or Connect
AVS › AVS Forum › Audio › DIY Speakers and Subs › jbl w15gti mkii and 15 lms-r?
New Posts  All Forums:Forum Nav:

jbl w15gti mkii and 15 lms-r?

post #1 of 12
Thread Starter 
So I got my 15" lms-r up and running on the ep4000.. I have it hooked up to a pioneer VSX-1021-K receiver. The sub is in a ~6 cu foot box with 2 4x24" ports. Lowes cut the wood and I put it all together.. It was a fun project actually...

So the results are mixed.. the sub is massive and I can rattle stuff like crazy on the first floor of the house. This setup is in the basement and while it sounds pretty good it doesn't sound incredible.. The door at the top of the basements steps physically moves when I have it pegged (not clipping but a bit below). I have used the built-in eq setup in the pioneer.. not sure if it makes a huge difference. So I'm guessing I have a few odd nodes in the basement. Leads me to where I am right now...

I was modelling the jbl w15gti mkii and in a similar 6 cu foot box with 2 24" ports (tuned to around 20 Hz) and with less wattage it seems to achieve a bit more (guessing cause of the sensitivity).. So I was thinking instead of buying another matching LMS-R 15" I'd go with the JBL w15gti and buy a factory refurbed crown xls 1500.

Any thoughts? Should I just get a matching lms-r or try out the JBL (I'd build the same box regardless). The only negative is the dustcap on the JBL.. not a fan frown.gif

thanks,
Mike
post #2 of 12
Sure. They are both very nice drivers.

What is it exactly that you are not happy with wrt the LMS-r? With a single sub, it's easy to get a rocky response at the seat. Have you taken any measurements to see what your frequency response looks like at the seat? If so and it's good ...maybe you just desire more SPL. biggrin.gif It happens to all of us. wink.gif
post #3 of 12
Thread Starter 
I wouldn't say I'm not happy with it.. it is an impressive driver.. fun screwing the motor on when the wrench is metal, heh.. I thought coming from 2 12's the 1 15 would be good enough.. And I think it was a massive upgrade considering that I put the 2 12's back in place and it sounded like something major was missing. Sort of like driving a good car and then going to a smooth v8.. You think wow, that was a nice upgrade.. little do you realize when you go back to your normal car just how much more the v8 is/was..

I wouldn't say a 6 cu foot box is huge but it does kind of limit placement.. plus the box with bracing has to weigh close to 150 pounds so moving it just isn't fun smile.gif So rather than tryin to find a sweet spot I was just going to add another 15" sub. (plus there arent many places I'd like to even try anyways).

My setup is I have a projector and a homemade screen.. I have klipsch rb-61's up front .. and then I have center channel on a small stand in the middle.. the sub is in the middle left, between the left front and center channels. Unfortunately I can't put the center channel on the sub as it would be in front of the screen then...

Would buying a radioshack meter be good enough to tune with? I think I enjoyed building the box enough that I wanna build another one.. I would have NO problem buying another LMS-R but just wanted to see if buying something else would be any benefit... (aka enjoying the hobby the most I can...)

It looks like when I modeled the JBL winISD says I would get around 5 to 6 db more over the 15" lms-r with less wattage...
Edited by mikeciccarelli - 6/25/12 at 7:12pm
post #4 of 12
Before deciding what path to take, you need to know where you stand..... you may have someone close enough to you with a laptop that is fluent in measurement with RoomEq Wizard to help you out. There may be a bunch of issues, especially with the crossover to the mains. ( bookshelves )

I would post your location, and ask if there is anyone around that could help you out..... you never know, some of us AVS'rs will work for beer n' burgers. tongue.gif
post #5 of 12
no reason to have "matching" subs and that ugly arse dustcap can be spray painted black if you are careful. :-)

mr. hurd's post is worth taking to heart. if you don't know what you have, how can you know what to improve?
Edited by LTD02 - 6/26/12 at 9:31pm
post #6 of 12
Thread Starter 
I bought the cheaper $50 Radio Shack meter.. it is a newer model and I do not believe they have a cal file for it.. I was playing around with room eq last night a bit on my laptop. I think I was able to get some measurements.. What files would you guys need to look at? Overall it seemed like 0 to 10 Hz varied quite a bit and then from 20 to 40 it dropped off quite a bit.. My box is tuned to 20 hz...

Last night I was doing some 20 Hz tests and such and it is just so weird in my basement... I'm sitting maybe 8-12 feet in front of the sub and it sounds "ok" but if I walk up the stairs to the first floor the door to the basement/first floor is shaking and the bass sounds so good.. I wonder if the projector screen (which I made and is behind the sub hanging on the wall) is canceling the bass or what.. something is either cancelling it or redirecting it.

