sk8erteck

(this might be a repost, it never showed up on my ISP's server)

Alright i know that clipping is bad and such, but my subwoofer amp is
constantly clipping and not distorting at all. It isn't even enough to
trigger the 'warning' light on the woofer. When I put the amp in
bridged mode and turn the gain down, the amp doesn't clip but i get
distortion and the warning light on the woofer turns on. The only way
to reduce this is to turn the gain way down, to levels that are not
anywhere near enough or near where it was before the bridge. I've been
running it unbridged with the clipping for about 2 weeks, is this bad?
Why is it clipping but sounding fine? Why does it not sound fine in
bridge mode? Am i damaging the woofer/amp?

Here's what i am working withnot great but it was provided with the gig)
B-52 Band-Pass Subwooofer rated 550 watts
Behringer EP1500, rated 260watts at 8ohms in stereo mode, 800 watts in
bridged mono

Highs + Mids are on another EP1500 hooked up to Peaveys, but that setup
seems to be working fine. As of now there is no crossover, I have the
subwooferamp running off of the booth output of my mixer. A behringer
crossover(i cant remember the model off the top of my head) has been ordered
and should be in this week.

I'd estimate that the woofer is pushing 250+ watts in stereo mode, but
only about 100 in bridged mono without distorting. Since it is rated
550, how can I get more out of it?

thanks in advance




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citronzx

"sk8erteck" <sk8erteck@SPAMNOhotmail.com> wrote in message
news:4026ff0f$1_3@corp.newsgroups.com...
> (this might be a repost, it never showed up on my ISP's server)
>
> Alright i know that clipping is bad and such, but my subwoofer amp is
> constantly clipping and not distorting at all. It isn't even enough to
> trigger the 'warning' light on the woofer. When I put the amp in
> bridged mode and turn the gain down, the amp doesn't clip but i get
> distortion and the warning light on the woofer turns on. The only way
> to reduce this is to turn the gain way down, to levels that are not
> anywhere near enough or near where it was before the bridge. I've been
> running it unbridged with the clipping for about 2 weeks, is this bad?
> Why is it clipping but sounding fine? Why does it not sound fine in
> bridge mode? Am i damaging the woofer/amp?
>
> Here's what i am working withnot great but it was provided with the gig)
> B-52 Band-Pass Subwooofer rated 550 watts
> Behringer EP1500, rated 260watts at 8ohms in stereo mode, 800 watts in
> bridged mono
>
> Highs + Mids are on another EP1500 hooked up to Peaveys, but that setup
> seems to be working fine. As of now there is no crossover, I have the
> subwooferamp running off of the booth output of my mixer. A behringer
> crossover(i cant remember the model off the top of my head) has been
ordered
> and should be in this week.
>
> I'd estimate that the woofer is pushing 250+ watts in stereo mode, but
> only about 100 in bridged mono without distorting. Since it is rated
> 550, how can I get more out of it?
>
> thanks in advance
>
>
Could you explain how you have determined that the amplifier is clipping?
Clipping is a form of distortion. It happens when an amplifier stage is
driven up to and beyond the supply voltage (or current if a current
amplifier). Imagine that you are feeding an amplifier sine wave and
watching the output on an oscilloscope. Well, if all is well you see a sine
wave of larger amplitude on the scope. If the amplifier is clipping the
tops of the waves will be flattened off because the amplifier cannot supply
enough power to form the tops of the peaks; it clips them off.

If a light on the amplifier is telling you that it is clipping the you
should turn it down until the light goes off. If this isn't loud enough
then you should consider getting a more powerful amplifier. A clipping
amplifier probably will not damage the speaker, especially if it is not even
at a level that you consider loud enough. Really, the only was that you are
likely to damage a subwoofer is to drive it too loud and either damage the
voice coil by over heating it or by causing the woofer to move in and out
too far, again with too much power. I have actually seen a melted voice
coil so I know that it can happen.

I am a bit concerned that you say that you are not using a crossover. This
is not an optional device. I'm not really very familiar with musical
instrument equipment but if there is not a crossover built into the woofer
then I would suggest not using it until you have one. Woofers are rugged
and not as susceptible to being damaged by too high of a frequency as a
tweeter is to being driven by too low of one but it sill is not a good idea.

