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View Full Version : New Room for 4350's: Photos



j20056
10-01-2006, 04:32 AM
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?

j20056
10-02-2006, 04:43 PM
I was hoping for some comments and suggestions on how to treat the room, especially the ceiling. Please...

Robh3606
10-02-2006, 05:07 PM
First thing first have you tried them??? Second who painted them white:banghead: Sorry I had to ask;) if it was you don't tell us:p I will give it a shot. You are in the upstairs if a house in a room with 2 gabled windows one flat wall and the other 3 sides broken up with the gables and crawl spaces. You have your mixing gear at the other end close to the back wall. Those speakers will beat you to death with you mixing gear that close to that wall. You definitely need to get the mixing gear more into the room and the speakers off the floor. As far as the rest of it??? Why don't you see if you can get them to sound reasonably balanced in the room. It's going to be real live with those hardwood floors. Can you get a couple of rugs in the room to help deaden it a bit?? Those crawl spaces and such might work to you advantage. You may be able to open them up and get good sized bass traps into them. Do you have a friend with an RTA or some kind of measurement gear???? Unless you hire someone you need to get an idea what's going on so you should have access to some kind of measuring gear.

Rob:)

Rusnzha
10-02-2006, 05:13 PM
The angles will give you a real advantage. Try sound absorption materials opposite your main speakers and behind them. I'm using the 2 foot colored squares from parts express and getting good results.

http://www.partsexpress.com/webpage.cfm?&DID=7&WebPage_ID=3&manufacturer=34&sm=2&so=1&filter=pyramid

oznob
10-02-2006, 06:13 PM
I have always dreamed of having a room like that! Looks like a great project.:applaud: Please keep us posted on your progress.
Rob, I'm sure the white is just primer for the JBL blue to follow!;)

grumpy
10-02-2006, 06:28 PM
Thinking you might want a symmetric launch point... e.g., from against the
wall with the door or vice versa? so you start with symmetric bass problems :)
(may not be possible... but worth thinking about). Nice to have such problems ;) -grumpy

j20056
10-04-2006, 05:13 AM
Thanks guys. I bought these speakers so beat up that I had to refinish the cabs. Believe or not, when I got those 13y ago, there was no internet and no bloody information at all about the speakers, so I had no idea that they were originally blue. The finish was ugly grey on the outside, and beat up gray with stains on the front. The drivers all needed to be recoiled. Luckily, I owned a pair of 2405's which I nicely fit in there so I have dual tweeters. Initially, I did them all balck since I didn't know better. Later on, I bought a super modern house with white walls and lots of colors, and the white finish actually made sense at the time. I now am considering redoing them a third time, and I absolutely *love* the white birch natural finish of the new DD66000's. I'm afraid I actually don't find the original blue attractive. frankly, these are my speakers, and I will own them for life FOR SURE, so I don't really care about the vintage factor or the retail value. Cranked with bi-amped SS MacIntosh's, they sound as good as blue ones. Sorry for being radical.
Now, can you guys recommend a consultant in Connecticut? I want to do this right, so I don't mind shelling some money. Also, does a high-quality parametric EQ make sense? Which ones are good in the under $3,000 range?

Dreamcatcher
10-04-2006, 06:18 AM
Woow! this is very very very mice one!

Chas
10-04-2006, 06:28 AM
Dual tweets? I don't mean to be a party pooper here, but if you have paralleled the 2405's and kept the original 3107 crossover there will be a shift in the frequency of the high pass cutoff.

You might want to consider going back to a single or perhaps make them selectable.

John
10-04-2006, 11:39 AM
Those sound like they were the studio grey units from birth and not the walnut veneered units with blue baffles. What is the front profile like at the front of those cabinets? Is it beveled or square? If it is square it was the studio grey model.

Zilch
10-04-2006, 11:42 AM
You might want to consider going back to a single or perhaps make them selectable.Agreed. You've got interference comb filtering galore running both concurrently.... :o:

John
10-04-2006, 12:10 PM
You've got interference comb filtering galore running both concurrently.... :o:

So it will sound like a actual live arena show when cranked:applaud:

Zilch
10-04-2006, 12:22 PM
So it will sound like a actual live arena show when cranked:applaud:A primary reason JBL leads in SR is that they pay VERY explicit attention to that stuff.

The techinical documentation of arrays on the JBL Pro website is interesting reading in this regard.

Also, that on cinema, and the SR application guides.

