Audio question...need advice.

Alright, I decided it is time to give my Firebird some needed TLC.

This is for my FIrebird but imagine the rear speakers are the rears in our VX

The previous owner seemed to have used the WalMart special in terms of amps and subs for the car. They had 3 small 5-6inch subs, two in the back seats and one in the rear trunk panel.

MY QUESTION is...is there a way or did they designate the rear back seat speakers to ONLY produce bass? I just put in a new 3-way JB speaker back there and it will only and midly produce bass/low tones. NOTHING else! Is there something that they did with the STOCK radio that has allowed only bass to come through the back seat speakers? At the ear level and with the small size of space back there I really do not want subs I would rather have clean audio from that location.

Please advise.

Are the rear speakers driven directly from the head unit or do they go through an amp?

If they are driven directly from the head unit, then there is probably something wrong with the head unit or it may be set to drive all bass. Try turning up the treble & see if you get anything. Also try adjusting the fader since it may be set to have everything go to the rear & the treble is being under driven.

If the rear speakers are driven by a sub, the sub(s) may have a low pass filter built in. That would only allow the bass to be fed to the speakers.

Also keep in mind that the speakers themselves can act as a low pass filter. If the speaker is designed for bass, then the treble content ends up acting almost like a DC offset. You'd only hear the bass & even that would be degraded due to that DC offset. The opposite would hold true as well (a speaker designed only for treble can not put out bass). That's why crossover networks are important in high end systems.