Lucy Explainin

"citronzx" <dillonbaca@earthlink.net> wrote in message
news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...
"A clipping amplifier probably will not damage the speaker, especially if it
is not even at a level that you consider loud enough".

Not.

Clipping involves (as you describe) a squaring off of the wave, or a leading
positive and negative DC edge. This WILL cause damage to a loudspeaker in
the form of damage to the voicecoil - and it won't take long to manifest
itself. For this very reason it is SAFER to overdrive a small loudspeaker
with a big amp and keeping the signal clean and non clipped.

Those BehMINGER amps are not really man enough and Ive found them quite fun
run side by side with the likes of Matrix and Crown. "I can't hear it" being
the common comment. So don't trust the rated output. Experience says that if
its clipping and it does not sound loud enough then it's just not man
enough.

sk8erteck

I know its clipping based on the clipping light. I'm familar with what you
said, but it sounds better when its clipping versus not clipping in higher
powered mode(bridged mono) at the same sound levels. That doesn't make sense
to me, espesically when i came close to blowing the speaker(warning light on
the speaker came full on) in bridged mode. The output was no louder than
when it is clipping.

I know a crossover is needed, I had one ordered as soon as I got the gig.
There is one built into the woofer, but im thinking that i might get more
power out of the amp with a crossover, since it doesnt have to amplify the
highs + mids. That and it will give me more protection for the Peaveys, a
guest DJ already blew one. (voice coil burnt) We thought that the other one
was blown, but when we went up to look at it, it must have been hit by a
basketball or something because the front grill was bent into the cone.
Pulled the grill off and it sounded fine.


"citronzx" <dillonbaca@earthlink.net> wrote in message
news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...

> Could you explain how you have determined that the amplifier is clipping?
> Clipping is a form of distortion. It happens when an amplifier stage is
> driven up to and beyond the supply voltage (or current if a current
> amplifier). Imagine that you are feeding an amplifier sine wave and
> watching the output on an oscilloscope. Well, if all is well you see a
sine
> wave of larger amplitude on the scope. If the amplifier is clipping the
> tops of the waves will be flattened off because the amplifier cannot
supply
> enough power to form the tops of the peaks; it clips them off.
>
> If a light on the amplifier is telling you that it is clipping the you
> should turn it down until the light goes off. If this isn't loud enough
> then you should consider getting a more powerful amplifier. A clipping
> amplifier probably will not damage the speaker, especially if it is not
even
> at a level that you consider loud enough. Really, the only was that you
are
> likely to damage a subwoofer is to drive it too loud and either damage the
> voice coil by over heating it or by causing the woofer to move in and out
> too far, again with too much power. I have actually seen a melted voice
> coil so I know that it can happen.
>
> I am a bit concerned that you say that you are not using a crossover.
This
> is not an optional device. I'm not really very familiar with musical
> instrument equipment but if there is not a crossover built into the woofer
> then I would suggest not using it until you have one. Woofers are rugged
> and not as susceptible to being damaged by too high of a frequency as a
> tweeter is to being driven by too low of one but it sill is not a good
idea.
>
>




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sk8erteck

My problem isn's so much that its not loud enough, but that it sounds like
crap when its not clipping.

When it is clipping, it sounds fine.


"Lucy Explainin" <burp@blop.com> wrote in message
news:gsTVb.1728$Y%6.307622@wards.force9.net...
>
> "citronzx" <dillonbaca@earthlink.net> wrote in message
> news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...
> "A clipping amplifier probably will not damage the speaker, especially if
it
> is not even at a level that you consider loud enough".
>
> Not.
>
> Clipping involves (as you describe) a squaring off of the wave, or a
leading
> positive and negative DC edge. This WILL cause damage to a loudspeaker in
> the form of damage to the voicecoil - and it won't take long to manifest
> itself. For this very reason it is SAFER to overdrive a small loudspeaker
> with a big amp and keeping the signal clean and non clipped.
>
> Those BehMINGER amps are not really man enough and Ive found them quite
fun
> run side by side with the likes of Matrix and Crown. "I can't hear it"
being
> the common comment. So don't trust the rated output. Experience says that
if
> its clipping and it does not sound loud enough then it's just not man
> enough.
>
>




