I might be able to help on this
From the graph it looks like 2500Hz on -14db start on crossover so 1 octave would be 5000Hz.
At 5000Hz it's at -28db so 14db per octave.
Take into account the frequency of the woofer at 5kHz without crossover.
The woofer probably has a spike in sensitivity in the higher order frequencies.
From the graph it looks like 2500Hz on -14db start on crossover so 1 octave would be 5000Hz.
At 5000Hz it's at -28db so 14db per octave.
Take into account the frequency of the woofer at 5kHz without crossover.
The woofer probably has a spike in sensitivity in the higher order frequencies.
It looks like -26db at 5000Hz to me (sorry for being pedantic)
So assuming I am right (2nd order acoustic on woofer and first order on tweeter) - Hows that supposed to effect the sound/phase etc ?
Would I be better off trying to change the tweeter to second order, to match the woofer ? Does anyone care ? Are people put off helping because of my user name (fatmarley) ? Perhaps I smell ? Are you supposed to leave a gap between the last letter in a sentence and the question mark ? Am I drunk or just a bit silly/tired/bored ? So many questions and so few answers...
So assuming I am right (2nd order acoustic on woofer and first order on tweeter) - Hows that supposed to effect the sound/phase etc ?
Would I be better off trying to change the tweeter to second order, to match the woofer ? Does anyone care ? Are people put off helping because of my user name (fatmarley) ? Perhaps I smell ? Are you supposed to leave a gap between the last letter in a sentence and the question mark ? Am I drunk or just a bit silly/tired/bored ? So many questions and so few answers...
Looks like 1st order electrical on the tweeter. Notice the -12dB from 6K down to 1.5K (2 octaves where the tweeter is probably naturally closer to flat), then it turns steeper when the natural rolloff of the tweeter kicks in, increasing the rolloff to something like 12dB/octave accoustic.
The woofer appears to me to be on either a 2nd or 3rd order electrical, I would have to see the response of the woofer without the network in place to know for sure.
Either way it looks like a well thought out x-over for the drivers. Measurement confirms the BSC is close to ideal.
The woofer appears to me to be on either a 2nd or 3rd order electrical, I would have to see the response of the woofer without the network in place to know for sure.
Either way it looks like a well thought out x-over for the drivers. Measurement confirms the BSC is close to ideal.
I don't know LSPCAD, but I'm sure it should be able to do this:
Select a crossover target curve. There'll all sorts of options: type; crossover frequency; slope; Q; etc. Try a few and see which matches what you've got. Start with the standard types (Butterworth, Bessel, Linkwitz-Riley, etc.). Easiest would be to identify the slope or closest slope. Then tweak the crossover frequency to bring it closer to your own. Then play with the types to find which transition area (i.e., the area between flat and the slope) matches yours. If, after this, you don't yet have a perfect match, it means that your crossover is not one of the standard types, and you may then have to use a custom option to get the target to match your crossover. But in this case it becomes a more complex description (as opposed to, say, 2nd order Butterworth).
Here's the data sheet for the woofer.
Data sheet for tweter here.
I'm using the tweeter with the waveguide.
I've tried loads of different crossovers and this one sounds best to my ears. The only problem is it's a little rough sounding when you crank the volume up on rock music.
I the problem could be a number of things. I did the Troels tweeter mods (scroll down to the bottom) to the tweeter. I have some standrd tweeters that I'll have to try.
The other thing I think it could be is break-up from the woofer. I only have a coil on the woofer and i'm using it's natural roll-off. Perhaps it's distorting here? (no question mark gap). The woofer is obviously going to be beaming at higher frequencies, so perhaps that's part of the problem? I can't say I can notice the beaming though.
These woofers have a very limited xmax (2mm IIRC) perhaps the woofers are distorting because or that?
I'm using an AR-SXO but with a cap on the tweeter.
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That's good to know. I came up with that crossover through trial and error (and a bit of measuring).
I don't think you can do that in LspCAD. It's quite a basic program with a shallow learning curve (that's why I bought it)
I have been tempted to download Holmimpulse. JustMLS (comes free with lspCAD) seems ok to me, but i'm interested to know if Holm would be better in some way.
Without knowing the series crossover values, or much at all really, it's a bit hard to comment, but 4kHz seems a bit high for an 8" paper bass to be working at. Can't you get it down a bit? Say 2.5kHz?
Parts Express: Project Showcase
Might help.
Parts Express: Project Showcase
Might help.
See the LspCAD example here Sample design . Images show a raw driver measurement, a target curve, and the curve including crossover.
Without knowing the series crossover values, or much at all really, it's a bit hard to comment, but 4kHz seems a bit high for an 8" paper bass to be working at. Can't you get it down a bit? Say 2.5kHz?
Parts Express: Project Showcase
Might help.
Here's the crossover:
See the LspCAD example here Sample design . Images show a raw driver measurement, a target curve, and the curve including crossover.
Thanks for that Shaun. I'll have a good look at that when i've got time
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