Topic: HRTF Dummy Head

[jacobmyers]

I'm working on a similar project, but am using a filled halloween skull and 2 silicone ears, with AKG C417 lav mics inserted in the ear canal. Initial tests are sounding very good, although the skull is creeping some people out. I will probably add a wig to improve sound absorption, although right now, Harry the Holophonic Head's exterior texture is a soft latex.

Harry is awesome! All "he" needs now is a 6" tall, 2" thick foam-rubber "Mohawk" in the color of your choice (like a pseudo-Jecklin disc) and "he'll" be all set for rawk-recording mayhem. <sark> The silicone ears aren't creepy at all. </sark> But putting a "real" wig on it would be totally creepy.

[digifish_music]

HRTF is based on size, shape AND ABSORBTION characteristics of WATER BASED HUMAN HEAD.  Our heads ABSORBS (not reflects) most ALL AUDIO FREQUENCIES.   

Yours is a head-shaped baffle. I am sure it works very nicely. One advantage of a reflective head-shape is that you can gain some boundary-effect if you place the capsules in the right place...but who am I to speak authoritatively, I will happily use a cardboard box



http://www.freesound.org/samplesViewSingle.php?id=57668

But more seriously, strapping some nice omni-mics either side of a 6" block of wood does work very, very well...that's what I was simulating above.

http://www.trackseventeen.com/soundscapes/mic_rigs.html



I have to get around to making use of this...hard resin head, about 1/2" thick



digifish

[digifish_music]

Thanks for bringing up a good point about patents.  While a patent has exclusivity time limit on infringement, it remains forever to protect a working inventor using the patent established now as PRIOR ART forever. 

This means no one else can legally re-claim patented prior art already established as now their own, and later demanding fees or shutting out the inventor from continuing an established business.   

It certainly does not protect them from competition once the patent expires, so they have 25 years exclusivity to make hay while the sun shines, then it's a free-for all. Hopefully the inventor has moved onto new technology/IP by then, but in the case of simple and important inventions the expiration of the patent brings an end to their profitability as the clones flood the market.

In practice most patents can be worked around by variations on the theme. It has always interested me that you can't patent a recipe (for food) and yet the restaurant/food industry is doing very well thank you    

digifish

   

[digifish_music]

As history has shown, many large companies have shown to ignore patented intellectual property of others, and later have been sued (even after a patent has timed-out losing exclusivity) for very large sums for the period of infringement activity.

...and many have gotten away with it. As you have one or more patents you will know the huge legal costs that can be involved, particularly if you are challenged/challenge others. The challenge process also often involves the case being heard by non-experts and which way the challenge goes can depend (as usual) entirely on the whim of those involved rather than a thorough understanding of the issues contested. There are also very different rules in the EU and US patent systems (and a challenge may require you to act in a foreign country using foreign patent attorneys). It can get messy and take 10 years to sort out. Patent games are not for the poor or faint hearted

digifish

[IanR]

I reckon a large, tight-leaved cabbage, like a red or a white cabbage, would make a pretty decent HRTF baffle. Weighs a few pounds, mostly water, roundish . . . like a head. 

Just bung it in one of those little black stuffsacks you can get from camping shops if you don't want people laughing at it.

[SparkE!]

I reckon a large, tight-leaved cabbage, like a red or a white cabbage, would make a pretty decent HRTF baffle. Weighs a few pounds, mostly water, roundish . . . like a head. 

Just bung it in one of those little black stuffsacks you can get from camping shops if you don't want people laughing at it.

That is an excellent idea!  I've used a bowling ball before and it worked great, but I was very worried about the stand getting knocked over.  That would really hurt if it fell on your foot!  A cabbage wouldn't be so bad.

[IanR]

You could turn it into coleslaw for revenge 

[Gutbucket]

Mmm cabbage.  Delicious idea.

A guy at Magfest a few weeks back had a Zoom recorder sweat-banded to his forehead - I should have snapped a photo.