HDTenEightyP/NetNews huggingface dataset:
From: al1x+@andrew.cmu.edu (Amit Likhyani)
Newsgroups: rec.audio.car
Subject: Re: are alternators too weak for amps?
Date: 13 Dec 92 18:03:34 GMT
Organization: Senior, Electrical and Computer Engineering, Carnegie Mellon, Pittsburgh, PA

I just got a 140 amp delco alternator installed in my car.  This is what
happens:

Your alternator is rated for a certain amperage in my case it was 65 amps.
At idle, it does not put out as much as when you are accelerating.  Mine
could put out 85 amps when accelerating, but more like 50 at idle.  

Your car will draw a certain amount of current depending on what
accessories are on.  In my case, the headlights would dim at
intersections when the car was no longer accelerating, but rather
idling.  With the air conditioner and fan on, sometimes my head unit
would not get enough juice to stay on.
What happens is that your stereo is putting the total current draw above what
your alternator can put out at idle.  I am sure that when you are
accelerating, the problem goes away.  The problem is that when you draw
current off your amp, the battery picks up whatever slack the alternator
cannot handle so even while driving, your battery is getting drained. 
This is murder on a battery.  We watched my stereo at idle and I was
getting negative 10 to 14 amps on bass notes.  I am getting an Orion
225HCCA to go along with my PPI 4100AM, so I had no prayer of using my
wussie alternator.
The term High Current Capable Amp(or whatever HCCA stands for) scared me away.

After one day, I have noticed that my battery is a hell of a lot
stronger now that my alternator is keeping up with the demands of my
amps.  The car is starting with ease, the headlights are not dimming,
and I can tell that there is a lot more power in the system.  The dash
lights are brighter and the 
head unit lights do not dim with bass notes.

My symptoms use to be that the headlights dimmed with the bass.  When my
power locks actuated, you could see my head unit lights dim along with
the stalling of my stereo at intersections.

If you don't want to get a new alternator, you can try to jack the idle
speed up.  That will put out more juice at idle.  I don't know if it
hurts fuel economy or not.  I am going to jack mine up when I figure out
how to do it(damn Japanese cars).  Right now, I am putting out 70 amps
at idle.  The guy temporary turned the idle screw and we had it up to
110 amps at idle which is probably higher than I needed or wanted, but
he could not set the screw.  If anyone has any info on how to jack the
idle up on a 1988 Mitsubishi Mirage, please drop me a line.  The car has
a carbeurator.  We took it off, but could not figure out what was going
on underneath.

Before getting a new alternator, make sure your power wire is thick
enough, but that does not sound like it would effect your headlights.

Some people are lucky in that their car has a built in margin of current
that their alternator can handle, so a moderate stereo system is not a
problem.
Newsgroups: rec.audio.car
From: eddys@citrus.SAC.CA.US ( Steve Eddy )
Subject: Re: CLASS A AMP INFO
Organization: Citrus Grove Public Access ( 916 ) 381-5822    Sacramento CA.  USA
Date: Fri, 18 Dec 1992 01:10:55 GMT
X-Newsreader: Tin 1.1 PL4

maley@nmt.edu (Mark Maley) writes:

: Despite all this, one question remains.  Why are home amps of Class A
: design found to be the absolute most expensive, and yet an auto amp
: of similar class in this case is found to be a measly $100?  
: 
: Mark
: 
: maley@jupiter.nmt.edu
: 
: p.s. I beg of the original poster to please give us more specs and info.  
:      Perhaps a distortion rating?
: 
: 

   A number of reasons, actually. First, I doubt very seriously that the
Bolt amplifer in question is truly a class-A amplifier. Perhaps all that's
class-A about it is the input circuitry (which requires nothing special).
Secondly, class-A home amplifiers are usually of the "cost not object"
variety, encompassing not just better parts and components, but such things
as chassis and other hardware. The only really discernable "performance
difference" between a class-A/B amplifier and a less efficient class-A
amplifier will show up on your power bill, not in the listening room. Simply
put, class-A home amplifiers are just built better and that adds to the
cost. Not really any different than cars. A Toyota will get you to the
nearest 7-Eleven just the same as a Rolls Royce. But the Rolls is "built"
better and has a higher price tag. 

