Any one have a cross-over for this?
I actually had an SB26 fabric dome tweeter I could have used with is cross-over:
https://www.diyaudio.com/community/threads/2-way-sb15mfc-08-sb26stc-04.315253/page-2
Is the cross-over in the link a good starting point?
Or Zaph has a good x-over for the Scan Speak 15W8530K00 and the Vifa XT25TG30-04:
http://zaphaudio.com/ZD5.html
Is it a better starting point?
I actually had an SB26 fabric dome tweeter I could have used with is cross-over:
https://www.diyaudio.com/community/threads/2-way-sb15mfc-08-sb26stc-04.315253/page-2
Is the cross-over in the link a good starting point?
Or Zaph has a good x-over for the Scan Speak 15W8530K00 and the Vifa XT25TG30-04:
http://zaphaudio.com/ZD5.html
Is it a better starting point?
Attachments
The XT25 is a great cheap tweeter but it doesn't cope well crossed as low as your typical soft dome, unless you're ok with higher HD or just needing lower overall output. A waveguide is a great add on for this tweeter. It really benefits from one, allowing a lower xover.
Edit - I see Zach uses an impedance notch with the 2.4k LR2 xover, which it will definitely need to not start honking down low.
Edit - I see Zach uses an impedance notch with the 2.4k LR2 xover, which it will definitely need to not start honking down low.
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okay, should have looked at XT25 cross-over schematics more carefully before I started. hochopeper from https://www.diyaudio.com/community/...-04-crossover-point-how-low-can-it-go.226238/ sums it up nicely:
"The challenge comes if you are wanting to use one of these tweeters with a passive crossover, you may end up with an expensive set of components for the crossover.
I haven't tried it, yet, but I believe that at least some of the problems that others have had with these tweeters is because they are (understandably) unwilling to build (and spend time designing) an expensive and complex crossover when they could simply buy a better tweeter!"
Any one have the sb15mfc FRD and ZMA files?
And XT25BG60 files?
Although I think my XT25BG60 files are accurate.
I can't recall where I got them.
Definitely should have gone with sb26 fabric dome tweeter and sb15mfc.
Cross-over was already done.
I didn't want to **** around with cross-over ******** for a week.
For xt25BG60 notch I got this wtf:
https://www.diyaudioandvideo.com/Calculator/SeriesNotchFilter/
Series Notch Filter
Re = 2.99 Ohms
fs = 589 Hz
Qes = 0.43
Qms = 1.31
"The challenge comes if you are wanting to use one of these tweeters with a passive crossover, you may end up with an expensive set of components for the crossover.
I haven't tried it, yet, but I believe that at least some of the problems that others have had with these tweeters is because they are (understandably) unwilling to build (and spend time designing) an expensive and complex crossover when they could simply buy a better tweeter!"
Any one have the sb15mfc FRD and ZMA files?
And XT25BG60 files?
Although I think my XT25BG60 files are accurate.
I can't recall where I got them.
Definitely should have gone with sb26 fabric dome tweeter and sb15mfc.
Cross-over was already done.
I didn't want to **** around with cross-over ******** for a week.
For xt25BG60 notch I got this wtf:
https://www.diyaudioandvideo.com/Calculator/SeriesNotchFilter/
Series Notch Filter
Re = 2.99 Ohms
fs = 589 Hz
Qes = 0.43
Qms = 1.31
| Parts List Capacitor C = 210.23 uF Inductor L = 0.35 mH Resistor Rc = 3.9714503816793894 Ohms |
These drivers seem to be similar to mine, the :
http://www.troelsgravesen.dk/Peerless_HDS830860.htm
I did notice before the Peerless_HDS830860 has very similar specs to the SB15MFC-08.
Slightly off topic:
Didn't buy the Peerless because:
A LOT of drivers that aren't SB Acoustics aren't really worth building cabinets for, for me personally, IMHO.
VIFA/peerless sound great, but build quality not as good as SB Acoustics.
No silver leads, sometimes, or rubber on leads).
Casting is rough.
No machining on top or bottom plate, even $200 SEAS drivers don't have this.
Not glued right, off center. Not enough glue.
Not packed right.
VC to lead wires exposed to elements, not fully glued.
THE XT25 vs the SEAS SB26: XT25 is fully glued I believe, but the SB26 is nicer and has silver leads.
I'll just pad the tweeter way down. I don't really like tweeters (or a lot of high FR), even the XT25 has a lot of high end "tings" and "Sssss" vocal sounds, like a snake
Any one have the sb15mfc FRD and ZMA files?
And XT25BG60 files?
Although I think my XT25BG60 files are accurate.
I can't recall where I got them.
http://www.troelsgravesen.dk/Peerless_HDS830860.htm
I did notice before the Peerless_HDS830860 has very similar specs to the SB15MFC-08.
Slightly off topic:
Didn't buy the Peerless because:
A LOT of drivers that aren't SB Acoustics aren't really worth building cabinets for, for me personally, IMHO.
