Ground Coupling Learning Experience.

[alanolynn]

So, I decided to go with (2) 2x10 cabs to stack vertically for my current rig instead of my small single 12. Nothing special, but nothing to scoff at either.

My reason for choosing this setup was concluded after much research on TB as well as the rest of the interwebs. The main consensus was that the vertical stack will get more sound closer to your ear without being as loud, therefor making your rig more efficient. At least that's what I gathered.

Sadly, after much tweaking and un-tweaking, I found that I just didn't feel I was gaining any efficiency with the setup. I really wasn't enjoying my sound at all. Kind of thin? So on a whim, I put BOTH vertical cabs on the floor next to each other, and turned the amp back on. BOOM! Coupling for the win! Without any adjustments to the head, everything boosted to the point of having to back off my master volume. So my conclusion is that as long as you have the excess power to drive the cabs in a linear configuration, then you're good. In my case, I have limited wattage, so I guess that's why the coupling works better for me?

Feel free to set me straight. I just felt like sharing my experience with you folks.

 

[2saddleslab]

Always follow your ears.

 

[byacey]

It works both ways, as just about everything in acoustics; It can be a help or hindrance. If you are lacking low end in your overall sound, boundary gain can be your friend, but it can also overpower the midrange content resulting in a lack of definition.

 

[alanolynn]

It works both ways, as just about everything in acoustics; It can be a help or hindrance. If you are lacking low end in your overall sound, boundary gain can be your friend, but it can also overpower the midrange content resulting in a lack of definition.

I can definitely see where you're coming from. I'm sure if the floor were a different material, or if I was/wasn't close to a wall or corner, then the sound would benefit or suffer accordingly.

Thanks for the input!

 

[Rick James]

The ground coupling (boundary reinforcement) of the two configurations is exactly the same, and so is the low frequency response and output. What's different with the vertical stacking is that placement makes the mids and highs much easier to hear. By making them more prominent the lows seem to be less, but they aren't. Whichever way you like it is fine in terms of what you're hearing, but it may not be out in the audience. I always set my cab position and amp EQ based on how it sounds out front, not how it sounds three feet in front of my rig. One thing that's for sure is that it won't sound the same in both places.

 

[alanolynn]

One thing that's for sure is that it won't sound the same in both places.

That's an incredibly invaluable piece of advice. My first gig with the group won't be for another month, but I will be sure remember this. Thank you.

 

[Rick James]

I always get out onto the dance floor to hear my tone, preferably during sound check if we have time to do one. Ten times out of nine if I change the tone from what sounds best on stage to what sounds best out front it's by cutting back on the lows and increasing the mids.

 

[alanolynn]

My normal gig is drumming, so that's the one thing that I can never do. It'll be nice to have more control once this group starts playing out. Thanks again.

 

[Downunderwonder]

exactly

I don't know about ''exactly'' the same but I figure the bottom cab coupling with the floor and the top cab, and the top cab coupling with the bottom cab must somewhat make up for the reduced floor coupling of the top cab in the vertical arrangement.

Somehow I think a player that likes the woofy sound of 4x10 on the floor might not appreciate the vertical arrangement out in the room either.

 

[alanolynn]

might not appreciate the vertical arrangement out in the room either.

I had a 4x10 before the 1x12 and I enjoyed the sound, but it still didn't do it for me. More than likely just due to different build/speakers/casters/etc. These vertical 2x10's have rubber feet, but no casters, so I'm sure that'll have a positive effect on the coupling.

 

[Rick James]

There's no loss of coupling in the upper cab when stacked, because all the drivers will mutually couple, meaning they act like one driver, in the lows in both cases. They don't act like one driver in the shorter midrange wavelengths, but those don't get floor coupling either. If you get far enough away you can't tell the difference in the mids, at least not on-axis. Off-axis is where you'd hear a difference.

These vertical 2x10's have rubber feet, but no casters, so I'm sure that'll have a positive effect on the coupling.

No difference. Boundary reinforcement is an acoustical effect, not mechanical.

 

[Stumbo]

I had a 4x10 before the 1x12 and I enjoyed the sound, but it still didn't do it for me. More than likely just due to different build/speakers/casters/etc. These vertical 2x10's have rubber feet, but no casters, so I'm sure that'll have a positive effect on the coupling.

FOH, coupling is overrated. A stand, HPF, or a rug/pad help limit the mud produced from it.

When you're at a gig, you fight the stage and venue's acoustics to sit well in the mix and help your band sound good. You make whatever adjustments are required. Your "Room tone" at home or rehearsal mean little to nothing.

Best thing you can do is go wireless or get a long chord so you can hear yourself FOH during soundcheck.

 

[JRA]

so I guess that's why the coupling works better for me

well then, OK!

i would couple my cabinet --- anywhere i thought it would be better for the playdown. it usually isn't a great idea for my gigs, but i would do it in a heartbeat if i thought it could be helpful.

you don't have to explain to anyone why you prefer what you prefer. pretty simple. also: there is no 'amp and cabinet police'.

good luck on your relationship with floors and walls!

 

[Razman]

I don’t always couple, but when I do couple, I do it with authority and power.

Edit: And blatant disregard for mismatching drivers, regardless of what anyone on TB has to say about it. (Besides, I cant hear you over the sound of how awesomely loud I am; what was that again, sonny?)

 

[alanolynn]

good luck on your relationship with floors and walls!

Aren't you sweet.

I agree that practice space sound and acoustics vs. gig room sound a acoustics will be completely different. I just felt like sharing my experience with my cabs as a way to help other up-and-comers on TB. I understand the do's and don'ts, and appreciate all of your expert opinions.

Some stuff works, and some stuff doesn't. It'll all sound different to anyone else's ear. I am enjoying the journey through learning, as I'm sure you all did at one point too.

I do it with authority and power

...and malice

 

[alanolynn]

Your "Room tone" at home or rehearsal mean little to nothing

I assume it would if I'm comparing different cabs though. I at least have a neutral zone and starting point. Even if it's not the same at a venue, I'll know that "this cab" is more likely to sound like this and "that cab" sounds differently.

 

[Coolhandjjl]

As mentioned, how did it sound out on the floor full of audience members?

 

[alanolynn]

As mentioned, how did it sound out on the floor full of your fans?

as mentioned.....I haven't gigged with them yet, or even with this group yet.

 

[Stumbo]

In my case, I have limited wattage, so I guess that's why the coupling works better for me?

Which amp are you using?

 

[Wasnex]

There's no loss of coupling in the upper cab when stacked, because all the drivers will mutually couple, meaning they act like one driver, in the lows in both cases. They don't act like one driver in the shorter midrange wavelengths, but those don't get floor coupling either. If you get far enough away you can't tell the difference in the mids, at least not on-axis. Off-axis is where you'd hear a difference.
No difference. Boundary reinforcement is an acoustical effect, not mechanical.

From what I have seen and read on wave theory, this is not true at all propagation angles. The wavefronts of the different drivers line up on axis, but not off axis. Boundary effect is a result of off axis interference, and is related to the time it takes for sound to travel from the source to the boundary and be reflected back to the source. Cancellation occurs where the distance equals 1/4 wavelength. Since a vertical array has multiple sound sources at difference distances from the boundary, they will incur boundary cancellation at different frequencies.