I repaired 2 amps from a jbl 7 series monitors. Trying to use them in my first higher end build of diy active monitors. I was looking to use the Dayton audio esoteric 7in woofer. Put all the data into winisd and playing with the box size and port. Got everything dialed in until I got to cone excursion, it's way off the charts. Can't figure out how to get it down. Only way I can get it below the xmax of this speaker is to set the input wattage to 10w. Changing box size and port values don't seem to do a lot for the cone excursion. I feel like I must be doing something wrong.
Why the use of those amplifiers? If the DSP settings cannot be excluded or modified, the amp Is rather useless.
The power of loudspeakers Is strange, isn't It? probably most of home midwoofers would show the same behaviour.
The power of loudspeakers Is strange, isn't It? probably most of home midwoofers would show the same behaviour.
I think we have all the possibilities here: closed box, lower power, high pass filter, and … more woofers.
The dsp can be customized either in the interface on the amp or via HiQnet which is the real reason I was after these amps. I have other devices using HiQnet and wanted to have some monitors on the same network.
I tried a few other 7in woofers in winisd and got a similar problem so I was assuming it was something I screwed up in my enclosure or port design.
I'd focus the choice on Pro drivers if heat management Is what's you're after.
A subwoofer Is the next thing to examine.
Iron Law' leaves no choices
A subwoofer Is the next thing to examine.
Iron Law' leaves no choices
There might be some software for soft saturation as well (or code it yourself?). One approach from a theoretical POV is to split the signal with a 1st order filter, soft-saturate bass only, and then combine the signals back together. There are probably more sophisticated methods, but that's the basic idea.
What you want to achieve with that is a slight reduction of bass peaks outside of the healthy range by flattening the tops with some low harmonics, and leaving a little headroom for the high frequencies to be added back in. Otherwise, if the signal is FR when it gets over-driven, there will be far more harmonics, and IMD will destroy the sound quality.
What you want to achieve with that is a slight reduction of bass peaks outside of the healthy range by flattening the tops with some low harmonics, and leaving a little headroom for the high frequencies to be added back in. Otherwise, if the signal is FR when it gets over-driven, there will be far more harmonics, and IMD will destroy the sound quality.
Ps: you'd have to calibrate the gain to the system, making it a de-facto active speaker. The soft saturation as described above should only be done after all of the volume control has been done, and the amplifier provides the speaker with fixed gain levels.
Cone excursion in WinISD is very different to music signals in the real world. I've built heaps of speakers where cone excursion is high in the software but not a problem in actual use.
Yeah, high pass filter most effective, add mo and big cone woofers for more SPL capability.
Low frequencies are ruthless, for background listening small drivers seem to work but if you want to listen at reference level ~80db full bandwidth say ~30Hz and up with ~15db headroom 3 meters away with impressive sound, simplifying room peaks and dips away, look for >12" woofers or equivalent cone area with multiple smaller woofers. Its serious business to get output down there. Some modern woofers can do rather low distortion with high excursion, so perhaps one of those, but they are very expensive.
Volume displacement is required for some SPL, which means huge excursion at low frequencies if cone area is small. Conversely, excursion goes down as you increase cone area. Or high pass the lows, or are fine with no SPL capability. Its always a compromise between size, bandwidth and SPL capability. If volume displacement is not there all you hear is harmonic distortion no matter what the marketing talk says, there is no real low end without the volume displacement.
Low frequencies are ruthless, for background listening small drivers seem to work but if you want to listen at reference level ~80db full bandwidth say ~30Hz and up with ~15db headroom 3 meters away with impressive sound, simplifying room peaks and dips away, look for >12" woofers or equivalent cone area with multiple smaller woofers. Its serious business to get output down there. Some modern woofers can do rather low distortion with high excursion, so perhaps one of those, but they are very expensive.
Volume displacement is required for some SPL, which means huge excursion at low frequencies if cone area is small. Conversely, excursion goes down as you increase cone area. Or high pass the lows, or are fine with no SPL capability. Its always a compromise between size, bandwidth and SPL capability. If volume displacement is not there all you hear is harmonic distortion no matter what the marketing talk says, there is no real low end without the volume displacement.
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I have two guesses: If excursion seems insane at reasonable power levels (especially if it's both above and below the port tuning), I bet you're modelling with positive eq / linkwitz transform / etc turned on (which can represent additional power above and beyond what you've set as the input power*). Does excursion look okay with all filters turned off?
If excursion is fine above tuning, but exceeds it below, that's fairly normal and just the way ported enclosures work. Either use a highpass to remove the possibility, or just be careful with it / let it flap as many people seem to do.
* For example; 10w in the input power and +3db eq means you are actually modelling 20w, not 10. For a single band eq it is easy to compensate; just add a static gain of the same magnitude, but negative.
If excursion is fine above tuning, but exceeds it below, that's fairly normal and just the way ported enclosures work. Either use a highpass to remove the possibility, or just be careful with it / let it flap as many people seem to do.
* For example; 10w in the input power and +3db eq means you are actually modelling 20w, not 10. For a single band eq it is easy to compensate; just add a static gain of the same magnitude, but negative.
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