"John Durbin" wrote in message
...
Resonant frequency of the box changes the output of the system at that
frequency, also affects the driver's impedance as it appears to the amp
driving the system, etc. If you sweep the driver impedance curve in free
air & then again in the box and compare the two, you will see a large
change. Think about it this way: in open air the driver compliance is a
combination of factors that includes the relative stiffness of the spider
and the surround. When you put it in a box, the effect of the air mass
(air spring if you will) changes that compliance and your system tuning
changes with it.

This happens in a vented box too but is more complicated because the air
mass behaves differently at port resonance than it does above it.

And I thaught I was asking a simple question. :-)
I've been following the debate with interest.
I think I can now waffle with the best of them, even though I wouldn't know
what I was talking about. :-)
Mike.

"John Durbin" wrote in message
...
Resonant frequency of the box changes the output of the system at that
frequency, also affects the driver's impedance as it appears to the amp
driving the system, etc. If you sweep the driver impedance curve in free
air & then again in the box and compare the two, you will see a large
change. Think about it this way: in open air the driver compliance is a
combination of factors that includes the relative stiffness of the spider
and the surround. When you put it in a box, the effect of the air mass
(air spring if you will) changes that compliance and your system tuning
changes with it.

Yes, I know that, but common sense would say that putting ANYTHING in the
enclsoure would mean LESS air therefore a tighter "spring", like a SMALLER
BOX, NOT A LARGER BOX. I guess this is why this saying "putting fill in a
box will make it seem like a larger box" just seemed to go against common
sense to me.

But I do understand the first part of your explanation. By adding fill you
change the resonant frequency of the volume of air in the enclosure. This
will have an effect (small I would imagine) on the frequency response of the
system. This makes sense.

Thank you for that explanation.


MOSFET




This happens in a vented box too but is more complicated because the air
mass behaves differently at port resonance than it does above it.

JD

MOSFET wrote:

If you've made a box with an internal

volume of .75 cu ft, as recommended by the manufacturer of the subwoofer
you're using (let's assume that the basket volume is a non-issue here),
then adding polyfill stuffing would essentially increase the intermal
volume of the box - lowering the desired tuned frequency.


Yes, Tony, but the tuned frequency of what? The volume of air inside the
enclosure? In a sealed enclosure, what effect does the tuning frequency
of the volume of air inside the enclosure make any difference to
anything? That has been my entire point this whole thread. My
understanding has always been that in a sealed enclosure, the volume of
air inside a box acts as a spring to the woofer. That's it. I would
think that in a well constructed enclosure the volume of air inside a box
would have the same air pressure as the outside air. How would the
resonant frequency of this volume of air have any bearing on anything!
I'm sorry, I just don't understand. I'm so confused!

Nick

Actually, the effect is not "small" at all. In theory the effect is like
having a 40% larger box. In practice, however it comes out to closer to 20%.

- RG


"MOSFET" wrote in message
...

"John Durbin" wrote in message
...
Resonant frequency of the box changes the output of the system at that
frequency, also affects the driver's impedance as it appears to the amp
driving the system, etc. If you sweep the driver impedance curve in free
air & then again in the box and compare the two, you will see a large
change. Think about it this way: in open air the driver compliance is a
combination of factors that includes the relative stiffness of the spider
and the surround. When you put it in a box, the effect of the air mass
(air spring if you will) changes that compliance and your system tuning
changes with it.

Yes, I know that, but common sense would say that putting ANYTHING in the
enclsoure would mean LESS air therefore a tighter "spring", like a SMALLER
BOX, NOT A LARGER BOX. I guess this is why this saying "putting fill in a
box will make it seem like a larger box" just seemed to go against common
sense to me.

But I do understand the first part of your explanation. By adding fill
you change the resonant frequency of the volume of air in the enclosure.
This will have an effect (small I would imagine) on the frequency response
of the system. This makes sense.

Thank you for that explanation.


MOSFET




This happens in a vented box too but is more complicated because the air
mass behaves differently at port resonance than it does above it.

