3way XO help greatly appreciated!

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Agree, with internet it should present no problem getting TB drivers - though I dont know how postage work in your place,
though I think that you "aussies" are known to do what ever it takes to get there, no matter the difficulties.... am I right 😉

As to different bass performance of Seas M12 and M15 - it could be the higher Qt of M12 that does the differense
 
Hi all,
Grant, just in case you want to take that big step, since you never asked for the CLR components, HERE IT GOES.:hot:
Best Regards to all,
Inductor
 

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Hi Grant...................I'm still here...Seems I'm lurking these days...........Inductors don't measure satisfactorily. All other parts I am extremely happy with................I need to deal with the inductor problem........With all the time we've spent modelling these crossovers, I am not gonna shortchange our efforts...........Iron cores for the woofer and midbass are measuring differing values which I find unacceptable. They also deviate .5 to 1mH the required values per our simulations..........So.....Back to the drawing board on that one........lol...............You seem to be having TONS of fun here lately................cool................I'll be in touch................Respectfully.............Omni
 
Hi Sreten,
I wish I had the capability of doing FRC simulations for the MCA12. It does seem a very good driver and suitable to match the P25, as you suggest. But there has been a lengthy delay already. Preferably sooner than later I need to choose the mid based on what I think will give the best outcome, ...for me ( ie, an ability to simulate).
The only data files I have to go by, specific for my boxes, are the MCA15 ones Curt kindly provided. Maybe the last xo I posted has a little merit hopefully, as a starting point. At least for the MCA15, I have files to work with, but with the MCA12 , I'd be restricted to tweaking only, which for me is not an option. So, perhaps to your chagrin (and Tinitus , Pit) unless I can buy XL very soon, I'll stick with the MCA15, and accept the consequences. If the result is terrible, then I can try to build a PMS clone, using the same drivers. thanks, grant
 
Hi Tinitus and Pit,
I looked on the TB site for interest, but there is no W3-872SC listed? I'm eager to learn new things of course, but I don't recall who 'Dave' is? As knowledgeable as he may be. I'm sure TB drivers are great, just like some value for money Dayton, SilverFlute etc. The Seas Prestige I believe are also very good, readily available and affordable.

I don't want to have 'my head in the sand' , but my idea is to copy a well respected designer, Troels, whose documentation is generally excellent, and try to use the data files provided to me by Curt. The last xo I posted looks good to me as a starting point. At least this way I have something to work with. Using 'unknown' drivers, I wouldn't have a clue where to start! Your advice is still however , very much appreciated.

Sreten of course, Omni, Curt, and now Inductor have also helped me greatly so far! Thanks guys! These are very compelling reasons to use my chosen Seas drivers. And in the event of an unpleasant result, I still have a back-up plan. It just seems sensible to me. best regards, grant
 
Hi Inductor,
I got 'caught up' with other things and until now didn't have a chance to simulate your xo in 'SW'. Thanks for providing the circuit and values. As in my last xo I posted, I used the same 'Curt' files and Z-offsets. For yours, I specified DCR's of 0.3 ohms for woofer coil, 0.4 ohms for mid coils and 0.2 ohms for tweeter coil. The tweeter 'suck-out' response looks like it needs to be inverted? The SW graphs are attached, thanks, grant
 

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Hi Omni,
Oh no! I'm so sorry to hear about the wrong value coils being supplied. I guess, right now, they are being shipped back in return for the proper values? Even if the values are higher, you shouldn't have to unwind them! Would a +- 5% deviation be acceptable, I guess? But, 1mH is a huge difference, I truly hope the outcome is satisfactory!
I know you'll sort it out quickly. best wishes mate, grant
 
Tinitus,
Its great to have your input here! Like you, I am open to new ideas, but I do need to make a 'mid' decision! I'm still going for Seas - the MCA15RCY is winning over the MCA12RC ONLY because I have some specific files to simulate right now. If I could use the 'FRConsortium Tools' , then,...I might use another driver, maybe? I'll have a look at the new TB mid anyway, thanks. grant
 