   One advantage that car amplifiers have over home amplifiers at least in
terms of price, is that car amplifiers run off of much more efficient
"switching" power supplies which operate at frequencies upwards of 50kHz and
more, whereas with the 60Hz AC which our homes are wired with, it requires
VERY large (relatively speaking) power transformers. A high-quality, 1kVA
toroid power transformer for a home power amplifier might cost upwards of
$120 (wholesale). If you apply the industry standard "retail price = 5 times
the cost or parts" rule of thumb, a power transformer alone could make up
$600 of the final retail price of the amplifier. Hope this helps answer some
of your questions.

se

-- 

# Where no man has gone before.                   eddys@citrus.SAC.CA.US
#   *default* .sig file                      csusac.ecs.csus.edu!citrus!eddys
# The undiscovered land.                                   /\../\
From: cjm9321@hertz.njit.edu (The InfoMan)
Newsgroups: rec.audio.car
Subject: Re: How many remote leads?
Date: 16 Dec 92 18:49:46 GMT
Distribution: na
Organization: New Jersey Institute of Technology, Newark, N.J.

In article <17565@umd5.umd.edu> ui68@linus.umd.edu (Bill Kyte) writes:
>
>   I have a small question for the net.  How many leads can you run off of 
>the head units remote wire? I want to run two or three amps and don't know
>what to do with the other two remote leads from the amps.
>Anyone's help would be greatly appreciated.
>       Thank you
>                  -Bill

	Crutchfied has something about this in one of there free
literature booklettes. They say to use a relay (I forgot which one)
connected to the remote of the head unit so that it switches to a fused
wire connected to the battery. Then the output from the relay would be
coming directly from the battery so you can connect that wire to a
distribution block.

					Hope that helps,

-- 
M A D E   .   . .---. .---.    \  Buy U.S.A. products,  /    xxxxx ==========
  I N     |   |  \    |___|    <     It's YOUR job.     >    xxxxx ========== 
 T H E    |   |    \  |   |    <  Christopher J. Massa  >    ================
-------   `---' `---' '   `    / cjm9321@hertz.njit.edu \    ================
From: darren@citron.ucsb.edu (Darren Tokushige)
Newsgroups: rec.audio.car
Subject: Legacy Loudspeaker Specs...
Date: 14 Dec 92 12:03:36 GMT
Organization: University of California, Santa Barbara


I am posting this message on behalf of Paul Port...

     Hello,
	 I'm trying to find someone who knows
anything about LEGACY in-car-entertainment gear. I believe they are made in the
USA, and we have only one UK importer ( who is completely useless ! ). I'm
after the enclosure peramaters for their 18'' sub ( LW1870P ), the peramaters
given to me by Sterling ICE ( the importer ) when run through perfect box give
a recomended enclosure size about half the size of the car (Peugeot 309).
Compare that with the size of enclosure Legacy make for the driver which you
can almost pick up with one hand !
  It is very possible that the info. I have is incorrect - as it is actually for
another manufacturers driver ( sterling said that they were basically the same
though !!!). Could you please therefore forward this letter to any appropriate
buletin boards over there in the hope someone may know something.

    Thankyou.

