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I have just had a thought about this that might be quite important. You are probably going to need to add mass to the PR to get the correct tuning frequency, the chances of it being right out of the box so to speak are remote. I'd hesitate before thinking about using this sub standing upright as the PR suspension is going to sag one way or the other & probably quite a bit. In my opinion your probably only going to be able to use it in a horizontal position to avoid the afore mentioned sagging suspension :doh:

I may be wrong, but i don't think i will be. I'd suggest modelling it in a speaker design program & see how much mass you'll need to add & then try it on the PR & see what you reckon :) Remember that it'll be sitting vertically (if that's the way you are planning it) constantly & not for just a few minutes...
 

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I'm new here, and I have never played with PR's before, but heres a little idea I just had regarding the sub standing upright and the PR sag. I would also think that the PR is going to have a sag value that may make it "bottom out" with the in stroke durring the really low notes if the PR is used in the top half. With mass added this would be even more so. Has anyone ever thought of incorporating a spring system under the PR? I think there are calculators you can use to figure the correct spring strength needed and compression for the wieght. If you could find the correct length needed for just the right amount of compression, I would think you could make the PR sit right mid-way when not used, and the spring would limit the in stroke. If this sounds useless please let me know. Just an idea lol.
 

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Discussion Starter · #23 ·
Good catch EH it will take 700 grams to tune the box to 21.75 Hz, Mike helped me with that on another thread. HTNut the subs will not be standing upright they will be on there sides with the Titanics firing outward and the PRs at the back. You are correct, I have been told that the PRs really won't work for the reasons you describe being in the horizontal plane. They will only work properly in the vertical plane. If you look at the picture on pg 2 I believe of this thread the left sub will be built into the stand that the 15" Dayton is sitting on (hard to see in the pic) and the right sub will sit between the 18" Mal X and the edge of the stand I am building.
 

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Discussion Starter · #29 ·
No, actually it is ash. Ash is the best bargain going in wood right now in Michigan, the Emerald ash borer disease has caused havoc here. Many many ash tress have been cut down and you can't transport the wood out of state. It turns out good for woodworkers, a surplus of ash, and it is a very hard wood and has a beautiful grain pattern, best of all it is only $3.50/board foot. I needed 142 board feet for my 3 projects so it was quite the savings. The next best price on wood that I liked was Red Oak at $5.50/ board foot. As for the stain it is a mix of Mahogany and dark Walnut 50/50.
 

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I think i'll hitch a ride on this one if you don't mind :T Honestly you don't know how lucky you are being able to source these sonotubes, nothing really like it this side of the pond :rolleyesno: Good luck with the build, recently received a few Exodus Audio PRs myself so it'll be interesting to see what you do :)

I just wish i'd had a digital camera when i built my rack, i'd like to see some pics, just to inspire others to DIY :T Maybe an alternative thread on the thing might be better, might help people out when using the site search if they want information on something similar?

Good luck & enjoy :)
Hi - I'm an ex-pat who could send you some contact info-or just search for 'White Cap on net. They will ship anything nowadays-probably do it cheap if they can get a lawnmower or something inside it too!
Steve
 

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Discussion Starter · #32 ·
OK phase two of my system rebuild project (the rack) is now done. I can now get to the subwoofer building. I finally recieved the 3/4" rabbeting bit I needed to finish milling the faceplates for the subs, the faceplates will match the rack and speaker stands. I am quite pleased with how it looks so far, quite a difference from the pic on pg 2 of this thread already. Pics of the sub build to follow next week.
 

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Discussion Starter · #34 ·
You aren't kidding , whats hard to see in the picture is the 18' Maelstrom X in the right corner and the Dayton 15" in the left corner that I use for 2 channel listening. The first time I cranked it up the pictures were hanging in every which direction, thank goodness for two sided tape. The bass is so good with these subs that I have had to go through those pictures on the wall and make sure the glass is tight in the frames, otherwise they will rattle, it has taken some time but I just about have it now. Can't wait to get these two new subs in the mix.
 

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Discussion Starter · #35 ·
Ok got back to work on the sub build yesterday and figured we would finish all of the cutting and all I would have left was sanding,priming,painting and assembly, all work that I can do at home as opposed to in my ex work partners shop. Well we cut the MDF into 6 23" sqares that we needed and made one plunge cut for the circle cuts for thePRs and one of us knocked the router off of the bench, thank God it wasn't me! Well when we determined that the circle was just the right size we turned the router back on and.......nothing the fall took the router out. So until we borrow another or get the router repaired the project is on ho;d again. Here are some pics of what is done so far, I took the cover paper off of the tubes, and have the faceplates rough milled and will be working on sanding and finishing them, also got the 3rd Ep-4000.
 

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Discussion Starter · #39 ·
I am not sure about that, someone with more experience building subs may be able to answer that. I probably wouldn't have thought of using the passive radiators until it was suggested here.
 

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Sounds good. I also find that when I took the port out of my Sonosub to replace it with a bigger port..It sounded louder and more full than with the port in..It actually sounded muffled each time i put it in
 
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