> ...Certain comments proved especially
> useful, including the post from Frank (fmwong), who pointed out that "the
> factory head [unit] does not have RCA plugs which means you'd have to hook
> up the amp through line level converters. This has the potential of
> creating or picking up engine noise." My installer responded to this
> concern be saying that this depends on the quality of the line level
> converters used. He insists that if good quality ones are used, this
> should not be a problem.

> With the output levels of the BMW radios, a line output
converter is almost always unnecessary. We have three in our parking lot without them and without noise too, and I've personally done at least a half dozen more for friends. Simply choose an amp with a reasonably wide input sensitivity range. Connect the positive speaker output to the center conductor of an RCA jack. Connect the RCA jack shield connector to the head unit chassis NOT to the negative speaker wire. You can do this right at the radio or you can even do it at the amplifier end of the factory BMW harness for models which had the separate amp. Then set the amplifier input sensitivity so that the aftermarket amplifier reaches full output when the BMW radio volume control is pointing to the three O'clock position.

> Frank and Cary McReynolds both expressed concern that the MB Quart speakers
> can have a bright sound to the point of being annoying. My installer
> agreed that this can be true if they are underpowered. However, if they
> receive adequate power, the sound should continue to sound good in the car,
> as well as in the showroom.

Do a lot of listening before you buy. The frequency response of a speaker system is not going to change with power, only it's dynamic range. This is not going to change their "brightness", only the amount of distortion you hear at louder levels or on musical peaks. Maybe this is what your installer is hearing. Try to get the dealer to let you hear the speakers they recommend in a car. If they really feel that they are good speakers, somebody that works there probably has them in their car. The speaker choice is probably the most significant in your overall satisfaction with the system, so don't rush it and use your own ears, not just a recommendation.

Best Regards,
Bob Hazelwood
VP Product Management - a/d/s/

From digest.v4.n785 Fri Jun 28 18:48:11 1996 From: Bob Hazelwood <woodyh_at_ix.netcom.com> Date: Fri, 28 Jun 1996 21:25:47 -0400
Subject: Re: A "sound" decision

"Richard D. Birkenstock" <Richard_D_Birkenstock_at_cstar.ac.com> wrote: ... I've picked up on a couple of side

> comments from folks talking about the latest awesome thing they did their
> car's sound system. ...give folks some food for thought about that money
> being spent or in my opinion wasted on high end electronics...
>
> Ask any acoustic engineer and they'll most probably agree that a car is
> practically the WORST place to listen to music ...
I will admit that car manufacturers are making great

> strides to purposely think about speaker placement and sound but no amount of
> premium electronics and engineering will ever surmount all of these factors.
Cars are meant to be driven - especially your BMW!

> Turn the damn stereo off from time to time, roll the windows down and listen
> to your car...Spend the extra cash on your home system or a different
> accessory for your car instead. The standard BMW hi-fi system on any new
> model is plenty adequate in terms of quality and power - take the stock M3
> for example, 10 speakers, 250 Watts of Pioneer/Alpine engineering.

Hi Rich,
As a recent list subscriber I have done more reading than posting so far but your post happened to strike a sensitive chord with me so I've got to respond! The fact that I am in the business of designing car audio equipment certainly will help explain my differing opinion from yours. I would begin with friendly disagreement with your first point - the car is a great place to listen to music! It's a private, intimate space with fixed and controllable acoustics which are predictable and easily compensated for. In addition, the average person spends a significant portion of time commuting solo in less than sporting traffic conditions. I personally find the time and money spent on the sound system infinitely more valuable to me than similar investment in suspension and power improvements when I am averaging 15MPH on the Long Island Expressway at rush hour. On a nice twisty road in good weather and light traffic - yeah, turn off the stereo, roll down the windows and enjoy the car. Unfortunately I seem have about 14 of the former trips for every one of the latter, which sometimes makes me wonder why I even bothered with the performance stuff. You suggest spending the extra money on your home stereo. Unfortunately everytime I try to listen at home, my wife complains, the baby cries, the phone rings, or something else spoils the mood. It would seem that I am not alone here. In the course of my work, I have been involved with a number of consumer focus groups in order to understand our customers needs and behaviour. It was consistently revealed that home audio listening has primarily become a background music or home theater activity. Statistically the majority of people do their most serious music listening in the car! This is why the car manufacturers have finally begun to offer systems which are not as woefully incompetent as they once were. This is also why the car audio aftermarket continues to thrive even after the critics said that the improvement in OEM systems would kill it. Properly done, a good car audio system can add significantly to the total ownership experience. It doesn't have to be unreasonably complex and expensive, but logical high quality upgrades can make even mediocre systems, like the ones BMW offers, sound musical. I'm not referring to the excesses practiced by the "Death by Decibels" crowd, who would not think twice about adding 500 pounds of subwoofer enclosure to the trunk of an M3. Nor am I a fan of the all highs and all lows rapmaster school of system design, but the speakers and amplification of even the high-end BMW OEM systems are pretty limited in their fidelity. The BMW systems tend to have "screechy" highs and bass with no real power, definition or clarity. Even the midrange, which is actually pretty simple to get right, lacks warmth and is dynamically compressed. Sensible upgrades here can provide real improvement without getting into significant vehicle alterations and excessive expense. The radios and CD players on the other hand perform in many cases as well as one you would get in the aftermarket so it doesn't make a lot of sense to change them. If you are happy with the M3 system then put your money elsewhere, we all know there are plenty of good places to spend money on your Bimmer! But before you miss out on an opportunity to enjoy your M3 even more check out the factory system in a 1991 or 1992 Range Rover County SE (they went downhill after '94) or a Lexus GS300 and see if you're still happy with BMW audio.

Happy driving!

Bob Hazelwood
V.P. Product Management, a/d/s/

'87 325 (229kMi, original clutch! Nakamichi, a/d/s/, JBL, Audio Control. Racing Dynamics, Veloz, Momo) '96 M3 on the way