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citronzx

"sk8erteck" <sk8erteck@SPAMNOhotmail.com> wrote in message
news:40283127$1_3@corp.newsgroups.com...
> My problem isn's so much that its not loud enough, but that it sounds like
> crap when its not clipping.
>
> When it is clipping, it sounds fine.
>
>

You are right, that does not make any sense! Perhaps there is a protection
circuit in the amp that is somehow creating a pleasant effect.




> "Lucy Explainin" <burp@blop.com> wrote in message
> news:gsTVb.1728$Y%6.307622@wards.force9.net...
> >
> > "citronzx" <dillonbaca@earthlink.net> wrote in message
> > news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...
> > "A clipping amplifier probably will not damage the speaker, especially
if
> it
> > is not even at a level that you consider loud enough".
> >
> > Not.
> >
> > Clipping involves (as you describe) a squaring off of the wave, or a
> leading
> > positive and negative DC edge. This WILL cause damage to a loudspeaker
in
> > the form of damage to the voicecoil - and it won't take long to manifest
> > itself. For this very reason it is SAFER to overdrive a small
loudspeaker
> > with a big amp and keeping the signal clean and non clipped.
> >
> > Those BehMINGER amps are not really man enough and Ive found them quite
> fun
> > run side by side with the likes of Matrix and Crown. "I can't hear it"
> being
> > the common comment. So don't trust the rated output. Experience says
that
> if
> > its clipping and it does not sound loud enough then it's just not man
> > enough.
> >
> >
>
>
>
>
> -----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
> http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
> -----== Over 100,000 Newsgroups - 19 Different Servers! =-----

citronzx

"Lucy Explainin" <burp@blop.com> wrote in message
news:gsTVb.1728$Y%6.307622@wards.force9.net...
>
> "citronzx" <dillonbaca@earthlink.net> wrote in message
> news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...
> "A clipping amplifier probably will not damage the speaker, especially if
it
> is not even at a level that you consider loud enough".
>
> Not.
>
> Clipping involves (as you describe) a squaring off of the wave, or a
leading
> positive and negative DC edge. This WILL cause damage to a loudspeaker in
> the form of damage to the voicecoil - and it won't take long to manifest
> itself. For this very reason it is SAFER to overdrive a small loudspeaker
> with a big amp and keeping the signal clean and non clipped.
>
I'm not sure why you think that a square wave will do damage to a speaker
but you are wrong. If you have a signal generator try playing a square wave
into a speaker for as long as you like and you will find that it causes no
damage. Think about it, what you are saying is that a coil of wire will be
damaged by an AC signal if the signal varies in a particular way. This is
silly of course as long as the power level is resonable for the speaker.
Oh, and I would like to see you graph a signal where a DC signal has any
sort of "edge." Sorry brother but you seem confused.

> Those BehMINGER amps are not really man enough and Ive found them quite
fun
> run side by side with the likes of Matrix and Crown. "I can't hear it"
being
> the common comment. So don't trust the rated output. Experience says that
if
> its clipping and it does not sound loud enough then it's just not man
> enough.
>
>

Arny Krueger

"Lucy Explainin" <burp@blop.com> wrote in message
news:gsTVb.1728$Y%6.307622@wards.force9.net

> "citronzx" <dillonbaca@earthlink.net> wrote in message
> news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...

> "A clipping amplifier probably will not damage the speaker,
> especially if it is not even at a level that you consider loud
> enough".

> Not.

Yep.

> Clipping involves (as you describe) a squaring off of the wave, or a
> leading positive and negative DC edge.

You're talking trash. Seriously. A DC signal by definition can't have an
edge. It holds a steady value, again by definition.

> This WILL cause damage to a
> loudspeaker in the form of damage to the voicecoil - and it won't
> take long to manifest itself.

