Coupling?

Coupling?

Coupling

What is it?

TO me, it's when the cab rests flat on the floor (or stage) thus
producing a better sound than when the cab is off the floor (casters).

Once in a while a stage is hollow underneath. TO me, in this scenario,
cpuoling is not a good thing because you can increase boominess if the
right frequencies are being matched bvwtweent eh satage and your cab.

SO here I think casters are fine. I've used an Auralex Grammex too adn
I like them although I don't really know if I'm now copiled or
decpopled. My tendency is to think I'm coupled but with a controlled
medium between the cab adn stage.



Anyone?

Re: Coupling?

I think your post is going to stir up a very long thread and morph into
something very different.
Notice how the "Basses that changed history" has morphed into a debate
about who was more famous and wealthy, David Crosby or the Grateful Dead.
LMAO.

SotR

Re: Coupling?

"ZaveyZipper" <das216at_comcast . net > wrote in message
news:8P6dnQLwzMHJVbrVnZ2dnUVZ_uydnZ2d@comcast . com ...
> Coupling
>
> What is it?
>

It's how classy people fuc-

Sorry, I couldn't resist!

Re: Coupling?

The other night I played at The Spice Lounge in Milton Keynes, they have a
small riser stage, which they have just made smaller. We played there about
2 months ago and there was room for my cabinet to be up on the riser but
this time I had to place it on a hard concrete floor.
The difference in sound was really extreme. I remember coming away from the
first gig thinking that my sound was really bad and wishing I had not done
it, this time I realised that I could hear every note crystal clear, no
booming muddy drone under everything like the first time. It was a pleasure
because I could dial in what ever sound I needed for each number.
A lesson that seems to have taken me a while to learn but so glad I did.
I am going to find a rubber base that will disconnect my cab from the stage
in future, any suggestions?
Hotfoot

"Jonathan" <jonathan@kelloggcreek . com NOSPAM> wrote in message
news:g08q2q016ki@enews1.newsguy . com ...
: "ZaveyZipper" <das216at_comcast . net > wrote in message
: news:8P6dnQLwzMHJVbrVnZ2dnUVZ_uydnZ2d@comcast . com ...
: > Coupling
: >
: > What is it?
: >
:
: It's how classy people fuc-
:
: Sorry, I couldn't resist!
:
:

Re: Coupling?

On May 12, 12:32 am, ZaveyZipper <das216at comcast . net > wrote:
> Coupling
>
> What is it?

It's when you have a sonic source (speakers in your bass cab) and it
excites sympathetic vibrations in something else. That "something" can
be a wooden stage floor or it can simply be the surrounding air. In
other words the speaker motions can be more or less effective in
moving (coupling to) the air. Generally the latter is a result of the
proximity of the cab to walls and floor surfaces. For example if you
place your cab in the corner of a room the walls of the room act act
as the extensions of a horn which greatly increases the
"coupling" (efficiency) of the low frequencies from the cabinet to the
air in the room. If you place the cab at the junction of a wall and
the floor you get less, if it's just on the floor, you get still less
and if it is sitting up on a chair it in effect tends not to use those
surfaces for coupling much at all. These effects are different from
vibrating the stage floor which then acts as a sounding board. Both
effects are real.

> TO me, it's when the cab rests flat on the floor (or stage) thus
> producing a better sound than when the cab is off the floor (casters).

Well, "better" is a matter of opinion! It depends on so many things
there can't be a rule. Some people go for the deeper bass of the floor/
wall supported cab. They feel they can dial that in just fine. Others
hate the "boominess" of it and love the clean sound of a cab suspended
in air above the floor a couple of feet! I'm not sure there is a
"right" way to do things. But as a rule if the cab is exciting
something with a very sharp resonance frequency (could be a stage
floor that does this) then the sound will tend to be muddy and boomy.

> Once in a while a stage is hollow underneath. TO me, in this scenario,
> cpuoling is not a good thing because you can increase boominess if the
> right frequencies are being matched bvwtweent eh satage and your cab.

Can be true. But floor and walls matter too. And some cabs just get
boomy if you don't get them away from the flat surfaces.

