Analogue Verses Digital

Charlie1 · Post by **Charlie1** » 2009-02-19 20:08

A fresh new vibrant topic everyone!

oh, maybe not.

But who cares - It's pretty quiet on the forums at the moment, so thought I'd try and drum up some debate:

In terms of Tune Dem:
1.) Do members think that an analogue recording can ever be more tuneful through a digital source than an analogue source? Is this even possible in terms of Source First theory? What about if a new digital copy is made from the analogue master at studio resolution?

2.) What about digital recordings? Is it preferable to get them converted to analogue as soon as possible and played on vinyl or is there benefit in keeping a recording in naughts and ones for as long as possible?

dlorde · Post by **dlorde** » 2009-02-20 01:20

Is tunefulness a function of accuracy of reproduction?

If so, I would think an arbitrarily high resolution digital recording will be indistinguishable from an arbitrarily accurate analogue recording, both in theory and in practice...

Will we ever get there in practice? Yes, I think the DS series points the way quite clearly. Are we there yet? I don't know, I've not heard the best analogue sources available.

As for storage, it seems clear to me that, given current digital technology, a digital recording is far less likely to degrade than an analogue one (if the state of my old vinyl is anything to go by), so keep it digital until you need to convert it. Each conversion DA or AD will potentially degrade the data.

Moomintroll · Post by **Moomintroll** » 2009-02-20 12:15

dlorde wrote:Is tunefulness a function of accuracy of reproduction?

It's a function of accuracy of pitch reproduction, surely?

'troll

dlorde · Post by **dlorde** » 2009-03-02 00:52

Moomintroll wrote:
dlorde wrote:Is tunefulness a function of accuracy of reproduction?
It's a function of accuracy of pitch reproduction, surely?
'troll

OK, that's fine by me. I asked the question to discover whether there might be any suggestion that less accurate reproduction might be more tuneful (similar to the idea that the harmonic distortion of valve amplifiers can be more appealing to some listeners than the less distorted amplification of solid-state amplifiers).

Post by **lejonklou** » 2009-03-02 11:01

I don't think that tunefulness is a function of accuracy of pitch reproduction, except in a few cases. Because some products that are not very tuneful can't in any way be shown to alter the pitch of what they reproduce.

Regarding the expression "accurate reproduction", it turns into a discussion about what is meant by "accurate"... Accurate in what aspect?

I have reached a few conclusions regarding how to make electronics that appear as tuneful to the ears. One is that distortion should preferably be of a certain blend, while the total amount is less important.

An example: An amplifier has 1% of distortion. Half of that distortion is odd harmonics and the other half is even harmonics. By altering the design with tweak A, nearly all of the odd harmonics can be eliminated. Another tweak, B, will eliminate nearly all of the even harmonics.

Most likely, both tweak A and tweak B will result in a less tuneful amplifier. While the amount of distortion is lowered in both cases, the blend becomes more annoying to the ear and the music reproduced will appear as less tuneful.

Charlie1 · Post by **Charlie1** » 2009-03-02 13:48

Lejonklou wrote:I don't think that tunefulness is a function of accuracy of pitch reproduction, except in a few cases. Because some products that are not very tuneful can't in any way be shown to alter the pitch of what they reproduce.

I was totally accepting of Ivor's proposal that tunefulness is down to pitch accuracy. Well, it makes perfectly logical sense doesn't it!? However, your unique understanding through your own product development has questioned that for sure.

It also makes more sense in a way as I have often read how some turntables with DC motors are much better able to accurately control pitch. Yet, the LP12 doesn't (YET) have DC, but it's more tuneful than the competition.

Moomintroll · Post by **Moomintroll** » 2009-03-02 14:50

lejonklou wrote:I don't think that tunefulness is a function of accuracy of pitch reproduction, except in a few cases. Because some products that are not very tuneful can't in any way be shown to alter the pitch of what they reproduce.

