From: mm on
On Tue, 20 Apr 2010 11:24:55 -0500, OldSch00lf00l
<OldSch00lf00l(a)somewhere.com> wrote:

>mm wrote:
>> Please reply to this second post, or add alt.autos.gm to any reply to
>> the first post. I think GM folk would appreciate this thread, and
>> could contribute to it. I should have included them in the first
>> (identical) post.
>>
>>
>> GM car speakers in the 70's and maybe later versus other designs
>>
>> Chryslers and maybe many other makes have the two left speakers
>> connected to the left channel of the radio. GM radios OTOH used to
>> connect the front left and rear right speakers to the left channel,
>> and the others to the right.
>>
>> Or course, one can rewire his car either way, in most cases just by
>> interchanging two pairs of wires.
>>
>> Can you all tell me more about
>> GM's use of the LF-RR/RF-LR method of wiring speakers,
>> what this is called if I want to search the web for it, and
>> more about its use by GM and possibly other places?
>>
>> Also, in the opinion of the readers here, which method has more
>> advantages?
>>
>> Which is better for someone who is usually in the car alone?
>>
>> With GM I guess if you're in the back seat, the violins aren't on the
>> left anymore, but otoh, the volume for both channels should be the
>> same wherever one sit. No one sits in the center of a 4-seate car,
>> on the console or half-way between the front seat and back seat, so
>> the Chrysler system, used by most cars maybe, has a disadvantage that
>> if you have someone in the passenger seat, he hears more of the right
>> channel and you hear more of the left.
>>
>> GM's design solves most or all of that, although it lowers stereo
>> separation. And it depends on how often the driver will be alone and
>> how often there will be 1, 2, 3 passengers AND he'll be playing the
>> radio.
>>
>> OT3H, with Chrysler's design, if you are driving and others are
>> sleeping, you can move all the sound to the left front and leave the
>> other speakers very quiet, so they can sleep. Or if you're the
>> passenger and the driver doesn't like the station you want (though in
>> my world the driver gets to pick the station) you can turn everything
>> to the right front.
>
>The only thing I would have to add to this is to ask a question: What
>kind of reproduction was there in the 12 volt realm in the 70s? Stereo?
> I think not. I believe most vehicles had AM radios with 8 track decks
>and everything was MONO.

The past was longer ago than you imagine. By the time they built my
'72 or '73 Buick, stereio radios, maybe with cassette, were standard
in most makes of car (maybe not Volkswagon for example), although on
very cheap cars not made to order maybe only AM-FM monaural. I don't
know haw many years they had been

By the time they built my 67 Pontiac AM-FM was standard, although with
very cheap cars, only AM was included on the ones not made to order.
(OTOH the Cadillac had 5 buttons each of which did AM or FM stations
depending on whether one was listening to AM or FM, but I think mine
had 5 buttons that gave only one physical setting each.)

The '67 Pontiac had a reverberator too, with a dash mounted switch to
turn it off when people on the radio were talking instead of playing
music. And I was able to get a after-market stereo reverb amp for the
73 Buick.

My '50 Olds had an AM radio with 5 presets and it gave better sound
than did the factory radio in the '65 Pontiac that I got next. I had
a spare 1950 radio, which I installed in the 65 (Pushing it in between
the dash board and the transmission hump**) so I was able to compare
the soundss in the same car. It was a 6 volt tube radio but the 12
volts or the car were easily reduced to 6 with a resistor designed for
that purpose. The resistor did get hot, but I tucked it out of the
way.

**There were no consoles then because the seats held three people and
there was plenty of room on the dashboard for controls.


