Ok some thoughts:
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1- The SW1600 a well regarded under seat compact active sub.
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However it is
a compact unit and it can not be expected to perform aswell as a full size boxed
8/10/12inch sub
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+ amp.
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It is simply not possible to get the same low frequency extension
and amplitude from a compact version.
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That said, it provided considerable extra bass to the stock mr2 speaker system.
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The mr2 is not a quiet car and most of us have louder exhausts, so expect to loose
a fair amount of extra bass when driving since road noise
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& exhaust boom is in the
same frequency range.
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So considering the above, lets look at the active sub input connections.
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HI_LEVEL inputs are designed to be connected to the speakers themselves, voltage
here can approach battery volts.
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Advantage
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- you can use these inputs on any system
since you are connecting directly to the loudspeakers themselves, disadvantage
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- since
you are connecting after the amplifier you potentially loose quality through the HU main amp.
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Also any tone control you set will appear on the HI_level which you dont want since can overdrive.
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LO_LEVEL
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/ RCA
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/ Phono are designed to be connected before the main amp on the HU hence
maximum signal quality.
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Typically a MAXIMUM of 1v
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( ish)
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So you need to be careful where you
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plug these in, just trying each jack not really advised
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- your HU may have non standard output levels
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?
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Onto practical suggestions:
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A.
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Turn all BASS settings to flat- 0.
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Turn loudness OFF
With bass cranked up and loudness on from the HU,
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its possible this is overdriving the input to the sub and the
crackle you hear is clipping.
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B.
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On your head unit, there is likely to be a menu option to set OUTPUT LEVEL on SUB and PRE-AMP outputs.
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Set these mid way
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( not maximum
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- this is likely to clip the volume
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)
Its always best to start at the lower levels and gradually raise the levels before any distortion or clipping occurs.
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Again on the sub itself start low on GAIN and gradually increase the level and throttle back if you hear distortion.
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C.
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There is a L
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& R input to the sub, if you only connect one connection you may only get 1/2 amplitude or less.
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You need
both(L+R) connected.
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( But do not connect HI and LO level inputs simulataneously
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)
If you use HI-level inputs and accidently reverse one set of connections, you will loose nearly all bass since one channel will
cancel out the other one.
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D.
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Battery positive lead
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- does this run via a fuse to the battery
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+ itself
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? If you are connecting off something else this
may not be full battery volts and hence may not supply the current needed.
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E.
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Ground lead
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- the same, is this a good connection to chassis ground.
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Ideally short as possible with a good clean
metal to metal chassis connection.
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*NOTE
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- the unit will turn on and off fine with poor connections, you will only see the effect when current is drawn
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( ie bass
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)
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F.
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Battery ok and fully charged
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?
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G.
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DSP settings, does your HU have any DSP settings
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?
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Some units reduce bass to the front speakers so your L
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+ R pre amp outs
may be not getting the full signal.
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Check any other settings like ROCK/POP/CONCERT etc.
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.
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are set OFF
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Hope some of these suggestions help, you were not sold a dud
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- just there are many factors to consider when you install something like this.
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Regards