I want to build my first 2 way speaker. Iam using the Parts Express https://www.parts-express.com/Knock-Down-MDF-0.04-ft-Micro-Bookshelf-Cabinet-300-7060?quantity=1
and will be using Peerless xb20bf00-04 tweeter paired with Fountek Fe85. I have these speakers sitting around and would like to try and build a 2way for my new home audio system. I have very limited knowledge about this but would like to give it a shot. Any help would be greatly appreciated.
and will be using Peerless xb20bf00-04 tweeter paired with Fountek Fe85. I have these speakers sitting around and would like to try and build a 2way for my new home audio system. I have very limited knowledge about this but would like to give it a shot. Any help would be greatly appreciated.
As long as the woofer is more sensitive then the midTweeter you should be fine. The Boenicke W5 Uses FE85 and there is considerable discussion here: https://www.diyaudio.com/community/threads/boenicke-w5-clone.310367/
dave
dave
I know on ampslab the 2 speakers I am wanting to use he has measured and say they pair nicely. That is why I was hoping to stick with them. https://www.ampslab-spk.com/2019/05/06/supermicro-dx2/
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That link provides response curves. As this is a personal project you could probably use those as a guide.
Jeff Bagby's Quarks used that FE85 in the 0.04 cf knock down cabinet. XO was very simple so it probably wouldn't take much to modify it for your tweeter.
https://techtalk.parts-express.com/...ery/65800-the-quarks-m-o-s-d-computer-speaker
https://techtalk.parts-express.com/...ery/65800-the-quarks-m-o-s-d-computer-speaker
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I want to use the Fe85 as woofer and the peerless tweeter for the highs. Similar tto Jeffs design. I ordered the same box and port tube. My difference is the crossovers.
Do you have, or do you plan on purchasing, any measurement equipment?
I have the drivers and crossover parts for the Quarks on a shelf. I'm buying some stuff from Parts Express at the end of the week and can throw a DX20BF 4 in my cart and help you out a little.
I have the drivers and crossover parts for the Quarks on a shelf. I'm buying some stuff from Parts Express at the end of the week and can throw a DX20BF 4 in my cart and help you out a little.
Nice ! Would love the help. What parts are you getting for the crossovers? I purchased pre built xovers from parts express but i would need 2 inside each box.. which the speaker boxes seem small already. I would appreciate the help on the crossover part, thats where I am spinning my wheels at. I have the dayton mic umm 6 mic and limited knowledge of rew. But can work it a little. Do you mean multimeter?
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I wouldn't know what xo parts until we measured and simulated a xo. But I would start with the xo for the Quarks with a different resistor since the DX20BF has higher sensitivity than the ND20FA. Then tweak from there. These are budget drivers in a 0.04 cf cabinet so there is no point going crazy.
I did mean mic, not a multimeter.
You will first want to build the cabinets. Then measure both drivers with the UMM-6 on their axis in the cabinets. In this case they are so close it won't really matter if you just leave the mic in the same place. If you don't have DATS or a LIMP jig we can theoretically use manufacturers impedance curves (we'd have to simulate the "in-box" impedance of the FE85 in VituixCAD), but if I get the tweeter I can measure the impedances.
Then we put in the SPL measurements in VituixCAD, use the minimum phase feature, put in the impedance curves and simulate a xo, starting with the Quarks xo. (Similarly, if I get the tweeter, I can measure both drivers with a EMM-6 and it will have actual phase data.) I have xo parts, so can build a test xo and measure against the simulation. When we get a final xo, you can buy the parts.
So, if you haven't built the cabinets yet, start there. If this is the build you want to do, I'll order the tweeter Thursday or Friday and expect to receive it Monday or Tuesday.
Oh yeah...if you can send the pre-built xovers back, then do it.
Have you started assembling the 0.04 cf cabinet? Do you have the tools to flush mount the tweeter?
- If you look at the images of the Quarks, both drivers are surface mounted (which is easier - i.e., just attached onto the face of the baffle, versus routing a shallow recess to flush-mount them.) But, the tweeter in the Quarks is smaller than the DX20BF. If you look at Michael Chua's speaker they are also both surface mounted, and this is your larger DX20BF, but his cabinet is bigger. I think in the 0.04 cf cabinet you may not have room to surface mount the FE85 and DX20BF. It "looks" like you could squeeze them onto the front baffle, but that is ignoring that the inside sruface is limited by the width of the walls. It might be possible, but you might need to mock it up on a piece of cardboard or in Sketchup, or something. IF you can recess the tweeter, then you could overlap the drivers, surface mounting the FE85 slightly overlapped on the tweeter. (See Part's Express'es C-Notes as an example.) If you can do this, it would probably work and would probalby look cool 🙂
- Do you have port tubes? Since the Quarks have proven to perform well in terms of box tuning you should use a 1" internal diameter x 4" length port, which can either be 1" PVC or Parts Express part # 260-470.
