Audiostrobe mode

I was playing around with the demo version of MindExplorer last night to see what it could do. Looks cool.

I have a question - hope someone has an answer!

When is AS mode, I piped in some normal audio into the Aux of the Proteus. The light glasses started to flash, more or less in time to the music. What's up with that? It happened on a couple of different songs from streaming Internet radio. Shouldn't it only respond to 'coded' Audiostrobe signals?
If it's responding to regular frequencies, won't this add noise to any Audiostrobe sessions I create?

Thanks,
Andrew

Hi, Andrew--

Good question! It appears you discovered a "bonus feature", allowing you to use the AS mode to respond to the higher frequencies of any audio material. ;-)

The AS signal is at 19.2 khz, and when we encode the CDs we "roll off" the higher frequencies of the audio tracks before adding the AS signal. As you experiment, you might try setting your low-pass audio filter to begin rolling off at 10 khz, at for example -12 dB per octave.

Enjoy your Proteus!

-Robert

Hi Robert,
Thanks for the reply.
Just for fun, I used CoolEdit to not only roll off but completely kill all frequencies above -56db and 13,000 hz. This was with a sample bit of music with some voice-over. I'm still getting flashing from the glasses when I play it back through AS mode.
I've compressed the sample so much that it sounds terrible, but I just wanted to see what the cut-off was. There doesn't appear to be one.
I also notice that when playing back the AS sample (the one called Journey of the Drums) I'd also get light pulses that were triggered by the bird sounds. Don't know if this was on purpose or what? I haven't tried the other samples yet.

Is it possible my Proteus needs calibration?

Is there an Audiostrobe specification I can refer to help me? I'm not trying to produce anything commercial - just trying to establish the parameters of the device.

Thanks,
Andrew

By the way - I can upload a small 10-second sample if it would help!

Thanks,
Andrew

Hi Andrew;

Just wondering if by chance you're clipping the audio input to Proteus? If you look at the headphone output of the Proteus is there any clipping present? Clipping of course would create all sorts of harmonics, some of which would fall in the 19.2khz range.

-Andy.

Hi Andy,
Thanks for the reply.
No clipping per say, but I did try a few other things. I found a ghost buzz from my mixer that was causing havoc.
After I eliminated that, I was able to 'silence' the glasses by reducing the output from my mixer to max -20. This is just loud enough to be useful through the headphones, though if you wanted to go even a bit louder the glasses start responding to the volume.
So if I do find a way to create some AS sessions, and I want to play them loud, I'll just have to use the headphone out from the mixer (or CD player or whatever) rather than the Proteus.

Question:
Does the AS mode also generate sounds via encoded signals, or does it just fire the glasses?

Another question:
It seems that the Audiostrobe decoder is 'live', i.e. the glasses flash for every signal it decodes. I would have thought that you would send it changes only. (You'd send a start frequency, and the Proteus happily flashes at that freq until the next 'change freq' signal is sent). I guess not? I guess the frequencies are constantly being sent for each flash?

Another question, if you please:
Is there a public spec for the Audiostrobe encoding? I'd like to write my own software to make use of this feature.

Thanks a lot,
Andrew

Hi Andrew;

I'm glad you figured out what the issue was.
To be honest, many of the limitations you are noticing in the audiostrobe format have been fixed in MP's Synchromuse format. It uses signals to tell the Procyon when to change programs rather than firing "live" from the audiostrobe signals.

Audiostrobe is a copyrighted and closed system I believe, (and not created by MP), but the synchromuse is format created by MP and we would be happy and would encourage any development in that area. It's all open and free to anyone who wants to use it. Any technical information you need regarding the synchromuse format we would be happy to get for you.

If someone were to write some software to enable simple user-creation of synchromuse audio it would be of great benefit to the community.

-Andy.

Thanks Andy.

Is Synchromuse for Procyon only?

Thanks,
Andrew

Yes, only for Procyon.

You are correct--the AS signal is an analog brightness control--the louder it is (at 19.2 khz), the brighter the lights. SynchroMuse, on the other hand, is purely digital--a bit of encoded signal at the start of a CD tells the Procyon which internal session to play, and synchronizes it with the audio.

IT would be very cool if one of our users was into a software project & could create a program which assisted in the mapping of a WAV file to session segments... the pieces we are working on require that we first mark the audio to establish when segment boundaries should occur, then create a session which maps onto it. Not yet quite like painting with oils, but then we aren't software developers & now regard our LS machines as "works in progress" (necessary with between one and two engineers here!)

-Robert