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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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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1 Answer

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...

2 Answers

I was thinkin bout buyin a planet audio ac2600.2 car amplifier but cant find what gauge power an ground wire it takes and how many watts it puts out 2 channel @2ohms rms. can you help?

Here are your specs. RMS 900 Watts Nominal and Max 1300 on 2 Channel @ 2 Ohms.
4 Gauge should do fine but if you like to feed the beast go with 2 gauge.
Looks like going rate is $110 on Amazon or elsewhere.
If it attains the RMS wattage it would be a good amp. I like monoblocks but
you will pay more. I looked into Tri-Mode and it is straight forward but people
are having problems figuring it out. With your 2 speaker operation you should
avoid the issues others are having.
Good luck and remember, rearview mirrors were meant to fall off!
Mine: JL 1800A monoblock into 2-JL 12" W3's in series for low bass 20-80 Hz; Lanzar Vibe 266 bridged into 2-12" Memphis in series for mid bass 40-200m Hz. 2 guage wire to mononblock-250 amp fused at battery, 4 guage to Vibe w/250 amp at battery.

Anarchy Series 2-Channel Car Amplifier
  • RMS Power Rating:
    • 2 ohms: 900 watts x 2 chan.
    • Bridged, 4 ohms: 1800 watts x 1 chan.
  • Max power output:
    • 2 ohms: 1300 watts x 2 chan.
  • Total Power Output: 2600 watts
  • Pulse width modulated MOSFET power supply
  • Convenient remote subwoofer control
  • LED power (green) and protect (red) indicators
  • Variable Bass Boost 0 to +18 dB
  • Bridgeable Tri-mode operations
  • Chrome-plated connections enhance durability
  • Variable high and low pass crossovers
  • Illuminated logo
  • 3-Way System Protection circuitry (thermal, overload, and speaker short protection)
  • Dual speaker terminals simplify the hookup of multiple speakers
  • Heavy duty aluminum alloy heatsink for extreme heat dissipation
  • Low level high inputs
  • Heavy-duty set-screw terminals
  • Input sensitivity:
    • Low level: 100mV-2V
    • High level: 2V-8V
  • Variable high-pass filter (45-90 Hz, 24 dB/octave)
  • Variable low-pass filter (50-500 Hz, 24 dB/octave)
  • Damping factor: >125
  • Signal-to-Noise Ratio: 102 dB
  • Frequency response: 20-20,000 Hz
  • Dimensions: 15-9/16"L x 10"W x 2-3/16"H
  • 1/0-gauge power and ground wiring is required for installation. Contact us for information regarding a discount on select amplifier kits when purchased together with this amplifier.
  • 1-year Manufacturer's warranty

Mar 19, 2011 | Planet Audio Car Audio & Video

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

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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...

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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

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Settings for a Sony Xplod 1200 watt amp, with two 12 inch subs

What kind of subs are you running? Meaning what brand, what are the ohm, spl and wattage? I'll look up your amp while you get that info to me. Looking forward to helping you:) Thanks!

Apr 08, 2009 | Sony Xplod 1200W Class AB Bridgeable 2-Ch....

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...

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Hi , you need to replace with thick wire , if possible attache fuse or circuit trip overload protection you may ask to thew radio store .

May 07, 2008 | Polk Audio EX12 Car Speaker

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

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