The future of analogue sources

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I think it might be good if an analog Blu-Ray based format were introduced. FM encoding could be used for the actual signal modulation - a reference frequency signal could also be encoded to maximize stability of the recorded signal - it wouldn't surprise me if performance comparable to digital wrt all the major parameters was possible using this format, but without digital level conversion, resolution and sampling artifacts.

Well, they did something like that with Laser Discs... in the 80's... I used to have a bunch. I don't see well enough to say one is better than the other.
 
Hi!
Is there any future of the analog audio sources? I mean is there any real developments in this world or the Digital is unstoppable.

Greets:
Tyimo

After direct-to-disc and Reference Recordings old souped up tape machine many years ago (make that decades?), I don't think much of anything has gone on in analog recording development. There was some guy in California who made an ultimate Ampex 350 tape machine but I can't find it any more. He used FFT to determine which parts were contributing which kind of noise.
 
I think it might be good if an analog Blu-Ray based format were introduced. FM encoding could be used for the actual signal modulation - a reference frequency signal could also be encoded to maximize stability of the recorded signal - it wouldn't surprise me if performance comparable to digital wrt all the major parameters was possible using this format, but without digital level conversion, resolution and sampling artifacts.

Yes, I think that would be interesting. Tape is neat, it looks cool, but as much as I love it, it has thos problems of alignement and lack of high frequency. Rather, it does not have a flat frequency response, and that response is dependant on the tape itself, the biasing, etc.

Using a "digital" method and adapting it to analogue would certainly, if not economically viable and popular, be very interesting... I'll volunteer to make the first prototype.

Somebody know where I should start here? lol

(I have yet to understand fully how cd players work, mostly the "tracking" part of the servo system. It's always been a mystery to me)
 
Well done, I think an analog blu-ray based format should definitely beat tape out as far as SQ. FM has 'digital-like' characteristics such as flat frequency response starting from DC and a noise floor that can be placed low enough to compete with CD, plus straightforwardly implementable low distortion that through its dynamic range, unlike digital's lowest 50 db or analog's top 10db. The Blu-Ray disc standard is recordable and I believe has enough storage capacity to implement these characteristics in real time. And I think it's quite possible to develop the standard so that all the audio circuitry for this standard could be implemented with tube technology if desired.

I won't get into possible tradeoffs for multiple channel options, video etc. here although there's no reason to exclude them - I'm thinking of basically high quality two channel audio.

Plus, when everybody has gone to streaming media, it could keep the format active. Plus, the number crunchers can say 'it's analog, so doesn't need the copy protection of 'perfect' digital', or something of that nature.
 
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Noise, drop-outs? I don't know if I understand here... What is the issue? Are we not talking straight, Radio-type Frequency modulation here? What is the issue with regular FM and noise? It was developed to be immune to noise caused by electromagnetic impulses such as lightning and ignition coils and such.

what are the two "types" of FM you speak of?
 
As far as noise pulses, either momentary muting or a potential redundant modulation scheme could potentially provide a 'fill in' signal. Wrt dropouts, presumably the signal noise margin would allow some immunity from deleterious effects. I assume broadcast effects such as multipath and signal dropouts would not normally be large factors in a dedicated portable medium. The analog FM generator for at least professional use could presumably be optimized in this regard and as far as distortion goes. If the center modulation frequency is high enough, say 10Mhz, wouldn't that minimize analog nonlinearities even with 1Mhz plus frequency offsets?

Incidentally, I recently found out that Ampex Corporation had a FM modulated instrumentation tape machine in production in 1963, using I believe 1" tape that could provide at least 10 channels of DC - 20khz bandwidth audio. Of course, this was at 120 ips so the record & play time was small and I read the S/N wasn't optimal, but that does give an interesting perspective on what has been done in the past. Presumably better can be done today.
 
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It's been my observation that in a lot of cases that as complexity goes up the attributes that most audiophiles seem to be interested in seem to diminish. I still have a laser disk player with both digital and FM sound track playback capability, (an expensive relatively high end Panasonic from way back in the late 1990s) and I can't say that the FM performance is in any way better than the PCM.

