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View Full Version : 4315's ? & vertical alignment



Akira
07-21-2005, 10:14 AM
you rarely read on this forum anything about 4315's...my favorite JBL. i have only had very limited exposure to them and they seem to have had a short production run...not very popular, yet many sound engineers swear they are the best. would love to trade my tannoy system12DMT's plus lots of $$$ for this speaker of similar value (4315) any opinions on this model?
the other thing that i have always pondered is JBL's reluctance to physically line up their drivers in a vertical line array. i would not try to second guess the designers at JBL--they have forgotten more than i will ever learn. but, this is totally sacrilegious to any live sound engineer. the only vertical array i can think of in the JBL lineup are the original L100's. you can totally hear a difference in phase coherency and imaging when compared to the other series of 4310/11/centuries. the only theory i can come up with is they are favoring a cluster design which works well in a near field position. still, it is my belief that a speaker 'floats' better when drivers are vertically aligned.

pmakres1
07-21-2005, 10:28 AM
...the only vertical array i can think of in the JBL lineup are the original L100's. you can totally hear a difference in phase coherency and imaging when compared to the other series of 4310/11/centuries. the only theory i can come up with is they are favoring a cluster design which works well in a near field position. still, it is my belief that a speaker 'floats' better when drivers are vertically aligned.

Take a look at the L220 and L300. There may be others that
have the drivers in vertical alignment, as well. The L220 also
features front to back ("acoustical alignment" according to JBL)
alignment.


Peter

(I have a pair of L220's that can be seen in my Avatar).

Akira
07-21-2005, 10:31 AM
yes i forgot about those models...do you feel a vertical alignment makes a difference?

pmakres1
07-21-2005, 10:33 AM
yes i forgot about those models...do you feel a vertical alignment makes a difference?

Yes I do, as well as the front to back alignment of the L220 provides terrific
depth of image.

Akira
07-21-2005, 10:34 AM
i totally agree with you, so why do JBL favor a cluster grouping?

pmakres1
07-21-2005, 10:43 AM
i totally agree with you, so why do JBL favor a cluster grouping?

I'm not sure, I've pondered this one myself. Your observation of the near field coherency may be one reason, another could simply be cabinet space / cabinet size considerations. I'm sure some other forum members will have some thoughts on this.

As for the 4315's, I've never had the pleasure of auditioning a pair, but I have never doubted that they would be a great system, and I'd love to own a pair. I have a pair of 4313B's on one of my smaller systems, and I really like them. Come to think of it, the 4313B's also have the drivers in vertical alignment!

Peter

DavidF
07-21-2005, 11:54 AM
you rarely read on this forum anything about 4315's...my favorite JBL. i have only had very limited exposure to them and they seem to have had a short production run...not very popular, yet many sound engineers swear they are the best. would love to trade my tannoy system12DMT's plus lots of $$$ for this speaker of similar value (4315) any opinions on this model?
the other thing that i have always pondered is JBL's reluctance to physically line up their drivers in a vertical line array. i would not try to second guess the designers at JBL--they have forgotten more than i will ever learn. but, this is totally sacrilegious to any live sound engineer. the only vertical array i can think of in the JBL lineup are the original L100's. you can totally hear a difference in phase coherency and imaging when compared to the other series of 4310/11/centuries. the only theory i can come up with is they are favoring a cluster design which works well in a near field position. still, it is my belief that a speaker 'floats' better when drivers are vertically aligned.

I think the 4315 had a fairly long production run. The reference chart shows production ended in 1983, so that was 9 or 10 years? Donít know about quantity sold, you could be right about that. Although marketed as a compact format monitor, they really were closer to the large format rather than the small format. So then, why not opt for the large format monitor.

The advantage to vertically aligning the drivers (not necessarily in absolutely the same vertical axis) is that interference issues among the drivers tends to be minimized over the horizontal plane. This is fairly standard for home speaker designs, including JBL with some exceptions, where a wide, stable horizontal response is preferred. The vertical response is "sacrificed" since much of the inter-driver interference problems occur moving up and down due to the vertical alignment. I think you are correct on a clustered design for commercial consideration. Near field monitoring forces compromise where the total package needs to be small, the drivers need to be closely clustered to focus the response within a few feet, or arrayed so the box does not block the view. But if you know that the user is locked into a certain position, the speaker array can vary so long as the response at the known sweet spot is focused and flat.

I would add that the 4315 really is vertically arrayed, similar to the 4333, 4343 etc. Yes, the ultra high is off to one side of the high, but I think the answer to this is that the ultra high comes in so high in frequency that there are no directional cues from this location on the baffle. You would want to respect mirrored location on the baffle with the ultra high driver though.

I am always interested in a peer comparison with the larger format models as well since I have always had an unfounded lack of enthusiasm for mixing a horn driver with a direct driver crossed over right smack in the mid range typical of the large format monitors. Since others do have such enthusiasm, I need to know what I am missing.

DavidF

Lancer
07-21-2005, 12:58 PM
Nice David!

My personal pair of 4315B's were mirror imaged.

