8mm Forum: Projecting sound via Blutooth speaker(s)

This is topic Projecting sound via Blutooth speaker(s) in forum 8mm Forum at 8mm Forum.

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Posted by Mathew James (Member # 4581) on October 31, 2016, 11:55 AM:

Hi All,
I haven't heard this discussed, maybe i've missed something... but just in case, I wanted to make a note that you can project sound via blutooth.
Why would you do this, and what do you mean, you ask?

Blutooth(bluetooth) is a wireless technology, using similar frequencies as the 2.4 band of wireless, like on your routers. Most routers have dualband now(2.4 and 5Ghz) but blutooth works in the 2.4 band.
Anyways, I picked up a beautiful new blutooth speaker by Harman, the JBL Xtreme: http://www.bestbuy.ca/en-CA/product/jbl-jbl-xtr eme-bluetooth-wireless-speaker-jblxtremeblkus-black-jblxtremeblkus/10393238.aspx
...because i've had some issues trying to connect with my laptop to this speaker...i ultimately decided to bypass the laptop altogether and buy this new blutooth transmitter: http:// [URL=http://http://www.bestbuy.ca/en-CA/product/aluratek-aluratek-universal-bluetooth-audio-transmitter-abt01f-white-abt01f/10389798.aspx?path=ae60df8e98d727286f5908bc8722c595en02[ /URL]]w ww.bestbuy.ca/en-CA/product/aluratek-aluratek-universal-bluetooth-audio-transmitter-abt01f-white-abt01f/10389798.aspx?path=ae60df8e98d727286f5908bc8722c595en02[/URL]
...i was amazed at how easy it was to use and how great it connects with my speaker, which btw sounds beautiful for classical music(which i enjoy).
I then had the idea, hey, this should work on an 1/8 jack audio output, i wonder which, if any or all of my projectors have this. I tried it on both my elmo ST1200HD and ST600 and it connected and played immediately.
These speakers(if you are rich reading this-he hee)if you bought more than one could be put around the room wherever, as they hotsync to each other via blutooth.
Problems:
*without a mixer, mono is mono..no matter how many speakers you buy.
*on my ST1200HD, because it has it's own amp, which hums a bit..that hum gets amplified. This is where i need to ask Steve to remind me what i need to ground that noise at the amp beforehand. Others with a better projector that has mixing capabilities could probably get amazing results.

This is just a more modern alternative to other ways we've discussed on how to hook speakers up. It did not hiccup for me at all during playback...and i like it because i can move the sound away from ears at the projector to under the screen where i like it.
*ps: I am in no way affiliated with the products mentioned above. Any blutooth speaker could potentially work, and so could other transmitters. These are just for examples to show exactly what i purchased and worked for me.
**more on hooking up a mixer can be read here: http://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=009628# 000020

Posted by Steve Klare (Member # 12) on October 31, 2016, 12:07 PM:

The joy of a wireless connection like this is you should be able to sidestep any ground loop issues completely. You can't have a ground loop without the "loop"!

I considered a wireless hookup too. Maybe at least in part because I finally got to design a circuit for myself instead at work, I built a hard-wired setup with ground loop elimination. (Either way...)

-I'll have to say, acting as my own boss I was pretty pleased with my work: gave myself a few days off! (I'm employee of the month, too!) -the pay stinks! [Wink]

The trouble you run into with the twin track outputs on the ST-1200HD is they are pretty wimpy as far as signal strength. So when you amplify them enough to make some real sound, you bring up the hiss and hum too. I have my moments I use them to go real stereo, but usually before I shut down for the night I am back to the blended monaural jack on the side of the machine. It may just be two tracks combined into mono, but it just sounds better.

(Who knows? If I had decent hearing in both ears...)

Posted by Andrew Woodcock (Member # 3260) on October 31, 2016, 12:30 PM:

I think this has been raised on a number of occasions now but a split signal in mono from the yellow output socket always provides the best signal input to a separate mixer or amplifier on these projectors rather than using the separate twin green 3.5mm mini jack sockets.

