To validate take the enclosure and lay it on its side in your driveway and place the mic 2 metres from the enclosure baffle.
Then measure again. This is referred to as a ground plane measurement and is a lot more reliable for measurements of the actual loudspeaker below 300 hertz.
If that is not convenient lay the enclosure on its back and take measurement 1 metre above on axis with the tweeter. This will remove most of the room reflections at lower frequencies.
With measurements if the data is not reliable your limited with their true value.
I never measure my JBL studio monitor projects inside.
In this scenario your full range drivers most likely have limited Xmax (linear peak to peak excursion in the BL range). What this means is the full range driver probably wont have a lot of power handling below 100 hertz. So deliberately limiting the voltage drive at low frequencies will reduce distortion and improve displacement limited output of the full range driver.
Finding the optimum roll off frequency and slope will take some trial and error.
If the full range driver enclosure is sealed its natural response will be 12 db per octave assuming a Q of 0.707. If its a bass reflex enclosure the natural response will be either 18 db (QB3) or 24 db (BB4). Below that your driver is unloaded. So try and shoot for a crossover point one octave above the tuning frequency Fb to start with. For example with a Fb of 45 hertz try a 90 hertz crossover point using a 24db slope on the high pass and low pass. Crossover points below 80 hertz or so can invite group delay in the woofer and so you will need to experiment with the placement of the sub forward and aft of the full range enclosure for the best integration. You may find a 100 hertz or 150 hertz crossover point preferably depending on the size of the full range driver.
If you buy a Dayton DSP subwoofer plate amp it has a App with DSP to assist in sorting out all the room interaction and main loudspeaker integration issues.
Good luck with your project.
I measured my full ranges a few weeks ago, and they seem to follow a 12db slope from somewhere between 80z and 120Hz. As I'll have stereo subwoofers, I'll be experimenting with an xover point between 120 and 160, but probably with an 18 or 24db slope.
Great. Let us know how it goes.
Biamp crossover kits aren’t new by any means and it takes a bit of time to figure it all out!
I attempted my first Biamp project back in the mid 1970’s with an 8 inch two way Magnavox 8-30 system (Etone 30 watt woofer and Philips 25 mm dome tweeter) crossing over to a 15 inch Jbl 2231A woofer at about 150 hertz using a Subtractive Active Crossover. As l recall it was a kit from Electronics Australia or ETI magazine. The Magnavox 2 way system took on a new lease of life. With these learnings in 1979 l built a clone of the famous Jbl 4343 monitor with some guidance from Gary Margulius at JBL and biamped it with a Nakamichi black box active crossover using a Quad 405 and Phase Linear 700B. At the time it was an impressive system.
You learn as you go and every project brings something new.
Of course back then there was no internet and you either bought a text book to understand crossover theory, research it at the Uni library or read about it in an electronics hobby magazine.
So you guys have got it easy....LoL.
Biamp crossover kits aren’t new by any means and it takes a bit of time to figure it all out!
I attempted my first Biamp project back in the mid 1970’s with an 8 inch two way Magnavox 8-30 system (Etone 30 watt woofer and Philips 25 mm dome tweeter) crossing over to a 15 inch Jbl 2231A woofer at about 150 hertz using a Subtractive Active Crossover. As l recall it was a kit from Electronics Australia or ETI magazine. The Magnavox 2 way system took on a new lease of life. With these learnings in 1979 l built a clone of the famous Jbl 4343 monitor with some guidance from Gary Margulius at JBL and biamped it with a Nakamichi black box active crossover using a Quad 405 and Phase Linear 700B. At the time it was an impressive system.
You learn as you go and every project brings something new.
Of course back then there was no internet and you either bought a text book to understand crossover theory, research it at the Uni library or read about it in an electronics hobby magazine.
So you guys have got it easy....LoL.
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Can anyone help. I can not figure out the values I need to add to the kit, I can build the kit with no problems but I can not understand how to choose values for C and R. I have used the calculator and came up with some numbers. The R are pots so I do not touch them. I think I have to choose C. Would you please let me know, what should be the values for C for 2nd and 3rd order 1200hz, 1600hz and 18000hz values, for hipass and lowpass.
Thanks a lot! So it is very simple, just divide 6000 for 2nd order and 7000 for third order. Great.
Here is my summed response with minidsp with asymmetrical filters of 2nd order 1200 for mids and 3rd order 1600hz for tweeter. You can also see phase response. This will be a starting point for me, what do you think should be measuring better, which parts should be bettered?
Here is my summed response with minidsp with asymmetrical filters of 2nd order 1200 for mids and 3rd order 1600hz for tweeter. You can also see phase response. This will be a starting point for me, what do you think should be measuring better, which parts should be bettered?
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I'm at a loss on how to get a Nelson Pass crossover and I've been trying since February. +
I emailed Pass Labs and Kent English got back to me quickly but XVRs are out of production. It was a nice email. I emailed RenoHifi and Mark responded quickly but they don't have any. There was an XVR-1 on usaudiomart but that sold quickly before I saw it. Months ago I requested email notification from DIYaudiostore for when LXMini boards came in but no notification materialized.
Finally I stumbled across this thread and got my hopes up again. I emailed and voicemailed DIYstore yesterday, no reply so far. Each day the feeling gets heavier that I missed my chance
So my question is how does an average enthusiast purchase a 6-24 crossover?
I emailed Pass Labs and Kent English got back to me quickly but XVRs are out of production. It was a nice email. I emailed RenoHifi and Mark responded quickly but they don't have any. There was an XVR-1 on usaudiomart but that sold quickly before I saw it. Months ago I requested email notification from DIYaudiostore for when LXMini boards came in but no notification materialized.
Finally I stumbled across this thread and got my hopes up again. I emailed and voicemailed DIYstore yesterday, no reply so far. Each day the feeling gets heavier that I missed my chance
So my question is how does an average enthusiast purchase a 6-24 crossover?
First...this is a great crossover...better than my other line level crossovers
The DIYAUDIO store comes in and out of stock on many items. I think I saw where Nelson recently said that he just shipped a bunch of 6-24 kits to the store.
So I would be patient...at the store, when clicking on the kit...click again where it asks if you would like to be informed when back in stock, and you will get an email when the kits are available.
The DIYAUDIO store comes in and out of stock on many items. I think I saw where Nelson recently said that he just shipped a bunch of 6-24 kits to the store.
So I would be patient...at the store, when clicking on the kit...click again where it asks if you would like to be informed when back in stock, and you will get an email when the kits are available.
I saw that post but I was worried that I missed out alreadyI have an XVR1 that I bought from Reno a year or so ago. If you are interested contact me through the private message feature.
Alan
Alan
Trimpots have to be 22500 ohm or 22500 less 10k (res in series value). Thanks
What is the difference between this crossover and the AGN Basic Kit I just biught?
Analog Crossover Network: Basic Kit – diyAudio Store
Should I return it and buy this crossover instead? (I see 8 more JFETs.)
I want to drive my woofer with a solid state amp while driving the rest (mids and highs) with a tube amp (the crossover between mids and highs is in the speakers).
I am new to this - PLEASE HELP!!!
Analog Crossover Network: Basic Kit – diyAudio Store
Should I return it and buy this crossover instead? (I see 8 more JFETs.)
I want to drive my woofer with a solid state amp while driving the rest (mids and highs) with a tube amp (the crossover between mids and highs is in the speakers).
I am new to this - PLEASE HELP!!!