                 Yours Faithfully 
                                      Paul Port

    E.Mail :-       P.S.Port@uk.ac.hull.seq




			Darren Tokushige
		      (darren@cs.ucsb.edu)
Newsgroups: rec.audio.car
From: cces@ecf.toronto.edu (Congress of Can Eng Students)
Subject: Re: Class A MOSFET Power Amp for sale...
Organization: University of Toronto, Engineering Computing Facility
Distribution: na
Date: Fri, 11 Dec 1992 20:38:15 GMT

In article <1992Dec11.001832.13833@henson.cc.wwu.edu> n8842401@henson.cc.wwu.edu (Matthew Stearns) writes:
>veloovet writes:
>
>>    I have a Bolt MOSFET car power amp for sale
>>    Here are some of the specifications:
>>        Class A...
>>        Full MOSFET power supply...
>
>You of course realize that "class A" refers to a type of 
>power supply, and "MOSFET" refers to another type of 
>power supply.  No one amp can be both!  
>
>...Just thought I'd point this out...

Actually, the Class A specification is an indication of the amplifier output
stage type.  And (even though I am not too sure of the terminology that is
used in amp specs) the MOSFET designation would indicate that the output
stage is implemented using MOSFET transistors.

Wadda ya think? 

-- 
 ________________________ __________________________ _________________________
/ Brian Campanotti       |                          |"You can shift            \
| Electrical Engineering | cces@ecf.utoronto.ca     | perception...but reality |
| University of Toronto  | campano@ecf.utoronto.ca  | won't change..."         |
From: hhtra@usho72.hou281.chevron.com (T.M.Haddock)
Newsgroups: rec.audio.car
Subject: Imaging Problem?
Date: 14 Dec 92 23:28:12 GMT
Organization: Chevron


 Okay, I've had my new system for about a month now and it's real nice.
 I have components in the front doors with coaxials and small subs in 
 the rear doors, bi-amped, and all crossed actively.
 But I have noticed a small problem - IMAGING.

 Alpine Australia has a new test CD that has a track for testing imaging
 with a voice that moves from LEFT CHANNEL to LEFT CENTRE (Aussie spelling)
 to CENTRE to RIGHT CENTRE to RIGHT CHANNEL.

 When I sit in the driver's seat, I hear:

   LEFT CHANNEL  - voice is low to the left on the driver's side window
   LEFT CENTRE   - voice is higher, about middle of the left roof pillar.
   CENTRE        - voice seems to be coming from everywhere, not just 
                   from the center of the windshield  -  problem area?
   RIGHT CENTRE  - voice is about middle of the right roof pillar.
   RIGHT CHANNEL - voice is low to the right on the passenger's side window.

 If I sit in the middle of the front seat, the CENTRE voice seems to come
 from the entire windshield, not a tight localized spot like the other 
 voice positions.  The best image is from the middle of the back seat.
 There the voice moves from extreme left to right like it should with a
 tighter but still slightly broad centre.  The image also has alot more
 DEPTH to it from the rear seat.

 Is this broad, omni-directional centre voice something that can be
 corrected by a center-channel speaker and/or image processor like the
 Audio Control ESP-2 or ESP-3?  If so, what size speaker should it be?
 What brand?  type?  freq range?  power?  I have a small space in my dash
 that might take something as large as a 4"x6" plate.  Are there any 
 other image processors that support center channel?

 Or should I try playing with my Audio Control 4XS some more?  If so,
 what should I try?

 Or anything other advice, something I may have missed?


 Thanks in advance.

 TRAVIS
 hhtra@hou281.chevron.com
From: kirk@hpcc01.corp.hp.com (Kirk Lindstrom)
Date: Fri, 11 Dec 1992 00:31:01 GMT
Subject: Re: Books, FAQ's etc
Organization: Shredding the water of SF Bay, HP-OCD
Newsgroups: rec.audio.car

#######                           ###     ###     ###
#     #   ####   #####    ####    ###     ###     ###
#     #  #    #  #    #  #        ###     ###     ###
#     #  #    #  #    #   ####     #       #       #
#     #  #    #  #####        #
#     #  #    #  #       #    #   ###     ###     ###
#######   ####   #        ####    ###     ###     ###

When I goof, I do it big time!
>>
>Need to know the efficiency of the speakers and how much power is being
>delivered.  Double the power to a given speaker and it just "gets a bit
>louder" so having lots of power is good as it is more likely to be clean.
>
>>3. Sensitivity is quoted as Db @ 1 watt @ 1 metre, what does the
>>   figure tell you?
>>
Error is here:
>Relative loudness between speakers.  roughly speaking, a 91 dbW/m SPL speaker
>running at 10 watts will be just as loud as an 88 dbW/m SPL speaker running
>at 100 watts.
>
>Kirk out
>----------

That should be :
Relative loudness between speakers.  Roughly speaking, a 91 dbW/m SPL speaker
running at 50 watts will be just as loud as an 88 dbW/m SPL speaker running
at 100 watts.

