Jump to content

Reviving The Wi-fi Discussion


kpcrash

Recommended Posts

All,

I have searched and found one thread here that really addresses the question of making an instrument wireless via wi-fi/ethernet and it was a couple of years old. We all know that technology blazes by us at breakneck speed daily. As I have learned in other posts - there are those with quite a knack for electronics on this forum and while I might not be the super genius omnipotent in this regards - I think I can hold my own in a discussion ethernet/wi-fi/radio transmissions, etc. Aside from the discussion about analog to digital (who said all wireless is digital anyway :D ) Has anyone else attempted this privately and gotten any positive results? Gibson's MaGIC project appears to be "swimming with the fishes" as I think it suffered from severe scope creep.

Especially now with some of the pickups available from Roland - how hard would it be to capture that signal into a packet flow similar to 802.11a?

I'm quite tempted to start by hacking a slingbox apart and adding it's components to basic guitar and see what happens. Any thoughts? Dare I say.... opinions? :D

Link to comment
Share on other sites

One question I have....can you do this with sufficient fidelity?

Good A/D interfaces (cf. MOTU 896mk3) sport 192kHz sampling rates on 24 bits....if my math is correct, that's 3.2 Tbits/s which is about 6000 times faster than 802.11a. You'd need serious compression.

Knowing what tone freaks most guitar players are....if you can hear the difference between MP3 quality and CD quality, I think you'd hate your sound through 802.11a.

Link to comment
Share on other sites

If you're building from scratch I think something along the lines of an AM system is going to be much much better than using networking protocals, for a start there are a LOT of devices working on those frequencies and you'd have to have to rig some way of obtaining a link only with your reciver (don't want to be picking up your guitar on your PC or vice-versa). An AM modulator / demodulator shouldn't be to difficult to build, powering a decent transmitter off of 9V batteries might be interesting though, guess it doesn't have to go far.

For installation purposes you're probably talking about routing a new cavity in your guitar to fit the radio board in (you probably wouldn't want it inside your sheilded electronics cavity anyway :D ).

FM will of course be clearer but I doubt you'd be able to tell the differance (so long as you've not got something nearby producing huge amounts of EMI on your frequency). You would be able to get away with much less compression on an FM circuit though I suppose, it'd require a much more complicated circuit though, still easier than doing it digitally IMHO. However if you do want to do it digitally you might as well use a PIC and do it all through programing, much easier than implementing something with discreate components.

:D I don't even think 802.11.x is good for networking!

Link to comment
Share on other sites

you would need some kind of on board processor to convert every thing over then you would have to have another processor on the reciever end.

why not just pick up a good wireless unit rout out a cavity big enough to hold it and then put the controls on the front of the guitar? it would be much easier and a lot cheaper.

Link to comment
Share on other sites

Why not just plug the guitar in and preserve all the tone at very little expense, no batteries and you can carry a spare if it breaks down.

Seriously, unless you are playing stadiums and running around a lot it all seems a bit much. On the rare occasions that I have seen people play in bands wireless, they are hardly moving...mainly because the stage is so small and crowded at an average gig, there is no where to go anyway.

There is also the risk of interference with a lot of wireless systems to my mind and you wouldn't want some kind of fax noise blasting out your speakers should it all go wrong!

pete

PS...of course, as for things like "802.11.x" I have no idea what you are talking about. :D

Link to comment
Share on other sites

Wi-Fi is very buggy but the bandwidth is pretty sufficient. However there's a lot of electronics work going to be needed to implement a guitar that sends packets through Wi-Fi...... some posts here made it sound very simple but i'm not sure how the posters got it explained that way =S for all i know, you will need the following:

AD converter (easy stuff)-> memory buffer -> software (just a ROM would do) that converts the data collected from the AD converter to IP protocol packets -> RF transmitter

now, as simple as it sounds, maybe i'm still living in the stone age but, converting this data you collect from the AD converter into a well formed packet and getting a clocked circuit to send the packets properly is a bit difficult to build unless you can get ur own IC's built. As i see it, you will need the following:

1- a pretty quick processor with lots of register memory (to handle the sampling rate and the large amounts of data needed to get a high quality sound)

2- OR, if you are a software guru and can use a ROM instead of a processor (we did that in college days, but i don't remember what the method name was, it's when you set the address of the ROM as input that you know u'll already get from the previous cct, and then store the action required in that location)

3- another stage to grab the data, divide it into structured packets (a ROM should do i imagine, along with a RAM buffer for the data and VERY well written software)

4- some transmitter circuit.

I can elaborate more if someone's interested, but I personally don't think it's a good idea AT ALL to use any WiFi technology to transmit something that needs no delay or signal loss...... and definitely not a protocol like UDP for example.....

edit: Also, to use any IP related protocol you have to send some sync packets at the beginning, and the circuit will need to have its own address (by circuit i mean guitar) and it will all depend on your receiving station's responsiveness you know, if you have a buggy windows based OS you will take some valuable time hand shaking and connecting to your guitar...

gah i can't stop thinking of WAAAAYS how this can go wrong!

Edited by Sami Ghouri
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...