> SO here I think casters are fine. I've used an Auralex Grammex too adn
> I like them although I don't really know if I'm now copiled or
> decpopled. My tendency is to think I'm coupled but with a controlled
> medium between the cab adn stage.

> Anyone?

Sort of but some people like the cab on a "chair" thing because it
reduces two couplings. One to the stage floor and the other the air
coupling to the floor and walls that give increased low bass. The
beauty of this is that you create a certain amount of independence
from the configuration of the room. The down side is that your low
bottom is rather rolled off a bit and you may need to compensate with
EQ and more power.

In my opinon the biggest problem with castors is they tend to rattle
(sympathetic vibrations from the cab). The biggest problem with no
castors is making dragging the cab in a much bigger pain than wheeling
it in.

Re: Coupling?


"Benj" <bjacoby@iwaynet . net > wrote in message
news:54f37eee-caa1-41fa-b6b9-f2fc9fd81ad2@f36g2000hsa.googlegroups . com ...
> On May 12, 12:32 am, ZaveyZipper <das216at_comcast . net > wrote:
>> Coupling
>>
>> What is it?
>
> It's when you have a sonic source (speakers in your bass cab) and it
> excites sympathetic vibrations in something else. That "something" can
> be a wooden stage floor or it can simply be the surrounding air. In
> other words the speaker motions can be more or less effective in
> moving (coupling to) the air. Generally the latter is a result of the
> proximity of the cab to walls and floor surfaces. For example if you
> place your cab in the corner of a room the walls of the room act act
> as the extensions of a horn which greatly increases the
> "coupling" (efficiency) of the low frequencies from the cabinet to the
> air in the room. If you place the cab at the junction of a wall and
> the floor you get less, if it's just on the floor, you get still less
> and if it is sitting up on a chair it in effect tends not to use those
> surfaces for coupling much at all. These effects are different from
> vibrating the stage floor which then acts as a sounding board. Both
> effects are real.
>
>> TO me, it's when the cab rests flat on the floor (or stage) thus
>> producing a better sound than when the cab is off the floor (casters).
>
> Well, "better" is a matter of opinion! It depends on so many things
> there can't be a rule. Some people go for the deeper bass of the floor/
> wall supported cab. They feel they can dial that in just fine. Others
> hate the "boominess" of it and love the clean sound of a cab suspended
> in air above the floor a couple of feet! I'm not sure there is a
> "right" way to do things. But as a rule if the cab is exciting
> something with a very sharp resonance frequency (could be a stage
> floor that does this) then the sound will tend to be muddy and boomy.
>
>> Once in a while a stage is hollow underneath. TO me, in this scenario,
>> cpuoling is not a good thing because you can increase boominess if the
>> right frequencies are being matched bvwtweent eh satage and your cab.
>
> Can be true. But floor and walls matter too. And some cabs just get
> boomy if you don't get them away from the flat surfaces.
>
>> SO here I think casters are fine. I've used an Auralex Grammex too adn
>> I like them although I don't really know if I'm now copiled or
>> decpopled. My tendency is to think I'm coupled but with a controlled
>> medium between the cab adn stage.
>
>> Anyone?
>
> Sort of but some people like the cab on a "chair" thing because it
> reduces two couplings. One to the stage floor and the other the air
> coupling to the floor and walls that give increased low bass. The
> beauty of this is that you create a certain amount of independence
> from the configuration of the room. The down side is that your low
> bottom is rather rolled off a bit and you may need to compensate with
> EQ and more power.
>
> In my opinon the biggest problem with castors is they tend to rattle
> (sympathetic vibrations from the cab). The biggest problem with no
> castors is making dragging the cab in a much bigger pain than wheeling
> it in.
>

I prefer to leave my cabs on casters whenever possible, mainly to minimize
any coupling effect. This helps me replicate MY tone in just about any
venue. Every stage is different, so the coupling is different as well. To
me, it just makes it more difficult to dial into any given room.
--
Keep Thumpin', Lane...

Ask not what bass can do for you...Ask what YOU can do for bass.
w w w .laneonbass . com | w w w .myspace . com /lanebaldwin
w w w .deeperblues . com | w w w .myspace . com /deeperblues
w w w .basstalkradio . com | w w w .myspace . com /basstalkradio
w w w .eden-electronics . com | w w w .myspace . com /edenelectronics

Re: Coupling?

