sunnysal Posted August 10, 2005 Share Posted August 10, 2005 I had another frequency chart (besides the one that parrot kindly posted) that included cymbals and a few other high frequency items, does anyone have a copy of that one? (parrot?) tony Quote Link to comment Share on other sites More sharing options...
Parrot Posted August 10, 2005 Share Posted August 10, 2005 I don't remember who posted the frequency graphic that I just put up again. I liked it when I saw it recently and noted the title on the Klipsch server. Stereophile found some evidence of frequencies stemming from music at up to 30KHz, if my memory is correct. I am skeptical that it would matter. What you want to stay away from, of course, is a so-called brickwall filter that can affect frequencies well below where the filter is set. And some amps go out to 100KHz, not that there is any remote chance of hearing anything out there but (I guess) because in doing so, it ensures ruler flat frequency response in the audible ranges. Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted August 10, 2005 Share Posted August 10, 2005 regarding the possibilities of energy from music up at 30kHz .... I would not worry about the bandwidth being limited by the amp (except for some tube amp designs). The cd player will have an anti-aliasing filter way before 30kHz and the recording microphones will also be bandlimited. Very high frequencies are funny business. The wavelengths are very short, with the consequence that they do not travel very far and can be quite directional. When folks have gone out with the proper recording equipment into naturalistic settings, it turns out there is not much energy at the high frequencies. -Tom Quote Link to comment Share on other sites More sharing options...
sunnysal Posted August 10, 2005 Share Posted August 10, 2005 the highest mention of frequency made by instruments was about 16khz as harmonics, I have not seen any mention of higher frequencies produced as a reuslt of instruments or thier harmonics. regards, tony Quote Link to comment Share on other sites More sharing options...
Parrot Posted August 10, 2005 Share Posted August 10, 2005 http://www.stereophile.com/reference/282/index7.html Some other links can be accessed from this page too. Quote Link to comment Share on other sites More sharing options...
Dflip Posted August 10, 2005 Share Posted August 10, 2005 Another version of the same chart. I don't think it provides any additional information. Don Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted August 10, 2005 Share Posted August 10, 2005 Those graphs from stereophile are very suspect! They mention that one of the recordings was from analog tape and the other from DAT. Neither of those will have information at 30kHz (it was difficult to read the graph). The Nyquist rate from the DAT is lower than 30KHz and the analog tape (?) would insufficient bandwidth. I will not even bring up the issue of whether the microphones would have sufficient bandwidth. There might be energy at 30kHz indicated on the graph (how many dB down?) but I suspect this is from noise somewhere in the chain. The bandwidth of the DAT, micrpohones, & analog tpae will simply not support that sort of bandwidth. But this is all a red herring, since we do not have much, if any, hearing at those high frequencies. Unfortunately, we live live in an industrialized society with lots of noise sources. I suspect we have all suffered some (or considerable) high frequency loss. -Tom Quote Link to comment Share on other sites More sharing options...
Parrot Posted August 10, 2005 Share Posted August 10, 2005 Stereophile wasn't certain what it found either, or what it meant. I suspect as you do that it was spurious. Quote Link to comment Share on other sites More sharing options...
ben. Posted August 10, 2005 Share Posted August 10, 2005 Harmonics of many acoustic instruments would extend past 20kHz. Quote Link to comment Share on other sites More sharing options...
edwinr Posted August 10, 2005 Share Posted August 10, 2005 My hearing starts to roll off around 9 Khz. Anything above this is superfluous. Quote Link to comment Share on other sites More sharing options...
Bonzo Posted August 11, 2005 Share Posted August 11, 2005 Got to be too much power! My old K-horns had blown woofers, mids and tweeters when I got them. Did pay next to nothing for them. The guy was using DIY Hafler mono blocks, 300 watts at 8 ohms a side! The tweeker ran them full bore on a binge one weekend. Do the math! I would be very careful! Some guys think they are indestructable! Quote Link to comment Share on other sites More sharing options...