The voice coils of modern speakers are typically damaged by overheating.
Overheating is caused by the application of too much power. Now, it is true
that a square wave of a given maximum amplitude has more energy or if you
will, heat in it than an equivalent sine wave. However, if you have a music
signal that is squared off so it looks like a square wave, its generally
pretty unlistenable. I

>For this very reason it is SAFER to
> overdrive a small loudspeaker with a big amp and keeping the signal
> clean and non clipped.

Wrong again. The big amp has, surprise surprise, more power. More power can
overheat a voice coil hotter and faster than less power.

> Those BehMINGER amps are not really man enough and Vie found them
> quite fun run side by side with the likes of Matrix and Crown.

So are you saying that you did a level-matched, time-synched,
bias-controlled comparison of them?

> "I can't hear it" being the common comment. So don't trust the rated
> output. Experience says that if its clipping and it does not sound
> loud enough then it's just not man enough.

Or woman enough, depending on your preferences and perceptions...

Experience shows that clipping makes music sound louder.

megabite

Behringer are not especially rugged, high end, electronics. They will do the
assigned job. I suspect you'll need an external "Active" crossover inline,
just before the amp. That way, you will be able to "Cut" anything above the
desired selected hertz you want to amplify and play perhaps 30 hz.- 300hz.
depending on your woofers rating. I think your Woofer is trying to play the
mid and upper freq's and causing the clip and distortion your talking about.
In spite of any crossover that's "Passive" and internal. Are you inputing
the signal at the subs LFE? (Low Freq. Extension, RCA connector, usually
black or white.)
"sk8erteck" <sk8erteck@SPAMNOhotmail.com> wrote in message
news:4028303a_3@corp.newsgroups.com...
> I know its clipping based on the clipping light. I'm familar with what you
> said, but it sounds better when its clipping versus not clipping in higher
> powered mode(bridged mono) at the same sound levels. That doesn't make
sense
> to me, espesically when i came close to blowing the speaker(warning light
on
> the speaker came full on) in bridged mode. The output was no louder than
> when it is clipping.
>
> I know a crossover is needed, I had one ordered as soon as I got the gig.
> There is one built into the woofer, but im thinking that i might get more
> power out of the amp with a crossover, since it doesnt have to amplify the
> highs + mids. That and it will give me more protection for the Peaveys, a
> guest DJ already blew one. (voice coil burnt) We thought that the other
one
> was blown, but when we went up to look at it, it must have been hit by a
> basketball or something because the front grill was bent into the cone.
> Pulled the grill off and it sounded fine.
>
>
> "citronzx" <dillonbaca@earthlink.net> wrote in message
> news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...
>
> > Could you explain how you have determined that the amplifier is
clipping?
> > Clipping is a form of distortion. It happens when an amplifier stage is
> > driven up to and beyond the supply voltage (or current if a current
> > amplifier). Imagine that you are feeding an amplifier sine wave and
> > watching the output on an oscilloscope. Well, if all is well you see a
> sine
> > wave of larger amplitude on the scope. If the amplifier is clipping the
> > tops of the waves will be flattened off because the amplifier cannot
> supply
> > enough power to form the tops of the peaks; it clips them off.
> >
> > If a light on the amplifier is telling you that it is clipping the you
> > should turn it down until the light goes off. If this isn't loud enough
> > then you should consider getting a more powerful amplifier. A clipping
> > amplifier probably will not damage the speaker, especially if it is not
> even
> > at a level that you consider loud enough. Really, the only was that you
> are
> > likely to damage a subwoofer is to drive it too loud and either damage
the
> > voice coil by over heating it or by causing the woofer to move in and
out
> > too far, again with too much power. I have actually seen a melted voice
> > coil so I know that it can happen.
> >
> > I am a bit concerned that you say that you are not using a crossover.
> This
> > is not an optional device. I'm not really very familiar with musical
> > instrument equipment but if there is not a crossover built into the
woofer
> > then I would suggest not using it until you have one. Woofers are
rugged
> > and not as susceptible to being damaged by too high of a frequency as a
> > tweeter is to being driven by too low of one but it sill is not a good
> idea.
> >
> >
>
>
>
>
> -----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
> http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
> -----== Over 100,000 Newsgroups - 19 Different Servers! =-----

