I was covering that in design, IMO car speakers should
be designed to withstand the elements common in a car.

Back when Boston Acoustics came out with car speakers
the first generation used a kind of a clear plastic cone, after
a year or more the cones would try out and youcould put
your finger through them like a stale cracker.....

When they fixed that the next generation ALL of the foam
surrounds rotted away after time....

Eventually they learned ..!! ha ha

Boston isnt the only one that LEARNED the hard way
there were many, and some that havent yet... ;-)

Eddie

Nousaine wrote:

Eddie Runner

...snip....The ones where the customer just play the damn things too loud
are typicly burned coils, but we probably see (in the bays) way
more of other types of abuse on the drivers as well....

I see what Liz is saying, and you work in a lab more than a bay so
you may not see what real installers see... But what we see isnt really
what Liz thinks it is (IMO).....

Eddie Runner

Of course we're also ignoring environmental damage (temperature cycling, dirt,
ultraviolet light, moisture) as well.

"Kevin Murray" wrote:




"Nousaine" wrote:
snip

If the speaker "bottoms" meaning striking some part of the basket it is
often
already damaged.

snip


What do you mean by "striking some part of the basket?" I was referring to
the
motor assembly. I'm sure it's possible but I've yet to see a woofer damaged
from
a few whacks against the pole piece. I would think that if the diaphragm
itself
were to strike the basket, the damage would be assured and catastrophic.

I'm thinking you mean whacks against the back plate. But yes I've encountered 2
models recently where the damage sounded simply like a rubbing voice coil
and/or tinsel lead clicks but dissecting the driver revealed windings knocked
off the rear of the former and a deformed former end.

Tinsel leads hitting the cone are a clicking phenomenon. Cone hitting the
basket is rare but seldom catastrophic; most cones will deform without
permanent damage. In the catastrophic case we usually get a broken neck joint
at the coil former/cone.

The other possibilty is the spider hitting the basket; yes, its rare but there
are some designs where this can happen.

Speakers are rated in watts in order to tell you how much electrical power
they
can dissipate. Over 95% of the power delivered to a loudspeaker is
dissipated as
heat by it's resistive element and can quickly barbecue the voice coil.
Reactive
power (V-A) is what does all the work in a speaker. Since the reactive
power is
not converted to heat, the maximum V-A delivered to a speaker will vary
depending on several things such as enclosure type, signal frequency, and
driver
x-max among others. In this case the driver will reach it's excursion
limit and
mechanically destroy itself.

Since your average loudspeaker is only about 5% efficient at best, it's
satisfactory to only provide it's maximum power rating in watts. If a
speaker
bottoms out it will sound like crap and the listener will turn down the
volume.
This inherent "built-in protection" protects the speaker from mechanical
damage
resulting from excessive V-A.

5%? You're being kind...

Since EVERYONE was against me, I
sometimes argued against 5 or 6 guys at the same time, it was
overwhelming but I stuck it out and eventually won just about everyone
over to the truth....

Yeah, but that's like heaven to you.

No Ghee, you and Fred are morons. Do you not run a crossover on a sub? Are
you that dumb? Let's say you run your crossover unusually high at 140Hz,
do
you consider that high frequency? We are talking application here, not
what
a sub could potentially do in a lab if the conditions are right.

Maybe he's talking about harmonics?

But I think if you're getting harmonics of that amplitude and that
frequency, standing waves are the least of your problems...

yes it was some of the most fun online I have ever had...

MZ wrote:

Since EVERYONE was against me, I
sometimes argued against 5 or 6 guys at the same time, it was
overwhelming but I stuck it out and eventually won just about everyone
over to the truth....

Yeah, but that's like heaven to you.

Like I said, "at best." You never know when someone has come up with a yet
unknown but more efficient design. I was covering my ass really.

"MZ" wrote in message
...
Speakers are rated in watts in order to tell you how much electrical power
they
can dissipate. Over 95% of the power delivered to a loudspeaker is
dissipated as
heat by it's resistive element and can quickly barbecue the voice coil.
Reactive
power (V-A) is what does all the work in a speaker. Since the reactive
power is
not converted to heat, the maximum V-A delivered to a speaker will vary
depending on several things such as enclosure type, signal frequency, and
driver
x-max among others. In this case the driver will reach it's excursion
limit and
mechanically destroy itself.

