sample rate ? 44.1 ?88.2?

[Jope]

Actually, I think "Mad Scientist" is the more appropriate terminology.

 

Are there others out there? - Um, sorry, this was low...

[BobTheDog]

So.. is anyone here writing music anymore or did everyone turn into a scientist?

 

 

-Neil

 

Unfortunetaly I am an Audio/Video software developer with a Science degree, Music is just for fun for me!

 

Cheers

 

Andy

[tiny333]

music? fun ooo

 

now there is a thought!

 

*scratches head*

[nikkik]

@jope: Cool! Often these types of threads deteriorate, many times simply because we all arent sitting around a table having some dinner and drink

 

With an internal synth, upsampling is one way to alleviate (or lessen) the effects of song/session sample rate.

 

@the scientists...LOL!

I prefer to make music, and not worry about the science. But, I like knowing how/why the tools I use work, at least some degree. Put on the "Engineer hat" and I feel one should have at least a little education. Sorta like a guitar player who plays, but cannot change his/her own strings properly...I just always felt learning and teaching were very valuable.

[Logic lost]

rread my post about au plug ins it might help you out...

[Jope]

@jope: Cool! Often these types of threads deteriorate, many times simply because we all arent sitting around a table having some dinner and drink

 

True. Ok guys, my beer is empty, I will have some sleep now... The last one to leave, turn the light off, please!

[blueintheface]

. . . .

 

If the waveform of a constant tone varies from cycle to cycle (and I am not talking about the steps of the digital part but the filtered output of the DAC, visualized on an oscilloscope), you will hear the variations as side noise in some way.

Definitely.

I just talked about steps because they are what's in the digital process and what has to be "justified" to avoid the waveform variations after conversion and filtering.

 

I really don't know what you're talking about.

 

Why would a waveform of 'constant tone' vary from cycle to cyle as a result of digital sampling where - presumably - the original waveform did not?

[Jope]

. . . .

 

If the waveform of a constant tone varies from cycle to cycle (and I am not talking about the steps of the digital part but the filtered output of the DAC, visualized on an oscilloscope), you will hear the variations as side noise in some way.

Definitely.

I just talked about steps because they are what's in the digital process and what has to be "justified" to avoid the waveform variations after conversion and filtering.

 

I really don't know what you're talking about.

 

Why would a waveform of 'constant tone' vary from cycle to cyle as a result of digital sampling where - presumably - the original waveform did not?

 

(Voice from the bedroom) I heard that! Wait a minute... (then back at the computer) Ok. Um, er - now this was still the sawtooth thing. A digitally synthesized sawtooth, nothing recorded from outside, alright? I'm afraid I would have to talk about steps of a staircase again here and that you can't tell exactly how many steps one cycle of the sawtooth wave contains if the sawtooth is set to 1kHz and the sample rate is 44.1kHz. It was just an example. Forget it if you don't like it, but I won't let you go yet.

Next one. Try to synthesize a sine wave with a frequency of 22049Hz at a sampling rate of 44100Hz and watch the samples alter from minimum to maximum and back at each new sample. But because our tone doesn't have exactly 22050Hz which would be half the sampling rate, minimum and maximum walk towards each other as time goes by and meet in the middle after the quarter of a second, then they rise again in the opposite direction and back again... And after a second they are in place again.

In other words: There is an aplitude modulation on the tone where none was meant to be, and no anti-aliasing can help this. The cycles of the output waveform vary over time.

I know, 22049Hz can't be heard, it's just to make the effect as clear as possible, and some intermodulation effects remain at lower frequencies. Years ago I read the sample rate should at least be three times (instead of the theoretical minimum of factor two) the highest frequency you want to reproduce because of what I wrote here.

A P.S. on digital sawtooth synthesis: I made some experiments in the past with having a DALLAS DS80C320 microcontroller synthesize sawtooth waves with different frequencies, so I can exhibit some practical experience here.

And last - did you do the ES1 test yourself? And have you got an oscilloscope? If so, look and listen, I always find this very educational.

It's getting late here - good night. Nice dispute at all.

[Subtonic]

This thread has blinded me with science.