Why?  Power doubling is Delta db = 10*log(P1/P2) = 10*log(2) = 3 db

Hope I caught this before the flames melt my voice-coil!

Kirk out
Newsgroups: rec.audio.car
From: RYNA10@waccvm.corp.mot.com (Jay Kopycinski)
Subject: CLASS A AMP INFO
Organization: Motorola
Date: 15 Dec 1992 08:23:40 MST

------------------------- Original Article -------------------------
From: maley@nmt.edu (Mark Maley)
Newsgroups: rec.audio.car
Subject: Re: Class A MOSFET Power Amp for sale...
Date: 13 Dec 92 18:35:39 GMT
Organization: New Mexico Tech

In article <Bz56Ax.IGJ@citrus.SAC.CA.US> eddys@citrus.SAC.CA.US ( Steve Eddy ) w
>n8842401@henson.cc.wwu.edu (Matthew Stearns) writes:
>: veloovet writes:
>:
>: >    I have a Bolt MOSFET car power amp for sale
>: >    Here are some of the specifications:
>: >        Class A...
>: >        Full MOSFET power supply...
>:
>:
>: ...Just thought I'd point this out...
>which is applied typically to amplifier output stages and has nothing to do
>with power supplies, and "MOSFET" refers to a type of transistor which can
>be used in power supplies OR amplifier output stages.
>
> ...Just thought I'd point this out...
>
>******** Theoretical efficiency of a class A amp is 50%.  Most car amps
>do not use 12 volts for the amp supply.  They use a switching power
supply (running at about 25-30 KHz) to "boost" the DC collector or
drain supply upwards.  (This converts the 12 volts to something higher.)
This then allows higher voltage swings and allows greater power output
to the load...........
From: philip@hpsgrt1.sgp.hp.com (Philip LOH)
Newsgroups: rec.audio.car
Subject: Re: Class A MOSFET Power Amp Forsale
Date: 15 Dec 92 00:58:20 GMT
Organization: APCD, Hewlett-Packard Singapore

/ hpsgrt1:rec.audio.car / veloovet@silver.ucs.indiana.edu (mohan veloo vethiveloo) /  3:39 am  Dec 11, 1992 /

 I need to sell this amp because i've bought a new one.
 
    I have a Bolt MOSFET car power amp for sale
    Here are some of the specifications:
        Class A
        25w/ch x 4 into 4ohms
        50w/ch x 4 into 2 ohms
        Full MOSFET power supply
        Discrete components
        2 ohm stable
        gold plated leads


 I'm asking $100 obo. Make an offer and I'll consider it.

 You can contact me at (812) 333-2430 or email me at VELOOVET@ucs.indiana.edu.



----------
Newsgroups: rec.audio.car
From: eddys@citrus.SAC.CA.US ( Steve Eddy )
Subject: Re: Class A MOSFET Power Amp for sale...
Organization: Citrus Grove Public Access ( 916 ) 381-5822    Sacramento CA.  USA
Date: Sat, 12 Dec 1992 10:25:45 GMT
X-Newsreader: Tin 1.1 PL4

n8842401@henson.cc.wwu.edu (Matthew Stearns) writes:
: veloovet writes:
: 
: >    I have a Bolt MOSFET car power amp for sale
: >    Here are some of the specifications:
: >        Class A...
: >        Full MOSFET power supply...
: 
: You of course realize that "class A" refers to a type of 
: power supply, and "MOSFET" refers to another type of 
: power supply.  No one amp can be both!  
: 
: ...Just thought I'd point this out...