Since your average loudspeaker is only about 5% efficient at best, it's
satisfactory to only provide it's maximum power rating in watts. If a
speaker
bottoms out it will sound like crap and the listener will turn down the
volume.
This inherent "built-in protection" protects the speaker from mechanical
damage
resulting from excessive V-A.

5%? You're being kind...

What's the most fun you've had online...?

"Eddie Runner" wrote:

yes it was some of the most fun online I have ever had...

im not gonna say

Kevin Murray wrote:

What's the most fun you've had online...?

"Eddie Runner" wrote:

yes it was some of the most fun online I have ever had...

My guess is it involves the name "Paris Hilton"...

--
Mark
remove "remove" and "spam" to reply

"Eddie Runner" wrote in message
...
im not gonna say

Kevin Murray wrote:

What's the most fun you've had online...?

"Eddie Runner" wrote:

yes it was some of the most fun online I have ever had...

"MZ" pam
wrote:

No Ghee, you and Fred are morons. Do you not run a crossover on a sub? Are
you that dumb? Let's say you run your crossover unusually high at 140Hz,
do
you consider that high frequency? We are talking application here, not
what
a sub could potentially do in a lab if the conditions are right.

Maybe he's talking about harmonics?

But I think if you're getting harmonics of that amplitude and that
frequency, standing waves are the least of your problems...

In a 2600 ft3 room the standing wave region runs from 25-300 Hz. In a smaller
car such as a Corvette, CRX, Acura Integra this is shifted up an octave to
roughly 60-600 Hz. In a larger car it drops somewhat....but it's very common to
have standing wave effects at 140 Hz in a vehicle.

"MZ" wrote in

Maybe he's talking about harmonics?

But I think if you're getting harmonics of that amplitude and that
frequency, standing waves are the least of your problems...


I considered harmonics but came to basically the same conclusion that if you
have harmonics that are that bad then something else is wrong. I also
considered the source, Ghee, and thought that he probably doesn't even know
what a harmonic is.

Les

On 25 Mar 2004 02:10:00 GMT, (Nousaine) wrote:

"MZ" pam
wrote:

No Ghee, you and Fred are morons. Do you not run a crossover on a sub? Are
you that dumb? Let's say you run your crossover unusually high at 140Hz,
do
you consider that high frequency? We are talking application here, not
what
a sub could potentially do in a lab if the conditions are right.

Maybe he's talking about harmonics?

But I think if you're getting harmonics of that amplitude and that
frequency, standing waves are the least of your problems...

In a 2600 ft3 room the standing wave region runs from 25-300 Hz. In a smaller
car such as a Corvette, CRX, Acura Integra this is shifted up an octave to
roughly 60-600 Hz. In a larger car it drops somewhat....but it's very common to
have standing wave effects at 140 Hz in a vehicle.

I think the standing waves discussion originally centered on whether
you could find them *inside* an enclosure, and whether damping
material would affect them. Whether or not they're present inside the
vehicle, I think it's safe to say that the volume inside a subwoofer
enclosure is so small as to preclude the formation of standing waves
inside the box.

Scott Gardner

(Scott Gardner) wrote:



On 25 Mar 2004 02:10:00 GMT, (Nousaine) wrote:

"MZ" pam
wrote:

No Ghee, you and Fred are morons. Do you not run a crossover on a sub?
Are
you that dumb? Let's say you run your crossover unusually high at 140Hz,
do
you consider that high frequency? We are talking application here, not
what
a sub could potentially do in a lab if the conditions are right.

Maybe he's talking about harmonics?

But I think if you're getting harmonics of that amplitude and that
frequency, standing waves are the least of your problems...

In a 2600 ft3 room the standing wave region runs from 25-300 Hz. In a
smaller
car such as a Corvette, CRX, Acura Integra this is shifted up an octave to
roughly 60-600 Hz. In a larger car it drops somewhat....but it's very common
to
have standing wave effects at 140 Hz in a vehicle.

I think the standing waves discussion originally centered on whether
you could find them *inside* an enclosure, and whether damping
material would affect them. Whether or not they're present inside the
vehicle, I think it's safe to say that the volume inside a subwoofer
enclosure is so small as to preclude the formation of standing waves
inside the box.

Scott Gardner

Agreed; standing waves at bass frequencies inside an enclosure are irrelevant
to al but the largest enclosures....say 25 ft3.