SCIENCE!

[Beer Moth]

 

@the scientists...LOL!

I prefer to make music, and not worry about the science. .

 

Py

 

Harmony = Greek for "pleasing to the ear".

The first application of a scientific approach.

And the basis for our understanding of music.

Ratios.

Oh dear, I'd better not get started....

[BobTheDog]

@jope: Cool! Often these types of threads deteriorate, many times simply because we all arent sitting around a table having some dinner and drink

 

With an internal synth, upsampling is one way to alleviate (or lessen) the effects of song/session sample rate.

 

@the scientists...LOL!

I prefer to make music, and not worry about the science. But, I like knowing how/why the tools I use work, at least some degree. Put on the "Engineer hat" and I feel one should have at least a little education. Sorta like a guitar player who plays, but cannot change his/her own strings properly...I just always felt learning and teaching were very valuable.

 

A little education is a dangerous thing, especially if you use it to prove a point to yourself.

 

Cheers

 

Andy

[blueintheface]

Next one. Try to synthesize a sine wave with a frequency of 22049Hz at a sampling rate of 44100Hz and watch the samples alter from minimum to maximum and back at each new sample. But because our tone doesn't have exactly 22050Hz which would be half the sampling rate, minimum and maximum walk towards each other as time goes by and meet in the middle after the quarter of a second, then they rise again in the opposite direction and back again... And after a second they are in place again.

In other words: There is an aplitude modulation on the tone where none was meant to be, and no anti-aliasing can help this. The cycles of the output waveform vary over time.

I know, 22049Hz can't be heard, it's just to make the effect as clear as possible, and some intermodulation effects remain at lower frequencies. Years ago I read the sample rate should at least be three times (instead of the theoretical minimum of factor two) the highest frequency you want to reproduce because of what I wrote here.

.

 

Unfortunately, I don't have an oscilloscope here.

 

My question would be - in choosing 22049Hz - you are very near the theoretical maximum freq. that can be sampled @ 44.1K and as such - givem that brickwall filters are just not that brickwall, are you witnesing some distortion due to this?

 

44.1K gives some room for manoevre with real-world filtering to allow around 20KHz to be accurately reconstituted, in practice.

 

Do you still witness the same issues with a 20KHz sine wave?

[Jope]

Do you still witness the same issues with a 20KHz sine wave?

 

Aaahhh (stretch)... Back again. Good morning.

(Skip the next part if you like) First let me say I don't want to prove anybody anything like "44.1 kHz isn't enough" or "where's my ultrasonics gone". I'm no "sample-step-hearer" either. And I don't want to be taken as a schoolmaster since I know my theoretical background just scratches the surface. Our approaches to the subject seem to come from different corners; I always need the practical part, the experience, something one can see or feel, thus running the risk of losing the scientific ground under my feet.

My first experience with the ES1 test (or my own DDS experiments) is: Oh, I hear some disturbing oscillations. Second: What do they look like? Third: How can they be avoided? And from here I continue to dive into the theoretical part.(blah blah end)

Now for your last objection. 20kHz is a good example, you will get constrictions of the output wave about every quarter of a millisecond. If you try to compensate the amplitude loss near the constrictions, you will introduce phase jitter that causes audible sidebands. Of course you could generate the expected sidebands separately and subtract them from your wave to level them out, but for frequencies near to the nyquist frequency the effort increases, and this shows up for steep edges like you have them in sawtooth or square waves as well (steep edges mean a bulk of high overtones).

The more the signal's frequency increases or the steeper the edge, the more samples have to be included into anti-aliasing calculations in order to get a clear tone after analog conversion and filtering.

It's not impossible to get better sawtooth waves digitally than the ES1 produces, as other soft synths prove. But be sure the developers had some lack of sleep because of the points I mentioned.

[nikkik]

@jope: Cool! Often these types of threads deteriorate, many times simply because we all arent sitting around a table having some dinner and drink

 

With an internal synth, upsampling is one way to alleviate (or lessen) the effects of song/session sample rate.

 

@the scientists...LOL!