If the cars didn't have stereo, I couldn't have noticed the switched
Left and Right in the rear speakers.
From: GregS on
In article <4BCDD557.9060101(a)somewhere.com>, OldSch00lf00l <OldSch00lf00l(a)somewhere.com> wrote:
>mm wrote:
>> Please reply to this second post, or add alt.autos.gm to any reply to
>> the first post. I think GM folk would appreciate this thread, and
>> could contribute to it. I should have included them in the first
>> (identical) post.
>>
>>
>> GM car speakers in the 70's and maybe later versus other designs
>>
>> Chryslers and maybe many other makes have the two left speakers
>> connected to the left channel of the radio. GM radios OTOH used to
>> connect the front left and rear right speakers to the left channel,
>> and the others to the right.
>>
>> Or course, one can rewire his car either way, in most cases just by
>> interchanging two pairs of wires.
>>
>> Can you all tell me more about
>> GM's use of the LF-RR/RF-LR method of wiring speakers,
>> what this is called if I want to search the web for it, and
>> more about its use by GM and possibly other places?
>>
>> Also, in the opinion of the readers here, which method has more
>> advantages?
>>
>> Which is better for someone who is usually in the car alone?
>>
>> With GM I guess if you're in the back seat, the violins aren't on the
>> left anymore, but otoh, the volume for both channels should be the
>> same wherever one sit. No one sits in the center of a 4-seate car,
>> on the console or half-way between the front seat and back seat, so
>> the Chrysler system, used by most cars maybe, has a disadvantage that
>> if you have someone in the passenger seat, he hears more of the right
>> channel and you hear more of the left.
>>
>> GM's design solves most or all of that, although it lowers stereo
>> separation. And it depends on how often the driver will be alone and
>> how often there will be 1, 2, 3 passengers AND he'll be playing the
>> radio.
>>
>> OT3H, with Chrysler's design, if you are driving and others are
>> sleeping, you can move all the sound to the left front and leave the
>> other speakers very quiet, so they can sleep. Or if you're the
>> passenger and the driver doesn't like the station you want (though in
>> my world the driver gets to pick the station) you can turn everything
>> to the right front.
>
>The only thing I would have to add to this is to ask a question: What
>kind of reproduction was there in the 12 volt realm in the 70s? Stereo?
> I think not. I believe most vehicles had AM radios with 8 track decks
>and everything was MONO.

I did use Am for most of the 70's partly because for a couple years
there was no FM where I lived. There was not much on the FM dial
at the beginning of 1970, but it quickly changed.
I used 8 track STEREO through most of the 70's.
I also recorded 8 track stereo, and most of my music was self recorded
from albums and later FM. We had an FM station that played whole albums.
From 1972 to 1977, I had 4 channel matrix quad in my Mustang.
I did not go high power until 1978. 36 watts per channel, Craig. Also switched to Cassette.

I really hate the volume controls on OEM. They are weird.
I also need at least 10 push buttons on the front panel for station selection.
Menues suck.

greg




From: OldSch00lf00l on
mm wrote:
> Please reply to this second post, or add alt.autos.gm to any reply to
> the first post. I think GM folk would appreciate this thread, and
> could contribute to it. I should have included them in the first
> (identical) post.
>
>
> GM car speakers in the 70's and maybe later versus other designs
>
> Chryslers and maybe many other makes have the two left speakers
> connected to the left channel of the radio. GM radios OTOH used to
> connect the front left and rear right speakers to the left channel,
> and the others to the right.
>
> Or course, one can rewire his car either way, in most cases just by
> interchanging two pairs of wires.
>
> Can you all tell me more about
> GM's use of the LF-RR/RF-LR method of wiring speakers,
> what this is called if I want to search the web for it, and
> more about its use by GM and possibly other places?
>
> Also, in the opinion of the readers here, which method has more
> advantages?
>
> Which is better for someone who is usually in the car alone?
>
> With GM I guess if you're in the back seat, the violins aren't on the
> left anymore, but otoh, the volume for both channels should be the
> same wherever one sit. No one sits in the center of a 4-seate car,
> on the console or half-way between the front seat and back seat, so
> the Chrysler system, used by most cars maybe, has a disadvantage that
> if you have someone in the passenger seat, he hears more of the right
> channel and you hear more of the left.
>
> GM's design solves most or all of that, although it lowers stereo
> separation. And it depends on how often the driver will be alone and
> how often there will be 1, 2, 3 passengers AND he'll be playing the
> radio.
>
> OT3H, with Chrysler's design, if you are driving and others are
> sleeping, you can move all the sound to the left front and leave the
> other speakers very quiet, so they can sleep. Or if you're the
> passenger and the driver doesn't like the station you want (though in
> my world the driver gets to pick the station) you can turn everything
> to the right front.

The only thing I would have to add to this is to ask a question: What
kind of reproduction was there in the 12 volt realm in the 70s? Stereo?
I think not. I believe most vehicles had AM radios with 8 track decks
and everything was MONO.