Thanks Enzo.
What I'm trying to find out is people's ability to determine how sensitive to a fixed tone/frequency is, if that frequency is changed VERY slightly, like in my case, 5Hz.
This can be at any freqency, of course, and if, say, a 400Hz tone, or a 4kHz tone is played.
And if those/various frequencies are more/less noticable in change, then say, the 1kHz -1005kHz tone that I tested with.
Also, with a given frequency, how many Hz deviation is perceived as a change.
What I'm trying to find out is people's ability to determine how sensitive to a fixed tone/frequency is, if that frequency is changed VERY slightly, like in my case, 5Hz.
This can be at any freqency, of course, and if, say, a 400Hz tone, or a 4kHz tone is played.
And if those/various frequencies are more/less noticable in change, then say, the 1kHz -1005kHz tone that I tested with.
Also, with a given frequency, how many Hz deviation is perceived as a change.
8 cents is good but not exceptional.
However your conditions are unclear. Switching from 1000 to 1005? With or without reverberation? Or 1000, silence, then 1005? Or hearing the 1005 while the 1000 is still sounding?
Even my dead ears can hear 1000 beat against 1002. But if you do not define the conditions everybody will hear what they want to hear and disregard the rest. And get angry about it!
I'm sorry, my math was in error. One semitone in music is ~ 5.9% change in pitch. This is divided into 100ths for the term 'cents'; so 6 cents would be 0.35% (least detectable); your 0.5 % would be ~ 8.5 cents. Ampex, in research for its VS-10 vari-speed controller for tape machines, determined that the least detectable change was 0.1% (~ 1.7 cents)
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Ok, to clarify some......
You turn on and listen to a 1000 hz sine wave tone....
Turn it off, and a second later, turn on a 1005 hz tone....(same level)
Can you detect a change in frequency?
Doing the same with other tones (400/405, 3000/3005, etc.)
All at a comfortable level of course.
NOW...Reduce OR increase the difference - above or below that original 5hz change.
A definite change would be 10hz and more, right?
How LOW of a change (in hz) does your senses not pick up?
For instance, if that 1000hz were to change to 1002hz, would you notice?
I had a friend in my pre-teen years who could listen to a song on the radio, then pick up a guitar and play the "hook" or the lead line. No matter how much I tried, I couldn't do that. At this time neither of us could read music, or even knew the note names. I could however record that song at 7 1/2 IPS, play it back at 3 3/4 (one octave lower and half speed) and eventually figure it out even if it meant using a bass guitar (again one octave below a standard guitar) and then transposing back to standard guitar pitch.
My friend had perfect pitch. I didn't even come close. By age 13 or 14 he had given up music and his mom sold me his guitar. Now I use a DAW to figure out notes.
I started as a tech in the Motorola factory where police walkie talkies were made. I became a cal lab tech after a couple years fixing all the stuff in that factory. Every radio gets dropped in a fixture called a "coffin" where a 1 KHz tone is played into its microphone at a calibrated SPL to test the transmitter modulation. The exact frequency isn't important but the SPL is. Some of the older test stations used tube type HP audio oscillators to drive the speaker, others used a fixed 1 KHz source from the test equipment and a small amp to drive the speaker in the coffin.
After 12 years in that factory I could hear a 1 KHz tone that was a bit off. It annoyed me so I fixed it. I would definitely notice 1005 Hz back then (1973-1984) . I'm not so sure if I would notice today. Maybe I'll make a test and report back.
My friend had perfect pitch. I didn't even come close. By age 13 or 14 he had given up music and his mom sold me his guitar. Now I use a DAW to figure out notes.
I started as a tech in the Motorola factory where police walkie talkies were made. I became a cal lab tech after a couple years fixing all the stuff in that factory. Every radio gets dropped in a fixture called a "coffin" where a 1 KHz tone is played into its microphone at a calibrated SPL to test the transmitter modulation. The exact frequency isn't important but the SPL is. Some of the older test stations used tube type HP audio oscillators to drive the speaker, others used a fixed 1 KHz source from the test equipment and a small amp to drive the speaker in the coffin.
After 12 years in that factory I could hear a 1 KHz tone that was a bit off. It annoyed me so I fixed it. I would definitely notice 1005 Hz back then (1973-1984) . I'm not so sure if I would notice today. Maybe I'll make a test and report back.
I wired a speaker across the output of my HP8903A audio analyzer. It has frequency steps of 0.1 Hz.
I find that it takes 12 to 14 Hz for me to reliably notice a change in the up direction, but 9 to 11 Hz to detect a change in the downward direction. The tones were played consecutively with no delay in between, and I knew what was coming, so no it's not good test, only a quick one.
Thinking back a zillion years I tended to favor tuning slightly sharp over slightly flat when setting up the intonation on a guitar, which can never be absolutely perfect. Maybe this is my personal bias, maybe it's common. That I can't measure.
I find that it takes 12 to 14 Hz for me to reliably notice a change in the up direction, but 9 to 11 Hz to detect a change in the downward direction. The tones were played consecutively with no delay in between, and I knew what was coming, so no it's not good test, only a quick one.
Thinking back a zillion years I tended to favor tuning slightly sharp over slightly flat when setting up the intonation on a guitar, which can never be absolutely perfect. Maybe this is my personal bias, maybe it's common. That I can't measure.
Yes, of course, if you're the one setting the frequency, and yes if someone else does it (blind test).
It's not about "expecting" the changes, it's about detecting them.
Wiseoldtech and all, this is a very interesting topic. It has been studied and researched extensively since at least the 1950s and probably earlier. A couple of excellent resources are the Journal of The Acoustical Society of America (ASA), and Eric Heller's book "Why You Hear What You Hear". There are others, but these will keep you busy for quite a while. Regarding the ASA, I distinctly remember reading about this topic in the mid/late 1970s, if that helps you to find relevant papers.
pitch is percieved as relation between tones (unless you have perfect pitch, but even then you percieve tones, not frequencies).
so a change from 20 Hz to 25 Hz is a big change in pitch (major third) compared to a change from 10 000 Hz to 10 005 Hz (probably not noticeable).
anyhow, I will try it when I'm at home!
THAT is SOOO disappointing to hear! God, I wish I had a gift like that!! And then he just throws it away.......shame, shame.......
It is reported that people with perfect pitch are not happy with their "gift". So I would not be too envious. Jamming along with the radio was my way to learn playing the guitar. A long way for me who started as a musical zero incapable to tune a guitar or do some rhythm. Gifted or not - there is much you can learn by practicing.
sine waves generated with REW played on a sennheiser HD530 headphone:
- 20 / 25 Hz: very quiet, besides the frequency/pitch 25 Hz seems much louder!
- 50 / 55 Hz: clearly noticeable - nearly a whole tone
- 1000 / 1005 Hz: still clearly noticeable
- 2000 / 2005 Hz: only clearly noticeable if changed during playback. and, I did the change myself, so not sure if i could hear it if it was done without me knowing it.
it was generally easier with low volume!
Comparisons should be done by equal % of pitch change, NOT absolute frequency counts! 50 to 55 Hz is a HUGE difference compared to 1000 to 1005Hz.
I think I was speaking of the gift of being able to hear a song once and be able to play back the lead line right away. MUCH MUCH harder for me. I also had a friend who could do that. I'm still jealous of his gift!!
I think I was speaking of the gift of being able to hear a song once and be able to play back the lead line right away. MUCH MUCH harder for me. I also had a friend who could do that. I'm still jealous of his gift!!