Now it is time to disconnect all other subwoofers or speakers so that you can hear only the
woofer powered by this amplifier. Next, turn the level on the amp all the way down. Choose
some music that you’re not particularly keen on that has a good range of bass, treble and
vocals (helps not to get lost in the music whilst you work on the system.)
Then go to your head unit and gradually turn up the volume until you begin to hear slight
distortion from the subwoofer. This is normally about ¾ the way up the scale. This is the
maximum setting that you will EVER use from now on – make a mental note of it. Next, turn
the head unit down from here by around ¼. This builds in a little bit of “headroom” so should
you have a track that is recorded quieter than the others or is at a lower bit rate, you can
boost the volume without pushing anything into distortion.
Once the volume is set on the head unit, go to the amplifier and slowly start to turn the
“Level” knob up, keep going till it is at a level you are happy with (that isn’t going to deafen
you!) or until your woofer(s) are just about to distort. If they do start to distort, turn back down
till they sound perfectly clear.
One thing that you need to learn is how to actually hear a woofer “distort” – it sounds different
than a full range speaker because rather than hearing distortion in the conventional sense
you will hear it as an unclean bass note – you may hear a cracking, a metallic slapping
sound or a rattle. It is CRITICAL that you detect this sound and back the amp off to stop it
NOW. If you do not perform this step you will become another sad statistic in our “rejected
warranty” book – you will be ringing up in about a week wondering why your woofer or
amplifier is toasted. Don’t be this sad individual!
You will notice that earlier in the text we set the bass boost to off. This is because more often
than not this EQ control is misunderstood and can cause damage. The bass boost control
ramps a range of frequencies in the bass region that will cause more bass to be created
than the signal coming in from the head unit expects. It will also consume more power and
can push a system into distortion if the settings are not made carefully. An example of a valid
use of bass boost might be where your woofer system has an uneven response – as you
turn up the gain the upper region of the output becomes strained and begins to distort but
yet with low frequencies you are able to turn up the bass without distortion. In this case, you
would go back to the beginning of the setup instructions, get the woofer playing at a modest
level and then swing in some bass boost until the distortion happens at the same volume
level, regardless of the music you are playing. Then, you would set the gain with the bass
boost control in THAT position – to take account of that level of boost. You ABSOLUTELY
cannot increase the bass boost once you have already set the gain level – you’ll overdrive
the amplifier and burn something out.
Treat the bass remote with similar caution. It is effectively an overdrive gear – designed to
allow you to fine tune the sound to your preference. It cannot, however, make the system
more powerful than it already is! So yes, as you drive slowly with little tyre noise you might
want to reduce the setting on the cockpit knob to reduce the bass level. And yes, if you are
listening to a track with a low recording level and you fancy a bit more output you might
