Assume sound quality is equal: Digital or Analog?

Aha! You ought to pick up 'Noise/Music: A History' by Paul Hegarty. A great read.

Might give that a go then. Recognize the artists in the description. One member of my band is huuuugely into Japanese Noise and a bunch of the more experimental guys like Alvin Lucier, Bob Ostertag, and Carlos Giffoni (my favorite) to name a few. Then there's the American artists like Aaron Dilloway. So much going on nowadays with noise.
 
Do any of you have any idea what it takes to keep a top of the line analogue tape recorder clean and up to spec? Digital makes it so you don't need to do any of that. Also, your music is safer in the digital format and will not degrade over time, which is what happens to reels of analogue tape, not to mention generation loss.

And digital sounds great. Listen to Roy Haynes' CD "Love Letters" and tell me that it should have been recorded analogue.
 
Also, your music is safer in the digital format and will not degrade over time, which is what happens to reels of analogue tape, not to mention generation loss.

I agree. I still need to get around to transferring some of our old tapes to digital so they can be saved (not sure why, most of it's pretty rough).

Thanks for the informative post, Duncan. I found this especially interesting:

Tapes are often driven hard and produce a slight compression, which is usually pleasing and helps 'glue' the low-end together on a track - the drums and bass can often fit better together than with purely digital recording.

My impression has long been that digital slices are small enough to fool the human ear, like fine pixellation fools our eyes into seeing flat colours. So I've tended to wonder if the extra "warmth" that many people attribute to analogue was actually an aural hallucination, or maybe an expectation effect. Nice to know there's something real there too.

I think of the digital / analogue process in stages. The instrument (acoustic or electo), the recording gear (tape or direct to digital) and the mixing gear where, as mentioned earlier, the improvements are so great that you might as well say there's only one way to go.

I can do so much more with free software like Audacity today than I could with an expensive Portastudio plus effects units back in the 80s. The only small thing I lose is the ability to adjust the faders while doing the final mix down - which was a bit of an art in itself in the old days.

(Having said that, the other improvements are so great and my ears are not so fine that missing out on doing final touch ups with the faders is a non issue for me, and I mention it only for the purpose of completeness :)
 
My impression has long been that digital slices are small enough to fool the human ear, like fine pixellation fools our eyes into seeing flat colours. So I've tended to wonder if the extra "warmth" that many people attribute to analogue was actually an aural hallucination, or maybe an expectation effect. Nice to know there's something real there too.

That warmth isn't really about the sampling but about the dynamic compression/harmonic distortion, just like valves in a guitar amp. This is another reason why digital can sound a bit more sterile than analogue recording, because once you'd not only have an analogue preamp but a recording medium that also added pleasing harmonics to the sound. With digital you can have neither, so the results are truer/more accurate, but less pleasing to the ear. That's the odd thing, 'analogue' isn't about producing something 'analogous' to what signals go in, it's much more about how it augments the sound in a pleasing way.
 
Above 192 Kb/S, Mp3 is good enough for 99% of listeners, even. Even at lower bitrates, Mp3 is a good codec and I doubt there are a huge number of laypeople that can differentiate between 128 Kb/S and 192 Kb/S. I can (definitely) but amongst the general public? Not so much.

See, I have had trouble getting a straight answer as to whether we can tell the difference between some of these bitrates. I understand the lower bitrates are achieved by removing frequencies the human ear can't detect anyway.

Is there more to it than that? Is it a listening "skill" that anyone can develop, or is it simple physiology/age, etc?


I would love to do a truly blind A/B test and see if I could tell the difference between 128/256/320, etc.
 
MP3 works by using a series of psychoacoustic 'tricks'. The encoder will run a series of analyses on the original file and - depending on the quality required - take out more or less of the original source signal. This is true of any lossy codec and they all work is similar ways, although the algorithm used to determine what is unnecessary is different between each different codec, so they will sound different.

One of the common methods used is to take out frequencies that are masked by others. Some frequencies 'cover up' other frequencies making them difficult to hear and - thus - irrelevant to the mix. Those will be taken straight out with only the prominent frequency remaining. Another technique that is used is take out the fundamental frequency of a note and to leave some of the harmonics. The human ear quite often 'fills in' the fundamental note if we hear the harmonics, so taking out the lowest fundamental is utilised. Out goes a whole set of other frequencies.

There are dozens of these little things that MP3 does.

Then you run into all the 'standard' quality changes. Bit depth, sampling rate, etc.

This article:

http://www.soundonsound.com/sos/may00/articles/mp3.htm

Explains quite a few of them. Even though the article is nearly thirteen years old, the codec (and hence encoding) is still the same. The processes have got marginally better and refined since then but the basic premise and the techniques are the same.

The fact is, that the more we remove from an original PCM recording, the more we notice the distortions and changes - to the point where it starts to sound 'unnatural'. Now, for most people, 128 Kb/S is just about 'good enough', although a lot of people will be able to tell the difference; especially if they're trained (like me) to spot the differences. 192 Kb/S is more than good enough for the vast majority of people (myself probably included) for an MP3 to sound like the original PCM recording. There is a certain skill to it and I can best describe it as a kind of 'graininess' that you get at lower-quality. When you get into very low-quality, it's immediately obvious because the dynamic range and sampling rate (hence frequency output - like up Nyquist theorem) is significantly altered. That does get harder to detect with age because of a natural loss of hearing at high-frequency but if somebody is - theoretically - over the age of fifty or sixty with 'normal' hearing loss, then it's still detectable and obvious.

