitivity. It matches the input of the amp to the output of the HU line outs.
Think of it this way: If the HU output maxes out at 2 volts before clipping you want your amp to produce its max output with a 2 volt input. If the gain is set for a 3 volt input you will not get all the performance you paid for from that amp. Now some will set an overlap as you are never listening to full volume signal all the time. Some do 3 db, some do more.
Speaker sensitivity is a design issue taken care of by the speaker manufacturer.
Muddy, Ideally you should find where your head unit output clips first before adjusting the amp gain. Set your head unit just below clipping and then turn up the gain on the amp until it just starts to clip and back it down (unless you are setting an overlap but that is a more detailed discussion).
You should check for clipping using test tones and a scope but you can do it by ear as well but be aware that it doesn't take much to damage the speakers that way.
Think of it this way: If the HU output maxes out at 2 volts before clipping you want your amp to produce its max output with a 2 volt input. If the gain is set for a 3 volt input you will not get all the performance you paid for from that amp. Now some will set an overlap as you are never listening to full volume signal all the time. Some do 3 db, some do more.
Speaker sensitivity is a design issue taken care of by the speaker manufacturer.
Muddy, Ideally you should find where your head unit output clips first before adjusting the amp gain. Set your head unit just below clipping and then turn up the gain on the amp until it just starts to clip and back it down (unless you are setting an overlap but that is a more detailed discussion).
You should check for clipping using test tones and a scope but you can do it by ear as well but be aware that it doesn't take much to damage the speakers that way.
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From: Aiken, SC
well even with the gain a little under half way up it still clips when the truck is running. but i can turn the gain completely up if the truck isnt running and it will play it fine can someone explain that?
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From: Seabrook,NH
You have more voltage when the truck is running. Typically ~14.4 volts from the alternator. When you are not running you get about 12.6 from the battery. Your system is not getting or giving as much power. Your gains are not set correctly and you are causing the amp to go into protection.
Last edited by Norm; Feb 11, 2010 at 03:32 PM.
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From: Aiken, SC
i have to set the gain at barely a 1/4 of the way up so it doesnt cut out though. and its not halfway as loud as it could be with the gain halfway up and the truck off. i guess i just need a different amp i am not very satisfied with this one at all.
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From: Seabrook,NH
What frequency is the low pass set to on the amp and the HU? Is the sub out on the HU set up correctly? That amp should be plenty loud at the 1 ohm load you are giving it. Something is not setup right. Take it to a local installer and have it checked out.
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From: Aiken, SC
im not sure what number the low pass is on on the amp but its almost as low as it can go. dont have a low pass on the head unit.the particular cd player i have has weird looking rca outputs though now that i think about it. its like a kind of metal plug that goes into the cd player then has wires and then the female rca connectors. not sure if it came like that or not it was like that when i bought the truck. could that possibly have something to do with it?
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From: Northern California
im not sure what number the low pass is on on the amp but its almost as low as it can go. dont have a low pass on the head unit.the particular cd player i have has weird looking rca outputs though now that i think about it. its like a kind of metal plug that goes into the cd player then has wires and then the female rca connectors. not sure if it came like that or not it was like that when i bought the truck. could that possibly have something to do with it?
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From: Seabrook,NH
im not sure what number the low pass is on on the amp but its almost as low as it can go. dont have a low pass on the head unit.the particular cd player i have has weird looking rca outputs though now that i think about it. its like a kind of metal plug that goes into the cd player then has wires and then the female rca connectors. not sure if it came like that or not it was like that when i bought the truck. could that possibly have something to do with it?
What model CD unit is it? If it has a dedicated sub output there will be some settings for it on the CD head unit.
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From: Aiken, SC
well it has 2 or 3 sets actually built in to the cd player and then the set for the tubs that has the pin connector. im not sure of the serial number but its a sony xxplod cd player.there is a subwoofer and a lpf control on the head. but my head unit acts up the screen goes away alot and it pushes buttons on its own sometimes. my rca wires are ran right next to my power wire for now too im thinking this might be the problem. im gonna run a new set on the other side of the truck completely away from the power wire and see if this helps. could that have caused it though? i never really thought about it til now
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From: Seabrook,NH
RCA next to power might give you electronic noise but it will not make your head unit act up. What is the sub lpf and control set on the head unit? What is it set at on the amp? Sounds like you might need a new head unit.