I like my Fender Rumble better when it's decoupled; my Markbass better when it's coupled.
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Coupling Vs. Decoupling
- Thread starter TerribleTim68
- Start date
It really depends o. How resonant the stage is and how big the stage is. I play one place with a relatively small stage that is very resonant - I either put my cabs up on a stand or I put a carpet pad in front of it to try to tame it a bit. Everywhere else I tend to leave it coupled. When I use only 1 cabinet I will still use the stand but that's more to get it closer to my ears than to decouple... I usually use 2 cabs.
hmmm, everything I have is on wheels for easy moving.
In larger venues, I really don't know the difference anyway because my mix is in the stage monitors and side fills, I only hear the amp if I stand right next to it.
Interesting points all around though.
In larger venues, I really don't know the difference anyway because my mix is in the stage monitors and side fills, I only hear the amp if I stand right next to it.
Interesting points all around though.
- If you have coupling problem the you solve it by decoupling.
- If you have decoupling problem you solve it by coupling.
If you're trying to squeeze out extra bass by coupling rethink that speakers move back and forth, not up and down when they vibrate. Cabs don't vibrate up and down into the stage.
Some people naturally regurgitate to "buy" a special acoustic pad because they believe the pseudo science put out by those who make special acoustic pads. I don't know of any cab maker who would say their cabinet would benefit from such pads, unless they also happen to sell the pads.
You can hear major touring bassist who use IEM's like to feel the bass - then they discover buttkicker shakers attached to the stage so they can feel a shake. Problem solved.
Shaking has nothing to do with hearing, in fact nerves in you body go numb from shaking. It's only a short term effect, until your sodium potassium pumps can equal out again.
FOH subs on most club PA actually flood the stage anyhow. Got through FOH with IEM's and you'll feel the shake.
Keep a buttkicker handy, or a pole mount to fix your coupling/decoupling either way.
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The pads can be helpful to decouple the cabinet from an amp sitting on top of it. Especially with preamp tubes that can become microphonic in some designs, and with certain tube construction techniques.
There are also some stages where mechanically isolating or decoupling the cabinet from the stage can reduce the mechanically coupled vibration the the stage deck and any resonant cavities beneath it. Of course it won't do much for purely acoustic coupling (the dominant form of coupling for bass)
There are also some stages where mechanically isolating or decoupling the cabinet from the stage can reduce the mechanically coupled vibration the the stage deck and any resonant cavities beneath it. Of course it won't do much for purely acoustic coupling (the dominant form of coupling for bass)
I think the related terms you are looking for are space loading and boundary effect. Space loading relates to the number of boundaries near the speaker. If the speaker is up in the air away from all boundaries, it is said to be in whole space or free space. If the speaker is on the floor it's said to be half space loaded (+3dB). If it's on the floor and against a wall it's quarter space loaded (+6dB). If it's on the floor in the corner (two walls), it's eight space loaded, (+9dB). Here's a related article: https://www.prosoundtraining.com/site/wp-content/uploads/2012/03/VOL36_DEC08_Boundaries-1.pdf
There is some confusion. Some articles list the gains as 3dB, 6dB and 9dB respectively for half, quarter, and eight space loading, while other articles lists 6dB, 12dB, and 18dB. I will say that the author of the article, Pat Brown, is sort of a legend in the audio world, so perhaps I should accept 3,6,9dB as gospel even though I was taught 6,12,18dB when I was younger.
Boundary effect or boundary interference occurs when the speaker is some distance from the boundary. At the frequency were the wavelength from the sound source to boundary is equal to 1/4 wavelength, you get cancellation. So when you elevate you speaker, you get a dip in the response that is related to the how high the cab is above the floor. Here's a related article: http://arqen.com/acoustics-101/speaker-placement-boundary-interference/
Years ago I adopted the approach of elevating my cabs and aiming them at my ears. My cab generally functions as my personal monitor, and I find strong bass tends to muddy things up and mask what I want to hear. I like my sound on stage to be very clear and articulate so I can hear every little nuance of my playing.
Normally I have full PA support so the audio tech dials my sound in for the audience. Being able to hear myself on stage better means I can turn down so my stage sound, so my amp does not interfere with the PA as much.
In the event my rig needs to carry the room because the bass is not run through the PA, then I may or may not ground stack my speakers. It really depends on the room. If the room is boomy I still prefer the cab elevated. If the room has unusually good low frequency dampening, I may put the cab on the floor.
