Less is more - More music on Less discs.

Neat, I was unaware of either of these.

I didn't realise until I went back to vinyl recently that a quieter recording was so they could fit more on a side. I lover these little bits of modified technology that push the boundaries

Loved the bit during the end credits. I'd love it if you kept that going - it keeps people watching out of the corner of their eye to the Patreon list rather than skipping ahead or stopping and it's quite fascinating to hear that sort of story as well. I totally believed the 9th Symphony thing until just now.

The Tri-Micron is fascinating, I really expected that'd destroy the dynamic range or create an enormous amount of crosstalk but it sounds about as good as any record coming out around that time. Really brilliant machine from the good doctor, thanks for sharing this really quite interesting invention.

I seem to recall the Beatles used to record all their vocals on one track while all the accompaniment was on the other - that way you could twiddle the balance control and accompany them with your own guitar or sing along to their accompaniment.. I found the whole Trimicron thing very interesting. I agree that the track walls on the look very regular, almost like a very old mono record. It would be interesting to try playing Trimicron and a modern recording through your audio vectorscope to see what effect this has on the stereo separation - if much of the information is encoded vertically in the floor of the groove, that would explain the 3dB or so reduction in volume

PROTIP: Set Youtube playback speed to 0.25 to get 4 times the amount of entertainment from the video.

'Fewer' discs. Sorry, insufferable grammar pedant! Great video though, I did wonder at the start how it could be accomplished. My money was on a wacky double groove like Monty Python's 'Matching Tie and Handkerchief' album.

Yay, Trimicron! Great to see something that I (probably among others) suggested to Techmoan. Really enjoyed the video being paired with the "extended" CD too. Interesting to think that if you were to rip that CD to mp3 (or, for that matter, a lossless format), your job would only be half done, as you'd then need a program/app to split the channels, then double up the mono channel, before you had a set of listenable files. Loved the little end piece over the credits too. Always wondered when exactly it was that CDs were able to get up to 80 minutes (my memory's saying mid-90s) and how it was achieved.

I used to own that Sony set that's on the desk. Neat little system!

Wait a minute, Splitting 1 stereo into 2 mono tracks? Is this 4 or 8 track all over again for cd?

I really like the additional bit during the end credits. You should do that more often. Many movies and shows do the same. Thanks for making all of these great videos! Cheers!

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As far as another extended format, older Brilliance audiobooks used all 4 tracks of the cassette tape and so held 3 hours per cassette. <a href="https://images-na.ssl-images-amazon.com/images/I/91YroWkgG7L.jpg" rel="nofollow noopener" target="_blank">https://images-na.ssl-images-amazon.com/images/I/91YroWkgG7L.jpg</a> They also had the adapter for Walkman type stereos with no balance control. <a href="https://www.directtextbook.com/isbn/9781561005499" rel="nofollow noopener" target="_blank">https://www.directtextbook.com/isbn/9781561005499</a> You knew you were buying such a format because it was branded that way at the top. <a href="https://www.amazon.com/Sliver-Ira-Levin/dp/1561004588" rel="nofollow noopener" target="_blank">https://www.amazon.com/Sliver-Ira-Levin/dp/1561004588</a> It worked very well before audible.

Have you been shooting any of your episodes with the Blackmagic camera you mentioned a few weeks ago? Perhaps not; but if so, it would be interesting to some (me) if you touched on your thoughts about the workflow with that camera during your upcoming behind-the-scenes "blather-thon!" Seems like a topic appropriate for blather!