"thelizman" wrote in message
...
Tha Ghee wrote:
"thelizman" wrote in message
...

are you saying there are no standing waves in sub encs.??

Not at subwoofer frequencies. Prove me wrong.

yes there are, if there were not then what's the purpose of fiberfill, to
reduce standing waves, and make the enc. seem bigger.

show me data where there are no standing waves in enc. since you're all
knowing.

"Les" wrote in message
m...

"Tha Ghee" wrote in message if you have a metal
cone
sub there can be hi-freq content. look at the lab
graphs, so he's not a moron you may be.


No Ghee, you and Fred are morons. Do you not run a crossover on a sub? Are
you that dumb? Let's say you run your crossover unusually high at 140Hz,
do
you consider that high frequency? We are talking application here, not
what
a sub could potentially do in a lab if the conditions are right.

Les

were are not morons, there are subs that you can run without x-overs were
talking concepts that's why I mentioned this.

"Nousaine" wrote in message
...
"MZ" pam

Maybe he's talking about harmonics?

But I think if you're getting harmonics of that amplitude and that
frequency, standing waves are the least of your problems...

In a 2600 ft3 room the standing wave region runs from 25-300 Hz. In a
smaller
car such as a Corvette, CRX, Acura Integra this is shifted up an octave to
roughly 60-600 Hz. In a larger car it drops somewhat....but it's very
common to
have standing wave effects at 140 Hz in a vehicle.

if you look at the graphs of some subs they can play up to 2k or so.

In a 2600 ft3 room the standing wave region runs from 25-300 Hz. In a
smaller
car such as a Corvette, CRX, Acura Integra this is shifted up an octave
to
roughly 60-600 Hz. In a larger car it drops somewhat....but it's very
common to
have standing wave effects at 140 Hz in a vehicle.

if you look at the graphs of some subs they can play up to 2k or so.

The primary breakup mode of most subs are much much lower than that. There
may be a few that could play up high (maybe some of those aluminum jobs?),
but the impedance is often much higher up there. Got any examples of subs
that don't break up until 2kHz and still have a reasonably low impedance
there?

"Tha Ghee" wrote in message
were are not morons, there are subs that you can run without x-overs were
talking concepts that's why I mentioned this.


Why would you want to run the sub without a crossover?
We are not talking conepts here, we are talking what is actually going to
happen in the vehicle. The OP asked a "what will this actually do?" type
question and you respond, in your broken english, with some theory that
could potentially happen, maybe, if you are a MORON and don't know how to
setup a subwoofer system.


Les

"MZ" wrote in message
...
In a 2600 ft3 room the standing wave region runs from 25-300 Hz. In a
smaller
car such as a Corvette, CRX, Acura Integra this is shifted up an
octave
to
roughly 60-600 Hz. In a larger car it drops somewhat....but it's very
common to
have standing wave effects at 140 Hz in a vehicle.

if you look at the graphs of some subs they can play up to 2k or so.

The primary breakup mode of most subs are much much lower than that.
There
may be a few that could play up high (maybe some of those aluminum jobs?),
but the impedance is often much higher up there. Got any examples of subs
that don't break up until 2kHz and still have a reasonably low impedance
there?

The Aura Force 10s and Dynaudio

"Les" wrote in message
...

"Tha Ghee" wrote in message
were are not morons, there are subs that you can run without x-overs
were
talking concepts that's why I mentioned this.


Why would you want to run the sub without a crossover?
We are not talking conepts here, we are talking what is actually going to
happen in the vehicle. The OP asked a "what will this actually do?" type
question and you respond, in your broken english, with some theory that
could potentially happen, maybe, if you are a MORON and don't know how to
setup a subwoofer system.


Les

if you read most CA mags they say you can run certain subs without a x-over
just face it away from the front. ok Les and you're so eloquent can I be
like you when I'm near 80??

Which dynaudio?

--
Mark
remove "remove" and "spam" to reply

"Tha Ghee" wrote in message
...
"MZ" wrote in message
...
In a 2600 ft3 room the standing wave region runs from 25-300 Hz. In
a
smaller
car such as a Corvette, CRX, Acura Integra this is shifted up an
octave
to
roughly 60-600 Hz. In a larger car it drops somewhat....but it's
very
common to
have standing wave effects at 140 Hz in a vehicle.

if you look at the graphs of some subs they can play up to 2k or so.

