Question about Legacy Audio LA770 Car Audio Amplifier

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Legacy amp 1200 watts

I have 2 amps conected and some times when a heavy bass line drops it puts 1 of my amps into protect mode while the other amp is ok and still running my speakers can any 1 help me solve this problem?

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Re: legacy amp 1200 watts

I have had the exact same problem with the exact same lagacy amp that you have posted, put your ground in a different spot or try double grounds in two different spots this should solve your problem here. good luck

Posted on Oct 06, 2006

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I have 2 12in kenwoods and a 1200 watt pyrimade amp, how can i hook these up to be the loudest

1st have your subs facing inwards towards the front of the car, not facing out the boot, This creates a better bass.

Wire 1 sub to one channel and the other sub to the other channel.

Turn down your gain as low as possible and then power everything up.

turn volume to desired loudness and then start turning up the gain slowly, if distorts a little turn in back down a notch.

avoid using bass boost, I agree it sounds great but it puts more strain on your amp and shortens its life.

after sorting out your gain, tweak all others until sound is bassy and clear with no distortion.

If you would like to use bass boost, turn on bass boost first, then up your gain etc.

Jan 16, 2013 | Pyramid PB915X 1200 Watts 2 Channel...

1 Answer

Legacy LA770 worked for 2 10" subs but not for 1 12" sub

if the protect light is still on with all speakers disconected then you have overloaded the internal ic and blown it beyound its ability to reset


Jun 25, 2010 | Legacy Audio LA770 Car Audio Amplifier

2 Answers

Legacy audio LA590 car audio amp protecet mode

Is that on all the time or are you saying the light is on? If that light is always on that just means it's protecting your amp. If it's off and not playing bass then your in trouble

Mar 01, 2010 | Legacy Audio American Legacy II LA590 Car...

1 Answer

LA-1030 Protect Mode

you have an unloaded channel,so the voltage is exceeding what the protect circuit is supposed to have to connect an 8 ohm resistor across the output of the unused channel.
do not drive a signal into it or you will smoke the resistor.
a 10 watt will do ok with zero signal input

May 23, 2009 | Legacy Audio LA1030 Car Audio Amplifier

1 Answer

Subs and amp problem

2 subs and 1 amp

Nov 16, 2008 | Car Amplifiers

2 Answers

600w legacy amp

9 times out of 10 if your amplifire is in protect mode and evrything externaly, like speakers, fuse, voltage, etc. checks out fine then
either you have shorted out output transistors or power mosfet transistors. Basicly that just about what happens with car amps.
It's easy enough to fix IF, IF you know what your doing. First you
need to check the output transistors with a digital volt meter on diode check, If they check out then check your power supply mosfet transistors. I can almost guarantee this is your problem. Very common. I buy non working amps all the time and repair them. Listen to pbabin also he has helped me out. Good luck

Sep 08, 2008 | Legacy Audio American Legacy II LA490 Car...

1 Answer

My Amp

sounds like the sub that throws it into protect mode is cross wired pull sub out and make sure they are wired right make sure ground from sub goes to ground on box and do same for power wire

Jun 11, 2008 | Sony Xplod Car Audio Amplifier XM-DS1300P5...

1 Answer

Optimum sound performance needed

1) legacy products are highly overrated and i have never seen one put out the power it claims
2) if you are running the amp bridged, you need to match the impedance of the speakers to the amps highest output impedance, otherwise your system will not sound all that great...

what size fuse or fuses does your amp use? what size wire did you install with (power and ground)? did you connect direct to battery or did you connect to a fuse block or similar? did you use a stiffening capacitor? does it sound like it is clipping when you turn it up or is it just distorted? what kind of box are you using for the speakers (ported, vented, sealed, bandpass)?

if you give me the model number of your speakers and your amplifier i can probably help you more, but with the information you have provided, this is all i can offer..

hope it helps,

Nov 11, 2007 | Legacy - American II: 2 Channel 2000W...

1 Answer

Protection mode override

If you have your subs wired to the amp in a bridged configuration, try wiring one to each stereo channel instead. Also, make sure your ground wire is secure and connected to a clean, solid metal part of the vehicle body with the paint scraped off. If this doesn't work, disconnect both subs and try connecting only one at a time; one of the subs may have a problem that is shutting down the amplifier.

Mar 11, 2007 | Sony XM-2002GTR Car Audio Amplifier

2 Answers

Legacy 1200 watts

First thing to look for would be pinched speaker wires,or a bad ground, or a loose b+ wire. The next would be to have the amp bench tested and the tech should bang and tap on the unit to see if there are bad or cold solder connections inside on the printed circuit board assy.

Sep 08, 2006 | Legacy Audio LA770 Car Audio Amplifier

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