DIY crososver design [Archive] - Audio & Video Forums


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08-06-2004, 09:38 AM
Anybody have any info on this? Like what frequency is it set at, etc...
Not much is said about it.

Anybody have a frequency response plot of this speaker with the newest crossover specs?

08-10-2004, 01:29 PM
I priced the individual components and the price difference between the parts and having madisound build them was only $6 so I had them build mine (all 5). I belive the xover is around 2700

08-28-2004, 11:43 PM
Anybody have any info on this? Like what frequency is it set at, etc...
Not much is said about it.

Anybody have a frequency response plot of this speaker with the newest crossover specs?

I estimate the xover frequency to be 2,600Hz. I put the new xover (with 2Ohm resistor to pad down the tweeter a bit) into speakerworkshop out of interest. (The frequency plots are based on infinite baffle - I don't think I linked it to an enclosure so don't worry about it dropping away from 150Hz down....above 500Hz is indicative.)

Please note - these are estimations, modelled on Peerless' published frequency and impedance graphs (not measured). also - I don't know why but I had to invert the tweeter to avoid a null @ xover (as you'll see in the xover diagram) - not the case when you build one....


08-29-2004, 04:42 PM
Thats a large pad. Ed recommended between .5 and 10 I do believe. I was thinking of getting a 5 of the 2ohm as my boxes are almost complete. I sure do like that plot though. I am really anxious to get these boxes done LOL.

08-30-2004, 04:30 AM
Yeah, that mid-bass dip is all but gone, I've got to package all my stuff up in the next 2 days...I'm hoping unpacking goes rather quickly and that I can just jump right back into these. Got the house all bought...basement should be finished by the time I arrive. I should be able set up shop faily quickly in the garage. I've still got to finish the PeeCreek's, too (might buy the Usher tweets for those and swap them to see how they hold up to Ed's speakers).
Paul, can you recommend me a Plunge Router? Or were you the one cutting circles with a jig saw and dremel?

08-30-2004, 05:18 AM
Get a good plunge router--one that will last you a life time. I recommend the brand I'm using which is a porter-cable (I think its 3.5hp) and an assortment of bits (straight, round over, cove, dovetail, etc.).

My boxes are looking good. I put the second coat of primer on yesterday and will sand tonight. I think I will have to put a 3rd coat on at least one of them as I can still see that I did not sand the glue line well enough on one box. Other than that, they are as smooth as a baby's ass. I may be able to apply the first coat of enamal in a few days.

That graph has me pumped up but I don't want to rush it. Well, your gonna be tired moving so I wish you good luck and take it easy. Easy as in don't hurt yourself moving heavy items, etc. You only got 1 back so take care of it. Later, Paul.

08-30-2004, 05:29 AM
Me move? No new employer is covering most of that so, I've boxed up the fragiles as best I can, and I'll let the movers handle the rest...
Porter Cable seems to be the most common one recommended...guess I'll have to grab one.
Sounds like you're many of these are building again? What color (or colour now, I'm Canadian again).

Wonder if you'd have saved time veneering MDF like I'm doing? Maybe I'll try gloss black paint for Wayne J's speakers.

08-30-2004, 09:36 AM
Yes, I think veneering would have saved time. Unfortunately, I do not know anyone who has veneered and was scared to try it on my own. I am building 5 of them. I am going for that piano black gloss look where you can see yourself in them. There was a good article on how to do this on PE tech talk a week or so ago. Ya I use both color and colour at times. I don't really think about it, it just happens sometimes. Later, gotta go back to work. Paul.

08-30-2004, 10:14 AM
can you recommend me a Plunge Router? Or were you the one cutting circles with a jig saw and dremel?
Hey kexodusc

Using a jig saw and a Dremel tool was very hard for me to cut circles in 3/4 inch MDF. I went through this about a year ago. Cutting out circles was a problem until I got a Jasper Jig. Parts Express had a special on them at the time. Other woodworking dealers sell them online as well. They make the whole job of cutting the circle and countersinking a speaker easy. Before choosing a plunge router, you should check out Jasper's instructions on which plunge routers fit their jig. (I'll try to attach the file) There are holes predrilled in the jig that fit these plunge routers:

Bosch 1613, 1615
Skil 1823, 1825
DeWalt 621, 625
Fein FT-1800
Elu 177
Porter Cable 7539, 7529, 690 series
All Sears, Ryobi, & Makita
Freud FT2000E
Hitachi M8V, TR12, M12V
Even if you don't want a Jasper jig now, you may change your mind later.
After reading too much about about plunge routers on the internet, and after some good advice from Dick Hertz on this forum, I bought a DeWalt 621. I like it and would recommend it. The Bosch plunge router is also well received. Here is one review of plunge routers that is worth reading

There are other newer models available now that may also fit the Jasper jig. You can email Jasper Audio to ask what fits their jigs.

08-30-2004, 10:21 AM
The attached file didn't appear. Go to

Jasper Audio
3612 Mangum Road Suite 108
Houston, Texas 77092 (

I bought the Model 200 jig.