JD

MOSFET wrote:

If you've made a box with an internal

volume of .75 cu ft, as recommended by the manufacturer of the subwoofer
you're using (let's assume that the basket volume is a non-issue here),
then adding polyfill stuffing would essentially increase the intermal
volume of the box - lowering the desired tuned frequency.


Yes, Tony, but the tuned frequency of what? The volume of air inside
the enclosure? In a sealed enclosure, what effect does the tuning
frequency of the volume of air inside the enclosure make any difference
to anything? That has been my entire point this whole thread. My
understanding has always been that in a sealed enclosure, the volume of
air inside a box acts as a spring to the woofer. That's it. I would
think that in a well constructed enclosure the volume of air inside a
box would have the same air pressure as the outside air. How would the
resonant frequency of this volume of air have any bearing on anything!
I'm sorry, I just don't understand. I'm so confused!

Nick

BTW, the "spring" effects of air are not constant. Refer to my previous post
on adiabatic versus isothermal. This changes the "characteristic" of the air
considerably. Just remember, the earth is not flat ....

- RG

"MOSFET" wrote in message
...

"John Durbin" wrote in message
...
Resonant frequency of the box changes the output of the system at that
frequency, also affects the driver's impedance as it appears to the amp
driving the system, etc. If you sweep the driver impedance curve in free
air & then again in the box and compare the two, you will see a large
change. Think about it this way: in open air the driver compliance is a
combination of factors that includes the relative stiffness of the spider
and the surround. When you put it in a box, the effect of the air mass
(air spring if you will) changes that compliance and your system tuning
changes with it.

Yes, I know that, but common sense would say that putting ANYTHING in the
enclsoure would mean LESS air therefore a tighter "spring", like a SMALLER
BOX, NOT A LARGER BOX. I guess this is why this saying "putting fill in a
box will make it seem like a larger box" just seemed to go against common
sense to me.

But I do understand the first part of your explanation. By adding fill
you change the resonant frequency of the volume of air in the enclosure.
This will have an effect (small I would imagine) on the frequency response
of the system. This makes sense.

Thank you for that explanation.


MOSFET




This happens in a vented box too but is more complicated because the air
mass behaves differently at port resonance than it does above it.

JD

MOSFET wrote:

If you've made a box with an internal

volume of .75 cu ft, as recommended by the manufacturer of the subwoofer
you're using (let's assume that the basket volume is a non-issue here),
then adding polyfill stuffing would essentially increase the intermal
volume of the box - lowering the desired tuned frequency.


Yes, Tony, but the tuned frequency of what? The volume of air inside
the enclosure? In a sealed enclosure, what effect does the tuning
frequency of the volume of air inside the enclosure make any difference
to anything? That has been my entire point this whole thread. My
understanding has always been that in a sealed enclosure, the volume of
air inside a box acts as a spring to the woofer. That's it. I would
think that in a well constructed enclosure the volume of air inside a
box would have the same air pressure as the outside air. How would the
resonant frequency of this volume of air have any bearing on anything!
I'm sorry, I just don't understand. I'm so confused!

Nick

Actually, the effect is not "small" at all. In theory the effect is like
having a 40% larger box. In practice, however it comes out to closer to
20%.

- RG

By small, I meant small change in the overall performance of the system
(frequency response curve for instance). But I see your point.

MOSFET

Nick,

Check out http://www.bcae1.com under chapter 115, Speaker Respose Curves.
There's graph (and explanation) about 3/4 of the way through the chapter
that shows the response curve for an unstuffed box vs. a stuffed one. Just
FYI.

Tony

Thanks Tony. Aren't you a fountain of information!!!

The two curves (box with Polyfill and box without) are nearly identical so,
again, this seems to prove what I believe you said before (and what I said),
Polyfill makes very little difference.

I think we can now put this one to bed thanks to you.

Nick

"Tony F" wrote in message
...
Nick,

Check out http://www.bcae1.com under chapter 115, Speaker Respose Curves.
There's graph (and explanation) about 3/4 of the way through the chapter
that shows the response curve for an unstuffed box vs. a stuffed one.
Just FYI.

Tony

Correct, it is not a huge effect but measurable & audible if you use
stuffing that has enough mass. People tend to use polyfill because it's
readily available but wool or fiberglass will give you better results.

