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Run Subs in Mono or Stereo

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Mafia

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Aug 29, 2000, 3:00:00 AM8/29/00
to
hey what are you people's opinion on running subs in mono or stereo? what
are the plus and minus of each mode?? the system i will be using is a combi
or eaw kf300s and sb250s using the mx300i processor. so which mode is better
and why?
btw, if i am to EQ the subs at the GEQ (white instruments) how do i get
about it to get the best results. no boom but bass that impacts the chest!!

Thanks Zhao Li

any Singaporeans here???

mikeof...@hotmail.com

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Aug 29, 2000, 3:00:00 AM8/29/00
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In article <8og521$9s4$1...@coco.singnet.com.sg>,

If you ran subs in stereo, it would take two amps, or at least a stereo
amp. This could be a problem if you don't have the money, but
furthermore, subs are not usually ran in stereo, because the
instruments that are usually in the subs (kick, bass) are usually
panned to the center.


Sent via Deja.com http://www.deja.com/
Before you buy.

Phildo

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Aug 29, 2000, 3:00:00 AM8/29/00
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"Mafia" <too...@singnet.com.sg> wrote in message
news:8og521$9s4$1...@coco.singnet.com.sg...

> hey what are you people's opinion on running subs in mono or stereo? what
> are the plus and minus of each mode?? the system i will be using is a
combi
> or eaw kf300s and sb250s using the mx300i processor. so which mode is
better
> and why?

It all depends where they are crossed but I always run mine in mono. Once
you get to the lower frequencies they are omnidirectional anyway so running
them in stereo has no advantages.

> btw, if i am to EQ the subs at the GEQ (white instruments) how do i get
> about it to get the best results. no boom but bass that impacts the
chest!!

Buy a dbx120DS.

Phildo


Mafia

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Aug 29, 2000, 3:00:00 AM8/29/00
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if i am not wrong, it should be crossing over at about 80 Hz. there are a
few different models of the dbx120, what's the diff btw them???

"Phildo" <LAMS...@pacbell.removethisbit.net> wrote in message
news:967556307.3938.0...@news.demon.co.uk...

R.McTigue

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Aug 29, 2000, 3:00:00 AM8/29/00
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I do multi stereo so I can "wrap" the subs around the stage as well as do a
left to right delay for a thick effect. Mono works well also, it just
depends on what you are trying to do.

Mafia <too...@singnet.com.sg> wrote in message
news:8og521$9s4$1...@coco.singnet.com.sg...
> hey what are you people's opinion on running subs in mono or stereo? what
> are the plus and minus of each mode?? the system i will be using is a
combi
> or eaw kf300s and sb250s using the mx300i processor. so which mode is
better
> and why?
> btw, if i am to EQ the subs at the GEQ (white instruments) how do i get
> about it to get the best results. no boom but bass that impacts the
chest!!
>

Mike Borkhuis

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Aug 29, 2000, 3:00:00 AM8/29/00
to
> hey what are you people's opinion on running subs in mono or stereo?
> what are the plus and minus of each mode??

Personally, I run my systems with the subs in mono.... For the mains,
I'll switch between stereo and mono depending on the venue.

> btw, if i am to EQ the subs at the GEQ (white instruments) how do i get
> about it to get the best results. no boom but bass that impacts the chest!!

My experience has been the EQing hasn't been all that effective for what
you're looking for.... Course, it depends on the program material at hand.

Mike Borkhuis
Worship Technology

Phildo

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Aug 29, 2000, 3:00:00 AM8/29/00
to

"Mafia" <too...@singnet.com.sg> wrote in message
news:8ogh31$b8r$1...@coco.singnet.com.sg...

> if i am not wrong, it should be crossing over at about 80 Hz.

Then run them in Mono. No point at all in running them stereo.

>there are a
> few different models of the dbx120, what's the diff btw them???

That's why I said the 120DS as it's the only model worth having. Only
problem is they stopped making them years ago.

The Behringer Ultrabnass isn't bad if you can't get hold of a 120DS.

Phildo

Denny Conn

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Aug 29, 2000, 3:00:00 AM8/29/00
to
"R.McTigue" wrote:

> I do multi stereo so I can "wrap" the subs around the stage as well as do a
> left to right delay for a thick effect. Mono works well also, it just
> depends on what you are trying to do.