09-02-2004, 12:05 AM
.... got around to modelling the box with the 850122

I estimate the internal box volume is 10.58 litres. With a port @ 152mm (6") length and 2" ID, that would give a tuning frequency of approx 55Hz. Attached is the modelled response of the woofer in an arbitrary box (courtesy WinISD)

09-02-2004, 09:44 AM
Dave, could you post the plot without the 2ohm resistor? Thanks, Paul.

09-03-2004, 01:10 AM
Sure Paul,

There doesn't appear to be much difference. As expected you get a lift of a dB from the tweeter so it's a hard call. I can see why he recommended quick connects so it is easy to switch out resistors to try.

(I was trying to link the enclosure to the graph so we could estimate the low end response but can't figure out in speakerworkshop how to do it.... )


09-03-2004, 05:25 AM
Thanks Dave, I'm going to try it without the resistor first and then if I think its a little bright add the 2ohm resistor. I ordered them just in case. It would be interesting to see where the lower end starts to drop off but madisound has the frequency response from 45hz-20khz +/- 2db which is pretty darn good for a monitor of this size. Thank you very much for the second graph. Paul.

09-03-2004, 05:41 AM
Speaker city's response is the same, Wayne J's PeeCreeks which I'm also building (same 850122 woofer) have the cabinet tuned to just under 50 Hz, so I don't doubt the 45 is possible.

09-03-2004, 07:33 AM
When I measured my speakers with test tones and SPL meter I got 38hz before they dropped off. Of course this is in my listening room environment variables. These speakers on their own have decent bass response. Saying that, I wouldn't part with my Tempest sub. I firmly believe most systems (maybe all?) benifit from a seperate subwoofer.

09-03-2004, 10:46 AM
Yeah, I'd agree with that, MCH. Where do you cut off your LFE's then with these? I'm thinking of a cut-off at 60Hz, or maybe a gradual crossover at around 50 Hz, but I generally prefer the cut-off.

09-03-2004, 12:30 PM
Hello Paul,

I couldn't rememebr if you were making the xovers yourself. If you are ordering the xovers from madisound premade - they come already with the 2ohm resistor installed. I ordered 2 more 2 ohm resistors thinking they didn't include them onboard :-) Anyway - if I find the 2ohm is a little too much padding, I'll wire the extra 2 in parallel to give me just 1 ohm of padding.

I'd like to get an electret capsule mic next and do some actual measurements. I'm replacing some older wharfedales (8" 2 way) which have ok bass but poor midrange (what attracted me to the DIYs).


09-03-2004, 12:55 PM
Heres a picture when I first started the boxes. When I have finished them I will post the finsihed product. This is my first time trying to get pictures up here so hope it works out.

09-03-2004, 02:33 PM
There's that plywood...looking good Paul. Looks more organic than the 4 baffle-less boxes I've got.

Just remember, before you start brushing your teeth and fixing your hair in them shiny black boxes, send us a few pics.

09-08-2004, 05:24 AM
i sanded through to the primer. Triple darn da*n. It was a very small spot so I thought to myself just leave it there, it's fairly inconspicious. I showed my wife my work and guess what? The first thing she said was what is that white spot there. Jeez. So i put some more enamel on the spot and hopefully it will feather out nicely. If so, then I will put another light coat of lacquer and begin the sanding, compounding, and polishing again. But I have to say that the box did have that piano shine that I wanted (shaving and brushing teeth in it look). So it's a long tedious process, but the payoff is a great finish. I just learned the hard way not to be so heavy handed when sanding the lacquer finish. Also, I thought I had them pretty smooth but when that lacquer goes on it tells the story whether you did or not. Well, I'll chalk that up to experience on the first box and hopefully the other four will go smoother now that I know what to do. This is taking longer than expected though so it looks like I might ( I stress might) be done this weekend if I can get all the other boxes sanded and lacquered before Friday. Have a good day! Paul.

09-08-2004, 05:31 AM
Doh, tough luck, I'm some glad I decided to go with veneer. (we'll see how that turns out)
I was thinking, for the PeeCreeks (which will probably go upstairs in the new office room) I might try a glossy red or blue colour for something different. If you had to estimate how many hours of prep, sand, and paint work you spend on each speaker after the cabinet is assembleed, what would it be?

09-08-2004, 06:33 AM
First off choose a oil based spray can enamel (unless you have a sprayer). The darker the color the more mirror like will be the finish. Dark red or dark blue should work out fine. I used rustoleum black gloss enamel from walmart. I just used some .99 cent equipment primer (about three coats). Let the primer coats dry about a day (you can cut it short if you dont put it on to thick) but a day is good for my region where humidity is always a problem. So expect to spend a 2-3 days priming and sanding the boxes. You want to the primer coat to come out flat and shiny. Then apply the first coat of enamel and let that dry for 3 days. Then sand and put another coat and let it dry for 3 more days. Sand again, and then apply the lacquer. The lacquer dries pretty quick so 1 day is a good dry time even though it says 30 minutes. I would say overall that I have spend about 10-15 hours in sanding. Here is an article that I used as the basis for the piano mirror look:
the looks like a geek but does wonders with finishing.