VIFA/peerless sound great, but build quality not as good as SB Acoustics.
No silver leads, sometimes, or rubber on leads).
Casting is rough.
No machining on top or bottom plate, even $200 SEAS drivers don't have this.
Not glued right, off center. Not enough glue.
Not packed right.
VC to lead wires exposed to elements, not fully glued.
THE XT25 vs the SEAS SB26: XT25 is fully glued I believe, but the SB26 is nicer and has silver leads.
I'll just pad the tweeter way down. I don't really like tweeters (or a lot of high FR), even the XT25 has a lot of high end "tings" and "Sssss" vocal sounds, like a snake
Any one have the sb15mfc FRD and ZMA files?
And XT25BG60 files?
Although I think my XT25BG60 files are accurate.
I can't recall where I got them.
Attachments
Yeah, sorry for that bit of news on the tweeter. Maybe try a better Morel with a 104mm faceplate so you don't need to change the cutout size. The CAT308 is a much better one for lower xovers. Would go very well with the SS woofer.
If you don't want to spend that much, the Peerless DX26BG60 is a good dome for the money and will take the lower xover without too much fuss.
Third option priced in between those others js the SB 26STAC. Probably the best softdome tweeter under 50 bucks IMO.
If you don't want to spend that much, the Peerless DX26BG60 is a good dome for the money and will take the lower xover without too much fuss.
Third option priced in between those others js the SB 26STAC. Probably the best softdome tweeter under 50 bucks IMO.
Yes, I agree and that is the one in the pics SB 26STAC.
I was trying to decide between that one and the XT25 for a few hours.
Should have asked before I built the speakers, lol.
I usually ask, but often don't ask my questions clearly, maybe, so don't get a reply, for that reason and maybe others.
I think I'm going to try and use the cross-over in the attached pic, but probably model it in XSim first.
These drivers seem to be similar to mine, the :
http://www.troelsgravesen.dk/Peerless_HDS830860.htm
I was trying to decide between that one and the XT25 for a few hours.
Should have asked before I built the speakers, lol.
I usually ask, but often don't ask my questions clearly, maybe, so don't get a reply, for that reason and maybe others.
I think I'm going to try and use the cross-over in the attached pic, but probably model it in XSim first.
These drivers seem to be similar to mine, the :
http://www.troelsgravesen.dk/Peerless_HDS830860.htm
Attachments
I don't see why the XT25BG60 would need an expensive or complex crossover. Profiguy makes the correct point in post #2 that the XT25 can't crossover as low as some other tweeters, you are probably limited to 2.5khz, maybe 2.0khz. But using with a 5" poly cone woofer, I don't see that being a problem.
He also correctly states that this tweeter works great in a waveguide, in particular in has been used by many in the Visaton WG148R waveguide - you need to fill the gap between tweeter and waveguide with something like clay or blue-tac but there is a 3D printable adapter available on Thingiverse. If you Google the XT25 in the WG148 you'll find some results.
The DX25BG60 Profiguy references in #5 is a great tweeter, can crossover much lower (which you don't necessarily need) and is on sale at Madisound for $30.
Your biggest problem is that it is unlikely you will find an existing crossover for any of these given drivers. You need actual measured drivers in actual cabinets. You will not get a good notch filter using online calculators but need to put the actual driver impedances into simulation software.
He also correctly states that this tweeter works great in a waveguide, in particular in has been used by many in the Visaton WG148R waveguide - you need to fill the gap between tweeter and waveguide with something like clay or blue-tac but there is a 3D printable adapter available on Thingiverse. If you Google the XT25 in the WG148 you'll find some results.
The DX25BG60 Profiguy references in #5 is a great tweeter, can crossover much lower (which you don't necessarily need) and is on sale at Madisound for $30.
Your biggest problem is that it is unlikely you will find an existing crossover for any of these given drivers. You need actual measured drivers in actual cabinets. You will not get a good notch filter using online calculators but need to put the actual driver impedances into simulation software.
What acoustic offset are you using for the woofer in XSim (Mod parameter I believe)?
What FRD data are you using and have you applied baffle step losses and diffraction ripple to BOTH drivers?
What FRD data are you using and have you applied baffle step losses and diffraction ripple to BOTH drivers?
"mod sensitivity" I had to adjust to make the FR graphs appear in the right location on the Y axis.
BTW FP trace cut off window set to 20 HZ to 20 KHz works for the x-axis no matter what the XSIM lower frequency cut off point is.
The stretch on the Y -axis (not location on the Y-axis) on FP trace is harder to gauge.
Also "bounded trace" is unselected in FP trace.
"mod delay" is 0 for both drivers.
no baffle step or ripple diffraction.
BTW FP trace cut off window set to 20 HZ to 20 KHz works for the x-axis no matter what the XSIM lower frequency cut off point is.
The stretch on the Y -axis (not location on the Y-axis) on FP trace is harder to gauge.
