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Prevue guide music

Posted: Mon May 17, 2010 7:59 pm
by tin
The older music for when the grid looked like on the EPG Sr software - anyone else think it was a .mod file? Perhaps not played by the local machine, but it sounds really mod-ish to me. Any speculation?

Re: Prevue guide music

Posted: Mon May 17, 2010 8:04 pm
by AriX
tin wrote:The older music for when the grid looked like on the EPG Sr software - anyone else think it was a .mod file? Perhaps not played by the local machine, but it sounds really mod-ish to me. Any speculation?
I doubt it, partially because it wouldn't make sense for them to have a machine that parsed out a mod file repeatedly over and over, waste of resources. Also I just don't think it's likely. Could be wrong though.

Re: Prevue guide music

Posted: Mon May 17, 2010 8:35 pm
by tin
Well they deffo had a machine at the centre that provided the c-band listings, and they could have as easily recorded a .mod to tape for broadcast as they could any other music source. Just a theory.

How do you think they got 3 audio sources to the boxes at the cable co? That's one bit of the whole story I can't figure out.

Re: Prevue guide music

Posted: Mon May 17, 2010 8:46 pm
by AriX
tin wrote:Well they deffo had a machine at the centre that provided the c-band listings, and they could have as easily recorded a .mod to tape for broadcast as they could any other music source. Just a theory.
Possible. I just don't see them using that sort of thing for this way back in 1988. I could be entirely wrong. The other thing is that the music supposedly came from some defunct music library called "James & Aster".
tin wrote:How do you think they got 3 audio sources to the boxes at the cable co? That's one bit of the whole story I can't figure out.
I think they just had 3 audio subcarriers on the satellite. I don't know the technicalities of it all, (ask swest77 maybe) but I think they were all transmitted through the same C-band channel.

Re: Prevue guide music

Posted: Tue May 18, 2010 2:02 am
by swest77
To me, the original Prevue Guide theme music just sounds like a vintage 80s keyboard (FM synthesis based or hybrid analog/digital synthesis based).

Semi-pro musician's keyboards (as opposed to Casio crap on the low end and megabuck studio stuff on the high end) sounded very similar back then because they used similar synthesis processes and also of course because they had not yet evolved beyond generating mainly square and triangle and other unnatural waveforms which yielded copious amounts of harmonic overtones. Lead instruments always had a very glassy/chimey sound, bass always sounded very slappy and electronic, etc.

Here's an example of what an ESQ-80 sounded like: http://www.zshare.net/download/7622262528e3b21a/. It's not exactly like the sound of the keyboard used to perform the Prevue Guide theme, but there absolutely are acoustic similarities in many of the instruments' textures and timbres and so on.

In general, people have come to refer to this kind of sound as the "porno soundtrack sound" because these keyboards basically had only one major market: amateur semi-professional musicians ... which in turn was the only kind porn producers could get to work for them. ;)

If there's any similarity between this kind of sound and Amiga .mod files, it's likely because .mod files were a hybrid of MIDI and instrumentation sampling. And the sources used for those samples were often these kinds of keyboards.

In any event, as Ari said the PG theme music was delivered on the Prevue Guide satellite backhaul feed, not played out of .mod files by the local Amigas. Specifically: UV broadcast it from a simple analog loop tape cartridge. As far as how they sent three audio carriers, not difficult at all, commercial satellite transponders have enough bandwidth (in analog terms, 27 to 36 MHz each, depending on the satellite) to carry analog video (which never takes up more than 5 MHz of that) plus many audio subcarriers. Any frequency above 5 MHz can be used and there were common ones like 5.58 MHz, 5.76 MHz, 5.80 MHz, 5.94 MHz, 6.20 MHz, 6.80 MHz, 7.38 MHz, 7.56 MHz, etc. Prevue Guide's backhaul was on Satcom F4 transponder 8 with theme music at 5.8 MHz, left audio at 6.2 MHz, and right audio at 6.8 MHz. (The current TV Guide Channel backhaul is on Galaxy 12 transponder 6 in Digicipher II -- no subcarriers, it's just a big MPEG transport stream carrying video, audio, and data packets. When TV Guide Channel still ran split screen -- instead of 75/25 or 80/20 or whatever it is now -- the video was divided in half vertically, so each local NT machine could choose which vertical half to show in its local top half.)