If you put too much in you actually interfere with the resonance of the
air & stuffing mass & it works against you instead of helping squeeze a
little more LF extension from the system.

JD

MOSFET wrote:
"John Durbin" wrote in message
...

Resonant frequency of the box changes the output of the system at that
frequency, also affects the driver's impedance as it appears to the amp
driving the system, etc. If you sweep the driver impedance curve in free
air & then again in the box and compare the two, you will see a large
change. Think about it this way: in open air the driver compliance is a
combination of factors that includes the relative stiffness of the spider
and the surround. When you put it in a box, the effect of the air mass
(air spring if you will) changes that compliance and your system tuning
changes with it.


Yes, I know that, but common sense would say that putting ANYTHING in the
enclsoure would mean LESS air therefore a tighter "spring", like a SMALLER
BOX, NOT A LARGER BOX. I guess this is why this saying "putting fill in a
box will make it seem like a larger box" just seemed to go against common
sense to me.

But I do understand the first part of your explanation. By adding fill you
change the resonant frequency of the volume of air in the enclosure. This
will have an effect (small I would imagine) on the frequency response of the
system. This makes sense.

Thank you for that explanation.


MOSFET




This happens in a vented box too but is more complicated because the air
mass behaves differently at port resonance than it does above it.

JD

MOSFET wrote:


If you've made a box with an internal


volume of .75 cu ft, as recommended by the manufacturer of the subwoofer
you're using (let's assume that the basket volume is a non-issue here),
then adding polyfill stuffing would essentially increase the intermal
volume of the box - lowering the desired tuned frequency.


Yes, Tony, but the tuned frequency of what? The volume of air inside the
enclosure? In a sealed enclosure, what effect does the tuning frequency
of the volume of air inside the enclosure make any difference to
anything? That has been my entire point this whole thread. My
understanding has always been that in a sealed enclosure, the volume of
air inside a box acts as a spring to the woofer. That's it. I would
think that in a well constructed enclosure the volume of air inside a box
would have the same air pressure as the outside air. How would the
resonant frequency of this volume of air have any bearing on anything!
I'm sorry, I just don't understand. I'm so confused!

Nick

"Standing waves are not usually a big problem in a subwoofer because it is
usually crossed over. In other situations, like home speakers, poly-fill can
be used to damp standing waves. In home speakers, the woofer is often used
to reproduce a wider frequency range than it would be in a subwoofer. This
creates the opportunity for standing waves to create problems. The
wavelength is too long in the lowest frequencies to cause a problem but
frequencies above 300 or 400hz will start to cause problems."

I reckon so ....

There goes YOUR theory and validation on what polyfill does or doesn't do in
a subwoofer box .... right from the fountain of information itself :-)

- RG


"MOSFET" wrote in message
m...
Thanks Tony. Aren't you a fountain of information!!!

The two curves (box with Polyfill and box without) are nearly identical
so, again, this seems to prove what I believe you said before (and what I
said), Polyfill makes very little difference.

I think we can now put this one to bed thanks to you.

Nick

"Tony F" wrote in message
...
Nick,

Check out http://www.bcae1.com under chapter 115, Speaker Respose Curves.
There's graph (and explanation) about 3/4 of the way through the chapter
that shows the response curve for an unstuffed box vs. a stuffed one.
Just FYI.

Tony

In article ,
John Durbin wrote:

If you put too much in you actually interfere with the resonance of the
air & stuffing mass & it works against you instead of helping squeeze a
little more LF extension from the system.

JD


I concur. There have been instances where I have had to play with
certain amounts of stuffing in an enclosure to get my desired response,
whether in my head or not. This seems moreso with midbass/mid drivers.

--
-Cyrus

*coughcasaucedoprodigynetcough*

I concur. There have been instances where I have had to play with
certain amounts of stuffing in an enclosure to get my desired response,
whether in my head or not. This seems moreso with midbass/mid drivers.

This may have more to do with standing wave cancellation than anything else
as RG has pointed out (in a snippy way) that standing waves become more of a
problem in the midrange-midbass region (300-400 Hz).