gwhite

Lucy Explainin wrote:
>
> "citronzx" <dillonbaca@earthlink.net> wrote in message
> news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...
> "A clipping amplifier probably will not damage the speaker, especially if it
> is not even at a level that you consider loud enough".
>
> Not.
>
> Clipping involves (as you describe) a squaring off of the wave, or a leading
> positive and negative DC edge. This WILL cause damage to a loudspeaker in
> the form of damage to the voicecoil - and it won't take long to manifest
> itself. For this very reason it is SAFER to overdrive a small loudspeaker
> with a big amp and keeping the signal clean and non clipped.


Oh dear.

Lucy Explainin

"citronzx" <dillonbaca@earthlink.net> wrote in message
news:FCXVb.18098$F23.16179@newsread2.news.pas.eart hlink.net...
"I'm not sure why you think that a square wave will do damage to a speaker
> but you are wrong."

If you say so - (the square peak of a clipped signal being a DC component
running on an essentially AC voice coil.)

But hey - you know best - they just like to add clip lights to amplifiers
for decoration :-)

citronzx

"Lucy Explainin" <burp@blop.com> wrote in message
news:cc%Vb.1752$h44.343529@stones.force9.net...
>
> "citronzx" <dillonbaca@earthlink.net> wrote in message
> news:FCXVb.18098$F23.16179@newsread2.news.pas.eart hlink.net...
> "I'm not sure why you think that a square wave will do damage to a speaker
> > but you are wrong."
>
> If you say so - (the square peak of a clipped signal being a DC component
> running on an essentially AC voice coil.)
>
> But hey - you know best - they just like to add clip lights to amplifiers
> for decoration :-)
>
>

Look, you don't have to take my word for it, read the other replies too.

Ulrich

"Lucy Explainin" <burp@blop.com> wrote in message
news:gsTVb.1728$Y%6.307622@wards.force9.net...
>
> "citronzx" <dillonbaca@earthlink.net> wrote in message
> news:nIEVb.17065$F23.6441@newsread2.news.pas.earth link.net...
> "A clipping amplifier probably will not damage the speaker, especially if
it
> is not even at a level that you consider loud enough".
>
> Not.
>
> Clipping involves (as you describe) a squaring off of the wave, or a
leading
> positive and negative DC edge. This WILL cause damage to a loudspeaker in
> the form of damage to the voicecoil - and it won't take long to manifest
> itself. For this very reason it is SAFER to overdrive a small loudspeaker
> with a big amp and keeping the signal clean and non clipped.

I do not concur. Clipping isn't bad for voice coils. Being over driven is
bad for voice coils. Tweeters oftten fry, in passive x-over systems, when
clipping is happening. But, it's not the clipping that's doing the damage.
It's simply that the bass clips first, so that excessive gain cranking leads
only to an increase in wattage to the tweeters.

In an active crossed system, lightly clipping the sub amps is inaudible, and
perfectly OK; if you are not, as a result, overdriving your subs.

Ulrich DoD#732
www.dj-ulrich.com
adelphia email addy is never checked, please use URL above.

Lucy Explainin

"citronzx" <dillonbaca@earthlink.net> wrote in message
newsJ%Vb.18351$F23.185@newsread2.news.pas.earthl ink.net...

hell I must have been taught wrong all those years ago.