09-08-2004, 06:37 AM
Yeah, geeks build computers, cool people build speakers :D

That 10-15 hrs sanding is for what, 4 or 5 speakers Paul? (please don't tell me 1 or 2)
All by hand or can you cheat?

09-08-2004, 06:54 AM
After spending about 3 hours sanding the lacquer and compounding, and polishing 1 speaker I went out and bought a $39 dollar orbital sander from walmart that came with a compounding pad, buffer pad, and some sanding discs. I wish I woulda done that from the start. It's farily ez to find up to 400 grit sanding discs but it gets harder the higher you go so the final sanding will probably be by hand. The 600, 1000, 1500, 2000 grits. It would be nice to find a 600 grit sanding disc because thats used the most. The 600 grit is used to sand the enamel coats and the first pass on the lacquer. Once its smooth, you move up to 1000, then 1500, and 2000 on the lacquer. So yes, the orbital sander can save copious amounts of time and energy. Hand sanding is tedious work but I sure have burned off a lot of calories doing it. Needed to lose some weight and lower the colesterol level anyway. Oh, I couldn't find the higher grits at home depot, walmart, etc. so I went to a auto parts house. They will have it along with the fine cut compound and swirl remover. Oh, and don't get acrylic enamel, get the oil based gloss enamel. The longest part is waiting for the enamel to dry. You must let it dry before sanding or you will muck it up cause it will be to tacky once you cut through the inital gloss layer. Anyways, if you dont have an orbital sander go out and get one and save yourself a lot of time. I hand sanded all my boxes and it was a pain. My fingers still ache, expecially the right index finger LOL.

09-13-2004, 11:58 AM
I could not be happier. These speakers just amazed me with their clarity and imaging. I personally wrote Ed a thank you email for posting this design. My friend is bringing in his digital camera tomorrow so I will take some pictures of them and post them in the next few days. You know, I was expecting a small difference is sound quality but that was not the case. The difference was so noticeable that I just sat and listened to them for a couple of hours. It's like everything blends together so well. Nothing is louded or quieter than other parts of the music. The crossover just blends them together as a whole. I will be doing a writeup review on these when I get time (still gotta finish 3 more). Stay posted as the pictures will be forthcoming.

09-13-2004, 01:08 PM
Congrats Paul...What speakers were you using before?
Can't wait for the pics.
I'm almost all unpacked and hopefully can find some time in the next week or two to get back at'em.

09-13-2004, 01:12 PM
an entra two center channel, entra three mains, and bose 201s in the rear and a MKII 12 Titanic subwoofer.

09-15-2004, 07:58 AM
Here are some pics of my AR.Com. They actually shine much better than the photo shows but I guess the sun and angle were not right. I can actually see myself in them and inside they look spectacular. Notice that you can see the peerless tweeter from the rear port hole which I thought was kinda cool. Well, three are done and by the weekend I should have the other two finished. They sound great. Paul

09-15-2004, 09:01 AM
helluva job, Paul...especially the grills...I haven't figured out how I'm gonna do the grills on mine.

09-15-2004, 09:19 AM
Thanks, I'm going to take some more pictures inside this time and see if they come out better. The screws are actually brass which bring a look of elegance to the black.

09-15-2004, 09:29 AM
Unpacking is taking alot longer than I hoped it would. I start my new job on Monday too, but I'm hopeful I'll get around to finishing mine up before least starting up again.

Eventually I'm gonna do a head to head with the PeeCreek or U-Pee (depending which tweeter I decide to use) and my $800 Paradigm Studio 20's with some of my relatives, similar to Ed's comparison to the GR Research modified I'm hoping the results encourage people here to look into DIY more.

Whatcha using to polish those pretty things? Meguiar's? Mother's? Carnuba wax or synthetic?

09-15-2004, 11:59 AM
Used a lacquer finish then a lot of sanding. Then used fine cut compound to get the 1500 grit scratches out. Then used finish restorer for polishing. It said to wait a month before applying wax to give the enamel and such time to cure. Not sure on waxes, but I'll probably go to the auto parts house and look up one of those you mentioned. The wax will probably make them look more mirror like and have a tougher protective coating. The only problem I have found so far is that you can see the dust settling on top of them very easily. The mirror finish seems to say "look I have dust on me".

I just got the MDF cut for my stereo sub cabinets (my next project). I have two 8" Peerless CC subwoofers ready to go. I decided on a ported cabinet of 4 cubic feet with 2 2x6 inch ports for a tuning of around 25hz. The fs is 25 on them so I will not hear anything below that anyway. These will double as my stands for the front AR.Coms. The overall height including feet, sub, and monitor comes out to 36". The tweeter around 33" which is at ear level while seated. I think the wife is gonna ***** at me for the hugh sub cabinets though :-). This project will go much quicker since I only have to cut a few holes and its only two cabinets. Of course there is more space to deal with on painting. I'm going to make them the same color and finish.

Well, gotta get back to work and quit messing around here. New jobs are usually stressfull in nature till you get your feet on the ground so take it easy and just take whatever comes come. Thanks, Paul.