Elevating the cab works well for me. I like the way it sounds as both a player and an audience member. But it does not work well for everyone. Some bassists, really crave a nice fat low end, and they really don't want to hear the full range of the speakers. My approach does not work well for this type of player.
There is some confusion. Some articles list the gains as 3dB, 6dB and 9dB respectively for half, quarter, and eight space loading, while other articles lists 6dB, 12dB, and 18dB. I will say that the author of the article, Pat Brown, is sort of a legend in the audio world, so perhaps I should accept 3,6,9dB as gospel even though I was taught 6,12,18dB when I was younger.
Boundary effect or boundary interference occurs when the speaker is some distance from the boundary. At the frequency were the wavelength from the sound source to boundary is equal to 1/4 wavelength, you get cancellation. So when you elevate you speaker, you get a dip in the response that is related to the how high the cab is above the floor. Here's a related article: http://arqen.com/acoustics-101/speaker-placement-boundary-interference/
Years ago I adopted the approach of elevating my cabs and aiming them at my ears. My cab generally functions as my personal monitor, and I find strong bass tends to muddy things up and mask what I want to hear. I like my sound on stage to be very clear and articulate so I can hear every little nuance of my playing.
Normally I have full PA support so the audio tech dials my sound in for the audience. Being able to hear myself on stage better means I can turn down so my stage sound, so my amp does not interfere with the PA as much.
In the event my rig needs to carry the room because the bass is not run through the PA, then I may or may not ground stack my speakers. It really depends on the room. If the room is boomy I still prefer the cab elevated. If the room has unusually good low frequency dampening, I may put the cab on the floor.
Elevating the cab works well for me. I like the way it sounds as both a player and an audience member. But it does not work well for everyone. Some bassists, really crave a nice fat low end, and they really don't want to hear the full range of the speakers. My approach does not work well for this type of player.
I'm reluctant because I have nothing like the other commenters' here experience but my comments might be relevant to some others who stop by here and are not touring pros or on the higher end of production.
I have played a bit on home-made plywood stages in small and often uncomfortably shaped rooms (small places designed for drinking and not music). Typically PA is for vocals and keys, sometimes just vocals but an effort is made to give those people good foldback. The stages are often very boomy from the plywood and "whatever the local hardware had cheap" construction technique where every vibration feeds through the floor into the microphones; and the bass is often your worst enemy for muddy or boomy vocals - and heaven help you if the singer dances. Bands often end up playing way too loud because no-one can hear themselves over the drummer. This isn't helped by the fact that the guitar and bass amps are way down on the floor and the sound swishes past your knees and has to hit the back wall and bounce back for you to hear your amp. So you turn up, sensible really... My simple cure is to ensure everyone has an amp stand (preferably tilted) so your amp points up towards where your ears are so you can hear yourself when your sound is on the way out to the audience and not have to wait until its on its way back from the back wall.
I have played a bit on home-made plywood stages in small and often uncomfortably shaped rooms (small places designed for drinking and not music). Typically PA is for vocals and keys, sometimes just vocals but an effort is made to give those people good foldback. The stages are often very boomy from the plywood and "whatever the local hardware had cheap" construction technique where every vibration feeds through the floor into the microphones; and the bass is often your worst enemy for muddy or boomy vocals - and heaven help you if the singer dances. Bands often end up playing way too loud because no-one can hear themselves over the drummer. This isn't helped by the fact that the guitar and bass amps are way down on the floor and the sound swishes past your knees and has to hit the back wall and bounce back for you to hear your amp. So you turn up, sensible really... My simple cure is to ensure everyone has an amp stand (preferably tilted) so your amp points up towards where your ears are so you can hear yourself when your sound is on the way out to the audience and not have to wait until its on its way back from the back wall.
When you say "his page is a little misleading because what he refers to as mechanical coupling is insignificant compared to the Acoustic Coupling" Im undersanding that you believe he implies that mechanical coupling is insignificant.
I dont read that. To me it is clear that his text is intended as an overiew only (he calls it "the basics") but he does clearly differentiate mechanical vs acoustic coupling, and implies bad vs good. The statement "the floor itself (or stage) becomes a resonating surface, a bit like a massive drum skin or giant speaker cone" does not project an image of insignificance. While using simple beer crates as a conflict of interest free example, his text is actually supportive of products such as yours.
Edit: Woops! I just realise that your product is actually for isolating an amp from the cab...(as alluded to by @agedhorse). Since I just bought a YBA100 Im looking just such a gizmo!
