Thank you for the link to a word you have typed into an internet search engine. I repeat, in the absence of a clear statement, I will not put words in somebody else's mouth. And it is far from clear to me:
I have to ask what 'mechanical highpass "filter" ', and what 'electrical counterpart'? Assuming we lived in a universe so arranged that it is possible to have an exact equivalent in each with zero other effects whatsoever, then they would indeed sound the same. I doubt anybody would argue with that for very obvious reasons. For better or worse however, we do not live in such a universe. Ergo, a blanket, contextless statement that some kind of unspecified mechanical 'filter' or 'phenomenon' sounds exactly the same as its equally unspecified 'electrical counterpart' is nonsense. I would be delighted to be proved wrong and shown that there are such exact equivalents somewhere, but I have never seen such a thing, and it runs counter to all the engineering that I am familiar with.
I have to ask what 'mechanical highpass "filter" ', and what 'electrical counterpart'? Assuming we lived in a universe so arranged that it is possible to have an exact equivalent in each with zero other effects whatsoever, then they would indeed sound the same. I doubt anybody would argue with that for very obvious reasons. For better or worse however, we do not live in such a universe. Ergo, a blanket, contextless statement that some kind of unspecified mechanical 'filter' or 'phenomenon' sounds exactly the same as its equally unspecified 'electrical counterpart' is nonsense. I would be delighted to be proved wrong and shown that there are such exact equivalents somewhere, but I have never seen such a thing, and it runs counter to all the engineering that I am familiar with.
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These?
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dave
Seaching that turns up pretty much the same thing in black.
I have seen various similar schemes. Modern modeling is really going to help explore the possibilities.
The research i read is old but the size of the holes and the patterns will have different kinds of effects at different frequencies.
The KF are coax and you can see 3 different patterns.
Paradigm
dave
I have seen various similar schemes. Modern modeling is really going to help explore the possibilities.
The research i read is old but the size of the holes and the patterns will have different kinds of effects at different frequencies.
The KF are coax and you can see 3 different patterns.
Paradigm
dave
Hello,
you can correct the frequency response of your fullrange driver with EQ and/or DSP on axis to get a perfect time response.
As for the beaming on axis at high frequencies it works very fine to put indirect reflecting drivers at the sides of the box and/or backside or top of your speaker, depending on your room an reverberation field.
The output could even be as loud as on axis without disturbing your direct sound field as long as:
1. your indirect drivers should give no output below 5 khz
2. appropriate is a 18db filter or some tweeter which goes down at that frequency naturally
3. You should be able to regulate the tweeter with an L-Pad if necessary
4. you can enhance directivity of these indirect working tweeters by putting them deeper into the enclosure (or fixing them on the backside of a hole of your baffle)
There are Audax Tweeter copies in car hifi (famous mix of cone and dome) produced in millions which work with just one capacitor and have the desired frequency response.
Thanks for this pointer. I downloaded your linked page. I never thought of the cap shunt idea. I have been hesitant WRT ".5" systems because of the change in load impedance in a critical area of the spectrum and its effect on tube amps. Using this setup given a tube amp with 8ohm OPTs you could use two 8 ohm drivers in series thus over most of the range the impedances match and in the lowest octaves where distortion would likely be highest you get a shallower load line which actually eases the load.
Seems worth considering. As a side note theoretically one could put a power resistor in series with the cap to give it a step function so that the second woofer is not entirely shorted. Not sure if that would ever be desirable but technically possible.
Given that the 4//8/16 ohm taps are nominal. Few speakers have flat impedance. You use the tap that sounds best. As long as your amplifier does not have a sinificantly high Rout it should not be an issue. If it is an SE, they do tend to have higher Rout and you would need to worry somewhat about the frequencies where the impedance is higher might have a lift in the response. Only listening will tell you if that is an issue.
dave
dave
I've used a cap shunt in six of my speakers so far and will be using it again in a desk top speaker. Because of the rising impedance ( with frequency ) of drivers the resistance would be more than double the DC Resistance where the cap comes into play ( about 7,000 Hz ). I've also wired speakers in parallel with the rear facing driver having a choke in series, however I intend on experimenting with a contour network on the front facing driver.