   You of course realize that "class A" refers to a type of biasing scheme
which is applied typically to amplifier output stages and has nothing to do
with power supplies, and "MOSFET" refers to a type of transistor which can
be used in power supplies OR amplifier output stages. 
 
 ...Just thought I'd point this out...

se

-- 

# Where no man has gone before.                   eddys@citrus.SAC.CA.US
#   *default* .sig file                      csusac.ecs.csus.edu!citrus!eddys
# The undiscovered land.                                   /\../\
Newsgroups: rec.audio.car
From: eddys@citrus.SAC.CA.US ( Steve Eddy )
Subject: Re: Class A MOSFET Power Amp for sale...
Organization: Citrus Grove Public Access ( 916 ) 381-5822    Sacramento CA.  USA
Date: Fri, 18 Dec 1992 00:42:19 GMT
X-Newsreader: Tin 1.1 PL4

sward@vaxwrk.enet.dec.com (Peter Sward) writes:
: 	Most of the CLASS-A car amps out there are advertised as CLASS-A
: 	BUT are reall high biased AB amps. What the CLASS-A really means is
: 	that the input stage is running in class A but the power stage is
: 	running in a high AB.
: 
: 	Peter
: 
 
   That's what I have found as well. I've had a Soundstream Class A 100 on
the test becnch and (at least this particular sample) definitely wasn't
biased in true class-A. And as you say, most references to class-A where
amplifers are concerned is on the input stage. Have you (or anyone else out
there for that matter) come across any TRUE class-A car amplifiers? And I
mean verified, not just manufacturer's claims. I plan to release a class-A
amplifier sometime in the first quarter of '93 and so far my research has so
far turned up nothing. If there is a true class-A amplifier out there, I'd
like to know about it (see what the "competition" up to). Regards.
 
se
 

-- 

# Where no man has gone before.                   eddys@citrus.SAC.CA.US
#   *default* .sig file                      csusac.ecs.csus.edu!citrus!eddys
# The undiscovered land.                                   /\../\
From: f4ax@vax5.cit.cornell.edu
Newsgroups: rec.audio.car
Subject: Re: Can I run car stereo on battery charger?
Date: 17 Dec 92 11:28:06 EST
Distribution: rec
Organization: Cornell University

In article <1992Dec16.155512.45695@kuhub.cc.ukans.edu>,
thompson@kuhub.cc.ukans.edu writes: 
> Hello all,
> 
> I have a Clarion 9772RT pull out car stereo tape/receiver.  I also have
> a Kenwood 50x2 watt amp, and two Sony 6x9 speakers.  All of this equipment
> is sitting in my room doing nothing (I won't have a car for a while).
> 
> I had an idea about how to use this car stereo equipment with the house
> electricity (110 volt I guess).  Can I use a car battery trickle chargerer?
> I can get a 10 amp one for $30.  Am I right in assuming that a 10 amp
> charger charging at 12 volts (car voltage) will yield (10 * 12) 120 watts
> of power before overloading?  I thought I heard that amps * volts = watts.
> Is this true.  If it is, is this a safe way to run my car stereo on my
> house current?  I could use a surge protector to prevent spikes.  Is there
> anything that I should be warned about that might damage my equipment by
> doing this?  
> 
> I await any responses.  Thanks.
> 
> -- 
> | Charles A. Thompson      | thompson@ukanvm.cc.ukans.edu        |
> | University of Kansas     | thompson@ukanvax.cc.ukans.edu       |
> | > They call me SkiBum <  | 32 bit OS/2 2.0 is for you!         |
> |----------------------------------------------------------------|
> | Listen to Rush Limbaugh from 12-3 EST on the radio EVERYWHERE! |
> ------------------------------------------------------------------

