sonosub project, all hints and suggestions appreciated

station10fd

I started my sonosub project last week. With the Christmas present of a 15" titaninc, I'm on my way. I'll show my progess up to now, then I'll beg for hints and suggestions.

Here's a pile of oak lumber for the visible disks ready to be cut up. Inside disks will be made of MDF.


Made small pieces out of big pieces


Lining up the oak pieces for biscuits, dont want any showing around the edges.


Boards biscuited, glued, and clamped up.


Driver circle cut out


Test fit of the driver


Legs drilled and fitted with stain applied


Bottom plate drilled and stained for accepting driver plate legs


Now I'm at a point where I need to decide what I'm going to tune the sub at. Using the sonosub calculator, cutting the tube to 4', this is what I get.


I've read that tuning below 20hz will not gain me much of anything, between all the FS, xmax, vas, qts, and FU's, all of which I have no idea what the heck they mean, except for the last one, it's giving me a headache. So I guess I'm just asking you guys if I'm on the right track.

Once again, all hints, suggestions, and critiques apprecitated.

Mike T.

station10fd

I guess a little qualifier should have been added. This sub will be used mainly for home theater, when I listen to music, my current sub is turned off. I'm really looking for that "punch you in the chest" feeling with movies.

Mike T.

Systems

Wow very nice Mike.I have seen a bazillion sonosubs but can't remember any that didn't have just painted black end caps.The oak will really look good.

station10fd

GV#27 wrote: »

Wow very nice Mike.I have seen a bazillion sonosubs but can't remember any that didn't have just painted black end caps.The oak will really look good.

Well, when I first presented the idea of putting a sonosub in the living room to the lovely wife, she said "Your gonna put what in my living room?". Only after saying I'd dress it up a bit with some nice oak, did she agree with the project.

Mike T.

ben62670

I did one, and I went wit a little smaller volume with the same sub. It will sound best with a large volume around 9 cubic feet, and tuned to 15hz. You will lose a significant amount of power handling, but the deep bass is worth it. I ran 800 watts clean, and the cone over excursion will tear your sub up pretty quick. Don't run more than 500 watts to it, and it will live happily. I am using a 30" port for the flattest response. I also used sonosub.exe, and winisd. Sono doesn't give good calculations for frequency response, or power handling. I ended up having to make adjustments to get it right. If that driver is tuned to 20hz it will have a large peak around 35hz. Here is a link to my project. When done you will have a sub comparable to subs 3 times the price. Have fun, and enjoy.

http://www.polkaudio.com/forums/showthread.php?t=51533

station10fd

Ben, I cant count how many time's I've read your's and Dane's sono projects. I guess this is part of the fun, trying to figure out how to do it so it will sound good. I've been eyeballing ebay lately for an adcom 555 like you've been using, but the prices have gone crazy the last month. I'm kinda leaning to either the dayton 1000 watt rack mount, or the buttkicker 1000 watt amp. I figure I will have my mind made up by this weekend because I should have the project done in a week or so, and that would suck having the sono ready with nothing to drive it with.

Mike T.

ben62670

I really like the looks of the Dayton. They use a nice transformer instead of a switching power supply. The specs are very impressive, and it has a nice EQ feature to help match your room acoustics. With my sub a little smaller it is a little tighter, but with the larger volume it really digs deep. The output is tremendous, so don't worry about how much power as compared to how good the power is. I wish Dayton had a rack mount 500 watter for a build like this. I definitely recommend using a 30" port if you have the clearance from your sub to do this. You can always cut it shorter if need be, but I really had the best results large, or medium volume with the longer port.

Ben

station10fd

My port from thriller audio is supposed to be in tommorrow. I ordered 2 tubes at 12 inches each....add in the top and bottom flairs, that might yield me 27 or so inches. 27 plugged in my sonocalculator, with the casing still cut at 48 inches would give me 14.5hz with 11.8 ft. Looks like I've got some play room when I do start tuning. I appreciate your help ben!

Mike T.

ben62670

No problem. Check out WinIsd for calcs on excursion, and power handling. You really do have to tune down at 15hz to get it flat otherwise you end up with a decent bump around 40, and it drops off real quick at 20.

Keep us posted

Ben

station10fd

The port came in today, with both flares attatched, it's 30 inches, with just one, it's 27. I think I'll PM Dane, and ask him if he tried using the port with just one flare end instead of two, and if there was any difference. It'll be a lot easier adjusting port length with out having to remove the bottom flare. I think it's time to do some reading on excursions, power handling, flat spots, and dropping off..........sheez, I'm such a newbie...LOL. Thanks for your patience Ben.

ben62670

No problem. I spent way too much time relying on the computer, and learning the corrected numbers on the SPL meter, and not taking into account room gain. For me it wasn't a big deal. I have learned a lot from my mistakes, and am glad to share my experiences with others. It is a 6 inch port correct?
Ben

jakelm

The programs will get you close, but trust your ears. The room and yours ears are your friends, they will let you know when its right. Remeber you can always take away, so if your going to tweak the port, dont take away too much at one time.

BTW, very nice.... Always nice to see a DIY rump shaker....

station10fd

yes, 6 inch...........I'm getting excited, time to go cut the opening in the top cap

ben62670

jakelm wrote: »

The programs will get you close, but trust your ears. The room and yours ears are your friends, they will let you know when its right. Remeber you can always take away, so if your going to tweak the port, dont take away too much at one time.