The “extended long play” record is a clever mechanical hack: amplitude on a record is deviation of the needle, so reduce the recording volume when cutting and you get narrower tracks. So the “lands” are larger, and the grooves narrower, so you can then pack the grooves in tighter by reducing the lands/negative space. All at the cost of the signal to noise ratio being reduced (so crackle and pops are more obvious), and needing to turn up the volume on playback. For “Lo-Fi” that almost seems worth it, but maybe not for “Hi-Fi” reproduction unless you *really* didn’t want to get up and change sides half way through.... Thanks for sharing the format. (The mono CD, play twice, idea is also a hack, but no where near as elegant.) I love the way you find/share these quirky parts of technology past! Ewen

As I understood it, quadraphonic sound on a CD was was going to be done by halving the running time, not halving the bit rate. 8 bit would have sounded atrocious. I have seen a similar approach to the doubling-the-CD trick on audiobooks on cassette, usually intended for portable cassette players. The tape package would include a splitter device going into the stereo jack and then allowing you to plug your headphones into the left or right output jack of the splitter for the first half or second half of the book. I had always wondered where the whole 44.1 kHz vs 48 kHz decision came in. Consumer DAT units could only record at 48. DVD's use 48. But professional DAT's and CD's do 44.1 . I assumed it was some sort of cost issue in making the A/D converters; 48 was cheaper to do than 44. Otherwise consumer DAT's should have been able to do 44.1 just the same as pro units. I know that they started with the premise of the highest frequency hearable by humans, 20kHz, doubling that to make the minimal parts of such a waveform, and then adding some amount of overhead. But why 44 vs 48?

As always Mat, thanks for creating. I'm a better-informed geek now than I was 19 minutes ago and had never even heard the tale of the chairman's love for LvB as the reason for a CD's length. Those L/R channel instructions need to go: on <a href="http://www.engrish.com/," rel="nofollow noopener" target="_blank">http://www.engrish.com/,</a> your commentary made me chuckle.

Bravo, you had me rolling at "instructions unclear".

Side note 4: About the size of CD's, this is indeed a well-known story. The way I remember it: Philips wanted to make CD's 11.5cm because that way they would be the same size as a cassette case. They had model players (Google for "Pinkeltje") based on this size, and they were already building a factory in Germany that could make 11.5cm CD's. Sony found out about this and realized that Philips was going to be ahead of them with production of CD's, and insisted on the larger size; whether they used the argument of the symphony that wouldn't fit, is not clear in hindsight. But Philips was forced to change all their tooling to be able to make 12cm CD's. By the way, Sony also pulled a trick like that with insisting that CD would have to use 16 bits and 44100 samples per second: Philips already had a D/A converter that was 14 bits (so they had to invent oversampling to play 16 bit sound) and Philips already had electronics that was ready for 44056 samples per second. Sony's argument (which was a good one) was that 44100/16 would sound better and they already made a device to copy digital audio on a video tape. 44100 happens to be the exact multiple of a certain number of samples per video line in an NTSC video signal.

Side note 3: There was a small mistake in your comments: you said the two walls of the groove are 45 degrees apart; that should of course be 90 degrees.

Side note 2: One problem of a dual mono CD-audio that you didn't mention, is that you can't put a track marker on one channel. So if you have two pieces of mono music and you don't want to bother the user with silence, they have to be (about) the same length. By the way, I own an audio CD with BASICODE programs for 1980s/1990s computers that uses dual mono, and the makers of that CD carefully made sure that programs were the same length for each track.

Side note 1: The Red Book standard for Audio CD's actually had a mention of the possibility of quadrophonic sound, which would have made it possible to create that first disc with two stereo programs of 74 minutes each (but there's a catch, see next side note). There were no details about how this would have been implemented, and I think it was removed from later versions of the Red Book. I assume that quadrophonic CD's would have to have 8 bit audio instead of 16 bit audio, or something. The S/PDIF (IEC-60958) standard for digital audio makes it possible to use a couple of bits for a sub-channel of audio, but I'm not aware of anyone using this either.

Great job! And as someone else mentioned, I don't think I could get over the crackles on that vinyl. My childhood was in the 80's, so I grew up with both my dad's vinyl records (mostly rock from the 70's and early 80's) and Compact Discs, since my dad was an early adopter of the CD format. Vinyl records always had some crackling, but this was usually covered up (most of it, at least) once the music actually started. The Trimocron's volume seems to be very low, as you pointed out, so any crackling wouldn't have any chance of being covered up. Btw, nice touch with the add-on commentary during the end credits roll! I really liked that. It's a nice alternative to the puppets (when you don't have the time/effort to include them at the end).

