quote:
Originally posted by Mike
Cookie, do you thing that an old Amstrad computer might be able to do it?
No...
To do such tests, you must have specialized speakers able to produce very low and very high frequencies. Such speakers are expensive and can only be found in the top range of audio equipment.
quote:
Originally posted by Mike
I remember the speaker making (really?) high frequencies that I could just hear (dont remember the frequency range). Do you think that these old speakers could produce high frequencies? (lets not forget that the old computers could only make music from the speaker, so they might needed some more frequency ranges)
In general a speaker can often produce a somewhat "high" frequency, but for the low frequencies you need a different speaker. In general, the smaller the speaker (in dimensions) the worse it is to produce low frequencies. To produce a good low frequency you need a relative large speaker cone and a very big air volume to move (aka: big air chamber).
As for old speakers compared to new ones. It is the newer ones which can produce, again in general, lower frequencies than the old PC speakers. But this lower frequency is almost always produced by electronical alteration of the signal (eg: "Bass Boost"), in other words, although the frequency range is lower, the signal isn't a pure frequency anymore, but an altered signal again a reason why such tests aren't accurate on such speakers).
The bigger and more expensive the speakers are, the better result such tests will produce. Though it will still be inaccurate though.
quote:
Originally posted by Mike
Also, I don't remember hearing any clicking sounds...
The "clicking" is mostly heared at the beginning or end of a sound. If you do hear clicking, the speaker can't decently cope with the signal and you reached (almost) the end of the range the speaker can produce.
However, this clicking can also happen during the played frequency and can be so fast that it appears to be a pure signal. But in fact it is the on and off clicking you hear from the speaker instead of the frequency itself. (eg: this happened while I played that "new" high-freq ringtone with my speakers. I indeed could "hear" the high frequency, but in fact what I heared was the extremely rapid clicking of my speakers (I know it was the clicking because the thing I heared was too low in frequency to be that high frequency they talk about; and frankly I thinnk many people will report that they hear it, while in fact they hear the clicking and not the pure frequency).
Also the fact that MP3's are used for this test, is not good. MP3's are (like JPGs) compressed. It is exactly the fact that certain frequencies and amplitudes etc can be replaced by others that you can compress MP3's. In other words, an MP3 is the worst audio format you could use for something like this.
If you are interested in all this, such home-made tests are fun to do, and interesting. But they do not produce accurate results and it extremely highly depends on the equipment used.
If you're very serious about testing the range you can hear, I'd suggest to contact your doctor, an ear specialist, or an medical institute where they have the correct equipment for this study.
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