I prefer to make music, and not worry about the science. But, I like knowing how/why the tools I use work, at least some degree. Put on the "Engineer hat" and I feel one should have at least a little education. Sorta like a guitar player who plays, but cannot change his/her own strings properly...I just always felt learning and teaching were very valuable.

 

A little education is a dangerous thing, especially if you use it to prove a point to yourself.

 

Cheers

 

Andy

 

Erm..not sure the intent of the comment...

 

Education is never dangerous. That is the very type of thinking that enables control of masses thru LACK of education. Revise the statement, and a little education CAN be a dangerous thing, as the incomplete nature CAN lead to false conclusions...which COULD be destructive in nature. (of course, this all depends on POV). Regardless, education can never be "at fault."

 

If the statement was tongue-in-cheek, and simply a quick bit of wit, ignore the rest of this please

 

If the statement was meant that I am trying to prove some point to myself, or that I am suggesting that becoming educated is simply a means to prove points to oneself, well, I am sorry you have that feeling. It is a completely false one in my case, but we are all allowed our own opinions. I observe things, as we all do. I become curious. In the process of learning, if something seems to not be logical, I strive to further understand. Santa never made sense to me as a child in the literal sense, and yes, my parents were quite frustrated (initially) over this. As an adult, I have now had SOOOOO many years that I have enjoyed the spirit of the intent, of what it represented. The point? I feel Santa does exist. Although facts point to a different, and very obvious, conclusion, I still perceive Santa as existing in my world. It is implementation, even in as abstract a manner as this is to digital audio and the Laws and facts we have about this. It all comes down to what makes you feel good.

 

I guess my education regarding Santa COULD have led to me becoming upset with my parents, and thru a nasty chain of events, I might have ended up blowing up their house as they slept....or worse... But, the education would not have been the cause. It was never dangerous. My human flaw would have been, plain and simple.

 

Human flaws, false logic, monkey with a loaded gun= ( potentially ) dangerous. Education NEVER equals dangerous.

 

As to using education to provide select bits to prove a point to oneself...hehehe...well, that is quite ignorant to do IMO. I know there are those in this world that will do just that.

 

Example: My friend said all his golden retrievers have been great swimmers. A book I read said retrievers are great swimmers. I conclude: All dogs are great swimmers, so I will simply toss dogs over the side of a boat in the middle of the ocean, and have no remorse if any die...it would be their fault. IF I had tossed dogs over, saw some die, and then read a book that said SOME dogs are good swimmers, and then used that to JUSTIFY my actions as being "OK" (since I could easily disregard the qualifier "SOME" in my own mind as a means to an end that benefits me) then duh, that is pretty ignorant, and it is pretty damn obvious how flawed that is. In reverse, if I read and discussed and then selected the pieces of info I wanted to utilize to form a conclusion that would please me, such as me wanting to believe all dogs can swim...well, then once again, pretty ignorant. And once again, in this case, the education is not at fault, nor was it dangerous. Rather, once again, it was human flaw in implementation that led to a sad, tragic outcome.

 

In the end, I think dogs that can swim believe in Santa, and I am investigating this phenomenom as being the reason for their swimming ability. The more one believes in Santa, the better swimmer they are, and the more likely they will own a dog. And being dyslexic, I could then conclude that Santa is really a swimming god....all gods can swim after all, right?

[tiny333]

?but what sample rate should i use?

[BobTheDog]

?but what sample rate should i use?

 

Back to the original question

 

This is only my opinion:

 

I use 88.2 or 96, my equipment handles it ok and I have a powerfull computer with lots of disk space.

 

For putting to cd you probably want 44.1 or 88.2, for video work 48 or 96.

 

If you have the power/storage/equipment to use a higher sample rate go for it.

 

Cheers

 

Andy

[Jope]

This is only my opinion:

No, it's not...

 

I use 88.2 or 96, my equipment handles it ok and I have a powerfull computer with lots of disk space.

 

For putting to cd you probably want 44.1 or 88.2, for video work 48 or 96.

 

If you have the power/storage/equipment to use a higher sample rate go for it.

 

Cheers

 

Andy

 

It's mine, too! Have a nice weekend

 

Jörg