Groz Posted August 11, 2005 Share Posted August 11, 2005 Well thanks for all advice, I am out of sync with replies being in the UK. Firtly I am 37, male and can hear 19khz test tone through other speakers. Following your other frequency discussions, even bass notes can have a leading edge transient above 20khz, so high frequencies are important. My tweeters appear to be fine and if I put other speakers in the room I can get solid bass down to 30hz easy. I know the K-horns may drive the room differently. So its now getting a bit harder. I am thinking that the treble response from my speakers is perhaps as it should be (droopy) but the bass still seems curtailed. Overall the sound isn't bad enough to suggest a major problem. I wonder if its just the trade off? old design not hi-fi in the modern sense?. Possibly my expectations were too high. I might just have to decide whether or not I can live with the compromises!! Again , thanks for all help. Paul. Quote Link to comment Share on other sites More sharing options...
3dzapper Posted August 11, 2005 Share Posted August 11, 2005 How's this one Paul? I posted the other one the other night but take no credit for it. I found both with a Google one time while researching for a discussion on this same topic. Groz, You could try, by committing a sin as did I, padding the squaker. Rick Quote Link to comment Share on other sites More sharing options...
Parrot Posted August 11, 2005 Share Posted August 11, 2005 Very nice, Rick. The tricky thing is, let's say that there is some 30KHz info of some kind when hearing live cymbals. People can't hear that high, period. Can they perceive 30KHz frequencies some way other than hearing? I doubt it, but how would you test it? Well, you could make a recording and filter out frequencies higher than a certain point. But then you'd be messing with the experiment because your filter could be screwing with lower frequencies too, and that's even beyond the fact that your test is with a recording in the first place, no longer with live cymbals. Quote Link to comment Share on other sites More sharing options...
ben. Posted August 11, 2005 Share Posted August 11, 2005 That graph may show a range in which the bulk of an instrument's harmonics lie, but upper harmonics go well past 20kHz. It obvious that humans can sense sound pressure below and above the limits of auditory perception, but I don't think it's necessary for satisfying musical reproduction. Quote Link to comment Share on other sites More sharing options...
sunnysal Posted August 11, 2005 Share Posted August 11, 2005 but I have seen nothing that suggests instrument harmonics reach above 16mhz more or less. the stereophile article talked about "recorded content" at 30khz BUT did not draw a line between what they saw on the recording and what is produced by instruments. I would love to see something that suggests instruments produce harmonics above 16khz, does anyone have anything like that? thanks, tony Quote Link to comment Share on other sites More sharing options...
ben. Posted August 11, 2005 Share Posted August 11, 2005 Take that high note on a piano with a fundamental at 4kHz. The first harmonic (octave)is at 8kHz, the second (an octave and a perfect fifth above 4kHz) at 12kHz, and the third (two octaves above the fundamental) at 16kHz. From there up, the harmonics get more closely spaced, and I can't vouch for the accuracy of my math for those specific pitches, but the harmonic located three octaves above is still there in relatively high proportions to the fundamental on many acoustic instruments. In this case, at 32kHz. These upper harmonics and their acoustic (and psychoacoustic) interaction play a significant role in the "harmonic wash" of grand piano, something very difficult to capture in recordings when compared to a good piano in a room. The longer string lengths of concert grands allow for greater upper harmonic content, as compared to a baby grand or upright piano. Also, I take issue with the lack of harmonics noted for a pipe organ. Quote Link to comment Share on other sites More sharing options...
ben. Posted August 11, 2005 Share Posted August 11, 2005 Posting on the run... found this, though... http://www.cco.caltech.edu/~boyk/spectra/spectra.htm Quote Link to comment Share on other sites More sharing options...
ben. Posted August 11, 2005 Share Posted August 11, 2005 One example. Interesting read. Quote Link to comment Share on other sites More sharing options...
sunnysal Posted August 11, 2005 Share Posted August 11, 2005 that was indeed interesting ben, thanks! I will need to take my time reviewing the article since it has so much info...he does seem to show significant harmonic content from instruments above 16khz...some of the grpahs are hrd to read, he changes scale from one to the other, etc. regards, tony Quote Link to comment Share on other sites More sharing options...
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