I will be receiving the cabinets and the port tube shortly, possibly on Monday 🙁 .. I ordered them and Ups brown is slow. I will begin construction on the cabinets soon after.
1. As of having tools to reccess the speakers, I do and I don't. I have a couple of routers but have not used them in a long time. I need to buy a decent circle jig. I am in construction and own a roofing company, so tools and working on projects with alignment and plumb are not foreign to me. A side note parts express, said that I could for making room just set the tweeter slightly off center if I cannot get the speakers to fit.
2. I ordered a port tube with the xovers and they will be arriving today or tomorrow. The port tube is the same one Jeff ordered and the one you mentioned.
I will make a mock up for fitment.
1. As of having tools to reccess the speakers, I do and I don't. I have a couple of routers but have not used them in a long time. I need to buy a decent circle jig. I am in construction and own a roofing company, so tools and working on projects with alignment and plumb are not foreign to me. A side note parts express, said that I could for making room just set the tweeter slightly off center if I cannot get the speakers to fit.
2. I ordered a port tube with the xovers and they will be arriving today or tomorrow. The port tube is the same one Jeff ordered and the one you mentioned.
I will make a mock up for fitment.
The Jasper jig is so convenient, and while its not really expensive it is still a waste if your only going to use it once. If you Google search, there are a lot of simple DIY circle jigs out there. You could probably get by with a hole saw and maybe a rabbet bit if you had those on hand.
Pictures below show the overlapped drivers and the "slightly" off center tweeter. While offset tweeters can have some advantages (and some disadvantages), this doesn't look very good to me. Also, a waveguided tweeter like this isn't really going to benefit. If you can get the overlapped drivers to work, I think you will like it better. In this screen shot with the overlapping drivers, the tweeter is centered 1 1/2" from the top and the midwoofer 2 1/4" from the bottom.
Will you round over the sides with a roundover router bit? You can see that there isn't quite enough room on the edges for a 1/2" round over, but you could do 3/8". This would be more for looks, as (1) a small round over doesn't really do much for diffraction and (2) roundovers also make less difference for a waveguided tweeter.
I will get one, jig. I am into car audio that is why I have a mic and lots of speakers. I want to build a subwoofer next. I have a dayton audio ho 10" also 2 pairs of Silverflute 8" one pair 4 ohm and one pair 8 ohm. Numerous car speakers etc. I also build subwoofer boxes for my trucks and sometimes friends.
I will be going for the overlaped set up. I get my boxes tomorrow 😊 excited!!! I also received my xovers and port tube today. So we are a go this weekend to start the cabinets.
I have the idea of doing a round over 3/8" at least on the sides of the box. Do you round over the inside of the speaker openings also?
Have you been able to order your parts?
I will be going for the overlaped set up. I get my boxes tomorrow 😊 excited!!! I also received my xovers and port tube today. So we are a go this weekend to start the cabinets.
I have the idea of doing a round over 3/8" at least on the sides of the box. Do you round over the inside of the speaker openings also?
Have you been able to order your parts?
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The reason I suggested a 3/8" roundover is that you can see in the pic, the width of the FE85 doesn't quite leave 1/2". BUT...sometimes a 1/2" roundover doesn't quite go a full 1/2". So once you have the driver holes, you can drop the FE85 in and see if you can pull off the 1/2" roundover or not.
I usually use a 45 degree chamfer on the inside of the speaker openings. Typically, I leave a little material where the screw holes are which creates a "scalloped" look like the picture below. With a tiny 3" driver that may not matter as it doesn't weigh much at all. A cove bit also works. A roundover might work, you'll just want to drop the driver in afterwards and see - does it look like it can "breath"? It's usually pretty obvious if the driver looks like it is sitting in a "tunnel".
I ordered the parts yesterday but after 5:00, so I expect them to ship today and arrive Monday if shipping goes as it usually does.
Hopefully you haven't got far enough to drill a hold for the port tube. One thing I thought of...The 1" diameter by 4" long port will end up about 1/2" away from the inside edge of the front baffle. That was okay with the Quarks, because the smaller tweeter barely sticks out on the inside edge of the baffle. However the DX20BF is much deeper due to the waveguide and you will NOT be able to put the port right behind the tweeter. You don't really want it right behind the FE85 if you can avoid it, so hopefully you can put the port off-centered somewhere in the top portion of the box. Keep in mind you also don't want the inside edges of the port to end up right by the walls either, as that basically acts as a longer port.