Just a thought.

MOSFET

That's funny because there sure are a WHOLE LOTTA FOLKS out there who seem
VERY concerned about standing waves in their sub enclosure. For instance:

http://www.the12volt.com/caraudio/boxes2.asp

I guess they are all wrong according to you as standing waves are not a
problem below 300-400Hz.

So, to be honest, you HAVE NOT convinced me RG.

MOSFET


"RG" wrote in message
...
"Standing waves are not usually a big problem in a subwoofer because it is
usually crossed over. In other situations, like home speakers, poly-fill
can be used to damp standing waves. In home speakers, the woofer is often
used to reproduce a wider frequency range than it would be in a subwoofer.
This creates the opportunity for standing waves to create problems. The
wavelength is too long in the lowest frequencies to cause a problem but
frequencies above 300 or 400hz will start to cause problems."

I reckon so ....

There goes YOUR theory and validation on what polyfill does or doesn't do
in a subwoofer box .... right from the fountain of information itself :-)

- RG


"MOSFET" wrote in message
m...
Thanks Tony. Aren't you a fountain of information!!!

The two curves (box with Polyfill and box without) are nearly identical
so, again, this seems to prove what I believe you said before (and what I
said), Polyfill makes very little difference.

I think we can now put this one to bed thanks to you.

Nick

"Tony F" wrote in message
...
Nick,

Check out http://www.bcae1.com under chapter 115, Speaker Respose
Curves. There's graph (and explanation) about 3/4 of the way through the
chapter that shows the response curve for an unstuffed box vs. a stuffed
one. Just FYI.

Tony

Check again .... those were actually Perry Babin's words (direct quote).

- RG


"MOSFET" wrote in message
m...
That's funny because there sure are a WHOLE LOTTA FOLKS out there who seem
VERY concerned about standing waves in their sub enclosure. For instance:

http://www.the12volt.com/caraudio/boxes2.asp

I guess they are all wrong according to you as standing waves are not a
problem below 300-400Hz.

So, to be honest, you HAVE NOT convinced me RG.

MOSFET


"RG" wrote in message
...
"Standing waves are not usually a big problem in a subwoofer because it
is usually crossed over. In other situations, like home speakers,
poly-fill can be used to damp standing waves. In home speakers, the
woofer is often used to reproduce a wider frequency range than it would
be in a subwoofer. This creates the opportunity for standing waves to
create problems. The wavelength is too long in the lowest frequencies to
cause a problem but frequencies above 300 or 400hz will start to cause
problems."

I reckon so ....

There goes YOUR theory and validation on what polyfill does or doesn't do
in a subwoofer box .... right from the fountain of information itself :-)

- RG


"MOSFET" wrote in message
m...
Thanks Tony. Aren't you a fountain of information!!!

The two curves (box with Polyfill and box without) are nearly identical
so, again, this seems to prove what I believe you said before (and what
I said), Polyfill makes very little difference.

I think we can now put this one to bed thanks to you.

Nick

"Tony F" wrote in message
...
Nick,

Check out http://www.bcae1.com under chapter 115, Speaker Respose
Curves. There's graph (and explanation) about 3/4 of the way through
the chapter that shows the response curve for an unstuffed box vs. a
stuffed one. Just FYI.

Tony

In article 0W2ng.81736$iF6.11013@pd7tw2no, Matt Ion wrote:
MOSFET wrote:
There is another effect of course, a very important one. In that stuffed
enclosure
the manufacture may have specified a volume, and the stuffing acts to
increase that
volume.If you don't stuff that enclosed box, it may be too small.
Stuffing is all very different and has different effects at different
frequencies.
I make use of cotton, wool, fiberglass, and Dacron, and very important,
FOAM.

greg


OK, this might be a gap in my knowledge, but I have ALWAYS been confused by
the assertion that in a box "stuffing acts to increase that volume" to use
your words. To me, that defies the laws of physics and I flat out refuse to
use that term. I have ALWAYS believed that this was just a shorthand way of
describing the effects stuffing can have (reduced acoustical interchange
that causes problems like standing waves) which I DID address in my
explanation. By reducing sound waves bouncing around in a box, THAT IS like
having a larger box. So in a sense, I did cover that in my explanation.

