From: jreiser@scott.skidmore.edu (jason reiser)
Subject: Re: Stereo Info.
Organization: Skidmore College, Saratoga Springs NY
Date: Mon, 28 Sep 1992 04:01:29 GMT

jcg2@ns1.cc.lehigh.edu (JASON GIRARD) writes:
> 
>     I'm a freshman at Lehigh and I've been into car audio for almost a year
>     now.  My past (and first) system consisted of a Pioneer GM-H100 amp
>     bridged to two Pioneer 10-in. subs in parallel in a homeade enclosure
>     built to spec.; a crutchfield 4x50P amp to two peerless midbass and two
>     Pyle 5-in. mids, and a Jensen A-80 amp to two Targa TW-3 tweeters.  I had
>     a Toshiba deck running to a Yamaha 400YGE EQ w/built-in 3-way crossover
>     (sub at 80 hz).

Are those 4 ohm or 8 ohm subs?  If they are 4 ohm you've got a
problem.  The GM-H100 amp will provide 100 watts mono into 8 ohms, or
160 watts into 4 ohms (per manufacturer's spec.).  Running the amp
mono into 2 ohms is not is a really bad idea with this amp. 

>     This coming summer, when I get back home from college, I plan to upgrade
>     my system.  In my first system, I had everything running off one battery,
>     and I could see the lights dim when the bass hit.  I'm goint to need an
>     alternate battery, but I don't know how to hook up a second battery.
>     Also, what role does an alternator play in the system?  Will I have to
>     upgrade it, and if so, how?  Any info. or suggestions would be extremely
>     helpful to me.

The dimming lights are a direct cause of the amps requiring extra
power when producing bass notes.  If you use 2 batteries, they will be
isolated with either relays, or a battery isolator.  (Check with a
reputible dealer).  Basically, this allows the system to run off of
one battery and the car from the other.  However, such a set-up is
often more of a band-aid than a real solution to the problem.  If you
are drawing more current than the alternator can produce, the battery
will be in a constant state of discharge (perhaps only partially).  If
you drive your car and listen to the radio at all times, and usually
at high volume, the audio system's battery will not have a chance to
charge as the power is all being used for music.  But if you often
drive without the radio, or with it at more reasonable level, this
might be a solution to the low current problem.

>     Lastly, I had my sub enclosure resting on the backseat.  I noticed that
>     the bass inside the car was intense, but outside it wasn't very
>     impressive.  Could this be due to the fact that the enclosure wasn't
>     secured to a solid place?

I highly doubt that the securing of the sub box will make any
considerable difference.  The box would have to move back by some
relevant distance (as compared with the wavelength of the note) to
make a difference in the sound... (and I believe it would have to do
that on every not... not possible).  At 55hz the wave is about 20 feet
long.  As far as the music being impressive only inside the vehicle, I
applaud you.  Do you really want to play music for the neighborhood?
Ask them if they want you to... and if they do, get them to chip in on
the new system.  To make the vehicle play loud enough for the
neighbors to complain takes power and a box that is optimized to play
higher bass notes.  If you built your box to spec, you might as well
just throw it away right now.  ;-)  Come on, you paid for it for
yourself, not for your buddies to flip quarters on the roof.  (The
same thing for people whose friends complain that the system sounds
bad when sitting in the back seat.  I would gladly design a system
that sounded good in the front and back, if my passengers would just
chip in the difference.)

>         Any suggestions anyone could provide about any part of my system would
>     be greatly appreciated (I am on a budget, you know).
>         If anyone wants to write, please do:
>                   Jason Girard
>                   BOX 489
>                   Lehigh University
>                   29 Trembley Drive
>                   Bethlehem PA 18015-3041
>         Thanx a million and keep on boomin'!
>                                       -Jason
> 
>                  
Jason, I am not really sure what you want to know.  Pounding systems
can be accomplished in a number of ways.  What kind of car do you have
and specifically, what is the problem with the system you have?  Let
us know, OK?

Oh great, now I guess I'll have to design a .sig (2 Jason's)

				- Jason 
jreiser@scott.skidmore.edu