I would like to improve the sound in my diesel van, but choosing an
appropriate upgrade path is tough!

Currently, I only have two JBL 4" coaxial in-dash speakers, driven by
a jvc sh99 headunit (4x19rms @0.8%THD, according to the specs). It
sounds Ok in the upper range, even at moderately high listening
volume, but there are absolutely no bass and very weak midbass, as
well as no "punch".

I'm considering the following options, which are in my budget
($200-$300) thanks to some good deals:

option#1: ~$200
installing a descent 10" "Velocity" sub in a box, which I would put in
the rear cargo space, driven by an external blaupunkt GTA 250 amp
(2-channel). The existing JBL speakers would be driven by the
headunit. Quite simple and cheap solution; should extend the low range
nicely and give good puch, but the midbass will still be lacking.

option#2: ~$250
same as option#1, but using the 4-channel GTA 450 amp to power the
front speakers. But these speakers being in dash, I'm afraid that this
solution would not improve things much, because without good
enclosures these speakers would likely not perform better in the
midbass range, and the added amp power will be wasted. am I wrong on
this?

option#3: ~$300
same as option#1 + 2 rear midrange woofers in the backdoors, driven by
a 4-channel amp: 2 channels bridged for the sub, and the remaining
channels powering the woofers (band passed between 100-250hz). This
option is stretching by budget a bit, but should really improve
midbass, without ruining too much the front imaging.

option#4: $170
the cheap, simple and easy one: a compact active subwoofer such as the
clarion srv303 installed under the passenger seat, and that's all.
Should extend the low range, but will it be Ok to handle the midbass
as well? the specs of the srv303 give a frequency response of 30-200hz
(30 seems quite optimistic for such a small box).

What would you recommend me as the most cost efficient solution? and
what would be the best sounding one?
I forgot to mention that I'm not looking for very lound listening
level, but enough to overcome the vehicule noise. I also like well
balanded sound, without over importance of bass.

Thanks for for your advices

Patric

Unless you're willing or able to get larger speakers in the front doors, you
probably won't ever have stellar midbass. But most people don't anyway and
confuse midbass "punch" with good sub punch.

As far as speakers in the rear doors, I personally don't like midbass coming
from behind me. If you get an amp for the front speakers, you won't be
"wasting" it, because it will increase the clarity and volume dramatically
over the HU amp, but your midbass will still be limited by the speaker size.

If it were me I'd try my best to get larger speakers up front. Period.

If this isn't an option, I'd get a 4-channel amp with variable crossovers.
Run the two front speakers off channels 1 & 2 and then bridge 3 & 4 into a
decent sub. Play around with the xovers until you get the best sound.

Tony


--



What's more likely? That an all-powerful mysterious god created the
universe and then decided not to give any proof of his existence? Or, that
he simply doesn't exist at all? And that we created him so that we wouldn't
have to feel so small and alone. -Eleanor Arroway, Contact

"Patrick" wrote in message
om...
I would like to improve the sound in my diesel van, but choosing an
appropriate upgrade path is tough!

Currently, I only have two JBL 4" coaxial in-dash speakers, driven by
a jvc sh99 headunit (4x19rms @0.8%THD, according to the specs). It
sounds Ok in the upper range, even at moderately high listening
volume, but there are absolutely no bass and very weak midbass, as
well as no "punch".

I'm considering the following options, which are in my budget
($200-$300) thanks to some good deals:

option#1: ~$200
installing a descent 10" "Velocity" sub in a box, which I would put in
the rear cargo space, driven by an external blaupunkt GTA 250 amp
(2-channel). The existing JBL speakers would be driven by the
headunit. Quite simple and cheap solution; should extend the low range
nicely and give good puch, but the midbass will still be lacking.

option#2: ~$250
same as option#1, but using the 4-channel GTA 450 amp to power the
front speakers. But these speakers being in dash, I'm afraid that this
solution would not improve things much, because without good
enclosures these speakers would likely not perform better in the
midbass range, and the added amp power will be wasted. am I wrong on
this?

option#3: ~$300
same as option#1 + 2 rear midrange woofers in the backdoors, driven by
a 4-channel amp: 2 channels bridged for the sub, and the remaining
channels powering the woofers (band passed between 100-250hz). This
option is stretching by budget a bit, but should really improve
midbass, without ruining too much the front imaging.

option#4: $170
the cheap, simple and easy one: a compact active subwoofer such as the
clarion srv303 installed under the passenger seat, and that's all.
Should extend the low range, but will it be Ok to handle the midbass
as well? the specs of the srv303 give a frequency response of 30-200hz
(30 seems quite optimistic for such a small box).

What would you recommend me as the most cost efficient solution? and
what would be the best sounding one?
I forgot to mention that I'm not looking for very lound listening
level, but enough to overcome the vehicule noise. I also like well
balanded sound, without over importance of bass.

Thanks for for your advices

Patric

"Tony Fernandes" wrote in message ...

Unless you're willing or able to get larger speakers in the front doors, you
probably won't ever have stellar midbass. But most people don't anyway and
confuse midbass "punch" with good sub punch.

As far as speakers in the rear doors, I personally don't like midbass coming
from behind me. If you get an amp for the front speakers, you won't be
"wasting" it, because it will increase the clarity and volume dramatically
over the HU amp, but your midbass will still be limited by the speaker size.

If it were me I'd try my best to get larger speakers up front. Period.

I see your point. Unfortunately, there no slots in the front doors for
speakers :-(. However, as there is quite a lot of room under the
passenger seat, running a single 6.5" woofer in mono in a good
enclosure would be an option. I would be afraid of unbalancing the
stereo imaging however...


If this isn't an option, I'd get a 4-channel amp with variable crossovers.
Run the two front speakers off channels 1 & 2 and then bridge 3 & 4 into a
decent sub. Play around with the xovers until you get the best sound.

Thank you for your inputs Tony, this option seems the most flexible.

Just another question, as I'm quite a newbie in external amp: At the
same listening level, are the typical external amp use about the same
electrical power as a HU, or more (or less?). I mean, what is the
typical efficiency of HU amp. vs. external amp? I'm thinking about
this as I'm often listening to the music while parked (while working
or in camping trips) without alternator power, so I would like to keep
the battery load quite low if possible.

Thanks!

Patrick

Another good idea is dynamatting the back of your speakers in your
kick panels. Believe it or not, it will get rid of a lot of problems
associated with the speaker slightly moving around in the kick panel
and will increase the mid bass a little

"Just another question, as I'm quite a newbie in external amp: At the same
listening level, are the typical external amp use about the same electrical
power as a HU, or more (or less?). I mean, what is the typical efficiency of
HU amp. vs. external amp? I'm thinking about this as I'm often listening to
the music while parked (while working or in camping trips) without
alternator power, so I would like to keep the battery load quite low if
possible."

I don't really know the asnwer to you exact question, except to say that the
idea of an external amplifier is to increase the volume beyond that of the
HU amp, so obviously it will draw more power. But as to which would draw
more power at the same volume, I'm not sure. The more watts the amp
produces the more power it will draw, assuming you turn the volume control
up!

I agree with Jupiter7 in that applying sound deadening material might help,
but I can't imagine it will help much with a small 4" speaker.

Tony





What's more likely? That an all-powerful mysterious god created the
universe and then decided not to give any proof of his existence? Or, that
he simply doesn't exist at all? And that we created him so that we wouldn't
have to feel so small and alone. -Eleanor Arroway, Contact