On Wed, 15 Oct 2003 15:02:01 -0400, "Robert Morein"
wrote:


"Ron" wrote in message
.. .
On Wed, 15 Oct 2003 04:06:08 -0400, "Robert Morein"
wrote:


"Ron" wrote in message
news On Tue, 14 Oct 2003 20:47:00 -0400, "Robert Morein"
wrote:


"WindsorFox[SS]" wrote in message
news:Je0jb.73317$AH4.43019@lakeread06...
Nexxon wrote:
NEXXON_CAR_AUDIO - The Best for Less
Over 19,000+ Car Audio, 7,000+ Home Electronics Products, Free
Shipping Satisfaction Guaranteed, 276+ Brands, Amps, Woofers,
Equalizers, CD Players, Speakers, DVD, Etc. If we don't have it -
you don't want it. Please visit the website:


You don't have Eclipse, that surely does not mean I do not want
it. Even IF you could produce a 3000 watt amp for any price, let
alone $179, exactly what automotive electrical system do you expect
to power it??

Obviously there's hype in the advertising.

what's 'hype' to a seller, is ripoff to a buyer. Even if
that rating is for instantaneous power, the current
delivered to the speakers would be 250A, meaning that the
current drawn from the battery would be 360A (best case).

If anyone believes this $179 amp comes even close, I have a
wonderful bridge for sale. No, really...

-- Ron

You may be right, but there is no physical reason it can't be done.
Installers frequently use multiple banks of 1 Farad capacitors to
stiffen
the car power.
At 12V, a 1 Farad capacitor stores 12 Couloumbs of charge.
A single capacitor could provide 120 amperes for 1/10 of a second.
Ten capacitors could provide 120 amperes for about one second. Of course
the
voltage goes to zero during this interval, but it gives the idea, and the
amplifier spec is for a one ohm load.

Right. So, to provide 360A you would need 3.6Farad and to
maintain reasonable voltage while doing so you'd need at
least 10Farads. The Rockford Fosgate CPC10 1 Farad Capacitor
costs about $100 each -- about $1000 for the bank to feed
the $179 amp...

True.

And, BTW, do you really believe the $179 amp output stage
is up to the task of driving 360A for 100mSec?

In a design I'm working on, I'm using little International Rectifoer
TO-220
MOSFETS which have an Imax of 40 amperes each.

And how much are 18 of these FETs, along with the
required heatsinks and mandatory protection circuit?
Can you build an amp around them for $90 (so it can
sell for $179)?

MOSFETS don't require thermal protection, other than a thermal breaker.
I paid about $4.00 each from Digikey, so I suspect the quantity price is
around $0.50 each.

MOSFETs are not subject to thermal runaway, but they sure
require protection if you want a 350A stage to be trouble
free. Putting a circuit breaker in the signal path is not
a good idea, even in a $179 amplifier. However, we're
getting to the nit-picking stage real fast here...

I guess my point is that at this price point, it's highly
likely the 3KW spec is a lie. Don't you agree with that?

-- Ron



While it's still possible, or likely, that the amp spec is not truthful,
look at the situation from this pov: A young adult male has a choice of
buying this stuff from Nexxon, or from another source, perhaps eBay,
where
the seller may sell defective equipment, and/or not honor the warranty.

In this case, Nexxon has committed themselves to an established
arbitration
process with the consequence of adverse publicity for them, should they
scoff the result of the mediation.

Wouldn't you feel more comfortable referring the young adult male who
came
to you for advice to these people?

To be honest, I would tell the young adult that the spec
is, in all likelyhood (like, 99.999% likely) false. That
he doesn't need 3000W (or even 300W, for that matter)
and that he should go to an honest provider.

It doesn't mean we have to take a ride in the car. I can't stand these
rigs
when they come down my street.

You got me there :-).

-- Ron

He probably wouldn't hear a word you say, with his level of hearing damage
and comprehension.