Speaker-Eating dashboard?

[JoeSpareBedroom]

It doesn't?!

(He don't know me too well...)

I have a JVC headunit in my Supra, powering a 100Wx4 channel amp, and 4
100W MB Quarts at each corner. Since the roof comes off the car, I wanted
something I could hear over the road and wind noise.

3rd year and no problem! I rarely have problems with my installations.
That's why this is so perplexing.

But, I am a bass player, so I want to HEAR the bass. It's just odd that
it's always this one speaker! The left front has been in there since I
took the original pair out. I always replace with 4 ohm speakers so the
balance is correct all the way around.

You're asking for something that's *just about* physically impossible from
5" speakers in imperfect enclosures (doors). Here's an experiment you might
want to try, though. I have been told that Radio Shack sells a decibel meter
that reasonably accurate. With the car's top off, and no Harley or 18
wheeler nearby to add noise, measure how many decibels of noise there are
just driving down the road with the radio off. I think you'll find that it's
pretty close to 100db, especially with the wind in certain directions
relative to the car.

To make enough clean, tight bass to overcome that noise if it existed in a
bar, you'd want a lot more power than you have. You'd have larger speakers,
and the enclosures would be designed for those speakers. I'm also a bass
player, so don't debate this, OK?

By the way, what's the brand and model of your car amp?

 

[Hachiroku $B%O%A%m%/(B]

To make enough clean, tight bass to overcome that noise if it existed in a
bar, you'd want a lot more power than you have. You'd have larger
speakers, and the enclosures would be designed for those speakers. I'm
also a bass player, so don't debate this, OK?

But...but...I get a MUCH better sound out of my Ampeg SVT 4-10" than I do
out of my 2-15" Fender! I just have the Fender 'cause it weighs 50 LBS
less!

By the way, what's the brand and model of your car amp?

Genuine Optimus! They were blowing them out when RadShack got out of the
car stereo business. I got it for $30 NIB...

Yeah, not the best. But it's not the Supra that's chewing the speakers,
it's the Mazda. The Supra sounds *GREAT*! (MB Quarts all around help, and
these ones DIDN'T separate from the frames!

 

[JoeSpareBedroom]

But...but...I get a MUCH better sound out of my Ampeg SVT 4-10" than I do
out of my 2-15" Fender! I just have the Fender 'cause it weighs 50 LBS
less!



Genuine Optimus! They were blowing them out when RadShack got out of the
car stereo business. I got it for $30 NIB...

Yeah, not the best. But it's not the Supra that's chewing the speakers,
it's the Mazda. The Supra sounds *GREAT*! (MB Quarts all around help, and
these ones DIDN'T separate from the frames!

OK. Save me from having to read back through the clutter again. In the
Mazda, what is powering the speakers? Brand & model of amp, please.

 

[Hachiroku $B%O%A%m%/(B]

OK. Save me from having to read back through the clutter again. In the
Mazda, what is powering the speakers? Brand & model of amp, please.

Just a plain old JVC head unit rated at 50W/channel (Effectively, 22W RMS)
Speakers rated for 50W


I can't remember when I changed the speakers, because before that I was
running an AIWA CD player. So, I should change the speakers and see if it
still happens.

Problem is, it did it with the original pair in the car with a Kenwood
Cassette deck. I changed the deck and the speakers at the same time, and
then changed the speakers twice more. I'm running out of low-end speakers,
and ain't putting a set of Quarts in there!

 

[JoeSpareBedroom]

Just a plain old JVC head unit rated at 50W/channel (Effectively, 22W RMS)
Speakers rated for 50W


I can't remember when I changed the speakers, because before that I was
running an AIWA CD player. So, I should change the speakers and see if it
still happens.

Problem is, it did it with the original pair in the car with a Kenwood
Cassette deck. I changed the deck and the speakers at the same time, and
then changed the speakers twice more. I'm running out of low-end speakers,
and ain't putting a set of Quarts in there!