Most likely, both tweak A and tweak B will result in a less tuneful amplifier. While the amount of distortion is lowered in both cases, the blend becomes more annoying to the ear and the music reproduced will appear as less tuneful.

Sorry Fredrick, but you've either lost me completely, or we have a problem with terminology here. My use of the word "tunefulness" refers to the ability to (for better or worse) perceive the tune(s) being reproduced. Surely, the pitch of each note, in relation to the next one, is vital in this?

I don't regard "tunefulness" as a "pleasant" sound (or a nasty one) just that things played more in tune are easier to follow and listen to.

I'm intrigued at your suggestion that "some products that are not very tuneful can't in any way be shown to alter the pitch of what they reproduce." How are you measuring this?

'troll

Post by **lejonklou** » 2009-03-02 15:10

Hmm... I might be misinterpreting the concept of pitch and confusing it with fundamental frequencies and harmonics. Since I'm not educated in music theory, I'm happy to be corrected if I misuse some terms.

If pitch=perceived pitch, then I agree that tunefulness must depend a lot on pitch accuracy. Perhaps Ivor defines tunefulness as perceived pitch accuracy?

But when measuring fundamental frequencies and harmonics, I don't find that minimising the total amount of distortion (addition of harmonics) necessarily results in the most tuneful result. If that had been the case, the perfect amplifier would already have been invented.

Rather it seems that, at least below a certain level of distortion, the relative balance of some types of distortion is more important than a further reduction of the total amount. Now, if these balances have already been identified as having the least effect on perceived pitch, then there has been work done in this area that I would very much like to read.

Post by **lejonklou** » 2009-03-02 16:44

I found this definition of pitch on the web:

1. Pitch is the property of a sound and especially a musical tone that is determined by the frequency of the waves producing it: highness or lowness of sound. (Webster)
2. Pitch represents the perceived fundamental frequency of a sound. (Wikipedia)
3. Pitch is that auditory attribute of sound according to which sounds can be ordered on a scale from low to high. (ANSI)

Does this mean that pitch is debateable, just like tunefulness? In that case I had misunderstood the term. Pitch is always the same as perceived pitch, and there is no exact physical definition (contrary to what Webster says above).

I agree that perceived pitch is vital for a tuneful reproduction of music. Whether something else is also incorporated in the concept of tuneful, I don't know.

Could someone please add their knowledge and possibly help me with the definition of these terms?

Music Lover · Post by **Music Lover** » 2009-03-02 17:10

Pitch = frequency
Important but not the ONLY important aspect.

According to me the other two most important ones creating a tuneful reproduction are:
Amplitude. I.e. the tone has to start, building up to max, decay and stop with the correct amplitude at each moment.

Timing - all tones (described with frequency and amplitude) must be replayed at the correct time - regardless of the frequency. I.e. to be in sync.

Post by **lejonklou** » 2009-03-02 20:23

Music Lover wrote:Pitch = frequency

No, pitch is the perception of a fundamental frequency. That seems to be the correct definition, which I wrote about above.

Amplitude. I.e. the tone has to start, building up to max, decay and stop with the correct amplitude at each moment.

Yes, this should be important as well.

Timing - all tones (described with frequency and amplitude) must be replayed at the correct time - regardless of the frequency. I.e. to be in sync.

I agree that this would matter if it was wrong. But in a lot of electrical equipment, the timing related problems are minimal. I'm certain that what's often perceived as timing problems is in reality something else.

Rather interesting that nobody's mention timbre. That holy grail of HiFi!

Music Lover · Post by **Music Lover** » 2009-03-02 22:27

lejonklou wrote:
Music Lover wrote:Pitch = frequency
No, pitch is the perception of a fundamental frequency. That seems to be the correct definition, which I wrote about above.

What is the difference of a C and the perception of a C?

What I mean with the frequency is that all of them should be reproduced without any of them being off = slightly too high or low. (example; C plus 1Hz)
And with all the C harmonics (other corresponding frequencies) reproduced correctly...

