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j20056
09-24-2006, 12:48 PM
I moved to a new house, and I have a music room above the garage. The room is about 18" x 13" with a wooden floor, mirrors on all walls (It used to be a dance studio) and an irregular shaped roof with a lot of angles.
I can afford to have the room redone in a way that would maximize the quality of my audio system.
Question 1: Should the 4350's be elevated, or be put on the floor? Does it make a big difference?
Question 2: Am I supposed to put carpet on the floor to avoid the reflections from the wooden floor? Right now, the room is incredibly bright, with enormous amounts of reflection everywhere.
Question 3: I will most definitely remove all the mirrors from the walls. Is there a special wall treatment that I should apply, or anything will do?

Thanks

My system: JBL 4350's bi-amped with Max Intosh C38 Preamp, Mac Intosh 7300 2x300W Bass, Mac Intosh 7150 2x150 Mid-Highs, Wadia CD player

Mr. Widget
09-24-2006, 03:08 PM
If you can, you should elevate them and soffit mount them.

http://audioheritage.org/vbulletin/showpost.php?p=106445&postcount=7

http://audioheritage.org/vbulletin/showpost.php?p=125578&postcount=10

I would at least cover the side walls with floor to ceiling drapes to reduce reflections (there are more costly alternatives, but drapes look nice are easy to hang and do a very good job)... carpet the floor, and possibly install bass traps in the rear corners... You could make a stellar listening room out of this space.

Widget

Titanium Dome
09-24-2006, 04:00 PM
(snip)an irregular shaped roof with a lot of angles.


Can you describe this a little better?

1) How high is the ceiling at the sidewalls?
2) How high is the ceiling at its highest point?
3) Is the ceiling flat at the top or does it have a gable?
4) What's on the ceiling now?

Rolf
09-24-2006, 11:40 PM
I agree with Widget, and the bass traps you can make yourself, after you find out where in the frequency range the trouble is. Buying bass traps can be very expensive.

j20056
09-27-2006, 05:11 PM
Titanium:
1) How high is the ceiling at the sidewalls? IT'S A RECTANGULAR ROOM, BUT WITH ANGLED CEILING. SORT OF LIKE A PYRAMID SHAPE IN THE MIDDLE. AT THE SIDEWALLS, BEFORE THE SLANT START (45 DEGREE SLANT) THE HEIGHT IS ABOUT 6FT.
2) How high is the ceiling at its highest point? ABOUT 16FT BUT NARROW ON THE TOP
3) Is the ceiling flat at the top or does it have a gable? LIKE A PYRAMID ON THE TOP
4) What's on the ceiling now? NOTHING JUST SHEETROCK

I HAVE A DECENT BUDGET FOR THIS, SO I CAN DO THE RIGHT THING, WELL, IF IT'S UNDER 10K THAT IS. I CAN POST A PHOTO OF THE ROOM IF THIS HELPS.

j20056
09-27-2006, 05:14 PM
Mr widget,

that's really elevated... Don't you lose bass response if the woofers are so high up? I was thinking of raising my 4350's by maybe 10-15" at the most.
Besides, what will I gain by raising them by 15" versus straight on the floor?

Robh3606
09-27-2006, 08:50 PM
Hello j20056

If you rasie them up 10-15" you loose some mudiness in the mid bass. At the really low frequencies it won't matter a whit. I have my 4344's on 12" stands and they do sound better. The 4350 were made to be sofit mounted and have hardware to hang them on the bottom of the cabinet. One thing you need to consider is the 2405 and midrange horn. You want the 2405 to be close to the seated height of your ears. The 2405 is very directional in the vertical axis. Take a look in the Library at the polar plots and you can see. If you have them over head they can be angled down to center the pair on your prime spot. Basically you would mount them slot down or upside down. If you keep them floor mounted it would help if you had the stands/temporary dollies set up so the 2405's are at the same height as your head when seated . All you have to do is take a tape measure and see what make sense to you in your room. Ceiling or Floor the speaker doesn't care which boundry you choose. In a studio you have console/mixing board and widow into the studio to worry about but not at home. If you have them on dollies set at the proper height you can try positioning them in the room. You can't just wing it. You may want to consider a professional installer but give it a whirl first. If you have trouble reading these attachments send me a PM and I will email you higher resolution scans.

Rob:)

Mr. Widget
09-28-2006, 12:41 AM
Besides, what will I gain by raising them by 15" versus straight on the floor?Basically what Rob said... while Paul Klipsch was an advocate of boundary reinforcement, he wasn't as concerned with accurate reproduction as many thought he should be. If you soffit mount these large monitors their response will smooth out considerably... as they will be mounted as they were originally intended to be.

I couldn't find an image of a pair of 4350s in use... they have been removed from most of the studios they once lived in, but here are some soffit mounted custom JBLs... I have heard this system. There is no lack of bass. From this picture it looks like they may get reinforcement from the ceiling... not so. There is no ceiling near them. The fabric hides a large bass trap.


Widget

Titanium Dome
09-28-2006, 10:54 AM
When you figure the 6' sidewalls and the 16' high pyramid shaped ceiling, soffit mounting is not a simple or straightforward matter. Above the 6' level there's about 780 cubic ft. of pyramidal space bounded by a reflective surface of approximately 310 sq. ft.

Mr. Widget
09-28-2006, 11:01 AM
When you figure the 6' sidewalls and the 16' high pyramid shaped ceiling, soffit mounting is not a simple or straightforward matter.So? Life is hard. :banghead:

In the photo I posted the actual ceiling is something like 15' above the apparent ceiling.