So you're saying that you delay one side of subs relative to the other? Never
heard of it, but sounds interesting. I assume you just run a few milliseconds
of delay?? And does the size of the room make any difference in when you do
this or the amount of delay??

-------->Denny

Key Audio (Kenneth Kareta)

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Aug 29, 2000, 3:00:00 AM8/29/00
to
> "R.McTigue" wrote:
>
> > I do multi stereo so I can "wrap" the subs around the stage as well as do a
> > left to right delay for a thick effect.

Interesting .. have to hear it.
May I assume you do this is just for phase correction?

I'd seen other people delay the outer few subs, in a 200 degree array stack
before.
(the extra 20 degrees added by the %&#@# promoter to
"catch the ear of the people walking in")
--
Ken Kareta, Owns,.
Key Audio Services

Bob Quintal

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Aug 29, 2000, 3:00:00 AM8/29/00
to
mikeof...@hotmail.com wrote:
> 222 26267 <8ogeui$70o$1...@nnrp1.deja.com> article retrieved - body follows

> In article <8og521$9s4$1...@coco.singnet.com.sg>,
> "Mafia" <too...@singnet.com.sg> wrote:
> > hey what are you people's opinion on running subs in mono or stereo?
> what
> > are the plus and minus of each mode?? the system i will be using is a
> combi
> > or eaw kf300s and sb250s using the mx300i processor. so which mode is
> better
> > and why?
> > btw, if i am to EQ the subs at the GEQ (white instruments) how do i
> get
> > about it to get the best results. no boom but bass that impacts the
> chest!!
> >
> > Thanks Zhao Li
> >
> > any Singaporeans here???
>
> If you ran subs in stereo, it would take two amps, or at least a stereo
> amp. This could be a problem if you don't have the money, but
> furthermore, subs are not usually ran in stereo, because the
> instruments that are usually in the subs (kick, bass) are usually
> panned to the center.
>
I also always run subs mono, but because I drive them from a postfade
AUX send out of the board. This gives me great control, I can dial in
extra bottom on only the instruments I want.

Xstudioguy

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Aug 29, 2000, 3:00:00 AM8/29/00
to
There actually is a reason to run them in stereo. I ALMOST alwoays run my
subs in mono, but I found that if I am doing sound for any type of
industrial band or other band that is either keyboard heavy, or uses a drum
machine, then you can actually achieve stereo effects at far lower
frequencies than most subs are crossed over at. Plus, with the growing
number of bass effects available, some bass players are using stereo
effects. As well as the bands that use two physical kick drums. Even these
I will pan center, unless I know that a song uses both drums nearly equally.
Sorry for the novel, just wanted to give you an example of the use of stereo
LOW end, just incase you fall into one of those catagories. :)

"Phildo" <LAMS...@pacbell.removethisbit.net> wrote in message
news:967556307.3938.0...@news.demon.co.uk...
>
> "Mafia" <too...@singnet.com.sg> wrote in message
> news:8og521$9s4$1...@coco.singnet.com.sg...

> > hey what are you people's opinion on running subs in mono or stereo?
what
> > are the plus and minus of each mode?? the system i will be using is a
> combi
> > or eaw kf300s and sb250s using the mx300i processor. so which mode is
> better
> > and why?
>
> It all depends where they are crossed but I always run mine in mono. Once
> you get to the lower frequencies they are omnidirectional anyway so
running
> them in stereo has no advantages.
>
> > btw, if i am to EQ the subs at the GEQ (white instruments) how do i get
> > about it to get the best results. no boom but bass that impacts the
> chest!!
>
> Buy a dbx120DS.
>
> Phildo
>
>
>


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Arkady

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Aug 29, 2000, 3:00:00 AM8/29/00
to
On Tue, 29 Aug 2000, Xstudioguy wrote:

->There actually is a reason to run them in stereo. I ALMOST alwoays run my
->subs in mono, but I found that if I am doing sound for any type of
->industrial band or other band that is either keyboard heavy, or uses a drum
->machine, then you can actually achieve stereo effects at far lower
->frequencies than most subs are crossed over at. Plus, with the growing
->number of bass effects available, some bass players are using stereo
->effects. As well as the bands that use two physical kick drums. Even these
->I will pan center, unless I know that a song uses both drums nearly equally.
->Sorry for the novel, just wanted to give you an example of the use of stereo
->LOW end, just incase you fall into one of those catagories. :)


Speaking for the perspective of a front man for an industrial/techno act I
can say that with the system properly EQed and crossed over there is no
need to run the subs in stereo. I Use alot of stereo effects with my keys
and with the samples etc and I have found that the mains project a great
stereo immage and because the sub bass is so omni-directional anyway, you
really don't lose much if any of that stereo image.