Nice video as ever and good to see some respectable music ;) I remember seeing the CDs that included the gadget for separating the left and right channels reviewed in the Penguin Guide to Compact Discs but never saw them on sale. You're right in saying that it made little sense to cram that much onto a single disc as manufacturing costs would have been measured in pennies but at that time CDs were still being marketed as a premium product with a classical disc typically selling for £13-14. Something like this would have helped to preserve the myth of CDs being a valuable commodity.

20 minutes on each side of an lp is already pushing the limits. 17 or 18 minutes is more realistic and all cutting machines had to arrange the distance between each groove so that there was enough room to accommodate bass frequencies or transients. This was done manually or later automatically by looking in advance the context coming next. Reducing the distance between grooves will result in crosstalk, that is hearing adjacent grooves. You can search the lp by Joe Jackson Blaze of glory. It states on the cover that the dynamic range was reduced because the music was intened for cd use. Just play it Loud!. But it sounds very compressed.

One thing that is true about Compact Disc, though, is that the hole in the middle is the exact size of a Dutch 10 cent coin ("dubbeltje"), before they started using euros. Ah, vinyl. Partially because of this channel (basically, what I'm saying is "it's your fault") I recently bought my first vinyl album since the early 1980s. It's Sabrina Salerno's album "Sabrina". You may remember her, a pretty Italian with an oversized chest and an undersized bikini singing "boys boys boys" in a swimming pool. Perhaps I should buy a turntable, too.

Honestly, not sure I could get over those crackles, though I am a child of the 90s/00s. Were there players or devices that helped reduce that?

I laughed a few times on this one! Mostly from you taking the piss out of that ill-advised CD format. The super-long playing LP is very similar to a format that came out in the States on similar classical/easy listening records known as "microgrooves". I can't find anything online about that at the moment, but I distinctly remember getting an Arthur Fiedler record from a yard sale as a kid with that prominently displayed on it. It also had a reduced volume and dynamic range.

Neat...it is obvious they got the narrow straight tracks by removing bass response.

You’re in fine form on your commentary, subtitles and research on this one. 👏

Matt, your subtitles to Cotton Mouth's instructions are priceless! I've never seen one of these 2-channel mono CDs; guess very few publishers used this technology. Also it is surprising that the Trimocron disk does not suffer from pre-and post-echo, what with the groove walls' close proximity increasing the likelihood that one wall would influence the geometry of its neighbors.

The German band "Die Ärzte" released a live album in 1999. It has two normal CDs with all the songs but also has a 3" CD with lots of talking of the band members, making jokes at each other and so on. Apparently 23 minutes of that wasn't enough so they used two mono channels with different content. Nice idea and who cares if a bunch of people talking is mono or stereo. But many people had problems listening to it because all the boom boxes and low end compact stereos they got had no way of adjusting the two channels separately and everything was in one casing so no way to disconnect a speaker or one cable of the CD player...

I'm surprised that the CD format wasn't designed to handle mono natively, it seems like a massive oversight as I expect it was still reasonably common to hear mono recordings in 1966 when the patent was filed and being digital I suspect (with no technical knowledge of the system) that it wouldn't take much to duplicate the channel. Trimicron is much more impressive and seems like they're only using the movement of the stylus in the vertical plane. I expect these are a bugger to clean as the tracks are narrow and deep, they would just catch and hold on to dust so still hearing crackles and pops is no surprise.

It's amazing what you can do with vinyl when you reduce the amplitude of the recording. Yes, the music fits, but now the noise floor is really high. Radio Shack had a Boston Pops LP that was over 45 minutes per side and some of the old K-TEL records used this technique as well. I keep a few around for doing phono cartridge alignments because they are a little more difficult to track with those fine grooves.

What was the longest duration anybody managed to get out of a compact cassette?