> In my opinon the biggest problem with castors is they tend to rattle
> (sympathetic vibrations from the cab). The biggest problem with no
> castors is making dragging the cab in a much bigger pain than wheeling
> it in.

"Casters."

Re: Coupling?

> Coupling
>
> What is it?

There's acoustic coupling, which is an effect caused by reflections and
reinforcement of sound waves; and then there's physical coupling of the
vibrating cabinet to the surface that it's sitting on. Neither one is
affected at all by casters.

The height difference caused by adding casters is immaterial in relation
to the wavelengths of bass frequencies. The boundary reinforcement you
get from your cab being on the floor will be unchanged if you add
casters to the cab.

If you're on a wood floor or other surface that can vibrate, the
vibration will be caused primarily by sound waves in the air and
secondarily by vibrations transferred directly from the cabinet. The
vibrations transferred directly by the cabinet will be the same if you
have rubber feet, no feet, or casters. Obviously, the floor vibrations
caused by sound waves will not be affected by casters.

Someone predicted that this will be a long thread -- I agree, this topic
has generated a lot of confused arguments in the past. All you have to
do is try the various configurations in the real world. Makes no
difference at all, as far as "coupling" goes. In most cases,
sympathetically-vibrating surfaces can only do bad things to your sound,
not good. In live-performance situations, where levels are very high,
sympathetic vibrations caused by sound waves will completely overwhelm
any vibrations transferred directly from your cab to the floor, so
isolation pads are a waste of money. In the studio, I'm still skeptical
of their usefulness, but at least there's a greater chance that they
will make a positive difference. There's too much hocus-pocus,
Monster-Cable-style horseshit marketing surrounding things like the
Gramma pads, there's just a little too much emphasis on separating you
from your hard-earned money and not enough on real-world effects. You
take anyone that swears by them, and put them in a double-blind test and
I'll bet you anything they can't find a positive improvement to the
sound, even if they can identify a difference. Remember, a perceptible
difference is a very different thing from an improvement, but the
manufacturers and marketers know that a difference will be perceived as
an improvement 99% of the time.

The most important thing is to place your cab carefully in relation to
walls and the floor, so you can hear yourself best on stage. Boundary
effects on stage give you a false impression that your sound is very
fat, full or boomy in the audience, when in fact, it's not. If you EQ
on stage to compensate for boundary effects, your sound in the audience
will be thin and tinny. By all means, put casters on your cabs, makes
it a hell of a lot easier to load in and out.

As always with topics like this, don't debate in newsgroups, go out and
try it yourself and see.

Re: Coupling?

I experienced a weird example of it back a few previous lifetimes ago.
We were playing in one of those old fashioned band shells - like
they used to have in parks and at the beach for bands to play in. I
was using a Music Man HD-130 bass head and two folded horn cabinets.
It was the same setup I had used for months. That day I blew out a
250 watt Gauss 18" and a 150 watt JBL 15" with a 130 watt amplifier.
The recone shop said both speakers had over-excurded. All I can
remember about it was fighting to get a normal tone. There was no
punch - before they blew out, that is. It was like playing through
the speakers without a cabinet. The band shell must have had a
resonance in the bass register. Somehow the folded horn cabinets
coupled with it in such a way that the drivers saw zero acoustic
impedance at some particular frequency. I finished the gig playing
through the keyboard player's 4-12 cabinet.

jk

ZaveyZipper wrote:
> Coupling
>
> What is it?
>
> TO me, it's when the cab rests flat on the floor (or stage) thus
> producing a better sound than when the cab is off the floor (casters).
>
> Once in a while a stage is hollow underneath. TO me, in this scenario,
> cpuoling is not a good thing because you can increase boominess if the
> right frequencies are being matched bvwtweent eh satage and your cab.
>
> SO here I think casters are fine. I've used an Auralex Grammex too adn
> I like them although I don't really know if I'm now copiled or
> decpopled. My tendency is to think I'm coupled but with a controlled
> medium between the cab adn stage.
>
>
>
> Anyone?