To give you an example, I have a break on one of my songs that uses a
Roland TB-303 bass line that randomly bounces back and forth from hard
stage left to hard stage right in 16th notes at about 138BPM. with my subs
running mono and my mains in stereo, the effect is nothing less that very
impressive. You a 16th note bass thump in your chest while the upper
end of the sound seems to swirl around you.

There again too, I had planned when I was composing for the fact that my
subs would be running mono.

Jason


mri...@my-deja.com

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Aug 29, 2000, 10:51:08 PM8/29/00
to
Whatever is most convenient. IME, it really makes no difference to the
sound. I run mine in stereo because I have one of those super-duper,
way-clever, big-time stereo crossovers (meaning, I got no real choice).
If I had a different sort of crossover setup, I'd run them in mono.

In article <8og521$9s4$1...@coco.singnet.com.sg>,
"Mafia" <too...@singnet.com.sg> wrote:

> hey what are you people's opinion on running subs in mono or stereo?
what
> are the plus and minus of each mode?? the system i will be using is a
combi
> or eaw kf300s and sb250s using the mx300i processor. so which mode is
better
> and why?

> btw, if i am to EQ the subs at the GEQ (white instruments) how do i
get
> about it to get the best results. no boom but bass that impacts the
chest!!
>

> Thanks Zhao Li
>
> any Singaporeans here???
>
>

--
Michael Riehle http://www.mriehle.com
http://www.allnightmusic.com
#include <std_disclaimer.h>

Mike Borkhuis

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Aug 29, 2000, 11:29:59 PM8/29/00
to
> Whatever is most convenient. IME, it really makes no difference to the
> sound. I run mine in stereo because I have one of those super-duper,
> way-clever, big-time stereo crossovers (meaning, I got no real choice).
> If I had a different sort of crossover setup, I'd run them in mono.

But, but, you've always got a choice... A lot of crossovers have a sub
mono switch. And it they don't you could just parrallel the inputs to the
amp.

Mike Borkhuis
Worship Technology

Mike Borkhuis

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Aug 30, 2000, 3:00:00 AM8/30/00
to
> There actually is a reason to run them in stereo. I ALMOST alwoays run my
> subs in mono, but I found that if I am doing sound for any type of
> industrial band or other band that is either keyboard heavy, or uses a drum
> machine, then you can actually achieve stereo effects at far lower
> frequencies than most subs are crossed over at. Plus, with the growing
> number of bass effects available, some bass players are using stereo
> effects.

All well and good... But, if you're not taking a stereo feed from the
bass or keys, it's a moot point. Either way though, the bottom end will have
much more impact when you hit both subs together (mono) then alternating
(stereo).

Mike Borkhuis
Worship Technology

Mafia

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Aug 30, 2000, 3:00:00 AM8/30/00
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thanks for all the suggestions!!!


"Mafia" <too...@singnet.com.sg> wrote in message
news:8og521$9s4$1...@coco.singnet.com.sg...

Phildo

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Aug 30, 2000, 3:00:00 AM8/30/00
to

"Xstudioguy" <bo...@cache.net> wrote in message
news:39ac480c$1...@corp.newsfeeds.com...

> There actually is a reason to run them in stereo. I ALMOST alwoays run my
> subs in mono, but I found that if I am doing sound for any type of
> industrial band or other band that is either keyboard heavy, or uses a
drum
> machine, then you can actually achieve stereo effects at far lower
> frequencies than most subs are crossed over at. Plus, with the growing
> number of bass effects available, some bass players are using stereo
> effects.

Doing it that way merely cuts in half the power available to you in the low
end. Since most club systems are lacking in low end I always run in mono as
the effect of running subs in stereo is negligible at best and get the best
available power from the system.

