A simple fix for a loudspeaker problem?

Speaker Asylum

General speaker questions for audio and home theater.

I have to confess I have had to steal to be able to write this posting :( I have chosen to steal some lines from Robert E Greenâ€™s excellent homepage:
www.regonaudio.com
Anyone not familiar with his homepage should stop reading this posting now and head directly towards his homepage.
Anyway while being sick with the flue last week I did read one of his articles, actually not the most interesting of his articles, but it made my mind spin and I would like to suggest a simple solution to the problem suggested by him in the article.
The easiest way for me to present the problem is to take his words directly from the article covering the TACT Millennium amplifier and Dali Grands So now I hand you over to REGâ€™s:
â€œEveryone is familiar with the idea that drivers generate distortion when they are driven too hard. But what is much less familiar is that drivers also tend to misbehave when the signal driving them is too small. What causes these non-linearities at low levels is the tendency of mechanical systems to stick and then slip. A good example is pushing on a chair across the floor. If you push gently, the chair does not move. If you gradually increase the force, the chair will suddenly give a little jump forward, as it breaks loose from the frictional interaction with the floor. The whole process is highly non-linear.
This sort of thing is quite analogous to (undithered) digitization, where a signal below the least significant bit is ignored until there is a jump when the LSB level is reached. And as everyone knows, only high-level signals are recorded without significant distortion.
Considering how annoying the sound of undithered digital is, it is surprising that people took so long to start thinking about the effect of the mechanical "digitization" of the stick/slip phenomenon in speakers. It is this problem that the Dali designers, in a joint project with the driver manufacturer VIFA, undertook to deal with. The drivers of the Grand are tested to play cleanly at -15 dB absolute (15 dB below the midrange threshold of hearing), at a level where most drivers have lost clarity or even lost response altogether.
It is hard to be sure about the connection between this exotic experimentation (-15 dB is almost inconceivably quiet) and actual listening. But it is a fact that the Dali Grands have an exceptionally high level of perceived resolution, right in there with panel speakers. Perhaps it is the absence of the stick/slip phenomenon in, for example, electrostats that makes them have such a high level of resolution in audible terms. And here is the same thing in a dynamic.â€
Thanks to REG for presenting the problem so clearly, now I am back with my silly suggestion of how to combat the problem described by REG.
Wouldnâ€™t it be possible to eliminate this hysteresis problem, simply by playing white noise at a very low level while listening to the music? The white noise should be adjusted in level according to frequency so the driver unit just starts to move ever so slightly at all frequencies at all time.
Wouldnâ€™t his be a simple fix?
Has it ever been done/tried?
Could it explain why some prefer noisy tube/valve amps instead of perfect solid state amps?
Best wishes from Denmark
KlausDK
PS: Thanks to REG for making such stimulating reading public.

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Topic - A simple fix for a loudspeaker problem? - klausDK 03:29:21 03/30/07 (2)

Re: A simple fix for a loudspeaker problem? - chocolate_lover9999@yahoo.com 11:21:06 03/31/07 (0)

Re: A simple fix for a loudspeaker problem? - sser2 11:04:54 03/30/07 (0)

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