Is there something else I'm missing?

Nope, you pretty much nailed it. The stuffing DOES have the effect of
slowing down the sound waves as well, which makes the box "appear"
larger to the driver (internal waves take longer to reflect back).

Stuffing does slow sound waves.
Reflecting back, really has nothing to do with anything. It just a pressure-
contraction of the box, period. I breifly read some of the posts, and its seems
very strange the reason most any speaker book might explain the most
accepted version has not been addressed. When the air is pressurized, it
heats up. When it contracts, it cools down. If you add fiber, the fiber absorbs
these transistion somewhat. When the transistions of temperature are minimized
the net effect is a reduction of pressure and contraction. Bigger box!!
Polyfill has limited effect in this area. Fiberglass works much better as
well as foam. I have got up to the theroetical increase in box size of 40%
but much less is the norm.

You can also use a heavier gas inside which will accomplish the same
bigger box effect.

greg

In article ,
"MOSFET" wrote:

I concur. There have been instances where I have had to play with
certain amounts of stuffing in an enclosure to get my desired response,
whether in my head or not. This seems moreso with midbass/mid drivers.

This may have more to do with standing wave cancellation than anything else
as RG has pointed out (in a snippy way) that standing waves become more of a
problem in the midrange-midbass region (300-400 Hz).

Just a thought.

MOSFET


I try to keep my ideas/help vague and open for a reason. Some are very
serious about their audio addictions.

Wave lengths are shorter at higher frequencies. There's more of a chance
of standing waves happening with midbass/mid drivers, as has I'm sure
been beaten to death by now. Then again there are too many factors to
even know whether or not its happening while communicating with someone
via usenet.

In any case, its just audio. I say enjoy the gear you have, your hearing
and knowledge. Nobody really cares about this sorta thing except us, as
evidenced by the last wedding reception I was at and its 'dj'.

--
-Cyrus

*coughcasaucedoprodigynetcough*

In article , Cyrus wrote:
In article ,
"MOSFET" wrote:

I concur. There have been instances where I have had to play with
certain amounts of stuffing in an enclosure to get my desired response,
whether in my head or not. This seems moreso with midbass/mid drivers.

This may have more to do with standing wave cancellation than anything else
as RG has pointed out (in a snippy way) that standing waves become more of a
problem in the midrange-midbass region (300-400 Hz).

Just a thought.

MOSFET


I try to keep my ideas/help vague and open for a reason. Some are very
serious about their audio addictions.

Wave lengths are shorter at higher frequencies. There's more of a chance
of standing waves happening with midbass/mid drivers, as has I'm sure
been beaten to death by now. Then again there are too many factors to
even know whether or not its happening while communicating with someone
via usenet.

In any case, its just audio. I say enjoy the gear you have, your hearing
and knowledge. Nobody really cares about this sorta thing except us, as
evidenced by the last wedding reception I was at and its 'dj'.

Most of the time when things sound bad, people don't say mnuch. When
it sounds good, they say more. At least thats my experiance.

Midbass and midranges. Midranges have the most effect. Its
like trying to have a speaker in the door with no sound treatment
in back of it. Its the pits. OEM speakers usually don't have anything, but
us hifi persons know better.

greg

"John Durbin" wrote in message
...
Resonance is wasted energy?

Jeez, I better dump my JBL L150A's with passive radiators & L112's with
vents, cause they rely on WASTED ENERGY to extend the usable LF response a
good half-octave and that's apparently a BAD THING.

Nice! You don't see the L150A's too often!

I too, Own a set of L112's

Chad

Nice pair of L150's going on ebay for $721 with a few hours left... you
gotta love the way these things have held their value, not to mention
how damn good they still sound.