Widget

Titanium Dome
09-28-2006, 11:59 AM
So? Life is hard. :banghead:

In the photo I posted the actual ceiling is something like 15' above the apparent ceiling.


Widget

I'm only guessing here, but I think the room you posted was planned as a purpose-built audio space. I'm not guessing when I state that j20056's room is not. It's not even a normal box-shaped room.

I'm sure it will be a great listening room when he's done, but soffit mounting sounds like a traditional answer to a nontraditional situation. Technically, there is no soffit in that room (w/ bass trap, acoustical treatment or otherwise), so I think it's prudent to really think about it before he goes to the trouble of mounting them.

Ken Pachkowsky' s dealt with a nontraditional room out at Palm Desert where he had his Westlakes. He did a ton of tweaking to get it right, though he didn't have the option of doing a lot of room mods.

In this case, j20056 (got a name instead of a number? ;) ) has the chance to do the room right, and it's a challenging room. Slightly more than 1/3 of the room's volume and 2/5 of its surface area are above that 6' line.

It might be as simple as dropping in an acoustical barrier at the 9' level or something. That coupled with your excellent draping advice could help immensely.

Titanium Dome
09-28-2006, 12:02 PM
For your entertainment:

Titanium Dome
09-28-2006, 12:04 PM
If you can't get enough volume, double up.

Titanium Dome
09-28-2006, 12:06 PM
Two can play that double game.

Mr. Widget
09-28-2006, 12:27 PM
Technically, there is no soffit in that room (w/ bass trap, acoustical treatment or otherwise), so I think it's prudent to really think about it before he goes to the trouble of mounting them.
I assumed from the outset that this thread was about designing a listening space.

His space is large enough that if his goal is to have a "purpose built" room for audio, he can build it into that space. I agree that building into that space will be a challenge, but I can imagine it working out very nicely.



Widget

Rolf
09-28-2006, 01:23 PM
If you can't get enough volume, double up.

Hi TD. On the left of the double 4350's, is it an AR LST?

For many years ago it was one of my dream speakers. (D'oh)

John W
09-28-2006, 01:26 PM
Where do you put your super-heroes if you mount them in soffits? :blink:

Titanium Dome
09-28-2006, 01:54 PM
Hi TD. On the left of the double 4350's, is it an AR LST?

For many years ago it was one of my dream speakers. (D'oh)


I was thinking the same thing, BUT all the AR LSTs I've ever seen had white or light colored grille cloth, and they also had the logo on the right of the front panel and an L-pad on the left of the front panel.

This speaker has dark cloth, and it seems to have the logo at the center bottom with no L-pad. :dont-know

j20056
09-30-2006, 12:25 PM
Hi. Here are three photos. The first one shows the south wall, where the white 4350's are going to be setup as a listening stereo system, and possibly mixing. The second photo is the north wall, where my workstation for mixing and editing is, including the Genelec nearfield monitors. I also have a pair of Black PA JBL for band practise, but disregard that. Also, I will have a stero pair of Marshall cabinets with 4x12's for my guitar system, which I think I will mount above the JBL PA speakers. Lastly, the third photo shows the ceiling. I used I wide angle, so i think it makes the ceiling look a little bigger than it really is.
So please let me know what you guys think. As I said, I'm thinking a fairly neutral room, because I don't need a super bright for recording as I like to add reverb and delay via plugins.
Also, and importantly, should I setup a curtain on the north wall that would go across the entire wall and hide all the recording gear and genelec/jbl/marshall cabs for both aestethics and to remove the rflections from the 4350's facing on the other wall when I'm in listening mode?

jack_bouska
10-04-2006, 07:53 AM
Sorry, no time to write a detailed post right now (I'm "busy" at a convention in New Orleans), but I will get back in a week or so with some thoughts. In the mean time, please measure and post the exact dimensions of the room. If you could sketch floor plan, and annotate the various widths, depths, and average height that would be very helpful for analysis.

In the mean time, if you want to do some additional reading, please feel free to have a look at an article that I wrote for our London HiFi club a few years ago. One of the members posted a similar question on building a dedicated listening room, and so I wrote up a short article documenting my own experience designing a listening space back in Calgary.
link is:
http://jgbouska.tripod.com/audio/ (http://jgbouska.tripod.com/audio/)
Specifically:
http://jgbouska.tripod.com/audio/room_design.pdf


More later, Jack Bouska

NancyJ
10-04-2006, 04:51 PM
somebody.. someone.. find him a mike and measure the room.
well sounds good to me. are those wx due to the white thing?
what? do you have the active crossovers i need for yours??

This is more fun than i could ever imagined. ;)

audition
10-06-2006, 12:18 AM
:blink:

Storm
10-06-2006, 12:38 AM
What on earth made this guy do this?

I could not handle looking up that high to view such a small television.

:biting:

Zilch
10-06-2006, 02:23 AM
What on earth made this guy do this?I was gonna say "Adolescence," but there's just one mid, VHF and UHF per side.... :thmbsup:

[And all them woofs're in phase, we presume.... :bouncy: ]

SJOSTRAND
10-06-2006, 04:58 AM
Is that what they call a wall of sound ??:)

Titanium Dome
10-06-2006, 09:38 AM
Is that what they call a wall of sound ??:)

Maybe more like a "wall of confusion" (apologies to the Temptations and Ball of Confusion) or a "power of babel" (apologies to Moses, author, and the builders of the Tower of Babel). :p

Zilch
10-06-2006, 10:58 AM
Is that what they call a wall of sound ??:)Yup.

Unlike most, this one is well executed. :applaud:

[The "sound" part, at least....]

Rolf
10-06-2006, 06:16 PM
SCHROMPHHH:applaud: :blink: :banghead: