A friend strongly believed there is record crap at 8 Hz which must be avoided. It seems he was right, the lateral resonance must be centered on 9 Hz or higher to avoid it, otherwise sounding dull from excess resonance stimulated at 8 Hz. In most 2 axis tonearms the lateral resonance is going to be lower, hence first subjected to this issue first.
And that may be why in long tradition, I believe, excess tonearm mass is associated with "dull" sound.
And also now I have a good explanation as to how a resonance with two peaks and null in the middle can shift in seemingly non-linear ways.
Say I measure maximum resonance at 8 Hz. It could will be that some of the lower peak area is actually in 7 Hz.
Now suppose I subtract mass to raise the resonance frequency. But the 8 Hz sounds exactly (or nearly) the same !!!
What may have happened is instead of the lower mode being in a different Hz range, now the upper mode is in a different Hz range, in this example, 9 Hz. Well, then the level at 8 Hz will sound exactly the same.
When will the 8 Hz sound substantially different? Certainly as soon as the entire upper mode in in the 9 Hz range, that is with the null at exactly 9 Hz or higher.
That is what exactly seems to have been the case when I reduced the extra headshell mass from 6.1 Hz to 4.9 Hz. The 8 Hz stayed almost exactly the same, because the null merely shifted from the lower 8 Hz to the upper 8 Hz by about the same amount.
No comments:
Post a Comment