Also "bounded trace" is unselected in FP trace.
"mod delay" is 0 for both drivers.
no baffle step or ripple diffraction.
Ok - if you have a flat baffle, then your acoustic offset needs to be allowed for (mod delay / Z). The woofer voicecoil / dustcap will be behind the tweeter dome. this means for the same frequency (around your crossover point), both drivers will be out of phase with eachother. this will cause dips / peaks in your crossover response if you simply ignore it. you need to estimate how far behind the woofer. ~ 25mm is a reasonable amount for most 5" midwoofers - but check yourself. By putting this into XSim, you can then play with asymmetric slopes until the phase aligns, meaning good summation in the crossover and a flat response.
A few simple manipulations of the manufacturer data will help get you closer to reality. I think your time is better spent getting your input data as close as possible (if you are not going to measure yourself), rather than tweak a crossover on flawed input files.
A few simple manipulations of the manufacturer data will help get you closer to reality. I think your time is better spent getting your input data as close as possible (if you are not going to measure yourself), rather than tweak a crossover on flawed input files.
Thanks Dave, I did actually estimate "-1 [in] mod delay" (25.4mm) for the SB15MFC30-08.
I didn't really know how to accurately measure the acoustic center difference of a XT25 and a SB15.
I mean I know where the top of the dust cap is on the woofer and where the VC/ring is on the tweeter.
Here is my latest, maybe final cross-over? What do you (any one) think?
The notch filter is NOT grounded.
I copied the cross-over from some one and noticed the notch filter didn't do much.
I didn't really know how to accurately measure the acoustic center difference of a XT25 and a SB15.
I mean I know where the top of the dust cap is on the woofer and where the VC/ring is on the tweeter.
Here is my latest, maybe final cross-over? What do you (any one) think?
The notch filter is NOT grounded.
I copied the cross-over from some one and noticed the notch filter didn't do much.
Attachments
Can you please turn on individual driver responses? You should be able to see summed / total response and woofer and tweeter at same time
When you are flipping polarity I see the woofer peaking above the summed response meaning your crossover could have better phase alignment
When you are flipping polarity I see the woofer peaking above the summed response meaning your crossover could have better phase alignment
Not sure where all the criticism of the xt25 is coming from…..dollar for dollar, it just might be the best tweeter available if crossed 2.5khz or higher.
P.S……I’ve never had to notch an xt25…..there’s nothing in the response once it’s mounted on a baffle to indicate it needs one. I often laugh at some audiofool comme tray like ‘the tweeter has sibilance’……did they ever consider that maybe the sibilance is in the recording? Lol
P.S……I’ve never had to notch an xt25…..there’s nothing in the response once it’s mounted on a baffle to indicate it needs one. I often laugh at some audiofool comme tray like ‘the tweeter has sibilance’……did they ever consider that maybe the sibilance is in the recording? Lol
Yes, total should be higher.
SB FR curve and impedance:
http://zaphaudio.com/temp/SBAcoustics-SB15MFC30-8-FR.gif
The XT25, I don't know where I got that from.
Should I redo the XT25 tracings?
Use the SB tracing from Zaph's data? Or some where else?
SB FR curve and impedance:
http://zaphaudio.com/temp/SBAcoustics-SB15MFC30-8-FR.gif
The XT25, I don't know where I got that from.
Should I redo the XT25 tracings?
Use the SB tracing from Zaph's data? Or some where else?
I would redo the Xt25 tracings. your version is here:
https://www.wagneronline.com.au/attachments/Audio-Speakers-PA/vifa/XT25TG30-04.pdf
I don't know which Xt25 Zaph measured and can't find / remember his measurement conditions. Given the huge Y axis and "smoothing" I can see, I wouldn't use Zaph FR data.
I do have the SB15MFC30-8 traces at home. I'll upload these for you.
Please tell me your baffle dimensions and driver placement on baffle and also box volume (and tuning if vented). I can then apply your specific box and baffle diffraction which will give curves closer to reality than just using manufacturer data. I will upload both options so you can see the differences.
https://www.wagneronline.com.au/attachments/Audio-Speakers-PA/vifa/XT25TG30-04.pdf
I don't know which Xt25 Zaph measured and can't find / remember his measurement conditions. Given the huge Y axis and "smoothing" I can see, I wouldn't use Zaph FR data.
I do have the SB15MFC30-8 traces at home. I'll upload these for you.
Please tell me your baffle dimensions and driver placement on baffle and also box volume (and tuning if vented). I can then apply your specific box and baffle diffraction which will give curves closer to reality than just using manufacturer data. I will upload both options so you can see the differences.
You'll find a range of SBA driver files in here:
https://drive.google.com/file/d/1Q7rwSwxjMpCGpmKqAOBZIsj1-qnvGgjq/view?usp=drive_link
https://drive.google.com/file/d/1Q7rwSwxjMpCGpmKqAOBZIsj1-qnvGgjq/view?usp=drive_link