Hi.
I've got the aluminum radian driver. Someone told me they should be crossed over around 5 or 6 k. But by that point. The radian is already dropping off rapidly ... Can't load the horn I guess.
What crossover point would you use? I'll post some sweeps next week. Cottage opening this weekend. Cheers! Oh an is it really important to have a low pass section? The 511b rolls off like crazy. I'll post a pic next week
Thanks all!
I've got the aluminum radian driver. Someone told me they should be crossed over around 5 or 6 k. But by that point. The radian is already dropping off rapidly ... Can't load the horn I guess.
What crossover point would you use? I'll post some sweeps next week. Cottage opening this weekend. Cheers! Oh an is it really important to have a low pass section? The 511b rolls off like crazy. I'll post a pic next week
Thanks all!
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Greets!
Here's a Tom Danley measurement of an old 511 combo, though the Radian does roll off early ~ like the measurement (Radian? diaphragm, TD didn't remember any details when he PM'd ages ago) whereas a fresh 802 is much flatter to 5 kHz before it 'slides' off the curve due to the 511's conical/expo throat adapter, so is better suited to using it as a (high) mid with 5 kHz the once? popular XO point and FWIW a good XO point IME to use an Altec or similar performance CD as a dedicated (super) tweeter.
FWIW, last 511B factory measurement I recall seeing.
Factory recommended using 500 Hz/2nd minimum, though as power requirements increased it went to 800, then 1000 - 1200 Hz with up to 4th order, though for HIFI/HT apps, most folks are using somewhere in between due to not willing/wanting to acoustically address its inherent ~450-900 Hz horn 'honk'. Got to have its cinema/pro sound 'look' being the main one.
Whether or not, or at which point, you use a hi-pass depends on a number of variables only known by you 😉, so best to empirically draw your own conclusions, then please tell us since we can't have too many experienced viewpoints, though personally didn't until going with a dual 802-8A, 802-8G 511 horn stack with an HP on the latter that later was swapped for a huge DIY dual driver parabolic WG to get the max LF coupling to 210 compression horns.
Here's a Tom Danley measurement of an old 511 combo, though the Radian does roll off early ~ like the measurement (Radian? diaphragm, TD didn't remember any details when he PM'd ages ago) whereas a fresh 802 is much flatter to 5 kHz before it 'slides' off the curve due to the 511's conical/expo throat adapter, so is better suited to using it as a (high) mid with 5 kHz the once? popular XO point and FWIW a good XO point IME to use an Altec or similar performance CD as a dedicated (super) tweeter.
FWIW, last 511B factory measurement I recall seeing.
Factory recommended using 500 Hz/2nd minimum, though as power requirements increased it went to 800, then 1000 - 1200 Hz with up to 4th order, though for HIFI/HT apps, most folks are using somewhere in between due to not willing/wanting to acoustically address its inherent ~450-900 Hz horn 'honk'. Got to have its cinema/pro sound 'look' being the main one.
Whether or not, or at which point, you use a hi-pass depends on a number of variables only known by you 😉, so best to empirically draw your own conclusions, then please tell us since we can't have too many experienced viewpoints, though personally didn't until going with a dual 802-8A, 802-8G 511 horn stack with an HP on the latter that later was swapped for a huge DIY dual driver parabolic WG to get the max LF coupling to 210 compression horns.
I will post a sweep when I get back to the city. I have no idea if another horn would improve the frequency response
Speaker/horn design is all about trading efficiency for BW, so the short answer is no without further definition. Also, per T/S theory the box design peters out at its tuning (Fb) on the low end and the HF at the driver's effective upper mass corner (Fhm).
Historically, compression drivers are under damped 4th order band-pass (BP) alignments whereas its horns are acoustically over-damped, so the widest BW for a given combo is when the two sum flattest; ergo any driver, horn design shift in either direction = less flattest BW.
upper: Fhm = 2*Fs/Qts'
lower: Flc = Fs*Qts'/2 [normally never used]
Qts': 2*Fs/Fhm
[Qts']: [Qts] + any added series resistance [Rs]: http://www.mh-audio.nl/Calculators/newqts.html
[Rs] = 0.5 ohm minimum for wiring, so may be higher if a super small gauge is used as a series resistor and/or there's other series resistance.
Historically, compression drivers are under damped 4th order band-pass (BP) alignments whereas its horns are acoustically over-damped, so the widest BW for a given combo is when the two sum flattest; ergo any driver, horn design shift in either direction = less flattest BW.
upper: Fhm = 2*Fs/Qts'
lower: Flc = Fs*Qts'/2 [normally never used]
Qts': 2*Fs/Fhm
[Qts']: [Qts] + any added series resistance [Rs]: http://www.mh-audio.nl/Calculators/newqts.html
[Rs] = 0.5 ohm minimum for wiring, so may be higher if a super small gauge is used as a series resistor and/or there's other series resistance.
Oh my... Lots for me to look at. I have a pair of jbl2404h tweeters, I was going to use them with a high pass at 5350hz, 24db per octave. This give readily available parts for a 4th order LR crossover assuming 8 ohms R for the tweeter. I'm not sure if that's a good assumption, or if I should lower it. Would measuring R be better? As you can see, I'm totally new at this
Well, ideally you must measure each device to find the optimal XO point/slope, but the pioneers gave us enough info to get 'close enough' for prosound apps, so often do well in (vintage) HIFI apps.
In short, the 511 horn is beginning to roll off at ~5 kHz/100 deg. horiz. and the 2404H is just beginning to flatten out, so the pioneer's standard 'textbook' 5 kHz/2nd order is the de facto default, so see no good reason to use 4th order as there's plenty of overlap for max power use at low distortion, though once in-room may want to fine tune it a little.
In short, the 511 horn is beginning to roll off at ~5 kHz/100 deg. horiz. and the 2404H is just beginning to flatten out, so the pioneer's standard 'textbook' 5 kHz/2nd order is the de facto default, so see no good reason to use 4th order as there's plenty of overlap for max power use at low distortion, though once in-room may want to fine tune it a little.
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