Then again that has a lot to do with the way I mix using the low end to give
the impression of power/volume and being able to keep the overall volume
level to the point where it won't damage hearing.

Phildo

Juergen Volkmann

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Aug 30, 2000, 8:50:59 PM8/30/00
to
Hi "Mike Borkhuis" <bork...@rochester.rr.com> ,you wrote:


> But, but, you've always got a choice... A lot of crossovers have a sub
>mono switch. And it they don't you could just parrallel the inputs to the
>amp.

Yes, same with my HK-Audio controllers. But...

In bigger venues I always place one (or more) amprack including
controller one each side of the stage and feeding them with the left &
right signal, so there is no chance to get them in mono. (The
controllers of one side are of course all mono'ed)

I'm always thinking about using only one controller for the complete
FOH rig and this would be the only chance to mono my subs, but I never
did because of a feeling of more safety.

Should I really try just one controller?

Bye for now,
Juergen
--
CU...
Too old to rock'n'roll, too young to lie
_Fido_ no longer available :-(

Mike Borkhuis

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Sep 1, 2000, 12:43:10 AM9/1/00
to
> In bigger venues I always place one (or more) amprack including
> controller one each side of the stage and feeding them with the left &
> right signal, so there is no chance to get them in mono. (The
> controllers of one side are of course all mono'ed)

Gotcha...

> I'm always thinking about using only one controller for the complete
> FOH rig and this would be the only chance to mono my subs, but I never
> did because of a feeling of more safety.
>
> Should I really try just one controller?

Running one controller would be one solution... Course, it'd require
crossing all bands over to the other rack. A simpler solution would be to run
a single cable between the racks, tying the just the sub outputs together.
So, when one side hits, so does the other.
Another option would be to run the subs separate and feed it either off
the mono out (stereo to the mains) OR a post fader aux. This would require a
low pass filter/crossover though....

Mike Borkhuis
Worship Technology


gz

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Sep 1, 2000, 12:19:20 PM9/1/00
to
"Phildo" <LAMS...@pacbell.removethisbit.net> wrote in message
news:967638956.27073.0...@news.demon.co.uk...

Ah - what a concept! I think every FOH engineer should take note.
Same goes for movies - they are louder than a lot of rock concerts.

gz

>
> Phildo
>


R.McTigue

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Sep 1, 2000, 1:39:17 PM9/1/00
to
Also setting up subs in a left stereo allows "friendly comb filtering" so
you can keep the subs from summing in the center and get better overall sub
coverage, i.e. no sub hump in the center of the room and not enough sub on
far left and right of room.


R.McTigue

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Sep 1, 2000, 1:46:54 PM9/1/00
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Sorry... not left stereo, but stereo
"R.McTigue" <rob...@bellsouth.net> wrote in message
news:ASRr5.5604$pJ.8...@news2.atl...

Key Audio (Kenneth Kareta)

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Sep 1, 2000, 6:56:07 PM9/1/00
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"R.McTigue" wrote:

> i.e. no sub hump in the center of the room and not enough sub on
> > far left and right of room.

Isn't that what EAW once called "Steering"?

Shaun

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Sep 1, 2000, 7:09:48 PM9/1/00
to
"Key Audio (Kenneth Kareta)" wrote:

> Isn't that what EAW once called "Steering"?

It works. I've done a bunch of tests, and found that you can bend audio
all over the place, using judicious delays and gain shading. Even
easier and more directional when using tuned dipolar arrays.
--
Shaun K. Wexler,
Hellsgate Sound
http://www.hellsgate-sound.com

Shaun

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Sep 1, 2000, 9:37:27 PM9/1/00
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Mafia wrote:

> so now what do i do?? mono or stereo, yes, the coverage of the room is
> rather fan like .....

If you have enough amps and processing to run subs in stereo, by all means do
so. Most instruments which require the impact of subs (kick & bass) are
mono, and will drive both subs equally if panned center. When discussing a
small system such as yours, it is preferred by some to utilize all available
power in the sub system by running mono, but it is only beneficial for
instruments with lots of sub-bass info which are panned substantially to one
side or the other.

It all boils down to: "If you've got it, flaunt it."

