Forums

transient

Started by Unknown June 7, 2004
Hi,

My mother-tongue isn't English. What does it mean "transient" in music
signal processing world? I have found physics meaning: transient - (physics)
a short-lived oscillation in a system caused by a sudden change of voltage
or current or load

Best Regards,
Andrzej


Andrzej Kaczor wrote:

> Hi, > > My mother-tongue isn't English. What does it mean "transient" in music > signal processing world? I have found physics meaning: transient - (physics) > a short-lived oscillation in a system caused by a sudden change of voltage > or current or load > > Best Regards, > Andrzej
A transient is that part of the sound that decays more rapidly than the rest. The clang sound of a bell is an example. Play a piano note in the bottom range that uses only a single string. Then, with the damper off but the string silent, pluck it. The two sounds will be different because the transients are different. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Uzytkownik "Jerry Avins" <jya@ieee.org> napisal w wiadomosci
news:40c4c80e$0$2934$61fed72c@news.rcn.com...
> > My mother-tongue isn't English. What does it mean "transient" in music > > signal processing world? I have found physics meaning: transient -
(physics)
> > a short-lived oscillation in a system caused by a sudden change of
voltage
> > or current or load > > > > Best Regards, > > Andrzej > > A transient is that part of the sound that decays more rapidly than the > rest. The clang sound of a bell is an example. Play a piano note in the > bottom range that uses only a single string. Then, with the damper off > but the string silent, pluck it. The two sounds will be different > because the transients are different.
Hhmmmm... What is "part of the sound that decays more rapidly than the rest"? Could You explain in frequency domain? A transient is a frequency range of the sound that is attenuated faster (in time) than the rest. I'm right? Andrzej
Andrzej Kaczor wrote:

> Uzytkownik "Jerry Avins" <jya@ieee.org> napisal w wiadomosci > news:40c4c80e$0$2934$61fed72c@news.rcn.com... > >>>My mother-tongue isn't English. What does it mean "transient" in music >>>signal processing world? I have found physics meaning: transient - > > (physics) > >>>a short-lived oscillation in a system caused by a sudden change of > > voltage > >>>or current or load >>> >>>Best Regards, >>>Andrzej >> >>A transient is that part of the sound that decays more rapidly than the >>rest. The clang sound of a bell is an example. Play a piano note in the >>bottom range that uses only a single string. Then, with the damper off >>but the string silent, pluck it. The two sounds will be different >>because the transients are different. > > > Hhmmmm... What is "part of the sound that decays more rapidly than the > rest"? Could You explain in frequency domain? > A transient is a frequency range of the sound that is attenuated faster (in > time) than the rest. I'm right? > > Andrzej
I was describing how the signal changes with time. I don't know of any frequency-domain description. Another example is an organ note. It can be sustained indefinitely; the unchanging tone when it is held is the steady state. When the note is first sounded, it begins softly, then increases in volume. (Recorded and played backward, it sounds like a piano note dying away.) The changing part of the note is the transient. Technically, in mathematical terms, the early part of the note consists of two parts, the steady state present from the start, and a decaying transient which, added to the steady state, produces the actual early waveform. Jerry -- Engineering is the art of making what you want from things you can get. &#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;
http://www.hyperdictionary.com/dictionary/transient

--smb
Andrzej Kaczor <kaczorandrzejNOSPAM@poczta.onet.pl> wrote in message
news:ca2n5t$sjr$1@news.onet.pl...
> Uzytkownik "Jerry Avins" <jya@ieee.org> napisal w wiadomosci > news:40c4c80e$0$2934$61fed72c@news.rcn.com... > > > My mother-tongue isn't English. What does it mean "transient" in music > > > signal processing world? I have found physics meaning: transient - > (physics) > > > a short-lived oscillation in a system caused by a sudden change of > voltage > > > or current or load > > > > > > Best Regards, > > > Andrzej > > > > A transient is that part of the sound that decays more rapidly than the > > rest. The clang sound of a bell is an example. Play a piano note in the > > bottom range that uses only a single string. Then, with the damper off > > but the string silent, pluck it. The two sounds will be different > > because the transients are different. > > Hhmmmm... What is "part of the sound that decays more rapidly than the > rest"? Could You explain in frequency domain? > A transient is a frequency range of the sound that is attenuated faster (in > time) than the rest. I'm right?
Well transients are usually the things that don't show up in standard frequency analysis! They are usually the "starts" and "stops" of signals, or in musical terms, the attack and release. Think of a plucked guitar string. The percussive pluck sound is the transient, whereas the slowly decaying tone is not. A snare drum hit is often described to be a transient sound because there is no steady-state. As a loose definition, transient and percussive are roughly similar terms. If you want to consider the frequency domain, you could do multiple short term FFTs on the signal. In my guitar pluck example, near the beginning of the sound, you would see a fairly broad-band noise-like component. That would die away after a short time (maybe tens of milliseconds?). Then the frequency domain would look fairly steady with components and the fundamental and harmonics of the note plucked. If you then muted the string suddenly with your hand, you would see another noise-like band "thump" transient component. Some sound editing programs such as CoolEdit allow showing this type of display for a signal. It's called Spectral view in CoolEdit, or sometimes I think it is called a voice print. I hope this is helpful! -Jon
Generally it means the same there, for example the "attack" portion of
a sound.

A short lived, usually stochastic and broad spectrum perturbation due
to a rapid change in parameters at the onset or during the production
of a sound.

--smb

I see that JOS has a similar definition:
http://www-ccrma.stanford.edu/~jos/tvar/Definition_Transient.html
Jerry Avins wrote:

(snip)

>> Hhmmmm... What is "part of the sound that decays more rapidly than the >> rest"? Could You explain in frequency domain? >> A transient is a frequency range of the sound that is attenuated >> faster (in >> time) than the rest. I'm right?
> I was describing how the signal changes with time. I don't know of any > frequency-domain description. Another example is an organ note. It can > be sustained indefinitely; the unchanging tone when it is held is the > steady state. When the note is first sounded, it begins softly, then > increases in volume. (Recorded and played backward, it sounds like a > piano note dying away.) The changing part of the note is the transient. > Technically, in mathematical terms, the early part of the note consists > of two parts, the steady state present from the start, and a decaying > transient which, added to the steady state, produces the actual early > waveform.
I think that fits the mathematical definition, and also should be true for audio. But I think more important is that in audio transients are often higher amplitude than steady state which requires more audio power to properly process them. Consider a drum, where the signal is pretty much all transient. As the human auditory system responds, more or less, to the average power level, but transistors and amplifier power supplies must be sized to the peak, the distinction is important. -- glen
Stephan M. Bernsee wrote:

> http://www.hyperdictionary.com/dictionary/transient > > --smb
Sorry: "www.hyperdictionary.com cannot be found" Jerry -- Engineering is the art of making what you want from things you can get. &#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;
Works for me, but interestingly gives the exact same definition that the OP's
first post listed:

> > My mother-tongue isn't English. What does it mean "transient" in music > > signal processing world? I have found physics meaning: transient - (physics) > > a short-lived oscillation in a system caused by a sudden change of voltage > > or current or load > > > > Best Regards, > > Andrzej
So it's not too helpful since the OP already knows that! "Jerry Avins" <jya@ieee.org> wrote in message news:40c5bc62$0$2921$61fed72c@news.rcn.com...
> Stephan M. Bernsee wrote: > > > http://www.hyperdictionary.com/dictionary/transient > > > > --smb > > Sorry: "www.hyperdictionary.com cannot be found" > > Jerry