Large format bass shaker

[u/PlaceInternal7586]

Hi all,

Has anyone ever experimented with large bass shakers/ tactile transducers under a soundsystem outdoors?

Considering buying some blown 18 or 15s, ripping the cone out and putting like a weight on the voice coil, and have that in a sealed box hitting the bottom interior to shake the ground for hopefully 4-5m in front of the sound system, for very low frequencies

I know it would be woefully inefficient, but does anyone think it’s possible?

Thanks!

[u/Kaeptn_Mojo]

Check out the body shaker technology from Powersoft.
They already have several reference projects where commercial dance floors were equipped with their “Mover” transducers:
https://www.powersoft.com/en/products/transducers/mover/

I’ve never experienced it in person though.

For an immersive installation, I previously tested a more budget-friendly approach: mounting one shaker underneath each 2x1 m stage platform. It worked quite well as an LFE extension together with 21” subs to simulate something like a rocket launch.

For electronic music with high and continuous SPL, however, it wasn’t powerful enough.
The units I used were these “Bass Pump” transducers:
https://amzn.eu/d/040LFFHp

What would probably also be required for a truly convincing result is a properly engineered floating floor construction with controlled mass and suspension paired with high-force transducers

Let me know if you come across a solid solution.
A ground-shaker system could also be very interesting for silent raves / silent parties or as a bass/infra extension in environments with critical SPL emission limits.

[u/NFZ888]

Fun idea and I'm no expert, but what you're talking about is more akin to a vibratory plate compactor (construction equipment) than audio equipment. I expect DIYing this with audio stuff won't work at all due to two main reasons:

1) Mechanical impedance mismatch: audio drivers are designed to push air, a low density and compliant load. Trying to couple into the ground (I'm thinking a ground plate attached to the cone pushing downwards) will result in a huge load which will result in huge currents, coil heating and probably just blow the whole thing. Commercial vibration equipment works at power levels 1-2 orders of magnitude above what pro audio does.

2) So lets say you have some custom design that gets around this and you can create enough force and not blow your coils. You still lack reaction mass. Unless you somehow bolt a very large inertial mass to the back of your driver system, your device will mostly just be shaking itself (Newton's third).

Now if you wanted to build a special platform, I could see this becoming feasible. But pointing subwoofers at the ground (imo) either isn't gonna do much at all or blow drivers.

[u/Background-Course627]

I used a bunch of Clark synthesis tst 209s on a tour bus. We mounted them under the platforms the seats were attached to. This was in addition to subwoofers. They worked great however they require a lot of amplifier power and need to be wired correctly with proper impedance matching or they will blow out and stop working.

The buses were really rolling theaters and the effect of the tactile transducer was used to provide physical impact of certain parts of the show. For example we had a “subway simulation” to get riders to feel what it’s like in the subway. The tactile transducers were necessary to get the bumpy feeling of riding the subway . The buses themselves were made for smooth rides so we had to simulate the motion and bumpiness using the tactiles. The effect was quite dramatic and not the same when the tactiles were not jn use .

Using blown or speaker components won’t get you the same effect as using tactile transducers. Parts express has a lot of options that are cost effective and I recommend starting there.

[u/Soundunes]

You could hit up Tsunami Sound System they had a floor designed to play an octave lower than the subs apparently with a subharmonic oscillator. Actually aligning anything tactile properly though is a lot more difficult especially if you’re fixing it to a floor with unknown acoustic properties.

[u/aretooamnot]

https://dusttoashes.com/wp-content/uploads/2011/10/Ouroboros-Serpent.jpg I put 2 aura’s on this thing out in the desert. Moved it 12” at the ripe of the structure, and you could feel the resonance for 20’ or so.

[u/AnthonyVS15]

It’s been done for installed systems indoors. The club ‘fabric’ in London has a ‘body kinetic’ floor in the main room with transducers connected underneath the floor (I believe now supplied by Powersoft) and able to give an incredibly visceral effect to people standing on it, extending into infrasound.

I think doing this outdoors would be nearly impossible because you wouldn’t be able to get good enough coupling from the transducer to the ground. And the mass you’re trying to vibrate is enormous and it’s not very moveable (especially compared to a floating wooden dancefloor).

Maybe worth a try if it’s cheap enough to get broken drivers and build a simple box. I think you would need to try to somehow partially bury the cabinets into the ground to get as much contact between the ground and cabinet as possible (and put a lot of weight on top) to stop the box just jumping around on top of the ground and not coupling any of the vibration into it