Pit, are you still about? ......this relates to your post #560 on page 56.
Yeah, I'm sure Dave (Planet 10) is a great and knowledgable guy, and I HAD been reading up on Fostex FR drivers, specifically the FE126/7e's - just for fun. Have you used these drivers? The 126 seems to have
a huge peak at about 7kHz, see Troels G's FE126/Fountek design: http://www.troelsgravesen.dk/FE126E.htm
Also please see:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=94198&perpage=10&highlight=&pagenumber=1
MarkMcK says this in post #4: quote " Fostex drivers are not good candidates for diy projects. Too many problems and too much skill required to implement them". Dave's reply didn't seem overly convincing to me, because why should I have to modify a problematic driver and ship it over here?...It makes no sense...grant
 
seems like I'm the last one here! lol, .... oh well....

Inductor,
if you're still about, would you like me to email the files that Curt sent me? Just for interest....

Omni,
Did your new coils arrive, and any xo results as yet? I'd love to know!

thanks everyone....
 
I specified DCR's of 0.3 ohms for woofer coil, 0.4 ohms for mid coils and 0.2 ohms for tweeter coil
it's fine grant.
I just used 0.6 Ohms for L1/ 0.38 Ohms for L2/0.34 Ohms for L3/0.15 Ohms for L4.
If you use coils of say between 0.3-0.9 Ohms on your woofer, you can vary your output of +/-1 dB @100Hz. With a 3.9mH L1 and a 0.3 Ohms internal resistence you get more bass. But this is not so important for you right now. You have to decide in the speakers first and then the xover points at which those speakers will sing. If you keep changing very much you will not achieve a good result. Unless you keep testing all the time, for ever. That's only my opinion.:dead:
 
:bawling: I JUST PUBLISHED INTERNAL RESISTENCE (SIMULATED) FOR THE XOVER COILS (INDUCTORS).

SPEAKERS IMPEDANCE ARE THE ONE'S AVAILABLE FROM THE MANUFACTURERS. In this case:
Woofer Re=5.7 Ohm
Mid Re=5.8 Ohm
Tweeter Re=4.8 Ohm

omni, you might be right it's just a simulation and all that will depend in the room or place of listening, format of the front panel, output of the mid (dB's), etc etc etc, and I agree with you that the 0.4 Ohm is a good value for a 3.9mH L for a start. But who cares if you don't have a stable project to choose from and do the simulations. Can you answer that? At least for all the work done. I don't. If at least grant can say that the speaker sound's great (or not) that will be something... see you all next year. (I am severely... tired) 😎
 
Inductor,
The work you did is greatly appreciated, thanks!
Tinitus and Pit offered alternatives to the MCA15, so I thought the least I could do would be to check them out. Both the Fostex and Tangband are imho, not my best choice, so I'll still buy the MCA15's
and 27TFFC's asap. best wishes...

Hi Omni,
How are you going with your xo's? Well I trust. kind regards, grant
 
grant, is not you...
what can I say... anyway, good luck :wiz:

last minute edit:
grant, the tweeter is fine with the mid as I showed on the xover plan. They don't cancel at 1500Hz if they are inverted (mid 180º shift). Leave it like that if you use that 2.order xover for 1K900 xover point that is very good both for the mid freq. and for the tweeter response and much lower Fs.
 
Inductor, I am sorry if I stepped on your toes.......................Grant, crossovers are coming along........I just had a talk with the inductor supplier and we agreed that I would do some listening tests, and if I have problems with the current inductors, via those listening tests, they would make good on my purchase, by replacing them..............I trust they will honor their word............I will post a picture of the crossover in progress, here, shortly. Beyond that, I am looking at Frankies' audition by the end of the week........I will keep you posted..........Tinitus, it has been a while.........I hope all is going well for you these days...........I can't wait to hear Frankie sing out, with gratitude, all the help you, Grant and Sreten have kindly afforded me...............I will keep you all posted............Respectfully...................Omni
 

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