I guess I just really, really need to move the sub to a different location in the room.. If I put in on the wall to the left of the seating position facing the stairwell I hear it even less (even though the sub is closer). I was hoping to keep it in the front as it is "away" from people and traffic and looks the best there...

thanks,
Mike
post #7 of 12
Quote:
Originally Posted by michael hurd View Post

Before deciding what path to take, you need to know where you stand..... you may have someone close enough to you with a laptop that is fluent in measurement with RoomEq Wizard to help you out. There may be a bunch of issues, especially with the crossover to the mains. ( bookshelves )
I would post your location, and ask if there is anyone around that could help you out..... you never know, some of us AVS'rs will work for beer n' burgers. tongue.gif

Who is near Loomis, CA, just outside Sacramento?
post #8 of 12
"Last night I was doing some 20 Hz tests and such and it is just so weird in my basement... I'm sitting maybe 8-12 feet in front of the sub and it sounds "ok" but if I walk up the stairs to the first floor the door to the basement/first floor is shaking and the bass sounds so good."

that is normal. play some sine waves of different frequencies (not at full blast!) and take your meter on a walk around the room, that might reveal some things...

also, the shack meter is notoriously inaccurate as you start to go much below 20hz or so.
post #9 of 12
Like these other guys have said, get measurements of your system. If you are playing your system within its limits, everything you need to know will be in the measurements. Once you get these measurements, post them up.
post #10 of 12
Hi All,

Sorry to 'hijack / resurrect' an oldish thread but need some help and after a lot of Goggling this is probably the best place to ask the question.

I already got the amp 'inuke 6000' and required materials to build a dual opposed 15 sub. Internal box volume without any stuffing will be close to 226 litres / 8 cu ft.
Sadly however PE seems to be out of stock of LMS R-15 for ages now. I just checked and they 'hopefully' will be in stock first week of March but no doubt that could change.
Stock of the W15GTi MKII - JBL 15 off Amazon does not seem to be an issue.

I've modelled both in WinISD but not 100% sure of the JBL T/S parameters and what the sound difference would be like in an HT environment.
Pretty much 100% movies playing between 90 an 100db total system volume in room.
The JBL in WinISD seems to be able to play much louder at all frequencies compared to the LMS.

Can someone please check my WinISD and secondly can someone comment on the SQ in the 10-80Hz region between the two.

Dual LMS-R 15
Box - 226 L
Signal - 1500W
QTC - 0.657
Cone Excursion safe to 5Hz

Dual JBL 15
Box - 226 L
Signal - 1000W
QTC - 0.8
Cone Excursion safe to 5Hz

JBL (Stuffed Box - assume 20% 'volume increase')
Box - 270 L
Signal - 900W
QTC - 0.776
Cone Excursion safe to 5Hz

Plan on running each driver at 4Ohm off a dedicated channel on the inuke 6k.

post #11 of 12
Thread Starter 
I'd be slightly cautious where you buy the JBL's from and who the seller is... I had a hard time finding any from "reputable" sellers.. maybe I was just being too picky and you might be fine.. I checked amazon and it doesn't appear as though amazon is selling them directly.. it is through a 3rd party..

The end story is I bought another 15 LMS-R.. and then I bought a 18 Dayton.. Since they got them back in stock I bought yet another 18 Dayton yesterday. If you are only going for movies the LMS-R is a serious beast... Music I find it lacks quite a bit above ~60 Hz. I really went into this going for movies.. but I ended up listening to a bunch of music as well (only so much downtime to watch movies but music I have more time for).. Only putting this here because you specified 100% movies..

I find that the layout and seating position in my basement flat out stinks and I'm limited on placement. I wish I could give you more insight to the JBLs other than they seemed hard to come by brand new from a JBL authorized seller.. I went as far as contacting PE to see if they could special order some. I guess their JBL rep didn't have access to these subs, only the PRO-Audio stuff.

If you end up getting them definitely post here with the results... I'd be interested to know still as the motor on them is very interesting.

Mike
post #12 of 12
Quote:
Originally Posted by mikeciccarelli View Post

The end story is I bought another 15 LMS-R.. and then I bought a 18 Dayton.. Since they got them back in stock I bought yet another 18 Dayton yesterday. If you are only going for movies the LMS-R is a serious beast... Music I find it lacks quite a bit above ~60 Hz.

I find that the layout and seating position in my basement flat out stinks and I'm limited on placement.

Mike,

Perhaps a bit too late now but the additional outlay might have been better spent on one of these per sub:

http://www.dspeaker.com/en/products/anti-mode-8033.shtml

If any subs are located close to each other (less than a quarter wavelength of your low pass frequency) and mono you can get away with one unit for those.

These won't solve any problems you have with dips but if your four subs are spread out in the room, there is a great chance they will fill and complement each nicely (check Geddes white paper on multiple subwoofers).

Auto-EQ using REW and miniDSP is another option but is definitely more work. On that last note, if you want to take integration to the next level, look into Audiolense or Acourate, but be prepared to fiddle... a lot!

And of course, if you have the space for a couple of bass traps (do you with monster woofers in the room?? smile.gif), that will make a nice difference too. The easiest DIY route here is a couple of Super Chunks corner bass traps - google!
Edited by NiToNi - 5/28/13 at 2:26am
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: DIY Speakers and Subs
AVS › AVS Forum › Audio › DIY Speakers and Subs › jbl w15gti mkii and 15 lms-r?