I think the separated green sockets bypass the pre amp if memory serves me right, hence the very tiny signal output strength.

Many of today's home cinema amps and receivers incorporate Bluetooth and Airplay facilities through to our full sized 5.1 , 7.1 or even 10.2 set up's (my own included).

One of these Bluetooth transmitters would really come into its own then I'd say if it was placed after a desk mixer on our projector tables.

Posted by Steve Klare (Member # 12) on October 31, 2016, 12:40 PM:

-As I said, my hearing is not naturally set up for stereo, but even in theatrical settings I've never been blown away by stereo sound.

A few years ago I connected my setup to Doug's GS at CineSea and we didn't check to make sure we got the channels connected correctly left to right. We ran a whole bunch of films that night including several in stereo.

-did we get it right? We still aren't sure! The channel separation wasn't that pronounced. You can see it on the little LED VU meter on my mixer. -Hear it? Not so much!

(Maybe if you listened through headphones...)

Posted by Andrew Woodcock (Member # 3260) on October 31, 2016, 12:51 PM:

the main benefit I've found with Stereo film tracks is that it gives the soundtrack a little more spacial presence rather than actual defined channel separation for effects etc on Super 8mm.

In a large auditorium like Cinesea, I wouldn't imagine it would bring much to the table at all. With two speakers used in mono mode,or stereo mode you'd still get the sound bouncing around the large space and walls to give you this spacial presence that gives it lift.

A bit like singing in a bathroom.

In the home environment with all of those soft furnishings to deaden the sound, mono sounds particularly flat I find especially on musical films.
The stereo facility just gives it a little of that same presence or "lift" I spoke of.

Posted by Steve Klare (Member # 12) on October 31, 2016, 02:55 PM:

-so if you could introduce a little electronic reverb?

What's interesting is the number of stereo prints that will do just fine on a monaural machine. It's pretty rare to run into one that has so much stereo separation that it sounds wrong. (One Example: "Toot, Whistle Plunk and Boom".)

Posted by Andrew Woodcock (Member # 3260) on October 31, 2016, 03:23 PM:

You're right Steve, its just a case of lifting the track slightly, like you say, a little bit of reverb from a decent mixers set of effects to a well recorded Mono print is just as good a finished soundtrack for presentation as a decent Super 8mm Stereo print in a standard home environment.

I use a Numark CM 200 FX when I can be bothered pulling everything out for a show.This has a built in effects panel to give many interesting effects to outputted sounds.

Not too often I hasten to add for an audience of 1 more often than not! [Big Grin]

Ps Derann in their catalogues made quite a point of telling all of their customers that a Stereo film can STILL be played on a mono projector without losing any of the dialogue, so as you say, for Super 8mm purposes, channel separation wasn't so huge you would lose anything of real importance by it.

The best sounding Stereo prints I have, have all been recorded independently from digital modern day tracks.

Posted by Brian Fretwell (Member # 4302) on November 01, 2016, 04:09 AM:

The prints kept the dialogue because the Dolby specification for 3/4 channel Dolby Stereo was that all dialogue would be mixed to the centre speaker and the matrix used meant it was at equal level on both tracks. Surround would also not be lost, just at a lower level, as it was recorded 3db down and out of phase on both channels. Only sounds entirely from either the left or right (I can't remember which) would be lost.

Posted by Steve Klare (Member # 12) on November 01, 2016, 04:56 AM:

It's the right channel that gets lost.

I remember this from messing around with "Toot, Whistle, Plunk and Boom", the action at the left side of the screen is entirely in the left speaker, the action at the right entirely in the right. What you run into with a monaural machine is as the sound moves from left to right, you fade from normal to nothing!

I guess we can take from this that the normal stripe is "Left" and the balance stripe is "Right".

It would be simpler in a machine with a true stereo jack. As it is, instead of Tip (Left), Ring (Right) and Sleeve (ground) you have a tip for each and a double ground to be connected to two tracks, neither of which is marked "Left" or "Right".

-that's a lot to sort out in the dark! (and always some adapter to forget back at the house!)

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