Ben

"sk8erteck" <sk8erteck@SPAMNOhotmail.com> wrote in message news:<4026ff0f$1_3@corp.newsgroups.com>...
> (this might be a repost, it never showed up on my ISP's server)
>
> Alright i know that clipping is bad and such, but my subwoofer amp is
> constantly clipping and not distorting at all. It isn't even enough to
> trigger the 'warning' light on the woofer. When I put the amp in
> bridged mode and turn the gain down, the amp doesn't clip but i get
> distortion and the warning light on the woofer turns on. The only way
> to reduce this is to turn the gain way down, to levels that are not
> anywhere near enough or near where it was before the bridge. I've been
> running it unbridged with the clipping for about 2 weeks, is this bad?
> Why is it clipping but sounding fine? Why does it not sound fine in
> bridge mode? Am i damaging the woofer/amp?
>
> Here's what i am working withnot great but it was provided with the gig)
> B-52 Band-Pass Subwooofer rated 550 watts
> Behringer EP1500, rated 260watts at 8ohms in stereo mode, 800 watts in
> bridged mono
>
> Highs + Mids are on another EP1500 hooked up to Peaveys, but that setup
> seems to be working fine. As of now there is no crossover, I have the
> subwooferamp running off of the booth output of my mixer. A behringer
> crossover(i cant remember the model off the top of my head) has been ordered
> and should be in this week.
>
> I'd estimate that the woofer is pushing 250+ watts in stereo mode, but
> only about 100 in bridged mono without distorting. Since it is rated
> 550, how can I get more out of it?
>
> thanks in advance

Just to check, you have just ONE sub, right?

First of all as everyone else said you need an active crossover ASAP.

Ok you have two problems.. the first is the question of whether it is
ok to run it on just one channel of the amp with the amp clip light
blinking. Answer is "it depends". If it is just blinking briefly on
peaks and sounds ok then you are probably safe. If you have a really
good amp then you can push it pretty hard, the clip lights are just a
warning and you have a little bit more room.. like my QSC amp, which
is conservatively rated.. I can run it with clip lights blinking for
hours and there's no audible distortion or overheating problem... on
the other hand there is the Behringer which a cheaper amp made to LOOK
a lot like a QSC... I would not push it too hard because especially
running subs, by the time you hear it sounding bad it will be too
late. I would save this setting for the peak of the evening and not
run it that way all night. In any case you should have the limiter
feature of the amp turned on, it will help protect you from blowing
anything. The other thing you should do is, when no-one is around,
run just the sub alone (no full-ranges) on a track with clean bass,
and then bring the level up slowly, until you can hear it start to
strain, if you bring it up and down slowly you will hear where the amp
starts having a problem.. back off from there until it definitely
sounds good again. Now look at what the peak lights are doing. Don't
let them blink more than that ever. Use the lights as your guide as
to how high you can go not just the knob positions since there are so
many ways to change the level on the mixer...

Also make sure that when you are running with just one channel of the
amp that the other channel input is turned all the way down.

Ok, now your bridge mode problems. What I hear you saying is that
when you are running the amp in bridge mode, you are not getting a
clip light on the amp but getting distortion and a warning on the sub.
So far this sounds right, since with the amp in bridge mode it has
more than enough power to blow the sub if you set the level too high.

But then, if you back the levels down to a point -before- you get
distortion or a warning light on the sub, you don't get as much
undistorted bass as you did running unbridged??? That tells me you
have one of two problems:

1) One channel of the amp is partly or totally blown. It works right
in stereo mode because you happen to be using the good channel.

Or more likely:

2) You don't have the amp hooked up right for bridge mode and you are
lucky you haven't blown anything. I looked at the manual for this amp
(it is on the Behringer web site) and it shows on the back first of
all the speaker connections.. If you have bare wires coming from your
sub then it's easy enough, the two sub wires are connected to the two
middle speaker binding posts (red posts) nothing is connected to the
black posts. That is the connection for bridge mode ONLY. If you are
using a speakon connector to plug the sub into the amp then one wire
in the speakon connector needs to be moved to a different pin (look at
the back of the amp, it tells you), THEN plug the connector into
output #1. If you have't done that it's not going to work correctly.
Also according to the manual, use only input #1, turn down the level
on input #2 and turn off the filter and limited switches for input #2.
The limiter switch should be on for input #1. This also means that
you can only take one channel from your booth output, either left or
right, not both. It doesn't matter so much for now since bass is
usually about the same in both channels.

Once you have this all checked and it's 100% right, then start with
your booth output at no more than 50% and amp input #1 levels at 0,
bring it up slow. If you cannot get as much bass (without distortion
or warning light on the sub) as you did before you bridged it.. then
the amp is screwed up somehow.

Let us know what happens. Good luck.

-Ben