"Joseph Oberlander" wrote in message
link.net
Arny Krueger wrote:

Not quite. Harman owns both JBL & Infinity (and a ton of other
brands).. Infinity and JBL car audio speaker drivers may or may not
be made in the same Harman plant, no matter how the system is
branded. Ditto for Levinson.

Ah - my bad. But they are all very similar. The Infinity car
speakers are the premium brand, though - much better IME than the JBL
models.

They come out of the same factories and are made to spec per the
auto-company's engineering department. This means that if the auto-company
engineer who is in charge of the JBL-branded system is more skillful and
demanding than some other auto-company engineer who is in charge of a
Levinson or Infinity-branded system, he gets the better drivers, and the
better sound.


There is also a "voicing" step where parametric equalizers in the
electronics packages are tuned by auto-company engineers. This can have a
rather profound effect on the sound quality of the automotive system.

This contrasts with Bose systems which are almost entirely under the control
of Bose. If it is Bose-branded, all relevant sound quality choices have been
made by Bose staff. In the OEM car sound business, there is Bose and there
is everybody else. Everybody else sells pieces. Bose sells systems as they
are installed.

The standard final measures of OEM audio system sound quality are the E.H.
Power's customer satisfaction reports which are provided to the car
companies, for a price of course. They are highly distilled - just tables of
numbers, but they make very interesting reading. They show who is having
problems with catalytic converters or car radios. In some car companies
engineering-department staff and management professional progress are
largely pegged to Powers' reports. The results would surprise many.

They certainly sound better than the Alpine and Kenwoods from what
I have heard - but usually are too pricey for my budget - so I
usually "settle" for the Kenwoods - which sound 80% as good.

Under the covers, the electronics may well be made by Alpine. AFAIK Kenwood
is not pursuing OEM business.

It *might* be that the goofballs at the factory put a normal
factory stereo that is meant to drive 8 or 10 ohm stock
speakers in with a set of 4 or 6 ohm Infinitys.

Highly unlikely. OEM drivers are almost always 4 ohms or below because
switching power supplies are for all intents and purposes, no-nos.

A gross impedance
mismatch would create exactly the problem you are experiencing -
flabby, dull sound no matter what you do.

Highly unlikely. The major sources of bad car sound are car company
engineers who don't know, don't care, or are too deep into OEM-provided
perks to make discerning choices and demand the best.

I had a GM years ago
that had that problem - so I had to search a junkyard for stock
10 ohm 6*9s for the rear.($20 IIRC)

That would be years ago. At one time car radios (even SS car radios) had
output transformers.

You see - they put in the stereo first sometimes and sometimes
the speakers first - then slap the other unit in, so if you get
a "upgrade" package, sometimes they weren't really tested/mated
to work well together.

That was then, this is now.

I bet that a new stereo capable of driving all of the speakers at 4 ohms
will fix everything.

The quality of the speakers and their integration into the final package is
highly relevant. The audio electronics packages receive digital signals from
the vehicle body electronics that tell them how to configure themselves for
the particular vehicle's equipment, including the speakers.