XSim free crossover designer

Is there an option for using mm instead of inches in the 3D baffle sim?
Is there a way to save the curves scale and display choices so they don't reset?

No, sorry. I originally (some years ago) was having it work in inches or meters, but that got too complex to maintain the code. If I were starting over, I'd do it all in metric, since speaker makers are more used to that now than they (the ones in US) were in the past.

I don't know a practical way to save curves and scaling, since each plot is a separate creation (which is why you can have a dozen or so individual frequency response graphs, or other types if you want to). I guess it would be possible to save them with project file saves, but not really as universal choices.
 
If I have a finished bi-wired or tri-wired system with crossover can I use xsim to modify the responses in the same way as the original design method?
i.e. use DATS and Omnimic to measure each driver through its own separate crossover components and load the results into xsim, then experiment with additional inductors/capacitors/resistors to modify the response and impedance of the total system.
That would allow the user to build a first crossover, test and trim to get a final result.

I just now saw your question, sorry for late reply. I think the only practical way to mod a finished crossover is to model it again with measurements made on each driver without its crossover. You could do what you say, and treat each driver and its crossover filter as a unit (measure it that way) and then proceed as if that were your new driver. But you'd lose the ability to remove or change any of the values in the pre-existing network, which would be very limiting and would greatly limit what changes you could make. And of course it couldn't work at all with series crossovers!
 
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No, sorry. I originally (some years ago) was having it work in inches or meters, but that got too complex to maintain the code. If I were starting over, I'd do it all in metric, since speaker makers are more used to that now than they (the ones in US) were in the past.

I don't know a practical way to save curves and scaling, since each plot is a separate creation (which is why you can have a dozen or so individual frequency response graphs, or other types if you want to). I guess it would be possible to save them with project file saves, but not really as universal choices.

The min max frequency and vertical position could arguably be set alike for enough projects. Saving all curve params with each project will do anyway. To can continue work as last time visually set.
 
I created frd and zma data for a Volt RM3863 woofer from Volt's published curves using GraphTracer. Opening both files with Notepad confirmed the data is correct. Both load OK into Xsim but the frequency response is extended beyond the loaded data. It looks like Xsim has created an additional response curve from the cut-off at just under 5KHz. There is no data in the frd file after that cut-off.


Screenshot attached. Can anyone help?

I will be going through a similar exercise with the Volt RM4564 bass driver some L&D ahead :)
 
frd and zma files

Hi Darkmatter, I see you are in East Anglia too!

I had a shock when I used Omnimic to generate the frd and zma files. They bore no resemblance to the data created from the Volt published curves. My Omnimic data was measured with the drive units "in the box".

I persevered with these actual measurements fed into xSim and the result has been fantastic. The finished speakers produce an astonishingly realistic soundstage with good classical recordings - better than I have ever heard from commercial speakers in demos.

I fear if I had designed the crossover using the manufacturers' curves I would have ended up with a frequency response and impedance curve all over the place. Best of luck with your project - but do measure the actual drivers in situ.
 
It's pretty darned fast to draw schematics in XSim, it's just drag and drop and/or copy and paste and drawing wires, doubt that blanks like that would save any real time. But if you wanted, you could drop "Circuitblocks" onto the schematic for certain filter or attenuator subnetworks, and then right-click on them and "change block to separate parts". Probably easier to just draw, though.
 
I have a question, and if I don't ask, I'll stay dumb forever!

All the XO designs I've seen separate the power at the source to send to each driver's own circuit.

Thing is... I've been trying to find a good and simple solution for some drivers I have, I tried something and it looks a lot better than all my previous designs.

It's a woofer (actually a full range drivers, but it dies after 9kHz) and a tweeter to bring life into it.

The tweeter circuit is connected AFTER the woofer circuit.
Is it a bad thing or is it ok?
 

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Hi perceval,

Think in diy there are no rules so if its fun and sound good to you and its enviroment or purpose thats great isn't : ) that said if that phase is truth i will call it a difuse all over spectre effect and long way from any reference but is not meant as a critic if you happen like it, amplitude response comes first but we use phase to pin point stuff, for example if you hear sirene from a rescue car strenght (amplitude) help how far it is and phase help estimate the direction, at that mic position if that speaker play a sirene it should come from all over shouldn't it : )

Also bwaslo said before that he use no stardards for circuit or wire rules from the start up, he rather looks at what need attention and happens in the various graph windows when connecting stuff, he shared some of them selfmade real builds into "File/Examples", even some linear phase sytems are there .
 
Hello Byrtt,

Thanks for the answer... so, no rules in DIY, eh? cool! :)

By the way, I had the wrong files loaded. Here's with the right frd files.

And the two very different results by either splitting the source between the drivers, or mounting the circuits in series.
 

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No there is no rules if one don't want them but if we wonna improve on past then ha ha i can think of a bunch in acoustic domain to take care at after power amp probably spit out a very high quality of played recording material, now one can choose correct for predicted or in situation with reverse curves for example baffle step and diffration/room boundary reinforcement/room pressurization gain/JBL study or own prefered house curve/wife and furniture curves and etc : )

BTW the new graphs looks much more normal and effect pedal is gone, up high except few models its hard to get most woofers cooperate because phase is havoc up there and they ab fabric not engineered to be used so high, funny enough in same relation stumbled over below 5x8 incher SBA that looks over avarage hold its off axis up into high frq area but lets see at release time in below datasheet is still in proto type level claimed as a year 2018 rev 2.
 

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Hey Perceval, looks ok to me (dunno what it will look like off-axis though, might want to model that before you cut wood). Also, for the 2mH inductor, try to use air-core. Otherwise if it gets saturated while driving the woofer that might modulate the tweeter output which wouldn't be a good thing.

Also it looks like you maybe aren't using actual impedance data? Result looks suspiciously flat and those yellow exclamation marks on the schematic is trying to tell you that something is missing...
 
Hey Byrtt,
That SBA woofer looks quite nice, and 10mm Xmax! I just hate trying to rebate an oval driver into a baffle... round is so much easier!

Bill,
the tweeter has it's own impedance file and working, it is ruler flat at 8 Ohms and figured I didn't need a zma file. I have since added a zma file and it looks the same up high. I've been having trouble with the woofer zma file... XSim doesn't want to accept it. Been trying a few times... did the exact same thing as the tweeter to measure, but unlike the tweeter zma file which works fine, the woofer doesn't want to load. I'll be working on it again...
Also, in the baffle designer, offset looks ok until about 20 degrees off axis, where a dip develops at 6.5kHz.
 
...I've been having trouble with the woofer zma file... XSim doesn't want to accept it. Been trying a few times... did the exact same thing as the tweeter to measure, but unlike the tweeter zma file which works fine, the woofer doesn't want to load...

When that happens REW is often our good helping friend, ask REW to import that woofer file with the error and it would most probably tell you under load that there's a mistake in say line 1580 and also often the reason, then open zma file in a raw txt editor of some kind and edit that line and wupti XSim probably read it now, if not import once again into REW and it tells of next line with a error or if it happen open it up with no errors then simply export with REW standard settings and XSiM gets happy again.