SPARKY

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Sep 1, 2000, 9:53:52 PM9/1/00
to
Mike Borkhuis wrote:
[snip]

> > I'm always thinking about using only one controller for the complete
> > FOH rig and this would be the only chance to mono my subs, but I never
> > did because of a feeling of more safety.
> >
> > Should I really try just one controller?
>
> Running one controller would be one solution... Course, it'd require
> crossing all bands over to the other rack.

I don't see what the difference is between having a cross-stage snake
feeding the inputs of the second processor, and having a cross-stage snake
to feed the inputs of the other amps using the first processor as the
drive. Isn't it the same amount of wire?

> A simpler solution would be to run a single [XLR] cable between the racks,
> tying just the sub outputs [inputs?] together so when one side hits, so does the other.
> Mike Borkhuis
> Worship Technology

This seems to be the easiest way to test out the mone sub theory.

--
Joel Farris "SPARKY"
Plus3dB Productions, LLC
*Sound Reinforcement*
*Technical Direction*
*Video Production*


Mike Borkhuis

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Sep 1, 2000, 10:54:17 PM9/1/00
to
> .....When discussing a small system such as yours, it is preferred by
> some to utilize all available power in the sub system by running mono.....

Another reason I'll do mono subs is that I can usually get more power
bridged 4 ohms rather than stereo 8ohm.... At least with the low end rental
systems I've been using. (Mental note, need to buy main speaker/amp setup
SOON)

Mike Borkhuis
Worship Technology

Mike Borkhuis

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Sep 1, 2000, 10:56:51 PM9/1/00
to
> I don't see what the difference is between having a cross-stage snake
> feeding the inputs of the second processor, and having a cross-stage snake
> to feed the inputs of the other amps using the first processor as the
> drive. Isn't it the same amount of wire?

Well, it depends on where the controller is... If it's at FOH, you'll
still need to run 3 (or 4) way stereo to the amps, so there's no difference...
If it's in the amp racks, you only need a single line to feed each rack (right
& left), saving you a little cabling....

Mike Borkhuis
Worship Technology

SPARKY

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Sep 2, 2000, 4:12:48 AM9/2/00
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Shaun wrote:

> It all boils down to: "If you've got it, flaunt it."

And this from a guy with *arc welders* in his amp racks!

Peter Larsen

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Sep 2, 2000, 8:50:31 AM9/2/00
to

Phildo wrote:

> "Mafia" <too...@singnet.com.sg> wrote in message
> news:8og521$9s4$1...@coco.singnet.com.sg...
> > hey what are you people's opinion on running subs in mono or stereo? what
> > are the plus and minus of each mode?? the system i will be using is a
> combi
> > or eaw kf300s and sb250s using the mx300i processor. so which mode is
> better
> > and why?
>
> It all depends where they are crossed but I always run mine in mono. Once
> you get to the lower frequencies they are omnidirectional anyway so running
> them in stereo has no advantages.

The intrinsic problem in running them in stereo is that you would be
using amplifier power to reproduce stuff that would cancel out anyway
but in different ways across the room. Much better to cancel it out
electronically before even entering the amp array, also in terms of
getting consistent sound all over the room.

> > btw, if i am to EQ the subs at the GEQ (white instruments) how do i get
> > about it to get the best results. no boom but bass that impacts the
> > chest!!
>

> Buy a dbx120DS.

Perhaps someone should set up a robot mailer to cc all posts about that
contraption to DBX, they don't seem to have gotten the point yet ...
O;-) ... sometimes the ones that one wants to read usenet just doesn't.
Anyway, allow me to toss in that the subs should be linear as low down
as they do it well, and that they should have a sharp highpass filter to
prevent them from trying to do what they don't do very well. Also good
microphone low range linearity will help.

> Phildo


Kind regards

Peter Larsen

--
******************************************************************
* This posting handcrafted by Peter Larsen, pla...@teliamail.dk *
* My homepage is at: http://w1.1358.telia.com/~u135801844/ *
******************************************************************

Peter Larsen

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Sep 2, 2000, 8:50:28 AM9/2/00
to

Mafia wrote:

> hey what are you people's opinion on running subs in mono or stereo?

Wrong subject header, the options are 1) run subs in mono or 2) run subs
in mono. You could also try to run your subs in mono.

The exception is purists playback of natural stereo recordings in the
home, in which case you should run subs in stereo to get the ambience
right, because out of phase VLF is a vital ingredient in the spatial
experience and it can not be reproduced by subs in mono.

