why are different bass frequencys felt at different areas?

[no_username 2]

Like high hits are fekt around mid back mainly

Then lower is felt around lower back/butt

Deep hits felt around thighs and legs

Odd and i was wondering why

[ssh 924]

I'm not entirely sure, but this may have something to do with it:

Sound displaces air, and creates pressure. In our skin there are sensory receptors called mechanoreceptors that pick up pressure. There may be more mechanoreceptors in areas with more hair, so that may be a partial reason for having a tactile sensation in one area more then another.

Or I could be full of shit. *shrugs*

[edouble101 314]

[///M5 2,833]

Part of it is just resonance. Same thing that creates rattles, buzzes, and other obnoxious anomalies.

[no_username 2]

Holy shit im laugh. Nice replys! Hell i may be full of shit

Does anyone else notice what i do? I hope im not an oddball here

[Dangrebel 89]

When I hit about 38hz and higher it's pressure on my ears, forehead and chest along with blurred vision . 37 and lower is whole body getting pounded with ear pressure

[jokers10 19]

I know different parts of my car vibrate at different frequencies. At 26Hz, my steering wheel looks like it is about to fall off. A little higher, and my wipers dance. I am sure it is all about resonant frequencies.

[///M5 2,833]

And all that fancy FEA modeling they do doesn't help...yet. American companies are about to start doing what the Germans have now been doing for nearly 10 years and validating these models. They tried before, but not with enough spatial resolution. The Japanese don't even try.

[orlando144 20]

What is FEA? Like when companies say FEA optimized motor structure..

[Julian 641]

What is FEA? Like when companies say FEA optimized motor structure..

The finite element method (FEM) (its practical application often known as finite element analysis (FEA)) is a numerical technique for finding approximate solutions of partial differential equations (PDE) as well as integral equations. The solution approach is based either on eliminating the differential equation completely (steady state problems), or rendering the PDE into an approximating system of ordinary differential equations, which are then numerically integrated using standard techniques such as Euler's method, Runge-Kutta, etc.

[///M5 2,833]

ROFL. Funny definition.

Basically it is a reduction of a complex part into simple structures that then can be attached using known methods so that the understanding of how the final system will work can be calculated. Using this sort of computer aided design mechanism allows predictions of stress, strain, wear, bending, noise propagation, resonance, damping etc. It isn't so easy to simplify and describe.

Of course the whole problem with the technique is the source of it. The little finite pieces that parts are broken down into are based on assumptions that are incorrect. That and it is darn near impossible to model boundary conditions in particular with welds, glued joints, and other non-uniform bonding techniques. Testing is required to validate all of this. While it's much better than the old build it once, test it and see if it is okay it is still a very rudimentary technique. Most high technology companies and products are way beyond just making a model and then building something. Of course the audio world is still stuck somewhere in 1970 as pretty much nothing new has truly been developed that makes a rats ass difference since then. The term in audio is thrown around in a way to say we actually did some engineering instead of just grabbing some random chinese parts and throwing them together which is more the norm. There are a few companies in the US that are above this and do things at least somewhat in the right way, but it's very few...

To put it in perspective though most companies that do FEA spend more than $50k/yr on software and have a handful of well paid engineer's running it. Much more so than standard engineers.

[CrownVic 15]

Very interesting read

[///M5 2,833]

Real equipment with the capability of truly verifying FE models start at around $700k. Ancillary things required. Portions of the models can be verified more cheaply, but not without more assumptions that are usually based on the same ones that the model was in the first place. Not so acceptable IMO.