[It ain't trivial.... ;) ]

j20056
10-04-2006, 05:03 PM
You guys know your stuff... They are indeed square on the front, so I guess they are the studio grey units. Well, the grey was pretty ugly, especially when damaged I can tell you. Is there a difference between those and the blue ones?
Going back to this dual tweeter thing, is the only reason why there are two holes so that you can mount them on either side, but *not* both?
I don't believe the passive filters were changed internally, so they must be indeed 3107. I added the second tweeter at the advice of a pro sound installer form NY who sold me and installed the system. I thought he knew what he was doing on this particular point. As far as amps, I use them bi-amped with an active JBL crossover between my pre and the two power amps (All MacIntosh SS). How am I supposed to hear the "comb filtering galore"? Is it mostly affecting the high end, or the entire spectrum? I mean, the system sounds really great, so I never noticed, but if it would improve the system to only use one (and I like the suggestion of putting a switch to use or the other, and see what sounds better) then I would consider it. But how do I detect the comb effect by listening?
Looks like I am going to put microsuede on the walls, over a layer of Owens-Corning 703. Do you guys think it'll soften too much? Is the Owens Corning for sound insulation, or for anti-reflection (or both)? I do not need at all the room to be insulated, no neighbors. What do you think?

Zilch
10-04-2006, 08:18 PM
How am I supposed to hear the "comb filtering galore"? Is it mostly affecting the high end, or the entire spectrum?Play pink or white noise through the system, and move side to side. You'll hear it "swishing" in the high frequencies as your ear moves between reinforcement peaks. The space between peaks is different for different wavelengths.

What's that mean? There's no position where it's accurately reproducing all frequencies present in the program material, except in the vertical plane precisely on the centerline between the two tweeters, perpendicular to the baffle, where you are equidistant from both of them.

Why does it matter? Aside from the inaccuracy, there's little hope for decent imaging if different portions of the same sound appear to originate from different locations. A single coherent source is requisite.

Can you aim them at the listening position and have that work? Yup, but only at one location, the vertical line in space where the planes intersect. Headphones are more convenient; at least you can move a bit with them.... :p

Robh3606
10-04-2006, 09:14 PM
How am I supposed to hear the "comb filtering galore"? Is it mostly affecting the high end, or the entire spectrum? I mean, the system sounds really great, so I never noticed, but if it would improve the system to only use one (and I like the suggestion of putting a switch to use or the other, and see what sounds better) then I would consider it. But how do I detect the comb effect by listening?

You may not. If you look at the on axis response of a 4344,4345 AND 4355 as well as a TOTL JBL 9800 system you can see the ripples in the response in the measurements. Hearing them is another issue entirely. I have 4344's and I will be damned if I can hear them even when compared with a system with much flatter response. The comb fitering is the ripples in the response between say 7-10K in the attached graph.

http://audioheritage.org/vbulletin/showthread.php?t=10614

That's a 4355 which is identical to a 4350 in the region of interest. Those peaks and suck outs are with one 2405. With a pair it could mess your L/R imaging up a bit but could also splash some extra HF around the room and make them more open as well. Try the switch and see which you like best and leave it at that.


Looks like I am going to put microsuede on the walls, over a layer of Owens-Corning 703. Do you guys think it'll soften too much? Is the Owens Corning for sound insulation, or for anti-reflection (or both)? I do not need at all the room to be insulated, no neighbors. What do you think?

First off without being in the room whatever anybody has to say is hot air including me. Speaker placement is one thing you are talking room treatment. No one can give you any meaningful advice without hearing what they sound like in the room. It may take you a week or two just to get something as simple as the placement right. You change the acoustics by adding the panels and you may be back to square one. Yeah you can measure them and there are some basic guidelines and such but what counts is what you think and what's actually happening in that particular room. You can't look at some photo's and determine what type of panels to use and how many square feet and thickness you need to get the right balance of reflected sound and reverberatioin rate. If I posted pictures of my speaker placement you would would think I was nut's. The plain simple fact is that's what works in this room. You have a very complex room with all the angles and broken up walls with the gables. You can't just plug your room into some online calculator and get anything back that's going to work. You really should consider a pro for instalation but if you can't swing it don't do anything permanent until you are really sure it's going to work. Read as much as you can. There are a lot of talking heads on the internet in audio forums that sound good but really don't know a damn thing. This is one of the better forums because we have some real pro's here and still this is not the place to get some quick advice and start dropping some real cash based on the suggestions. You have to do your homework.

Rob:)

j20056
10-05-2006, 06:18 AM
Thanks. But even if I remove the extra 2405's from each speaker, why wouldn't I have the same issue (and all of us) given that there are still two tweeters in a stereo setup?

hjames
10-05-2006, 07:02 AM
Thanks. But even if I remove the extra 2405's from each speaker, why wouldn't I have the same issue (and all of us) given that there are still two tweeters in a stereo setup?

Because you are not feeding identical source information to both channels ...
Recording engineers have mixed the L/R channels differently - so the output is different.

It may also have to do with the wavelengths being pretty short above 10kHz

Zilch
10-05-2006, 12:27 PM
What Heather said.

It's what imaging "Sweet spot" is about....

j20056
10-05-2006, 05:43 PM
Do you guys know a good professional room installer in Connecticut near Stamford? I am quite willing to hire a pro, but I need to find someone reliable. Thanks.

grumpy
10-05-2006, 05:50 PM
might check http://www.cedia.net/ for custom installers...
not necessarily "sound room"-centric but you might find some
leads there.

-grumpy