Don't read me as impolite, the above simply is how it is.

> Thanks Zhao Li

Xstudioguy

unread,
Sep 2, 2000, 4:17:22 AM9/2/00
to
I guess there was some confusion with my earlier post. There are obviously
reasons for not running stereo. I was not saying to blindly run them in
stereo. There have been many excellent reasons for running them mono
mentioned here. I merely wanted to point out that are times when stereo
subs can be effective. When I run my subs in stereo, I use a BSS omnidrive
and have way more power and cabinets than necessary to get the sound I need.
So basically, the loss in power efficiency as negligable with my racks and
stacks. As for the cancellation, it doesn't happen. If your subs are
cancelling, my first bet would be to check the polarity across your signal
chain and drivers. Especially the drivers. In this case, even mono subs
would cancel.

Xstudioguy

unread,
Sep 2, 2000, 4:18:39 AM9/2/00
to
Try a "Y" cable so then your signal is at least mono.
"Juergen Volkmann" <sel...@gmx.de> wrote in message
news:8oka5k$un1$10$1...@news.t-online.com...

Robert McTigue

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Sep 2, 2000, 11:30:09 AM9/2/00
to
Inducing the "friendly comb filtering" is a bit different than bending the
subs. If I have done all my sub to mains timing and have a bit of a "hump"
in the center of the room .. THEN I induce the comb filtering. Not all rooms
are the same as we all know, so I have to play with it a bit to get it
right. To induce to comb filtering all I do on my x-over(BSS 366x4) is
reduce sub output to left 1.2db and reduce low output to right 1.2db
(amount of cut is not fixed). I am lucky that I work for a company that felt
it was important to have the right tools to get the job done!
"Key Audio (Kenneth Kareta)" <k...@keyaudio.com> wrote in message
news:39B03407...@keyaudio.com...

André Huisman

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Sep 2, 2000, 12:58:39 PM9/2/00
to
"Peter Larsen" <pl...@get2net.dk> wrote:

> Wrong subject header, the options are 1) run subs in mono or 2) run subs
> in mono. You could also try to run your subs in mono.

Grin (not an evil one, a friendly grin this time).

> The exception is purists playback of natural stereo recordings in the
> home, in which case you should run subs in stereo to get the ambience
> right, because out of phase VLF is a vital ingredient in the spatial
> experience and it can not be reproduced by subs in mono.

Aaah yes, I have often seen this remark! I most often see it written by
"purists" (no suggestions intended) that use Vinyl as a source. They complain
that a mono sub signal below 80Hz degrades the stereo picture. Very very odd.
Why is that? Because Vinyl is as MONO as it gets below some 100Hz or so.

Funny ain't it?

I've used home subs crossed below 80Hz (one single Sub BTW so it was as mono as
it gets ;-) and found no degradation in the stereo picture.

> Don't read me as impolite, the above simply is how it is.

I learned (way back when...) that we don't hear directions below roughly
150-100Hz. The explanation was that it had something to do with the distance
between our ears. Now an elephant can probably hear direction downto 10Hz (and
he probably SHOULD ;-).

Any corrections on the above are (of course) appreciated.

Phildo said that you could mono the subs because the subs are omnidirection.
That might well be (it's awfully dependant on the type of subs; especially it's
effective area of radiation IMO) but to me the REAL reason we can sun subs in
mono (and should wherever possible) is simply because we can't hear where it's
coming from anyway.

Greetings,

--
André Huisman
New Line licht & geluid
hui...@new-line.nl
http://www.new-line.nl
--- pardon my French, I'm Dutch ---


Peter Larsen

unread,
Sep 2, 2000, 9:27:36 PM9/2/00
to
"André Huisman" wrote:


> "Peter Larsen" <pl...@get2net.dk> wrote:

> > The exception is purists playback of natural stereo recordings in the
> > home, in which case you should run subs in stereo to get the ambience
> > right, because out of phase VLF is a vital ingredient in the spatial
> > experience and it can not be reproduced by subs in mono.

> Aaah yes, I have often seen this remark! I most often see it written by
> "purists" (no suggestions intended) that use Vinyl as a source. They complain
> that a mono sub signal below 80Hz degrades the stereo picture. Very very odd.
> Why is that? Because Vinyl is as MONO as it gets below some 100Hz or so.