@Ari - Since you seem to be the expert in this department, you should edit the Wikipedia entry for TV Guide Channel and create a section listing the musical elements previously used by Prevue Guide/Channel. I.e., mention that the original theme is an unidentified James & Aster library piece, that "Opening Act" was the blue grid's theme, etc. Maybe someone will come along, notice the gap re: the first one's identity, and fill it in!

Re: Prevue guide music

Posted: Tue May 18, 2010 4:28 am
by tin
OK I'm going to leave the mod thing for now :) while I hear ya, there's still many attributes to me that make it sound a little too regimented, and umm, how to explain... kind of lifeless (not that I don't love it for what it is) for it to be churned out by a music library. Maybe I'm way off the mark.

BTW your videos are I think the first time that I heard there's a hi-hat going on in the background there - what sort of video recorder do you have, the quality is much better than all of the rest of the videos on youtube etc!

I pretty much guessed the local amiga wouldn't be playing the tunes, as they carry on uninterrupted when the amiga is rebooted ;)

So, while I understand the old school audio subcarriers - we had (maybe still have) an analogue channel here called eurosport that had 5 or 6 different european languages on different subcarriers - I still wonder how they got them all from the reciever to the Amiga to do the switching because there needs to be 3 of them? I presume the Amiga didn't control the reciever to switch subcarrier - or did it? - Maybe there were two receivers, both with their audio L+R plugged into the audio switching card - or maybe it was some kind of professional reciever with 3 or more audio outputs. Perhaps that is some part of how your good friends at continental cablevision managed to screw up the prevue music while the audio from the clips carried on.

Nonetheless, as with everything prevue I find it rediculously interesting :)

Re: Prevue guide music

Posted: Tue May 18, 2010 8:16 am
by AriX
swest77 wrote:@Ari - Since you seem to be the expert in this department, you should edit the Wikipedia entry for TV Guide Channel and create a section listing the musical elements previously used by Prevue Guide/Channel. I.e., mention that the original theme is an unidentified James & Aster library piece, that "Opening Act" was the blue grid's theme, etc. Maybe someone will come along, notice the gap re: the first one's identity, and fill it in!
Good idea, I'll get on that when I have time.

Re: Prevue guide music

Posted: Wed May 19, 2010 10:23 am
by swest77
tin wrote:BTW your videos are I think the first time that I heard there's a hi-hat going on in the background there - what sort of video recorder do you have, the quality is much better than all of the rest of the videos on youtube etc!
Nothing special. You were just hearing linear (non hi-fi) VHS audio from an SP mode recording. (The audio during the narrated portions of the "saddest ever" video was sourced from the http://www.youtube.com/watch?v=RhCn8loYWdc recording's audio track and then processed with an Aural Exciter and equalized on a 30 band EQ. So same theme music audio in both videos, just that it's au natural in the Youtube video and enhanced in the Vimeo video.)

I reckon the reason many of the other videos sound bad is because people often used LP and SLP/EP to record stuff back then. Those never yielded more than AM and less-than-AM radio quality respectively. With analog tape, the faster the tape passes over the head, the greater the frequency response (and the wider the audio track is on the tape, the less hiss).
I still wonder how they got them all from the reciever to the Amiga to do the switching because there needs to be 3 of them?
The Prevue Guide satellite carrier was fed directly via coax/BNC to the Zephyrus 100C cards inside the Amigas, which did their own audio RF demodulation and switching. (The "saddest ever" video's narration was simplified on that note. In truth, I don't know whether this cable company's satellite receiver for the "analog multiplex carrier" itself was delivering a trashed version of it to their Amiga, or if the demodulator for the theme music subcarrier in its 100C card just went bad at one point. Probably the latter. In any case, the part that was true was that this cable company let it stay that way for two and a half years until the whole machine was apparently replaced when they updated to the blue grid software.)

Re: Prevue guide music

Posted: Wed May 19, 2010 6:43 pm
by tin
Aha! all becomes clear, I was confused because I see a few amigas on some of the pictures that have a 4x BNC card on them, and I assumed that was where the audio was input and switched - now I see the light ;)

Re: Prevue guide music

Posted: Sat May 22, 2010 6:06 am
by swest77
tin wrote:Aha! all becomes clear, I was confused because I see a few amigas on some of the pictures that have a 4x BNC card on them, and I assumed that was where the audio was input and switched - now I see the light ;)
Ah, what you were seeing there was a Sneak Prevue A2000. See the very bottom of my post here.