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View Full Version : When to change crossovers???



bruno13
08-13-2015, 02:37 PM
Hello,
I am what's know as a diehard DIYer. I have recently changed from a 511B horn driven by an 802-8D paired up with the N-800-F (because when I first designed/built these last march 2015 I wanted to pair some 416's with a pair of 811B's driven with the infamous 802-8D's and to bring these dance partners together I used some N-800-F crossovers. But since then I've gotten rid of the 811's and went with 511's...for awhile anyway because now, I'm taking the 511's out of the cabinet, thinking there's really no need for the woofers to have to share precious space, so now after building a new baffle face plate and it's a 2-holer! That's right each cabinet will house 2- 416's, as my horns are now 1004B monsters that hang from chains attached to the ceiling, powered by some attractive 288's, now we get to the dilemma to change or not to change, that is the question... thought I would simply leave well enough alone. But now...I went from 811B's to 511B's (barely fit) to an external 1004B hanging from the ceiling on chains driven by a pair of nice 288's.
Now my question, I really need to reconsider my "leave well enough alone" statement...huh?
I have, or more correctly I'm soon to be removing the 511's from the cabinet completely (the horn/drivers are in the cabs but disconnected) and replace the baffle face with a new 2-holer!
Yes a pair of 416-8a's in each cabinet! with monstrous 1004B horns looming over my tiny (36inT X 33inW X 26inD) little cabinets...I say that jokingly because they still seem to dwarf my cabs, go big or go home, is what a friend of mine says...too often. Do I absolutely need a 500Hz crossover???? To be all that I can be?
Thank you and I truly respect opinions and constructive criticism.

more10
08-14-2015, 12:48 AM
Go active!

http://www.minidsp.com/products/opendrc-series/minisharc-kit
http://www.ackolabs.com/dac.html
http://www.twistedpearaudio.com/landing.aspx
http://sourceforge.net/projects/rephase/

Lots of integration to make it work :-)

Mårten

fpitas
08-14-2015, 08:12 AM
I would think that, because of the huge vertical separation between the woofer and horn, a lower crossover is in order.

bruno13
08-16-2015, 04:06 PM
This may sound like a stupid question, but what does the vertical separation have to do with it? I thought it was about woofer driver/size/model, horn and disbursement, etc. I'm about to embark on another re-build of the baffles to get rid of the unused 511/802's that presently occupy some of the cabinet space that will be needed for the addition of another 416. Let me back up a step, what I feel I lack is in the bass department. I would like a little bit thicker, sharper bass, and I've been under the impression that it has to do with where your crossovers cross frequency, right now in the cabs are N-800-F's and I also have a nice pair of N-800-D's but not sure the difference. It's not that I can't get more bass with for instance my equalizer, but it isn't more bass I'm looking for, it's more defined bass. I am on a HUGE learning curve right not so please forgive the ignorance.
And thank for responding.
Mike

bruno13
08-16-2015, 04:13 PM
Go active!

http://www.minidsp.com/products/opendrc-series/minisharc-kit
http://www.ackolabs.com/dac.html
http://www.twistedpearaudio.com/landing.aspx
http://sourceforge.net/projects/rephase/

Lots of integration to make it work :-)

Mårten

Hi Marten, What do you mean, I am truly close, but there's still the problem of the horns/drivers overpowering the little 416, thus the 2-holer loaded with a pair of 416's...right? I mean will that help? Oh and what do you mean, "go active"?

fpitas
08-16-2015, 04:17 PM
At the crossover frequency, the vertical dispersion will depend on the vertical separation of the horn and woofer. If they are much over one wavelength apart, the forward vertical lobe will be very narrow, and past a wavelength of separation the vertical dispersion will break up into lobes. Here's a handy little simulator that will demonstrate the situation:

http://www.tolvan.com/index.php?page=/xdir/xdir.php

(http://www.tolvan.com/index.php?page=/xdir/xdir.php)It will be easiest to start if you set the woofer phase lag to 0 degrees.

Francis

more10
08-16-2015, 04:18 PM
Oh and what do you mean, "go active"?

Active filters. Electronic filters between preamp and power amps. You will need a separate power amps for horns and woofers.

bruno13
08-29-2015, 11:15 AM
At the crossover frequency, the vertical dispersion will depend on the vertical separation of the horn and woofer. If they are much over one wavelength apart, the forward vertical lobe will be very narrow, and past a wavelength of separation the vertical dispersion will break up into lobes. Here's a handy little simulator that will demonstrate the situation:

http://www.tolvan.com/index.php?page=/xdir/xdir.php

(http://www.tolvan.com/index.php?page=/xdir/xdir.php)It will be easiest to start if you set the woofer phase lag to 0 degrees.

Francis

The Tolven Xdirector was helpful! Thank you! I've made some changes lifted the cabinets off the floor 8inches, and seen to have a very smooth arc, with parameters set at woofer phase lag -01, 500Hz, woofer dist 70mm and tweeter woofer woofer is that right? I do know this, by ear they sound wonderful at any level. The horn being directional couldn't you make up for any wave problems by simply changing the angle of disbursement in the suspended horns?
And thank you very much for the advise ahead of time!
Mike

bruno13
10-29-2015, 11:12 AM
Active filters. Electronic filters between preamp and power amps. You will need a separate power amps for horns and woofers.

Changes have been made and to my surprise for the better! I got rid of the 500Hz crossovers because when I tried the Altec N-800-D's oh my gosh, there is my bass I've been lacking! I switched the baffle out to a 2-401-149 (same as the 803 or 416) in each cabinet lifted my cabinets 8ins decreasing the separation between woofer and horn to roughly 18ins of separation now, and vertically aligned the horn and woofer magnets and wah lah!! Perfection! Here's a picture of the final product, a real labor of love!6793267931