Hi Everyone,
I need some guidance as I am new to DIY. I have purchased a pair of Dayton 7Inch woofers that I will retrofit into some older Focal 707s boxes. Im having trouble choosing a tweeter that will match this woofer. Any help would be much appreciated. thanks in advance
I need some guidance as I am new to DIY. I have purchased a pair of Dayton 7Inch woofers that I will retrofit into some older Focal 707s boxes. Im having trouble choosing a tweeter that will match this woofer. Any help would be much appreciated. thanks in advance
Hi sorry,
its the Dayton RS180P-8, the crossover i have is the Dayton Audio XO2W-2K 2-Way Crossover 2,000 Hz, the box is the old Focal Chora 707's. Although its a little bigger than the recomended 18L for this woofer. it is such a strong and well braced box that i didnt want to throw out.
its the Dayton RS180P-8, the crossover i have is the Dayton Audio XO2W-2K 2-Way Crossover 2,000 Hz, the box is the old Focal Chora 707's. Although its a little bigger than the recomended 18L for this woofer. it is such a strong and well braced box that i didnt want to throw out.
Here is a link to a speaker called Seriatim which uses that woofer in a 14.5L cabinet and the HiVi RT1.3WE tweeter. Note, the PDF writre-up is embedded in the first post. You could put a styrofoam block in the Focal cabinets to reduce the volume a bit. The problem here is the baffle of the Seriatim is not a simple rectangle. It will matter, so the crossover won't be exact but almost surely better than an off-the-shelf crossover.
Google search why "off-the-shelf crossovers" are typically bad.
Another speaker that uses the RS180P-8 is the Slapshots but it is an MTM in an 24L cabinet. Another Aussie, Geoff Millar, has them and loves them. But I don't see how you could build them without a new Cabinet. @GeoffMillar - there was never a TM version of the Slapshots, was there?
Google search why "off-the-shelf crossovers" are typically bad.
Another speaker that uses the RS180P-8 is the Slapshots but it is an MTM in an 24L cabinet. Another Aussie, Geoff Millar, has them and loves them. But I don't see how you could build them without a new Cabinet. @GeoffMillar - there was never a TM version of the Slapshots, was there?
Thanks for that. Unfortunately, that tweeter in Australia would be around $108 AUD, which is double what i had budgeted for. All this time ive been looking at potential dayton tweeters but again, Im not sure that is an option
To match that woofer, you'll need a tweeter of 90dB sensitivity, and an Fs of ~ 1Khz. Have a look at the SB offerings on Loudspeaker Kit.
If you post the internal dimensions of your Focal boxes, a suitable tuning can be suggested. THEN, you can start to design a suitable xover.
If you post the internal dimensions of your Focal boxes, a suitable tuning can be suggested. THEN, you can start to design a suitable xover.
For Dayton, I'd recommend RST28-F.
SB Acoustics has several that would work, SB26STAC is a good one to look at.
SB Acoustics has several that would work, SB26STAC is a good one to look at.
I like this little planar. Can you get it locally?
https://www.parts-express.com/Beston-RT002A-Ribbon-Tweeter-277-112
https://www.parts-express.com/Beston-RT002A-Ribbon-Tweeter-277-112
Thanks Guys the SB26STAC is about $49AUD which is more in line with my budget so will give that a go. another randam question if i may, the woofer unfortunatley doesnt fit perfectly in box and was wondering if you guys have any advice on how i can make it fit i.e. organising a metal plate of sorts that i can mount speaker to and then fit into box or ditch box all together?
As above, or as you said a metal plate over the whole lot (with sealant against the baffle), or a completely new baffle.
You could put some kind of ballast in the bottom of the boxes to take up excess volume, which will assist in keeping the box stable too.
You could put some kind of ballast in the bottom of the boxes to take up excess volume, which will assist in keeping the box stable too.
I used to cut a new baffle from 3/4 to 1” birch ply and glued it on the original several times. I often incorporated facets to improve directivity.
I have a spare pair of RS180P-8s, I’ve thought of doing a two way but don’t need more speakers at the moment. Look up Wogg Music’s website, where his Super Nova Minimus design matches the RS180 with a Vifa tweeter echos available from Wagner in Oz, about $65 ea. Doing this on phone so can’t send the link, sorry
Geoff
Geoff
Your biggest problem is here.
A pre-made crossover like the one posted makes many assumptions about the drivers you are pairing. For a start - it assumes matched sensitivity between drivers and that they present the rated impedance at 2,000Hz (your RS180-P is ~ 10ohms and SB26STAC ~ 4 ohms).
Basically impedance will shift the crossover point and your premade crossover will not address mismatched sensitivity of the drivers.
In addition it is unlikely this crossover applies appropriate baffle step compensation.
Then you have the issue of in phase behaviour meaning the drivers are working in unison through the crossover.
You'd be better off not using this crossover, or stripping it for parts - hopefully re-using them in a new crossover design. The best to worst options are:
1. Measure the drivers yourself and design a crossover
2. Use factory supplied measurements WITH your own baffle diffraction applied and design a crossover
Not recommended:
3. Use factory supplied measurements WITHOUT your own baffle diffraction applied and design a crossover
4. Use an online calculator to work out parts values
5. Use a premade crossover (like yours).
You are unlikely to do any harm by using this dayton crossover (i.e. it is unlikely to cause a very low impedance dip to your amplifier). My suspicion is that your speaker will sound bass weak / bright / shouty.
-small router with a straight bit and set the depth correctly to the current depth of the driver inset. Route over the sides of the circle a bit more with it.
STAC is a good tweeter. 👍
Note though that the STAC is going to need a much larger hole/opening than what you currently have. If you can’t adjust for that then you can either make a new baffle or just make an entirely new cabinet.
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