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Multi-Way Conventional loudspeakers with crossovers

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Old 2nd October 2002, 02:47 AM   #11
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Default 6dB/oct lowpass filter

Grey are you refering to a rising high frenquency response on the RD75 drivers or the Neo drivers? Isn't a capacitor in series with a driver a high pass filter. Wouldn't an inductor in series be a low pass filter. Sorry for the confusion but I am sort of new to speaker design.

Thanks,

Al
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Old 3rd October 2002, 01:06 AM   #12
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Frank,
The RD-75s are quite flat from ca. 150Hz to about 12kHz or so (I'm quoting from memory). The high end rolls off of its own accord; the low end is excursion limited. If you're willing to listen at low volumes, you can run the RD series drivers somewhat lower. Note that Genesis used the RD-75 in the 1.1 down to (I think) 70Hz, and that in a speaker that played at thunderous volumes. I don't push mine that hard. My comments about fequency tailoring were directed towards calming the rising response on the Neo.
You're quite right about the lowpass filter. I should have said either series inductor or parallel cap.
Silly me.

Grey
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Old 3rd October 2002, 01:10 AM   #13
Variac is offline Variac  United States
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See Guys, I told you Grey knew about this.

Maybe someday he will tell us how he was abducted by the Krell.
Anyway , it's great to have your friendly advice again on your return to Earth
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Old 3rd October 2002, 02:32 PM   #14
diypole is offline diypole  United States
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Just got a couple monday. Will be actively crossing them at ~4-600hz to 10" peerless CSX on a dipole main panel that will be crossed at~ 80-150hz to a pair of W baffle dipole subs I have built- http://www.linkwitzlab.com/woofer.htm
Last night I simply taped them slightly off center in 2 circular peices of cardboard left from the last 12" drivers I mounted in a test baffle. I didn't futz with the 10" csx(yet), but crossed them at 200 hz directly to the dipole subs, hung them from the ceiling and just did some listening. The only equalization I did was to pop them up 3db at 150hz. My first impression was not great, but as I listened and things warmed up, I realized that these were the most solidly centered, cohesive vocals I have ever heard. I could hear the slightest breath that Cheryl Crow took, and did not miss a tweeter at all (I love live recordings, which don't contain much info over the reach of the neo8's high end).
After throwing on some live George thoroughgood, I was shocked to find the image firmly BEHIND the speakers, with great depth. I could hear someone whistling to the left of me in the audience with a palpable sense of air, and for the first time ever I was able to discern a stadium reflection when George ended a line with a "s". There appears to be some cross talk cancellation going on with these little dipole panels, because I am hearing things BEYOND the the physical width of the speakers. I am very happy for the price, even though I understand they make them in the Phillipines for a few bucks each.
Also, it was a very strange experience to stand at the side of the setup and look at panels with drivers no deeper than the cardboard throwing such a huge sound stage. I could not detect highs "sitting" on the speakers, which was one of my concerns. This was a nearfeild test. I beleive I will by two more, and stack two per side to give higher power handling, and increase soundstage height. My brother plays drums, and this 2 way dipole setup gave the most realistic kick drum(which IS a dipole) I have ever heard also, even though I'm sure there must have been a hole in the mid-bass.
regards,
Jason
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Old 4th October 2002, 03:09 PM   #15
diypole is offline diypole  United States
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Has anyone used these? What slopes/points did you settle on and what were you crossing to? ANY opinions appreciated
Jason
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Old 4th October 2002, 05:56 PM   #16
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I built a line array using 8x Neo8 per side la Alpha LS. I hi-passed them at 1500Hz using a Marchand active crossover. They are driven by two Halo SPM25 monoblock tube amps. For the midbass, the Peerless 6.5 HDS midbass (10 per side) is bandpassed between 50Hz and 1500Hz. Two Marchand MB201 amps drive them. The Neo8 are very transparent. They don't have any signature of there own. They just let the music flow. Very natural and only limited by the electronics. The soundstage is so wide, sometime I feel like I got rear speakers playing! I truely recommend these drivers.

Setup: Source: Arcam 9Se Bentaudio TX102 passive preamp
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Old 4th October 2002, 06:01 PM   #17
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Oups! Can't attach a photo.
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Old 4th October 2002, 07:15 PM   #18
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Here it is:
Attached Images
File Type: jpg dscn0115b.jpg (75.0 KB, 3056 views)
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Old 4th October 2002, 07:18 PM   #19
BrianGT is offline BrianGT  United States
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How tall are those things? They look huge! What kind of wood/veneer did you use? Do you have any construction pics? Quite interesting looking. Nice!

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Brian
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Old 4th October 2002, 07:18 PM   #20
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Very nice, they look great!
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