Sonosub Build, wife is going to be really happy!

[Cind3r]

Hi all,
After reading many a build thread and countless articles I finally decided to build a sonosub. My hats off to Steve Callas and ssabripo (Lord of Bass) and many others that share their experiences so we all can learn.

I am basically going to copy what Bill3 did here a while back, except my tube is going to be a little taller.
I got a 30" tube @ 72" tall, 8" port about 31" long in sonotube for about a 12hz tune at about 749l. hopefully a Q18 will be here in the next few days. I plan on powering this with an EP2500 that I will be ordering later on this week. I would like a little input on the tune if you guys think its to low. I modeled it a little and from my limited understanding of WinsISD I should be OK. Input always welcome.

I probably wont get to start on my endcaps till this weekend where I will try and post some pics of my progress.

*Edit* I changed the size to 68" tall and a port length of 30" for ~13HZ and ~700L

[Mike P.]

The advantage of tuning that low is you probably won't need a High Pass Filter. The disadvantage is you're giving up a lot of SPL from 14 hz and up compared to a 16 hz tuning with a HPF at 15 hz.

[Cind3r]

exactly the input I was looking for, thanks for pointing that out. I was mainly looking at excursion and not so much SPL.

Thanks

[Bill 3]

So your wife likes a lot of

[Cind3r]

Well I am trying to be a little sarcastic but its one of those things where I always have a few projects going on and I started to describe this one and she went back to watching TV mumbling something like whatever...

Whelp it got her attention when she pulled in the garage and saw this

[Bill 3]

Where's the other one?

Not sure if this will help, but I have a lot of room gain around the 10Hz area. I can't remember if I have any graphs posted here, but I will try and get some up for you to look at. My room is in the basement with concrete floor, approx 4000 sq.ft.. Pool table, pub tables and chairs, sofas, etc. -not a dedicated theater room and no room treatments.

[Mike P.]

If the tube is 72" tall, subtract 1.5 for the endcaps = 70.5". That's an internal volume of 817 liters. You'll have yo do some calculations for the port length to get a 16 hz tuning after all subtractions are done. Or cut the tube down so the final net volume is 750 liters.

[Cind3r]

I was mainly going to go off of sonosub.exe numbers for a port length. Actually my thought was to make the port a little long to give me some room to experiment.

Another queston I have is I plan on using an 8" port, but would there be any advantage or disadvantage in using a 10"er?

Thanks for the comments and I would appreciate any graphs you have if its not to much trouble. I need to brush up in my REW before I get this thing done.

[Mike P.]

Yup, sonosub.exe is the way to go, it makes it so easy with all the lengths figured out for you. The advantage of a 10 inch port is lower air speed, the disadvantage is longer port length which is only a problem if there isn't enough room between the end of the port and the back of the sub. Graphs are no trouble, which ones do you want?

[Cind3r]

Yes I agree that it is such a kewl program

In your opinion, what would you go with an 8" or a 10" I would like to add that I plan on using a flare on both ends no matter what diameter I use.

My responce about graphs was directed to Bill about some in room measurements that he was going to try and dig up, I should have worded that better sorry for the confusion.

[Bill 3]

WinISD gave me the following graph for 750watts.



My in room response at my seating location resulted in this graph. No EQing with BFD, but maybe audyssey, I can't remember.

[Cind3r]

Interesting how similar the graphs are from modeling to inroom

Man you do have some room gain going on!

[SturmMD]

That 10dB room gain peak at about 11Hz must sound incredible. It looks like the response drop from 30hz down is perfectly compensated by room gain.

[Fi Audio]

EP2500 will have tons of headroom. I'm assuming that you purchased a Q18 D2, as I haven't seen any requests recently for single coil drivers for HT.

Not a ton of WAF with the audio water heater, but I haven't met anyone that didn't enjoy the visceral experience of a monster low tuned HT sub either.

Definitely keep us posted!

Thanks,
Scott

[Cind3r]

Yes you are correct that I ordered the Q18 D2 (you had me worried, I had to go back and check)
Looking at pricing the EP2500 isn't that much more than a EP1500. With all the success on these forums I thought what the and plus it will give me some headroom in case I want to expand later on.

The wife already thinks im crazy so this project fits right in.

Thanks Steve

[SteveCallas]

30" diameter and 72" tall - I'm not seeing too much advantage in going any larger than us other crazy folk at around 650 liters. And to nitpick, since you are going for a single sub, I'd tune a bit higher than 12hz to achieve a better balance between headroom and extension.

Otherwise, more power to you

[Cind3r]

Sorry I have not posted in a while, things have been a little crazy lately.

I have been slowly working on it, I got the top encap cut and glued together. The Q18 showed up last week so hopefully I will get the bottom endcap cut and glued up this weekend plus the EP2500 should be delivered today...give me something to play with.

I am still deciding on a final tune, with everyones input I am thinking of something around 14hz-15hz. I am trying to tune it so I will not need a HPF. I plan on keepin it at 72" so I can get some inroom measurements then wack some off the top and remeasure to see what happens.

thanks for the input and I will get some pics up tonight

[Cind3r]

Alright, scratch that about keeping it at 72" I spent some time reviewing some other build threads and caught an entry from Steve Callas that there seems to be a sweetspot of 650l tuned to 13hz. so looks like I will cutting my tube at 64".

I do have a question though - Sonosub.exe shows my port at 33" but WinISD shows 32" for a 13hz tune? Or am I being overly critical?

[Mike P.]

One inch won't make any noticeable difference, flared ports are one inch longer then non flared ports for the the same tuning frequency.

[Cind3r]

One inch won't make any noticeable difference, flared ports are one inch longer then non flared ports for the the same tuning frequency.

Thanks Mike I figured it wouldn't make much diff but you never know.

I commented that my Q18 got delivered last week and I wanted to give some feedback that the box was pretty beat-up but thanks to the excellent packing the sub is in perfect shape. Thanks Scott at Fi Audio

Shortly after I picked up the tube and port


We used respirators and eye protection but as everyone knows it's hard to talk with those on and this was between cuts so don't flame me.


Fan mod completed on EP2500


Couple endcaps, hopefully getting the rest done this weekend


You hear it in just about every thread but holy cow was I shocked when I pulled this out of the box

[Mike P.]

Be aware there is a transparent release film on the inside of the sonotube that glue won't stick to. You'll have it peel it off before you attempt to glue the end caps to the tube.

[goonstopher]

Mike, do all tubes have it?

I tried to pull off a little piece and it takes some paper with it no matter how careful I am. Do you take it off the whole tube or just the top? Will spray tack stick to it for the batting?

[Mike P.]

Depending on what brand of tube you have, with some just the film peels off, with others some paper comes off as well which is not a problem. On mine I peeled the whole tube.

[Cind3r]

Already done but thanks for the reminder

I went ahead with the whole tube and I had some paper come off with it as well but not enough to worry about

[SteveCallas]

Well look at that

Yours




Mine