Hi,
Found interesting article about Jean Maurer JM 370E, 3-way speaker:
http://www.jeanmaurerhifi.ch/annexes/articles-presse/2015-04-16-hifi-jean-maurer-son-et-image-en.pdf
Crossovers are with unusual steep roolof slopes (in the order of -20 to -49 dB per octave between the bass speaker and the medium, and -38 and -70 dB per octave between the midrange and tweeter).
Anyone have idea how much amp power such passive xo "eat"?
Regards
Found interesting article about Jean Maurer JM 370E, 3-way speaker:
http://www.jeanmaurerhifi.ch/annexes/articles-presse/2015-04-16-hifi-jean-maurer-son-et-image-en.pdf
Crossovers are with unusual steep roolof slopes (in the order of -20 to -49 dB per octave between the bass speaker and the medium, and -38 and -70 dB per octave between the midrange and tweeter).
Anyone have idea how much amp power such passive xo "eat"?
Regards
Capacitors and inductors redistribute energy, they don't consume it. Resistors on the other hand do.
Simply too much of a work for me to give an accurate estimate which would have involved a complete simulation of the system. The important thing is to keep in mind that these steep filters is just another bait on a hook to catch an audiophile, offering illusion that it would have sounded better that way.
It's important to note that Capacitors and Inductors influence phase relationships in AC signals: which may be detected as "smearing" in the time domain. Larger Inductors and capacitors hold significant current which will be released as voltage across them fluctuates.
The same steep crossover setting in the digital domain does not impart this type of distortion.
This is a necessary consequence of the physics involved, and mitigating this CAN be done by designers with more patience than I possess.
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/phase.html
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The same steep crossover setting in the digital domain does not impart this type of distortion.
This is a necessary consequence of the physics involved, and mitigating this CAN be done by designers with more patience than I possess.
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/phase.html
Sent from my Nexus 6 using Tapatalk
Such rolloff slopes can be achieved -among other types- by applying parallel resonant filters around the desired crossing frequency, but the price one pays is extreme phase and impedance anomalies that present heavy load conditions for most amplifiers. It would be interesting to see the related diagrams of those speakers.. (impedance, phase, step response)
Crossovers are with unusual steep roolof slopes (in the order of -20 to -49 dB per octave between the bass speaker and the medium, and -38 and -70 dB per octave between the midrange and tweeter
Crossovers are with unusual steep roolof slopes (in the order of -20 to -49 dB per octave between the bass speaker and the medium, and -38 and -70 dB per octave between the midrange and tweeter
Thanks a lot for replies. I was curious whether such steep passive xo choke too much amp power. IMO, steeper slopes usually require more power amp. On the specs info, producer claims efficiency of 92dB, what seems to me too high.
Simulation of SB 17 NRX 35-8 and SB 26 STC C0004
in 2 different approaches. First of a less optimized shallower crossover (2nd woofer, 3rd tw) and an example of a "brickwall" type filter ( 60-70 dB/oct). With 30 W of input power and typical dcr values for LP inductors, their dissipation can reach at some frequencies a couple of watts easily.
in 2 different approaches. First of a less optimized shallower crossover (2nd woofer, 3rd tw) and an example of a "brickwall" type filter ( 60-70 dB/oct). With 30 W of input power and typical dcr values for LP inductors, their dissipation can reach at some frequencies a couple of watts easily.
Attachments
If passive xover is what you want...
Not using high electrical xover orders and by that avoiding losses requires thinking out of the box a little.
If you use, say classic 12dB/o and then use a couple of series notch filters - one very close to xover point, and others to deal with response ripples. It's been done successfully before - Joseph Audio comes to my mind
That would be one way to avoid losses 😉
Read about Richard Modafferi and his patents also.
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