When mixing tracks though, it always helps to have the highest-quality source file to work from in the first place. When processing tracks, some of the quality is likely to be lost with various manipulations or any distortions made more obvious by processes like normalisation, so working with the best-quality we can prevents that from happening.
 
Do any of you have any idea what it takes to keep a top of the line analogue tape recorder clean and up to spec? Digital makes it so you don't need to do any of that. Also, your music is safer in the digital format and will not degrade over time, which is what happens to reels of analogue tape, not to mention generation loss.

And digital sounds great. Listen to Roy Haynes' CD "Love Letters" and tell me that it should have been recorded analogue.

I've dealt with tape machines (admittedly, not top-of-the-line but decent 16-track machines) and they are a royal pain in the arse. Specialists need only apply if that's all that you're using for a whole session.

They sound lovely but now you can get hold of tape machine emulators that are indistinguishable from the original machines as a plug-in for a DAW there really is no need to use them any more.
 
Duncan, thanks so much for taking the time to post all that. It's so nice to finally come across a person who really knows his sh**. There are a lot of pretenders out there, as I'm sure you know.

Very enlightening.
 
Duncan, thanks so much for taking the time to post all that. It's so nice to finally come across a person who really knows his sh**. There are a lot of pretenders out there, as I'm sure you know.

Very enlightening.

There are a lot of people out there that know a damn sight more than me, too. Thanks though mate - I appreciate it.

It's important that musicians understand the formats that we're using to communicate and how they might effect our art.
 
I would love to do a truly blind A/B test and see if I could tell the difference between 128/256/320, etc.

I've compared moderately high bit rate (224) to 16/44 FLAC on my home stereo, which is probably considered a decent consumer system, as opposed to "audiophile"
with close listening, there is clearly more depth to the FLAC. I wouldn't notice it with casual listening. If I didn't listen to each side by side I might not be able to consistently tell which is which. I suspect that with higher end systems, the difference may be more apparent. or maybe not.
 
I'm just listening through my iTunes library right now with my 'good' headphones on (AKG K701) but running through a small interface that's limited to 44.1/16.

Every now and then I change album, listen for a few seconds and check the bit-rate. I have managed to identify the 128 Kb/S-encoded tracks every time before checking. Between 192, 256 and 320 I can't obviously discern a difference but that might be a limiting factor of the portable interface I'm using. I'll try it again tomorrow through my 'full' interface.
 
"I'm somewhat convinced that analog seems to be the "purer" type of sound and digital is somehow "fake"."

I'd argue that both analog and digital recording systems are not pure. For example, in its strictest sense, distortion is a corruption of a pure signal. Distortion can either occur or be invoked in both analog and digital recording devices and systems. The only difference is that because analog is an earlier technology, many types of music have already established a large repertoire of creative uses for analog distortion, and these have gone on to become canons of recording practice. But there are other more recent contemporary styles which are have found equally creative applications for digital distortion, and which have opened up new avenues for artistic expression.

Much of 20th and 21st century popular music have invoked all sorts of signal processing which, on the one hand can be seen as a corruption of a pure signal, but on the other hand are deemed necessary to fulfill the creative desires of the artist. I've stopped worrying about the analog-digital argument, and focused more on how the inherent characteristics of each paradigm can be deployed to deliver my artistic intentions. I use whatever works. And I 'm thankfull for having both technologies at my disposal.
 
I would have to choose digital, because of the easy accessibility. But, that's just me. I enjoy having the modern technology at my disposal, but I also love the sound of vinyl records (I have a turntable, forgot which model).
 
The binary system of digital recording is, in a way, identical to analog tape. Instead of ones and zeros, tiny magnetic poles on the tape are turned from "off" negative to "on" positive (or is it the other way around, I can't remember...). So, the OP's superstition is unnecessary (as superstitions tend to be).

It has long been known that tape compression/saturation, and the harmonics imparted by preamps and mixing consoles are responsible for analog's desirability. But every year a new plug-in arrives to emulate these features, and they sound better and better. Initially, crappy AD and DA converters and jittery wordclocks were to blame (and you can still find crappy converters in consumer stereos), but that's been addressed in recording interfaces.

The one failure of digital as a medium is monitor mixing. Sending a signal through a computer, and then back into a pair of headphones takes a few milliseconds, whereas in analog the task is instantaneous. As computer processing power continues to increase, though, this becomes less and less of an issue as well.
 
Do any of you have any idea what it takes to keep a top of the line analogue tape recorder clean and up to spec? Digital makes it so you don't need to do any of that. Also, your music is safer in the digital format and will not degrade over time, which is what happens to reels of analogue tape, not to mention generation loss.

Yea, I've been working with and servicing tape machines for over 45 years and I'm still the tape engineer at one of the studios where I work. Tape machines are not as delicate and unpredictable as most everyone thinks. Azimuth is very critical from edge to edge, but very easy to maintain with higher quality machines. We charge a premium for working with tape primarily because of the current cost of the tape, but still our Studers and Ampex machines are kept very busy. Here at my home studios, I make drum recordings on both analog (15ips) and digital formats and pick the analog sound every single time.

The primary reason for tape breakdown was the introduction of "back coating". This turned out, after many years, to be a thorn in the backsides of both Scotch and Ampex. Most of the early tape formulations without the back coating, such as Scoth 111, are still fine and even today are still being used to make digital copies of material that was recorded more than sixty years ago. No one really knows the life expectancy of our current digital media or processes.

I have to use both, it goes with the territory, but I enjoy using analog because it was instilled into me at a very early age.

Dennis
 
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