The engineer claims to have successfully achieved flat impedance, flat phase loudspeakers.
I'm trying to understand the point where the magic is happening. Is it the enclosure? The cross over? Or the unity coupling amp? Or a combination?
I have a my_ref v3 amp which I believe is a current amp. Is that a correct statement?
Doesn't look like the author has much scientific knowledge... certainly not beyond that of a talented 10 year old.
I'm cautious of these blogs, because the people who often create them possess far less knowledge or credentials than they would have people believe. I understand that engineers, professors, and other professionals will dumb-down their explanations to help the layman understand the topic, but this "article" was quite poor in several respects. The blogger could stand to invest some time in an effective writing course to assist in future communication with his target group. It would be my opinion that he could also spend some time back in the classroom for other reasons, too.
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Probabley the means to the end. Interesting idea, make the crossover more complex by doubling the constraints, flat FR from the drivers and purely resistive load impedance from the speaker. Does not address a myriad of other issues.
Another question, are the distortion benefits of current drive maintained?
Had another thought, what would it take to do this for one of the popular single driver systems. I might make the trade offs clearer. I suspect there is also an efficiency hit.
You'd be probably looking at bunch of parts placed in parallel with
amp output which don't do anything to FR of the speakers. I have
read numerous times in DIY magazines tube amps could benefit
from equalized impedance. They always marked these networks
as optional, meaning solid state would not profit from it.
It's a notch filter to remove the Fs impedance hump....
(Although Joe has promised a 'White Paper' to justify it...)
How's this for a bit of prose: "...current being the native method that the motor system in dynamic loudspeakers produce sound (hence erroneous current phase angle can be modulated to produce massive amounts of phase noise, or jitter)"...
(Although Joe has promised a 'White Paper' to justify it...)How's this for a bit of prose: "...current being the native method that the motor system in dynamic loudspeakers produce sound (hence erroneous current phase angle can be modulated to produce massive amounts of phase noise, or jitter)"...
So he has a flat impedance. Whoopee! That actually is not good for SS amps. They prefer the rising impedance from the tweeter. Distortion is lower with lower current.
how flat would his box/B200 combo be without the filter? a 2-way 8" system would have limitations. I'm not sure if speaker impedance fluctuation matters much.
The problem is I'm probably pretty dumb myself. So I'm still trying to understand the following
A. Does his LS design has a merit? (How is it different from any ported design)
B. Is the magic created by the crossover OR a combination of crossover and the unity coupled amp OR the crossover + unity coupled amp + LS?
A. Does his LS design has a merit? (How is it different from any ported design)
B. Is the magic created by the crossover OR a combination of crossover and the unity coupled amp OR the crossover + unity coupled amp + LS?
B200 is in sealed box because Qt=0,75. There is no magic.
The speaker has got filter networks designed to null the
impedance peaks and other hills and valleys. You can turn
any speaker into one with flat impedance just by adding
these networks. So the "magic" is in "crossover".
The speaker has got filter networks designed to null the
impedance peaks and other hills and valleys. You can turn
any speaker into one with flat impedance just by adding
these networks. So the "magic" is in "crossover".
Greebster gave a huge hint about the author who has a 172 page thread on DIYAudio. You can read about him here:
About Joe Rasmussen
About Joe Rasmussen
The ATS-4 LRC circuits of bass section are FR shapers and they do attenuate
response. It is understandable why Troels likes to do things the way he does.
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