best wireless sound quality?

[osu1177]

Hi,

My first question is very simple: which of the following formats is the best way to achieve high sound quality through a wireless medium: bluetooth, radio, etc?

I am trying to make a helmet that receives audio wirelessly, and before I order parts and begin assembly I would like to know how to achieve the highest sound quality possible without wires.

Thank you!

-David

[zBuff]

Ok for pure wave at 44Khz/16 bit (ie normal cd audio) transmission either bluetooth or wireless networking(I assume that's what your meant by radio) should easily suffice. A CD reads at 150kpbs, both these standards now easily suppass that data rate, bluetooth 2.0 goes up to about 3000kpbs and certain wifi favours going to over 10000kpbs.

The only thing I would look out for is what your transmission distance is going to be, as both of them drop off in speed as the distance increases/signal decreases. Also whether or not power usage is an issue for your helmet, bluetooth is better in this respect, whereas wifi has far better range (bluetooth only about 10m, wifi 50m, both without boosters)

So this helmet is it for a motorcycle?

[osu1177]

Yes, this is for a motorcycle. I intend to install some sort of receiver and headphone speakers within the pads of the helmet, and then carry with me a portable transmitter connected to my audio source. To transfer the signal I can use bluetooth, radio, etc, I am not sure which one would give me the best sounding audio.

[osu1177]

I forgot to mention, the two units will not be more than 6 feet apart at any moment (hopefully ) as one should be in my pocket or bookbag (the transmitter) and the other installed in my helmet (receiver). A factor to keep in mind is the fact that the transmitter may have to operate through either a layer of clothing or fabric...the receiver on the other hand can be made to be on the outside of the helmet.

any suggestions?

[preiter]

With the noise level you get while riding a motorcycle, do you really need to be so concerned with sound quality?

[FastEddy]

Bluetooth = about 100kHtz digital bandwidth = with room for a single audio channel, barely = POTS telephone quality at best = might be acceptable for monaural motorcycle head set for driver to passenger communications, but not for quality audio.

Wifi 802.11b = about 2 megaHtz (encoded / secure) to about 8 megaHtz (unencoded) digital packetswitched bandwidth on a personal local wireless net = enough bandwidth to download 8 channels of 24 bit, 96k audio = full sound track of a THX video = six to ten 18 bit digital, wireless microphones in a quality performance venue = the Latest Roger Walters (aka Pink Floyd) concert = plenty of bandwidth for a SqueezeBox 2 or SqueezeBoz 3 to feed multichannel, 24 bit 96k Dolby to a quality headset pre-amp.

USB 1.1 wireless = pretty much the same as above Wifi 802.11b.

USB 2.0 wireless = pretty much the same as above times 10.

FireWire wireless = does not exist (yet), but promises to do an even better job on stage than Wifi .b, .g or .n.

Straight microwave radio = about the same bandwidth as Wifi -b but will cook food and might burn your gonads.

IrDA infrared wireless = as bad as Bluetooth ...

[osu1177]

preiter: its a sportsbike, not a chopper or cruiser (which are significantly louder), and the helmet is full-face so I feel I would definitely be able to hear music.

FastEddy: so are you recommending wifi / usb? Ive never heard of portable systems in the way that I described. How do they compare with simple radios, whose transmitters and receivers are easy to use and more importantly, inexpensive?
-david

[FastEddy]

belt holder for iPod, wired head set built into your helmet ... cheapest and least installation "headaches".

To do this trick without a wire from the iPod to your headset, you will need a clean work bench and a lot of inventivness and some luck ... as the 802.11b (or USB 1.1 wireless) chips installed on a custom circuit board will require specialized software for circuit board layout and on board Wifi antenna .... or a big fat pocket full of cash.

[zBuff]

Acutally I'd completely agree with FastEddy, for your usage I'd just go with a wired solution rather than a wireless. Alot easier and hassle free. For what it would take to make it wireless it would cost alot more and the sound wouldn't probably end up being as good, no to mention the chance of cutoffs, and having the charge more batteries etc.

Though I did find this with a google.

http://www.geekzone.co.nz/content.asp?contentid=3006
http://www.sennheiserusa.com/newsite...p?transid=cat2

I'd go with something off the shelf and then modifying rather than building something from the ground up, if you were to go wireless.

Had a really geeky idea though, how about a motorcycle helmet that just has the mp3 player incorporated into it or maybe a caddy system for a iPod, then you have buttons on the side of the helmet for controls and a Heads up Display on your visor Would take a bit more engineering of course, well at least for the HUD.

[osu1177]

Well, I could go wired, but unless I thread the wire through my shirt and attach it to my neck somehow, it will be flapping in the wind. Tolerable, but annoying....and yet something inside me desires to make this geeky. I think you may know what I mean.

Zbuff: I thought about producing a small capacity mp3 player, but the hassle involved in changing the music (unless I make it so the media card is interchangeable) and the price, etc, is not worth it.

Another point is, as mentioned before, in a motorcycle it may be difficult to hear the difference between superb audiophile sound and crummy fm radio sound, and although it would be more desirable for decent quality, it may be less practical in the end. So maybe I will just go with the fm solution.

About the controls: I just clipped a sliding potentiometer I intend to use a volume control on the exterior of the helmet, and thats about it for that. Although track information projected onto my visor sounds fantastic, it would drain the precious battery life...but it sounds tempting...good idea.