Yes T2030 are, but other tweeters also did not profit from the current drive. T2030 is just the only speaker driver I have "free" and I can use it for the experiment. It was driven directly, no cross-over, and was placed on a rectangular baffle 30 x 45 cm, about 10cm left and top from baffle center.
BTW, don't forget, my prediction is only for the woofer in open air, driven with 40 hz and 1 volt IIRC, which is below the free air resonance of 64.5 hz.
Once it's in a cabinet, the assumption is that the data will be significantly different, especially if it's a sealed box.
I have made this prediction, as this is how I run.... A model is of no use if it cannot predict, and I have no problem putting myself out there.
If Demian does the same data set on the sealed, I can do another prediction.
jn
Once it's in a cabinet, the assumption is that the data will be significantly different, especially if it's a sealed box.
I have made this prediction, as this is how I run.... A model is of no use if it cannot predict, and I have no problem putting myself out there.
If Demian does the same data set on the sealed, I can do another prediction.
jn
Here are some of my voltage/current comparison results - measured with a non-distorting microphone, which is essential. The tweeter benefits the least but still benefits. The 3 samples have an aluminum VC former, which according to my observations limits the current-drive distortion reduction to about 15 dB. With non-conductive formers (that is, without their eddy current distortion, that is not curable by current drive), over 30 dB drops are commonplace in third harmonic and odd-order IM products.PMA said:
Have you tested any speakers with shorting rings? With a non conductive former, you should be able to see the modulation of the eddy drag as the vc is behind center position. That would require a current drive of course, as Le(x) would be a confounder.
Have you been following the discussion of my pickup coil feedback design?
jn
ps. The page you linked to, your criticism of Klippel's analysis might be due to him using absolute levels of distortion products instead of relative. Your use of f1/f2 in the paragraph is quite confusing if it is the first thing read (which I did). Only after reading your 7 inch page and midrange page was f1/f2/fs made clear relative to each other.
Last edited:
I don't know why the contention over one set of measurements on one speaker. We all knew from the beginning that current drive works better on some speakers than others. Clearly any single speaker could be perceived to justify or dismiss the merit of current drive but it would be entirely futile.
Surely we can move past "is current drive better?" to "where is current drive useful?".
Surely we can move past "is current drive better?" to "where is current drive useful?".
Right, I have overlooked speaker position. For current drive, I have a circuit with gain, with a FB divider. He shows unity (voltage) gain behind speaker, at the FB point of the sensing resistor..
Last edited:
- Status
- Not open for further replies.