The primary breakup mode of most subs are much much lower than that.
There
may be a few that could play up high (maybe some of those aluminum
jobs?),
but the impedance is often much higher up there. Got any examples of
subs
that don't break up until 2kHz and still have a reasonably low impedance
there?

The Aura Force 10s and Dynaudio

if you read most CA mags they say you can run certain subs without a
x-over
just face it away from the front. ok Les and you're so eloquent can I be
like you when I'm near 80??


You can. But that doesn't mean they're responsive that high. Also, getting
back to the original topic, if you're trying to attenuate high frequencies
by facing it away from the front, then why would you be concerned with
standing waves?

Tha Ghee wrote:

if you read most CA mags they say you can run certain subs without a x-over
just face it away from the front. ok Les and you're so eloquent can I be
like you when I'm near 80??

Without a crossover, it is not longer a subwoofer. Face it away from the
front? As if high frequency sounds didn't reflect...

....just when I thought you couldn't get any more stupid, you surprise me.

--
thelizman "I didn't steal the FAQ either"

Before you ask a question, check the FAQs for this newsgroup at
http://www.mobileaudio.com/rac-faq. It contains over a decade and
a half of knowledge.

teamROCS Car Audio Forums http://www.teamrocs.com/caraudio/
teamROCS Car Audio News http://www.teamrocs.com/news/
"It's about the music, stupid"

This post is Copyright (C) 2004. Reproduction of its content anywhere
other than usenet without the express written permission of the author
is forbidden.

"MZ" wrote in message
...
Which dynaudio?

--
Mark
remove "remove" and "spam" to reply

the 8" & 10" went up the mid 1khz, and if memory servers me correctly the
review said you could use them in a 2 way system in a pinch.

"MZ" wrote in message
...
if you read most CA mags they say you can run certain subs without a
x-over
just face it away from the front. ok Les and you're so eloquent can I
be
like you when I'm near 80??


You can. But that doesn't mean they're responsive that high. Also,
getting
back to the original topic, if you're trying to attenuate high frequencies
by facing it away from the front, then why would you be concerned with
standing waves?

Those are two different topic, standing waves and high freq. are not what I
discussing, just that some subs can play high freq. that's all.

"thelizman" wrote in message
...
Tha Ghee wrote:

if you read most CA mags they say you can run certain subs without a
x-over
just face it away from the front. ok Les and you're so eloquent can I
be
like you when I'm near 80??

Without a crossover, it is not longer a subwoofer. Face it away from the
front? As if high frequency sounds didn't reflect...

...just when I thought you couldn't get any more stupid, you surprise me.

--
thelizman "I didn't steal the FAQ either"

Before you ask a question, check the FAQs for this newsgroup at
http://www.mobileaudio.com/rac-faq. It contains over a decade and
a half of knowledge.

teamROCS Car Audio Forums http://www.teamrocs.com/caraudio/
teamROCS Car Audio News http://www.teamrocs.com/news/
"It's about the music, stupid"

This post is Copyright (C) 2004. Reproduction of its content anywhere
other than usenet without the express written permission of the author
is forbidden.

so just because it has no outside filtering it changes what it is, explain
this to me?? they do but they will get absorbed more easily then low freq.
content. not as much as you do, I didn't know someone could spout this much
crap and no one call them on it.

You brought up high frequencies to demonstrate that standing waves can be an
issue. So the two are inseparable. My question stands: if you're trying to
attenuate high frequencies by turning the driver around, why would you be
concerned with standing waves?

--
Mark
remove "remove" and "spam" to reply

"Tha Ghee" wrote in message
...
"MZ" wrote in message
...
if you read most CA mags they say you can run certain subs without a
x-over
just face it away from the front. ok Les and you're so eloquent can I
be
like you when I'm near 80??


You can. But that doesn't mean they're responsive that high. Also,
getting
back to the original topic, if you're trying to attenuate high
frequencies
by facing it away from the front, then why would you be concerned with
standing waves?

Those are two different topic, standing waves and high freq. are not what
I
discussing, just that some subs can play high freq. that's all.

"MZ" wrote in message
...
You brought up high frequencies to demonstrate that standing waves can be
an
issue. So the two are inseparable. My question stands: if you're trying
to
attenuate high frequencies by turning the driver around, why would you be
concerned with standing waves?

--
standing waves have nothing to do with high freq. if I said that it was a
mistake.