Can't you just buy an AC to DC and reverse converter?  As I recall, they are
about $30-$50 and you can use any car appliance on it.
Newsgroups: rec.audio.car
From: RYNA10@waccvm.corp.mot.com (Jay Kopycinski)
Subject: CLASS A/MOSFET
Organization: Motorola
Date: 11 Dec 1992 08:38:40 MST

------------------------- Original Article -------------------------
From: n8842401@henson.cc.wwu.edu (Matthew Stearns)
Newsgroups: rec.audio.car
Subject: Re: Class A MOSFET Power Amp for sale...
Date: 11 Dec 92 00:18:32 GMT
Article-I.D.: henson.1992Dec11.001832.13833
Organization: Western Washington University

Xref: henson misc.forsale:56062 rec.audio.car:7528
From: veloovet@silver.ucs.indiana.edu (mohan veloo vethiveloo)
Newsgroups: misc.forsale,rec.audio.car
Subject: Class A MOSFET Power Amp Forsale
Keywords: forsale..
Date: 10 Dec 92 19:39:41 GMT
Article-I.D.: usenet.Bz26M6.7G1
Organization: Indiana University

veloovet writes:

>    I have a Bolt MOSFET car power amp for sale
>    Here are some of the specifications:
>        Class A...
>        Full MOSFET power supply...

You of course realize that "class A" refers to a type of
power supply, and "MOSFET" refers to another type of
power supply.  No one amp can be both!

...Just thought I'd point this out...


******** Not so....Class A refers to the bias point of the active devices
in the amp.  A class A amp has the operating point set such that
current in the output circuit flows at all times, and itoperates over
the linear portion of its characteristic curve.  MOSFET is simply one
type of active device, in this case a field effect transistor.
Hope this is helpful..........
Jay
From: Peter Hsrris <pharris@ucscm.ucsc.edu>
Newsgroups: rec.audio.car
Subject: 88 Mazda 929 & CD
Date: 15 Dec 1992 00:20:30 GMT
Organization: University of California, Santa Cruz
Distribution: world
NNTP-Posting-Host: twilight-mac13.ucsc.edu
X-UserAgent: Nuntius v1.1.1d13
X-XXMessage-ID: <A75265F42803025D@twilight-mac13.ucsc.edu>
X-XXDate: Mon, 14 Dec 92 01:25:24 GMT

I
929. It looks as if one would fit if I were to take out the ashtray. I
have been told that the receiver has an auxiliary input, and all I
would be a selector switch (and the CD player of course.) Any advice or
comments from cyberland??
From: kcchu@gandalf.rutgers.edu (Keith Chu)
Newsgroups: rec.audio
Subject: CD Plyr Service Contracts?
Keywords: Is it worth the Money?
Date: 15 Dec 92 21:35:44 GMT
Organization: Rutgers Univ., New Brunswick, N.J.



Hi everyone,

I just Purchased a Kenwood Multi disk CD player. model# ???6640.
I gave my Harmon Kardon HD300 to my mother.  I got the player
at an appliance/electronics store (TOPS) and as usual, the salesman
pushed the 5 year service contract for $50.00.  I usually don't get
service contracts since many of these stores can disappear in 5 years
and I haven't had any problems with any of my equipement. Portables,
T.V.'s etc. that I have ever bought that the regular service contract
won't cover.

The salesman did bring up a point that I can't figure out if it's just
a line or if it's true.   He told me that within 3-5 years the lasers
will have to be syncronized or realigned.  And that this is even more
of a problem with multi-disk players.  My Harmon Kardon is already 4
years old and I haven't had a problem with it at all.  

So my questions are:

Why would the lasers on a multi-disk player would get any more out of wack than
a single disk?  even if the laser assembly moves in a magazine CD
changer, the focus shouldn't be affected by the movement.

Do any of you normally get extended contracts for your equip. that is
20% of the purchase price?  He was quoting me $150 for the adjustment.

I know this guy was trying to get more money out of me, but was he right?
-- 
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