I'm up to 3 pair of the 150A and 1 pr. of L112. One of the pair of
150A's got aborted by someone with eyebolts through the back (4 per
cabinet) so I figured I'd hang them in a dead space above the doors in
the garage, that should be sufficient to screw with the neighbors :-)

May also try throwing together a 5.1 surround system upstairs just for
the hell of it, think about three L150A's for L/C/R and a pair of L112's
on orig. JBL stands for rear surround, with 300W bridged Sony TA-55ES
amps on each of the front channels & a Sansui 717 to drive the rear
surround. Only problem is what to use for a sub to keep up with all that
- maybe the 18 some guy was selling in a 6 cu. ft. enclosure recently.

Probably cost me a wife if I build this thing & fire it up, but might be
worth it!

JD

Chad Wahls wrote:
"John Durbin" wrote in message
...

Resonance is wasted energy?

Jeez, I better dump my JBL L150A's with passive radiators & L112's with
vents, cause they rely on WASTED ENERGY to extend the usable LF response a
good half-octave and that's apparently a BAD THING.


Nice! You don't see the L150A's too often!

I too, Own a set of L112's

Chad

That's frankly amazing. $721 for a pair of 25 year old JBL speakers (let's
face it, JBL is no Martin Logan) which appear to be banged up a bit. Holy
cow! Those must be REALLY good speakers.

Some of those older JBL speakers are really great. I own a pair of JBL P10
bookshelf speakers that I bought about 15 years ago and I have NEVER yet
heard a speaker of it's size that I felt sounded better. I used to use them
(with a subwoofer, of course) on 4' sand-filled stands in my "listening
room" and the imaging was ABSOLUTELY STARTLING. To show them off I used to
play the beginning of Pink Floyd's "Time". I remember for most of my
friends, this was the first time they had ever heard two speakers
"disappear" and TRULY create a near 360 degree soundfield.

Those speakers are now relegated to surround duties in my home-theater, but
they are still going strong AND they handle all the power my Denon AVR-3600
can dish out (on a full range setting!).

I believe JBL continues to produce high-quality speakers, but I agree there
was something great about those older ones (especially when considering what
they compared to at the time).

MOSFET
"John Durbin" wrote in message
...
Nice pair of L150's going on ebay for $721 with a few hours left... you
gotta love the way these things have held their value, not to mention how
damn good they still sound.

I'm up to 3 pair of the 150A and 1 pr. of L112. One of the pair of 150A's
got aborted by someone with eyebolts through the back (4 per cabinet) so I
figured I'd hang them in a dead space above the doors in the garage, that
should be sufficient to screw with the neighbors :-)

May also try throwing together a 5.1 surround system upstairs just for the
hell of it, think about three L150A's for L/C/R and a pair of L112's on
orig. JBL stands for rear surround, with 300W bridged Sony TA-55ES amps on
each of the front channels & a Sansui 717 to drive the rear surround. Only
problem is what to use for a sub to keep up with all that - maybe the 18
some guy was selling in a 6 cu. ft. enclosure recently.

Probably cost me a wife if I build this thing & fire it up, but might be
worth it!

JD

Chad Wahls wrote:
"John Durbin" wrote in message
...

Resonance is wasted energy?

Jeez, I better dump my JBL L150A's with passive radiators & L112's with
vents, cause they rely on WASTED ENERGY to extend the usable LF response
a good half-octave and that's apparently a BAD THING.


Nice! You don't see the L150A's too often!

I too, Own a set of L112's

Chad

"MOSFET" wrote in message
m...
I believe JBL continues to produce high-quality speakers, but I agree
there was something great about those older ones (especially when
considering what they compared to at the time).

MOSFET


Their best stuff is the older stuff because that's when the consumer and
professional division ACTUALLY got along. There WAS a lot of shared
engineering. Not anymore

Chad

"John Durbin" wrote in message
...
Nice pair of L150's going on ebay for $721 with a few hours left... you
gotta love the way these things have held their value, not to mention how
damn good they still sound.

I'm up to 3 pair of the 150A and 1 pr. of L112. One of the pair of 150A's
got aborted by someone with eyebolts through the back (4 per cabinet) so I
figured I'd hang them in a dead space above the doors in the garage, that
should be sufficient to screw with the neighbors :-)

May also try throwing together a 5.1 surround system upstairs just for the
hell of it, think about three L150A's for L/C/R and a pair of L112's on
orig. JBL stands for rear surround, with 300W bridged Sony TA-55ES amps on
each of the front channels & a Sansui 717 to drive the rear surround. Only
problem is what to use for a sub to keep up with all that - maybe the 18
some guy was selling in a 6 cu. ft. enclosure recently.

