Double 19O.v2 18" Build thread

I'd say to tune that sub lower so you can enjoy the really low stuff.


You could compare with NeoDan's design at this link:

http://www.avsforum.com/avs-vb/showt...ht=easy+button

I would still lower the tune a bit. In fact I would a lot if you can. Down to say around 15 hz??? That's where I have mine using the same driver. If you're using for PA purposes you can always use the 30 hz filter that's available on the EP2500. That way you can get the best of both worlds.

You could always do multiple round ports and tune lower with them. Then plug one of the ports to get a higher tune for PA usage. This could be the best of both worlds.

Actually that would lower the tuning.

It is a good idea though.

Limitless Earth,

The one weakness I see in your box is the slot port could use a brace running down the entire center of it mouth to end. You could use this to brace the enclosure and also to have the ability to alter your tuning. Plug one side of the slot port up and drop the tuning low for HT and then for PA/music or whatever run both sides of it open with a little higher tune and more port area. You'd have to play with the port area/ length to get a good mix of tunes with both sides open and one side plugged.

Like this...but with only one port brace, not 2.















If you could chop your port down to a 30" length and increase the height to 3.5" while running a .75" brace/ divider down the center of it this would give you a tune of around 25hz for PA with the whole port open increasing sensitivity, power handling and punch and a tune of close to 18hz for HT by plugging one side. You should have good response down to 16hz in that config. It'll be a bit underported in HT mode , but not too bad really. The length that would be chopped off of the port will make up for increasing the port to 3.5" for the most part.

Just use closed cell foam cut to a rectangle slightly larger than the slot itself. This will effectively "close off" the port. It will not get blown out of the slot either. The friction of the foam will easily hold it in place.

If you were using PVC for ports, you could probably find a way to mount a 4" female screw adapter to the very back of one of the ports. That way you wouldn't see the threads when you were looking directly at the sub. Then you could simply make a longer plug with the male screw adapter on the end. Stick the long plug into the port and tighten.

You'd have to go to Lowes or HD and experiment a bit, but they have various sized screw caps and all that neat stuff to probably make it work.


Then again, if the ports were in back, you could just put the screw-in portion towards the outside of the port. Stuff it, and screw the cap on very easily. No one could see it.

Just a thought.

Foam could work. You could make a plug out of wood with thick weatherstripping on it, or you could just stuff the heck out if with a throw pillow or something. I'm sure you can come up with something.

Looking good so far. A friend of mine got the 15" version and it shipped in a nice wooden crate wrapped in that same cardboard box. I noticed the shipping weight of my 19ov.2 was less than the 16ov.2 and noticed that, while it was still packed well, it was received in stiff cardboard.

Are you just building one at a time or waiting for the next one to arrive? You will be glad that you decided on keeping the 15 hz tuning option, but I may have skipped over where you said the port diameter. Did you say that they will be slot ports or did you change your mind? Also a more fun question, is this your first real sub? What do you have now?

I'm looking forward to seeing how the ports turn out.

You may run into some port chuffing with the lower tuned port. I will run it when I get home, but I have a feeling you will get a lot of chuffing when it gets below 25-30 hz.

i'd be interested to know if your drivers measure to ed spec.

others have found their drivers to measure way off spec.

I've done something somewhat similar. I used an A5-350 for a while and then built two sonosubs with 19ov.2s pushed by an ep2500. I love them. Once you get your port and tuning figured out, I think you'll be pretty happy with your subs as well. Those drivers bang

I used the eD spec on mine and, at least tuning frequency, was only off by less than about a half db measured. Still sounds good with the eD specs. I wouldn't worry too much about the specs. The ones that I saw published somewhere else wouldn't even give a correct model anyway.

somebody posted anger and frustration that the measurements weren't anywhere close to what was published. among other things, qes popped from about .35 to about .50. that puts a lot of "flab" in the sound.

one man's opinion is only a signal to investigate further.

Not saying it doesn't have a difference in the overall sound, just that it won't really make a difference in his modeling. His finished product will still work. Something to say about the way that people measure too. Different software might give different specs when measured. It may have been Dan that measured the driver and gave the specs before. Not saying he is wrong, in fact he is probably dead on accurate as he has no reason to fluff his measurements. Anyone know which specs mktheater used when doing his?

Nice start!

I would read the bracing thread though. Your tiny little MDF braces make me nervous. I ripped all mine out of one enclosure. It was just too flimsy.
Try cutting it out of 2x2 (2x4 cut in half) or something similar that is rigid, like 7 ply birchwood. This is just my opinion.

Here is the bracing thread:

http://www.avsforum.com/avs-vb/showthread.php?t=1155848

Also, I always cut the bracing AFTER I get four enclosure sides put together, because sometimes the lengths may not match up, unless you're really good at cutting wood to exact measurements (less than 1/16", I'm no pro).

Interesting article. The one thing I didn't like, is he says 18mm 7 ply is heavier than 18mm MDF. But all the 7 ply I've ever used was much lighter than MDF.
I had no idea that doubling up on thickness equates to making the panel 8 times stiffer. Not sure I can trust that though, based on his weight comments. Did I misread the article maybe?