I can't imagine that an FM based system is going to sound significantly better than (or perhaps even as good as) properly implemented DXD or even DSD.
 
I have a Pioneer LD and I find that the FM track on some discs actually conveys more audio information than the digital track. This may depend on how both were mastered - back in those days most digital masters would not have been much better than Redbook, so in that case, little difference between the two would be expected with the digital having a likely advantage.
 
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It's been my observation that in a lot of cases that as complexity goes up the attributes that most audiophiles seem to be interested in seem to diminish. I still have a laser disk player with both digital and FM sound track playback capability, (an expensive relatively high end Panasonic from way back in the late 1990s) and I can't say that the FM performance is in any way better than the PCM.

Neat, I didn't even know that existed on CD players. I guess it went the way of the Minidisk, and DCC.

I can't imagine that an FM based system is going to sound significantly better than (or perhaps even as good as) properly implemented DXD or even DSD.

Well, I hate to be the reminder of the initial post, but we're talking about analog methods. Direct Digital Stream and extreme are, well, not analog!
 
FM is only immune to noise in the sense that some FM discriminators become temporarily disabled by a noise pulse. In effect they interpolate - the penultimate error handling mechanism of digital audio. About the best that analogue can do.

There is only one 'type' of FM, but various ways to generate it and detect it. All will suffer from the usual analogue problems or the usual digital problems, or some combination of both.
 
FM: bandwidth about 15kHz, noise floor about 70dB down at best, distortion on peaks unlikely to be much better than 0.2% and often nearer 1%. Needs pre-emphasis to keep noise down, so limited HF headroom. Sharp cutoff filter at 19kHz.

Redbook: bandwidth about 20kHz, noise floor about 90dB down?, distortion on peaks better than 0.01% (?). No need for pre-emphasis. Sharp cutoff filter at 22.05kHz.

About the only parameter in which FM might beat Redbook is distortion at low signal levels.
 
FM:distortion on peaks unlikely to be much better than 0.2% and often nearer 1%.

Last time I measured an FM drive, harmonics were >-60dB.
Now work that out as %

On thing that annoys me is the "latest" digital systems are advertised as "near-CD", "near-FM" and now just waiting for "near-DAB" quality.
At that point I'll give up!

Frank
 
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Neat, I didn't even know that existed on CD players. I guess it went the way of the Minidisk, and DCC.



Well, I hate to be the reminder of the initial post, but we're talking about analog methods. Direct Digital Stream and extreme are, well, not analog!

FM demodulation was only found on laserdisk players to maintain compatibility with older laser disks that had FM sound tracks. I consider the video quality of DVD to be far superior, and long ago stopped buying laser disks.

I am an avid vinylphile, but I felt (feel) compelled to inject some reality into the discussion and to point out that it is unlikely that an analog FM system is going to achieve performance levels approaching 24 or 32 bit high sample rate PCM in practice... More to the point is the fact that there is no viable market for this stuff. My conclusion is that the problems with digital as often as not relate to poor implementation of the analog end of things. Don't take any of this the wrong way, good vinyl still does it for me in ways that no commercial digital recording I've heard quite matches, and that is despite my recognition of the many technical failings of the medium and playback hardware. Oddly enough moderately high sample rate needle drops (2496) on my system come quite close to vinyl performance which surprised me. (A little less depth and other imaging cues)
 
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Live broadcasts of classical concerts by a couple of local public FM broadcasters here in Boston sound excellent despite the medium's limitations, but not much else does.

My FM tuners currently include a Kenwood KT-8005 (the poor man's Accuphase), a KT-6005, and a McIntosh MR-71.. The 8005 has the best overall RF performance (5 gang tuner) which I need in this difficult environment, followed by the 6005 and finally the 71.. These are all quite resistant to HDFM distortion products.
 
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I was always amazed at the sound quality of good HiFi VCR...I had JVC, where you could set the recording level using nice fluorescent display, do not remember model, but it sounded amazingly good...I must say it beat the heck out of cassette decks I had that time, in 80ties. The dowside was that huge size of VCR tape...not too portable.
 
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