There's your answer. Your Kenwood is frying the speakers. I don't care WHAT
the claimed wattage is, or how much power the speakers can handle. You don't
have enough power to run them safely.

 

[Hachiroku $B%O%A%m%/(B]

There's your answer. Your Kenwood is frying the speakers. I don't care
WHAT the claimed wattage is, or how much power the speakers can handle.
You don't have enough power to run them safely.

I pulled the Kenwood and installed the AIWA. THe left dash speaker was
buzzing off the bat. I replaced it with another set of known good
speakers, and the left dash speaker started buzzing after about 10-12
weeks. I replaced the speakers as a paor with new Clarions. After 10-12
weeks, the new Clarion left dash speaker started buzzing. I replaced the
AIWA with a JVC, and replaced the left dash speaker with another known
good speaker. This time it lasted about 3 weeks...

 

[Bruce L. Bergman]

I pulled the Kenwood and installed the AIWA. THe left dash speaker was
buzzing off the bat. I replaced it with another set of known good
speakers, and the left dash speaker started buzzing after about 10-12
weeks. I replaced the speakers as a paor with new Clarions. After 10-12
weeks, the new Clarion left dash speaker started buzzing. I replaced the
AIWA with a JVC, and replaced the left dash speaker with another known
good speaker. This time it lasted about 3 weeks...

Are you running through the factory speaker wiring from the radio to
the front speakers? There could be a power cross or a ground in the
harness, and sticking a DC bias on speakers will kill them pronto.

--<< Bruce >>--

 

[Hachiroku $B%O%A%m%/(B]

Are you running through the factory speaker wiring from the radio to
the front speakers? There could be a power cross or a ground in the
harness, and sticking a DC bias on speakers will kill them pronto.

--<< Bruce >>--

Yes, it is the factory wiring, but it appears to have no common grounding
(I thought that went out with Bell-Bottoms...)

Everything looks good. I also have a set of Infinity 6x9's in the rear
deck, and they are performing perfectly. It's just that one speaker in the
dash...

 

[JoeSpareBedroom]

Yes, it is the factory wiring, but it appears to have no common grounding
(I thought that went out with Bell-Bottoms...)

Everything looks good. I also have a set of Infinity 6x9's in the rear
deck, and they are performing perfectly. It's just that one speaker in the
dash...

The floating ground question is a good one. It would cost you what - eleven
cents and 20 minutes to run a pair of speaker wires?

Other points:

- You mentioned that one of the head units had 22 watts RMS per channel. For
4 speakers, two of which are probably eating lots of power (the rears) and
two of which are not in proper enclosers (dash speakers), that's a recipe
for disaster.

- Dash speakers never were a good idea. They still are not a good idea and
never will be a good idea. They are not truly enclosed, so they are not
damped by a mass of air behind them. There are ways to filter out bass only
to those speakers, which effectively makes them into tweeters. Some people
stick capacitors on the speakers, but I never did that and can't help with
details. We used to use crossovers followed by two amplifiers, using combos
like 50 per channel to the rears and 20 per channel to the fronts. Do you
understand that general concept?

- Here's a mantra for you to repeat, for as many days or months it takes to
believe it: There is no head unit with enough power for some car systems.
"System" is defined as the possible assortment of speakers in a given car
(without cutting new holes), combined with the listening habits of the
particular person. If it were possible to build decent power into a package
as small as a head unit, you'd see home stereos that small and light.

Start with new wiring, and then begin chanting the rest of the information
until you're ready to digest more information.

 

[Hachiroku $B%O%A%m%/(B]

We used to use crossovers followed by two amplifiers,
using combos like 50 per channel to the rears and 20 per channel to the
fronts. Do you understand that general concept?

COOL!!!

I did that with my Corolla GTS: ran a line to the rear of the car, and
then used an electronic crossover, and then ran the outputs from that to
separate amps; 60WPC for the bass, 40WPC for the mids and 30WPC for the
tweets.

The fronts I used just off the shelf RadShack X-overs split to the
speakers. I had 55WPC running the fronts.

It sounded SWEET!