Probably cost me a wife if I build this thing & fire it up, but might be
worth it!

JD



That will be a nice theater! Most of my power at the ranch comes from
Crown, with spatterings from Carver (Clair Bros. Modified) and Phase Linear
(FlameLinear).

For A sub I use an Electro Voice EVX180B in a big TL enclosure and it will
shake your bones and play flat VERY low. For aesthetics may I suggest 1-2
JBL 2245's in a big-ol enclosure? They are great drivers and will play very
L-O-W! They were used mostly in theatres as effect drivers, you will need
to find original baskets and have them reconed. Most of them have foam-rot.
Recone Kits are available. The part is C8R2245. Orange county speaker can
hook you up. I THINK the 2240 baskets are the same but I can't remember.
2240's will be easier to come across as they sold an ass load of them. The
2245 is not a power handling monster and care must be taken in setting the
HP filter for the box tuning. They have mass rings and when they unload
they go a-bounding! Don't worry about the handling though. They are quite
efficient and can handle the peaks with ease. I'm sure you know what you
are doing


Chad

Closed at $990... and this is the L150, which I think is not quite the
equal of the 150A due to difference in tweeter design plus with some
cabinet damage. That's damn near 0% depreciation regardless...

Newer JBL speakers lack any of the unique and special qualities that
make that kind of resale value stand up, my opinion. Not that they suck,
but they just lost the aura they had back then when the guys in
engineering had the reins instead of the sales & marketing dept's.

JD

MOSFET wrote:
That's frankly amazing. $721 for a pair of 25 year old JBL speakers (let's
face it, JBL is no Martin Logan) which appear to be banged up a bit. Holy
cow! Those must be REALLY good speakers.

Some of those older JBL speakers are really great. I own a pair of JBL P10
bookshelf speakers that I bought about 15 years ago and I have NEVER yet
heard a speaker of it's size that I felt sounded better. I used to use them
(with a subwoofer, of course) on 4' sand-filled stands in my "listening
room" and the imaging was ABSOLUTELY STARTLING. To show them off I used to
play the beginning of Pink Floyd's "Time". I remember for most of my
friends, this was the first time they had ever heard two speakers
"disappear" and TRULY create a near 360 degree soundfield.

Those speakers are now relegated to surround duties in my home-theater, but
they are still going strong AND they handle all the power my Denon AVR-3600
can dish out (on a full range setting!).

I believe JBL continues to produce high-quality speakers, but I agree there
was something great about those older ones (especially when considering what
they compared to at the time).

MOSFET
"John Durbin" wrote in message
...

Nice pair of L150's going on ebay for $721 with a few hours left... you
gotta love the way these things have held their value, not to mention how
damn good they still sound.

I'm up to 3 pair of the 150A and 1 pr. of L112. One of the pair of 150A's
got aborted by someone with eyebolts through the back (4 per cabinet) so I
figured I'd hang them in a dead space above the doors in the garage, that
should be sufficient to screw with the neighbors :-)

May also try throwing together a 5.1 surround system upstairs just for the
hell of it, think about three L150A's for L/C/R and a pair of L112's on
orig. JBL stands for rear surround, with 300W bridged Sony TA-55ES amps on
each of the front channels & a Sansui 717 to drive the rear surround. Only
problem is what to use for a sub to keep up with all that - maybe the 18
some guy was selling in a 6 cu. ft. enclosure recently.

Probably cost me a wife if I build this thing & fire it up, but might be
worth it!

JD

Chad Wahls wrote:

"John Durbin" wrote in message
...


Resonance is wasted energy?

Jeez, I better dump my JBL L150A's with passive radiators & L112's with
vents, cause they rely on WASTED ENERGY to extend the usable LF response
a good half-octave and that's apparently a BAD THING.


Nice! You don't see the L150A's too often!

I too, Own a set of L112's

Chad