Perhaps always as when cut by a rock engineer, possibly not always as
when cut by a classical engineer, I never did bother to check generally,
but I have at least one direct cut recording that has out of phase LF on
it, oh - and I think Uncle Meat also has quite a problem with some of
the tracks, I vaguely remember something about Frank Zappa re-doing some
of the bass stuff on it for the digital release.

> Funny ain't it?

> I've used home subs crossed below 80Hz (one single Sub BTW so it was as mono as
> it gets ;-) and found no degradation in the stereo picture.

Well, on what recordings, also I didn't say stereo picture, I said
ambience because it is about ambience and spatial perspective.

> > Don't read me as impolite, the above simply is how it is.
>
> I learned (way back when...) that we don't hear directions below roughly
> 150-100Hz.

True, but we do detect whether there is out of phase LF and out of phase
LF is a characteristic of a real room.

> The explanation was that it had something to do with the distance
> between our ears. Now an elephant can probably hear direction downto 10Hz (and
> he probably SHOULD ;-).
>
> Any corrections on the above are (of course) appreciated.

I think you have been listening for something other than what it is
about. Try to find a recording of Danish Concert Band recorded by
Nielsen and Krogh.

> Phildo said that you could mono the subs because the subs are omnidirection.

Didn't read that, he must have been more tired than I am right now when
he wrote it.

> That might well be (it's awfully dependant on the type of subs; especially it's
> effective area of radiation IMO) but to me the REAL reason we can sun subs in
> mono (and should wherever possible) is simply because we can't hear where it's
> coming from anyway.

Simple amplifier power math does it for me with this, it is a certified
waste of power in a concert situation to reproduce anything that will
cancel out anyway.

Here is the design of a neat little black box I made for analog post
processing, it could come in very handy in many contexts: I bought a
pair of high quality line level transformers once upon a time, just in
case I needed them and because I could get them at a good price.
Occasionally goofing I happened to have a few recordings that had a wee
bit of out of phase LF in them, well - an inductor between the channels
will reduce low end channel separation, so they ended up in a small
black plastic box with one sides windings in series between the
channels, did some experiements to verify not only that it measured
sensibly in terms of loss of channel separation, but also sounded
correctly with the then relevant output impedance of the mixer they were
designed to be used with, one could also simply add a series stereo
potentiometer of a suitable resistance, 1 kOhm comes to mind as
something one is likely to get away with assuming sensible input
impedance, and then make it variable. It is probably heresy, but every
lil' box of tricks should have one, it can make swampy stereo bass a lot
tighter.

> André Huisman

Peter Larsen

unread,
Sep 3, 2000, 1:30:03 PM9/3/00
to

Phildo wrote:
>
> "Peter Larsen" <pl...@get2net.dk> wrote in message
> news:39B1A908...@get2net.dk...

[quoting André]

> > > Phildo said that you could mono the subs because the subs are
> > > omnidirection.
> >
> > Didn't read that, he must have been more tired than I am right now when
> > he wrote it.
> >

> Nope, I still mean it. Not 100% evenly omnidirectional in the same way as
> microphones but they're not exactly long-throw and will move air in all
> directions no matter what you do. Just go backstage at a festival and
> listen. Do you hear any high frequencies or just the lows? The subs fire all
> over the place, not just in the direction they are pointing.

I'm with you this far, but I am short of logic when it comes to seeing
as a valid explanation for "might as well run them mono". It would be
just as valid a reasoning for "might as well run them stereo"!

> Run the subs in mono because the human ear can't
> perceive where the low end is coming from anyway.

This is not entirely correct, yes - I know what the books say, but the
human sense of hearing is very good at determining whether the LF sound
field contains out of phase components, and thereby determing some
faculties of the sound generating body as well as making a good guess at
relative distance.

> Gives you a nice foundation to build the stereo image on.

And the above is the reason why one should run them mono: to ensure that
it sounds closeby!

> Leave the panning to the higher frequencies where the audience will
> actually notice them.

I wholeheartedly agree!

> Phildo

Phildo

unread,
Sep 3, 2000, 4:23:46 PM9/3/00
to

"Peter Larsen" <pl...@get2net.dk> wrote in message
news:39B28A9B...@get2net.dk...