BTW, very nice.... Always nice to see a DIY rump shaker....

+1
Jake helped me out with my project, and was there the whole way through(thanks Jake:)). Definitely don't cut that port till you figure out your SPL sweep, and do an in room correct chart. Radio shack has a nice digital meter for $50.

jakelm

No problem Ben...

Just be patient with it. Give it time to break in. I would leave the port as is for a few days, then measure. Then adjust and leave for a few more days. Most times, getting used to it is the biggest problem. If you have never had something like that before, get ready to have your socks nocked off....

Ben knows about the wattage factor, he might be adble to chime in more info on that, but I dont see a problem with 400-600 watts.

station10fd

Thanks guys, I'm trying not to rush things. I just tried to order the dayton 1000 watt rack mount amp, and their out of stock till Jan 27th...............SON OF A b@%w@#$@!!!

ben62670

Yeah with the wattage just keep your ears on what the sub is doing. With a sub like that you will have to set it at like -5-8db or it will over power your movies/music. What I ended up with is a 30" port in mine. I tried different length ports, and went back to the 30"er. For music a volume of 7 feet works best, but I have some monster speakers that don't need a sub so I will go back to 9 cubic foot tube. Like Jake said socks will be blown off, and you might want to wear your brown shorts:D Seriously:D:D

ben62670

station10fd wrote: »

Thanks guys, I'm trying not to rush things. I just tried to order the dayton 1000 watt rack mount amp, and their out of stock till Jan 27th...............SON OF A b@%w@#$@!!!

Check audiogon.com for a used GFA-555, and bridge it for 850 watts. Just be careful.

station10fd

ben62670 wrote: »

Like Jake said socks will be blown off, and you might want to wear your brown shorts:D Seriously:D:D

Now that's what I'm talking about!!!

station10fd

Got the top caps cut tonight. I did run into a problem that the smallest circle my circle cutting jig would cut was 9 inches, and I needed just better than 6 inches for the port. So, not wanting to spend any more money on stuff I'd only use once, I found the right sized socket, screwed it to the board, then just followed around it with the router. Worked pretty dang good. Staining the top cap tonight, the acoustic foam is supposed to be in tommorrow.

Mike T.

station10fd

Got the tube cut this morning, and put her together for a sneek peek.........my gawd this this is gonna sing "look at me". I hope the wife doesn't see this pic with the taco bella dog on it :eek:

Mike T.

station10fd

Ok, as I sit here looking at this thing, I'm wondering if it's too big, is there such a thing as too much volume, given the size of the 15" titanic? Right now the way it sits, it's volume is 13.41 cu. ft. If need be, it's no problem cutting the tube down right now.

Mike T.

steveinaz

You're from Texas and you're asking us if something is too big?

Say it ain't so man....:D

station10fd

steveinaz wrote: »

You're from Texas and you're asking us if something is too big?

Say it ain't so man....:D

That's some funny stuff right there Steve:D I'm not full blooded Texan, so maybe that has something to do with it.

ben62670

It won't handle much power like that. Its so huge its like free air:D You should be around 9 feet for HT, and 7 feet for tighter music. These numbers are effective volume. I will double check, and edit if I gave the wrong numbers.

Ben

I had the right numbers.
You are going to have to cut your tube to 41 inches to get the volume to 9 feet.
Your tube is 24" correct?
Thanks
Ben

jakelm

station10fd wrote: »

Ok, as I sit here looking at this thing, I'm wondering if it's too big, is there such a thing as too much volume, given the size of the 15" titanic? Right now the way it sits, it's volume is 13.41 cu. ft. If need be, it's no problem cutting the tube down right now.

Mike T.

A 15" sub doesnt need more than 9cuft. Just my opinion, but you have too much airspace. I would trim it down to at least 10cuft. Cutting about a foot off the top.

station10fd

Ahhhhhhhh Crap, I’m gonna have to cut a foot off of my tribute to manhood? That’s what I get for jumping into this without enough research. I guess if I would have gone with a smaller diameter tube, then I could have got the height I wanted, oh well live and learn.
My tube is actually 24.75 inside diameter. So going with 10 cu.ft. max, that should give me a tube length of almost 3.5 feet, plus the base and I’ll be looking at a total altitude of a little better than 4 ft. In actuality it will probably make the wife happier with something that doesn’t stick out so much..
Ben and Jake, you guys are life savers. Thanks for helping me through this.

Mike T

jakelm

24.75" Diameter, 37.5" H (which is 1 foot cut off top), should give you ~10.4 cuft. Which is what I would start with, using a 15" driver. It seems short because its so fat.

Port length tuned to 17Hz, using 6" port in a 10cuft enclosure, by my calculations, should be around 20".

15hz, port around 30"

ben62670

Trust me on this one. Keep your port at least 25 inches, and 9 feet is kinda big(never mind 10+!), but it will suffer in the power handling department. Also if you blow yours up(like I did(I should have taken pics!!!)), and they find out that you are using an enclosure larger than 6 feet they will not warranty it! I had to pay to replace mine after telling them what I had for dimensions.

jakelm

Edit...

station10fd

jakelm wrote: »

It seems short because its so fat.

Thanks Jake, I'll use that one of the wife tonight.

Ok, I'm off to cut it somwhere between 9 and 10 cu.ft. thanks again guys.

Mike T.