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I actually did due diligence looking at the performance of mechanical de-coupling devices to be placed underneath cabs. In fact, that is a much larger "market" than isolating bass heads from the cabs. I was absolutely shocked when my measurements indicated that the only effect was the amount of elevation of the cab. So much so that I literally stood on the stage plate, somewhat in exasperation, while the signal generator was driving the cab, and lifted the cab up and down. The interaction was immediately clear. Light dawns on foggy eyes.When you say "his page is a little misleading because what he refers to as mechanical coupling is insignificant compared to the Acoustic Coupling" Im undersanding that you believe he implies that mechanical coupling is insignificant.
I dont read that. To me it is clear that his text is intended as an overiew only (he calls it "the basics") but he does clearly differentiate mechanical vs acoustic coupling, and implies bad vs good. The statement "the floor itself (or stage) becomes a resonating surface, a bit like a massive drum skin or giant speaker cone" does not project an image of insignificance. While using simple beer crates as a conflict of interest free example, his text is actually supportive of products such as yours.
Edit: Woops! I just realise that your product is actually for isolating an amp from the cab...(as alluded to by @agedhorse). Since I just bought a YBA100 Im looking just such a gizmo!
One necessity in scientifically correct investigation is to follow the data, and not your preconceptions. I periodically am reminded of that fact, and the episode above was one of those reminders.
Acoustical coupling is, in general, a good thing. An Ampeg Fridge is composed of a bunch of relatively inefficient speakers that, when coupled together, have a relatively good efficiency as a system. Acoustical coupling to the room is a bit less predictable, but again, one of the advantages of a fridge style cabinet is it doesn't drive the room from one point - the distributed nature of the source will help to reduce the Q (severity) of some of the room modes - at least those in the vertical plane.
Mechanical coupling to the floor is generally undesirable. A concrete stage will help minimize the effects of this, as those floors don't tend to boom.
My approach to all of this? I play most of my gigs ampless. If the PA and room are designed to work together, then what I do with my rig (acoustical coupling between a bass amp and the PA is a crapshoot) won't hurt a thing - I give the FOH person all the control he or she needs to make me sound good.
Mechanical coupling to the floor is generally undesirable. A concrete stage will help minimize the effects of this, as those floors don't tend to boom.
My approach to all of this? I play most of my gigs ampless. If the PA and room are designed to work together, then what I do with my rig (acoustical coupling between a bass amp and the PA is a crapshoot) won't hurt a thing - I give the FOH person all the control he or she needs to make me sound good.
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Latest Update.....
The last 3 gigs were all different speaker placement ALL outside with no walls. I'm using a single 15 Reeves with the matching C225 head.
......1st was at a party that they brought in an unusable equipment trailer elevated about 2 ft. We played on the grass in front of it. I put my amp on it without a pad and got a very balanced sound with plenty low end coverage. No PA support.
......2nd was at an event with another huge flatbed trailer everyone was setup on it with full PA support and I used my homemade "Auralex" pad. Sound was thinned out and high mids were a little honky.
......3rd was last night at a pavilion with a concrete floor. I decided to try it on the floor- not elevated with just a throw rug. The sound was the best of all 3, and I was grinning all night. No PA support. Very solid low end and balanced. So, in the future, I'm gonna try to eliminate the pad as much as possible.
The last 3 gigs were all different speaker placement ALL outside with no walls. I'm using a single 15 Reeves with the matching C225 head.
......1st was at a party that they brought in an unusable equipment trailer elevated about 2 ft. We played on the grass in front of it. I put my amp on it without a pad and got a very balanced sound with plenty low end coverage. No PA support.
......2nd was at an event with another huge flatbed trailer everyone was setup on it with full PA support and I used my homemade "Auralex" pad. Sound was thinned out and high mids were a little honky.
......3rd was last night at a pavilion with a concrete floor. I decided to try it on the floor- not elevated with just a throw rug. The sound was the best of all 3, and I was grinning all night. No PA support. Very solid low end and balanced. So, in the future, I'm gonna try to eliminate the pad as much as possible.
I recently got a Gramma. and I like the sound and dispersion of my cab on it better. yeah, the low-end response is weaker, but this is something I can live with.
but when I put my cab on the Gramma, it starts buzzing with A and E and it's very annoying.
so my advice is: try your cab both ways and see how you like it better.
but when I put my cab on the Gramma, it starts buzzing with A and E and it's very annoying.
so my advice is: try your cab both ways and see how you like it better.
Try checking the insulation. I had a fluttering buzz and found the insulation had to be re stapled.
