Hello all,

This has been cross posted to TalkAudio however I never get a response there so hoping maybe someone can offer me some advice

Basically the Alfa I purchased I have inherited a stereo system.

I've replaced the head unit with a JVC unit, however I'm still a little unhappy with the sound quality and complete lack of bass, and a pretty bad rear bias

The current set up is this:

Front Speakers : Infinity 5010CS (13cm speakers that replaced the original 5x7s)

Rear Speakers : Orion P6.2 (6.5 Inch Components + Tweeters) The crossover seems to be missing from these so I think the tweeters are now dead

The Sub The final piece in this Jigsaw is a 8 Inch sub, mounted on the parcel shelf effectively in free air! I believe this is a Direct Audio 8inch dual voice coil job. I have attached a photo for you guys. It's driven by a "Radioactive" Ground Zero GZRA 2100X amplifier. With these specs apparently:

2 x 85W @ 4 ohm
2 x 125W @ 2 ohm
1 x 170W @ 4 ohm bridged
THD: <0.04
S/N Ratio: >90dB
Channel Separation: >60dB
Freq. Response: 10Hz ~ 30kHz (+/- 1dB)

So guys any ideas where to start with this setup? The GTV boot is very small so maybe thats an effective box? (I'm a newbie when it comes to subs etc) The GTV also has a steal firewall between the passenger compartment and boot. Maybe I should ditch the sub and just get some better rear speakers? I'm willing to spend some money (Max £200) However if I can make this system better for free then even better!










Thanks in advance

Ben

P.s. This system was installed by a local car audio firm!

Hello Ben,

First of all, I am no expert!

Have you tried driving the sub on it's own? How loud is it in the car compared with standing at the back with the boot open?

As for sound quality, my advice would be to start off by experimenting with the fader & balance controls a little. Concentrate on the components and forget about your sub bass. Try to find out what sounds good and what doesn't. Is it just the front set or the back set? Maybe they're all bad!?

So if you can, start playing a CD with an assortment of your favourite tracks (or plug in your ipod). Turn down the sub so it is completely off.

Also, check that your speakers are in phase...
Adjust fader to one extreme so that all you can hear are the front speakers (these are the most important). Listen carefully and shift the balance from centre to fully left and then back to centre. Repeat, to the right speaker...
Does the music sound more weighty with both speakers on or does it sound beefier with just one? If it's better on one alone then they're likely out of phase due a wiring error.
Repeat for the rear speakers.

Sounds like you need to fiddle around with the settings a little. With the sub sat in the shelf as it is, it is totally out of it's correct dimesions, so that's the reason for lack of bass.

Get it in a small ported box to give you that deep punch effect.

As for the speakers, follow barneys instructions, and start with the speaker setting's.

May also need to turn the gain up on the amp for the sub?