audiosteve, let me explain it to you.
Only two things matter in the audio game.
The FRD and the ZMA file.
This is what simulators use. Certain complexities about baffle size and measurement, but I know this stuff.
https://www.visaton.de/en/literature-software/software
Of course I am talking about flattening the impedance.
Only two things matter in the audio game.
The FRD and the ZMA file.
This is what simulators use. Certain complexities about baffle size and measurement, but I know this stuff.
https://www.visaton.de/en/literature-software/software
Of course I am talking about flattening the impedance.
That's a good looking program. I've always used CALSOD and IMP in the past with good results. I'll give BoxSim a try. Thanks.
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I've tried emailing rhythmaudio for the slapshot crossover, offering money, no answer.
On parts express forum, i was told (new 6 months ago ?) owner was out of the country.
I couldn't even buy the slapshot, i was ready to also.
I tried just now, you can put stuff in the cart, but hit checkout, and it says "this store isnt taking orders now".
Been that way for months.
Seeing morel's roll off with recommended 5.6uf, having it run that way with an eminence b102 (run wide open), then having the eminence/morel cranked through a good onkyo reveiver crossed at 200hz, as loud as the 80+ watt receiver would go, i don't think it needs a trap for the Fs.
It is aready rolling off just fine without it.
But, i could be wrong,
I am no crossover guru.
But,
i'd like to see measurements with/without notch with the 5.6uf recomended cap.
On parts express forum, i was told (new 6 months ago ?) owner was out of the country.
I couldn't even buy the slapshot, i was ready to also.
I tried just now, you can put stuff in the cart, but hit checkout, and it says "this store isnt taking orders now".
Been that way for months.
Seeing morel's roll off with recommended 5.6uf, having it run that way with an eminence b102 (run wide open), then having the eminence/morel cranked through a good onkyo reveiver crossed at 200hz, as loud as the 80+ watt receiver would go, i don't think it needs a trap for the Fs.
It is aready rolling off just fine without it.
But, i could be wrong,
I am no crossover guru.
But,
i'd like to see measurements with/without notch with the 5.6uf recomended cap.
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Based on simulation with traced graphs (not an actual measurement) the following is:
1. CAT378 raw response
2. with 5.6 uF cap
3. with 5.6 uF cap and LCR impedance peak EQ (1.1mH+39uF+10R)
4. as (3) plus CR Zobel linearization (1.8uF + 11R)
The target is a HP LR3 @2300 Hz, as it matches (3), and is the same on all graphs.
1. CAT378 raw response
2. with 5.6 uF cap
3. with 5.6 uF cap and LCR impedance peak EQ (1.1mH+39uF+10R)
4. as (3) plus CR Zobel linearization (1.8uF + 11R)
The target is a HP LR3 @2300 Hz, as it matches (3), and is the same on all graphs.
Attachments
I calculated the LCR conjugate at 1mH + 47uF + 10R. My methods are rough and ready, back of a beermat stuff sometimes.
But top marks to Draki for his sims. I would question if such a thing as LR3 really exists. But will let it go here. Never crossed my mind to use a Zobel.
Mike Chua got something in the same ballpark.
But top marks to Draki for his sims. I would question if such a thing as LR3 really exists. But will let it go here. Never crossed my mind to use a Zobel.
Mike Chua got something in the same ballpark.
Cat378 + 5.6uf, I would call it initially a 6db crossover.
Bob brines thought -6db at crossover, -12db an octave away would be enough for 6db time/phase aligned.
I know i don't shut up about it, but i see -6db at 2khz then -15db (almost -12db) at 1khz.
I'd call it close enough for a 6db time/phase aligned.
I've wanted to make a 6db mtm using the cat378.
Like dunlavy, i assume at least 10' listening distance, especially if using 6.5's.
The 8" 4ohm sb acoustics seems a close match in spl.
But some like to cross an 8" at 1khz if 6db (or steeper).
I used to think 8", 2khz, set it and forget it.
Sitting 15', i am more aware of dispersion issues, so a 6db 8" 2khz may be a bit 800+ hertz lacking far field.
I prefered a 6.5" silver flute crossed at 2khz over the 4ohm 8", from a midrange clarity point of view.
But that was with the weeny dayton horn dome, sounded good, for a wimpy 6" 2-way anyway, lol.
Bob brines thought -6db at crossover, -12db an octave away would be enough for 6db time/phase aligned.
I know i don't shut up about it, but i see -6db at 2khz then -15db (almost -12db) at 1khz.
I'd call it close enough for a 6db time/phase aligned.
I've wanted to make a 6db mtm using the cat378.
Like dunlavy, i assume at least 10' listening distance, especially if using 6.5's.
The 8" 4ohm sb acoustics seems a close match in spl.
But some like to cross an 8" at 1khz if 6db (or steeper).
I used to think 8", 2khz, set it and forget it.
Sitting 15', i am more aware of dispersion issues, so a 6db 8" 2khz may be a bit 800+ hertz lacking far field.
I prefered a 6.5" silver flute crossed at 2khz over the 4ohm 8", from a midrange clarity point of view.
But that was with the weeny dayton horn dome, sounded good, for a wimpy 6" 2-way anyway, lol.
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The final designed slope of a driver is a sum of its' inherent HP (or LP, or BP) slope plus whatever electrically added = acoustic slope.
This makes a realistic 6 dB acoustical slope very rare. For more elaborate information, see this white paper from KEF (pages 31 thru 36).
https://us.kef.com/pub/media/wysiwyg/documents/thereference/REF_White_Paper_preview_path_200514.pdf
The CAT378 discussed here has a raw response which resembles apx 1100 Hz LR2 HP slope (disregard the 2 to 6 KHz bump due to the waveguide loading).
This makes a realistic 6 dB acoustical slope very rare. For more elaborate information, see this white paper from KEF (pages 31 thru 36).
https://us.kef.com/pub/media/wysiwyg/documents/thereference/REF_White_Paper_preview_path_200514.pdf
The CAT378 discussed here has a raw response which resembles apx 1100 Hz LR2 HP slope (disregard the 2 to 6 KHz bump due to the waveguide loading).
Attachments
I don't find that to be a problem; it seems about the same in that respect as the Vifa BC25s used in my other projects. I really like the way the CAT reproduces violins and cymbals.I have used them and they are great. However, the beaming/directional behaviour was annoying and was a little more strong than the datasheet shows. Low distortion classy driver though. They certainly gave me a little taste of horn
However, I won't be using them again as the price has gone into the stratosphere.
Geoff
I thought the same thing, but found out it does exist. Unfortunately a LR3 will have a -3 dB dip at the crossover point. This graphic is from the book : "The Design of Active Crossovers" by Douglas Self.