>
> I'm with you this far, but I am short of logic when it comes to seeing
> as a valid explanation for "might as well run them mono". It would be
> just as valid a reasoning for "might as well run them stereo"!

Yeah but should you pan something hard left or hard right you are limiting
the amount of power available to you in the low end. A lot of it has to do
with the way I mix but I need as much low end power as possible so always
run subs in mono. A sound only in the left side only has one set of amps and
subs available to it whereas should you run the subs in mono you have all
the power available all the time to all the sounds.

> > Run the subs in mono because the human ear can't
> > perceive where the low end is coming from anyway.
>
> This is not entirely correct, yes - I know what the books say, but the
> human sense of hearing is very good at determining whether the LF sound
> field contains out of phase components, and thereby determing some
> faculties of the sound generating body as well as making a good guess at
> relative distance.

How many audience members will notice that though?

> > Gives you a nice foundation to build the stereo image on.
>
> And the above is the reason why one should run them mono: to ensure that
> it sounds closeby!

Agreed. Personally I'm just a low frequency junkie and that's why I run them
in mono.

> > Leave the panning to the higher frequencies where the audience will
> > actually notice them.
>
> I wholeheartedly agree!
>

End of subject then :>)

Phildo

Peter Larsen

unread,
Sep 5, 2000, 3:41:13 PM9/5/00
to

"André Huisman" wrote:

> "Peter Larsen" <pl...@get2net.dk> wrote:

> It is not about the distance between our ears? Please tell me what it IS about
> (for I'd like to get rid of some of my misconceptions ;-)

Frankly I am at a loss to explain this. Try to misphase your subs, and
what do you get: unease, a pressing feeling on/in the ears, so it is
detected. It is also very clearly audible if you remove out of phase LF
with the suggested black box.

Juergen Volkmann

unread,
Sep 5, 2000, 5:23:46 PM9/5/00
to
Hi "Miller" <matm...@matmiller.freeserve.co.uk>, you wrote:

>> After this I have to check again with my d&b System, which I only use
>> when working with German radio & television.
>>
>> The HKs are my favourite workhorse ;-)
>
>HK over D&B - are ye fookin mad?

I knew I would getting flamed ;-) <bg>

I currently own
16 HK VT112
16 HK HL118
4 HK VT212
12 HK SM112
8 HK VT110
different amping and controllers
which I use in different sets from club to open air gigs.

From the d&b side my stock is
4 1220 d&b-biamped
6 902 d&b-amped
6 E1 d&b-amped

and yes, I still like the sound of the HK's more than the d&b's, but
of course I only can compare (a/b) my own stock.

The d&b's are too boomy IMHO and it is very hard for me getting the
clean and crisp sound I like with HK. With the HKs eq-ing is much
easier.

Sorry again, but it works for me and 95% of my customers.
The d&bs are reserved for radio & television companies, they always
have them in their riders.

Please don't "flame" again, it's just a question of taste, IMHO :-)

Bye

André Huisman

unread,
Sep 6, 2000, 9:52:08 AM9/6/00
to
"Peter Larsen" <pl...@get2net.dk> wrote:

> > It is not about the distance between our ears? Please tell me what it IS
about
> > (for I'd like to get rid of some of my misconceptions ;-)

> Frankly I am at a loss to explain this. Try to misphase your subs, and
> what do you get: unease, a pressing feeling on/in the ears, so it is
> detected. It is also very clearly audible if you remove out of phase LF
> with the suggested black box.

Aaah, yes, out of phase information. If this happens to me, my ears "collapse"
(and it's actually painfull, be it probably in a psychological manner). However,
with subs I have NOT noticed this (for I've had a few mishaps in the past where
subs were out of phase (thanx Carver; this was before I fixed the Pin-3=hot
flaw)).

So I "pose" that this "unease" is only appararent when the information in
question contains higher frequencies than those found on your average, good
working, sub. Might be that the subs you've investigated this on were either not
as bandwidth restricted as those I use (<100Hz, 4th order) OR that these subs
exhibited quite some harmonic distortion, triggering your ear to the mishap OR
that some strange room phenomena were occuring.

Darn, now I still don't know anything more about this "ear's direction finding
ability".

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