Is that what you mean?
Or am I off :mrgreen:

Music Lover · Post by **Music Lover** » 2009-03-02 22:30

lejonklou wrote:I'm certain that what's often perceived as timing problems is in reality something else.

and that is...

Example:
So what is it when a sub play the bass tones slightly after the music?

StellanH · Post by **StellanH** » 2009-03-05 17:45

Hello,

just my spontaneous thought of what a music signal is:

1.frequency
2.amplitude
3.timing (=changes of 1 and 2)

Surely 3., which means is how well the 1 and 2 information is updated, will have something to do what is perceived as tuneful.

I mean, some digital sources I have heard have zero "wobble" in a constant frequency but nevertheless sounds totally tuneless.

It can also be compared with LCD monitors for TV: as long as the picture is a still the resolution is razor sharp. However, when things start to move the lag in updating is awful compared to an old CRT monitor. I cannot stand it.

Post by **lejonklou** » 2009-03-05 21:10

Music Lover wrote:What is the difference of a C and the perception of a C?

The difference is that we as humans interpret the pitch differently when harmonics are added. Even if the fundamental frequency is the same, we can e.g. perceive it as a slightly higher tone if some harmonics are added.

What I mean with the frequency is that all of them should be reproduced without any of them being off = slightly too high or low. (example; C plus 1Hz)

Yes, and that was precisely what I meant in my first post: That very few parts of the reproduction chain will actually change the fundamental frequencies. But many parts add harmonics, which can make our hearing interpret it as a different pitch.

Stellan: I am with you.

And I hate lag too, but some LCD and Plasma displays are really good. Make certain you tune the settings of the display, often picture enhancing circuitry will cause lag.

Music Lover · Post by **Music Lover** » 2009-03-06 10:12

lejonklou wrote:
Music Lover wrote:What is the difference of a C and the perception of a C?
The difference is that we as humans interpret the pitch differently when harmonics are added. Even if the fundamental frequency is the same, we can e.g. perceive it as a slightly higher tone if some harmonics are added.

What I mean with the frequency is that all of them should be reproduced without any of them being off = slightly too high or low. (example; C plus 1Hz)
Yes, and that was precisely what I meant in my first post: That very few parts of the reproduction chain will actually change the fundamental frequencies. But many parts add harmonics, which can make our hearing interpret it as a different pitch..

Ok, then we have same definition of pitch!
= ALL frequencies must be reproduces correctly so all parts of a tone, basic frequencies with its additional harmonics can be heard.

Music Lover · Post by **Music Lover** » 2009-03-06 10:24

Music Lover wrote:
lejonklou wrote:I'm certain that what's often perceived as timing problems is in reality something else.
and that is...

Example:
So what is it when a sub play the bass tones slightly after the music?

Great to get your thoughts on this, I think this is a very interesting topic.
Getting the frequencies and amplitudes correct going to enhance the tune - we agree on that, but are you saying that these are the only reason for perceived timing problems?

What happen when a speaker is moved, active filter adjusted (mainly amplitude changes), when a IC or power cable is changed, when a cable is put in another direction...

Post by **lejonklou** » 2009-03-06 15:20

Your question is too large and difficult! :D

What I have found is that in electronics, very small amounts of distortion can be perceived as "Oh no, the timing is completely off! This sounds terrible".

But much larger amounts of distortion - of a different kind - can be perceived as "Ok, the sound is a bit distorted, but timing is still fine and I can enjoy this".

I don't have more than a glimpse of understanding of all this. I see certain patterns and try to make use of them in a methodical way.

hcl · Post by **hcl** » 2009-03-06 18:56

Interesting topic!

I am slowly moving towards the opinion that we perceive not only pitch by the spectral distribution but also the perceived timing of different tones being played. A good example is the rather big differences perceived from very small changes in speaker positions. Surely the small position changes has nothing to do with the timing of the music being played, but even small chanes may have big influences on the frequency responce.