I am always interested in a peer comparison with the larger format models as well since I have always had an unfounded lack of enthusiasm for mixing a horn driver with a direct driver crossed over right smack in the mid range typical of the large format monitors. Since others do have such enthusiasm, I need to know what I am missing.

With respect to the 8-inch in the 4315, the 10-inch in the 4343, and the 12-inch in the 4350, I considered them to be the hearts of those systems. I think they are all worth a listen. Any JBL enthusiast should have the experience of listening to them. Being able to compare them directly with Consumer models such as the L250, 250Ti and XPL200 was quite nice.

Mr. Widget
07-21-2005, 02:09 PM
With respect to the 8-inch in the 4315, the 10-inch in the 4343, and the 12-inch in the 4350, I considered them to be the hearts of those systems.

I would second that.

I am amazed at the incredibly visceral power of the 2202 in the 4350, but today I would be inclined to go with one of the smaller drivers in an ultimate system. I prefer the more detailed quality of these drivers.

Widget

DavidF
07-21-2005, 02:16 PM
...With respect to the 8-inch in the 4315, the 10-inch in the 4343, and the 12-inch in the 4350, I considered them to be the hearts of those systems...

Yes, I have read in these parts of their excellent build quality and response characteristics. So much so that I found a pair of 2108H a little while ago and have recently begun to work them into system. This would include the 2105 5" but not the 2405 (too pricey, like a lower xover point, seems OTT unless complimenting other horn drivers). I understand that the 10" and 12" mids are able to carry a heavier loan in their intended roles, but I wonder if the lighter mass of the 8" would match up, in dynamic terms, with a horn upper-mid driver. Perhaps, perhaps not. There is still a significant mass differential. The 2108 seems like a good match for fitting to a custom horn, though. But hey, that starts me down a whole new expensive path, of course.

David F

Lancer
07-21-2005, 02:29 PM
The 112H/2108H goes very well with the LE5H/2105H and the 044 or 066.

I've never been inclined to try it with a horn. Never crossed my mind.

I'm using my 112H/2108H with the 093Ti and 046Ti.

DavidF
07-21-2005, 03:47 PM
I'm using my 112H/2108H with the 093Ti and 046Ti.

Ah, so. Similar to my concerns about matching a horn upper mid to a quick lower mid cone driver. I would expect that the 2108/112 would also transition well to the low mass 093Ti. Similar issues are seen in matching electrostatic and film-type drivers to cone woofers to keep the dynamic range up at the cost of some blur in the transition. Excellent idea.

David F

Valentin
07-21-2005, 04:19 PM
i think in cluster formation there are also less diffraction efects so the mid and hi frecuncy are more smoth

Robh3606
07-21-2005, 04:57 PM
This is a neat thread

Hello Akira

"still, it is my belief that a speaker 'floats' better when drivers are vertically aligned."

Mine too. When I built my 4344 clones I was not sure if I should stack them so I chickened out and did them stock. The rest of the drivers are in a straight line with the 2405/077 next too the 2307. They seem to image very well that way. I would hazard to guess it may improve but to be honest I have no plans to cut a new set of holes in the baffle. The other systems I have are all in line and image better but like anything else between diferences in horns and driver spacing ect. there are lots of things going on to really say that's why.

Hello David

"But if you know that the user is locked into a certain position, the speaker array can vary so long as the response at the known sweet spot is focused and flat."

That's an interesting observation. The 4344 are very focused compared to say XPL-200 or a monitor using the 2344 horn. Controlled patern and they image diferently from either the XPL or 2344. In my room the XPL and 2344 are the image kings but the 4344 is very good in it's sweet spot.


"With respect to the 8-inch in the 4315, the 10-inch in the 4343, and the 12-inch in the 4350, I considered them to be the hearts of those systems."

Hey Lancer I would have to agree those drivers bring alot to the table. The 10" are my favorites and the little 115H-1 in the XPL's is surprisingly good and does a great job between the 12 and the TI drivers.

Rob:)

Titanium Dome
07-21-2005, 10:17 PM
Vertical alignment? How about the PT800 stacked on the PS 1400 in the Performance Series? Along with the IsoPower baffle, what a combo!

Yeah, I've got the original L100 Century with the vertical alignment and prefer it to the later models, even with a bit less oomph at the bottom.

Another oft-overlooked vertical beauty is the L5 with the 708G, 706G, 704G and 039TIA all in a nice line.

Of course, the oft-derided but much loved (by me) SVA Series was vertical alignment in spades. The symmetrical vertical array survives in the HT Series. Also, the HLS Series kept its drivers all in a row.

In fact, in the consumer arena, virtually all of JBL's current top models (Performance, TiK, K2) are vertically arrayed. However, some of the Synthesis Systems seem to have drivers all over the baffle. :dont-know

Lancer
07-22-2005, 06:48 AM
Yeah, everybody knows by now to go vertical for home use. The number of home systems "gone vertical" is staggering.

If you have 4315's and want to mirror image them you only have one box to build. ;) Also, every JBL system I've ever owned in 30 years has ended up mirror imaged if it didn't already come that way. Think about the dual holes in the larger monitors and the lack thereof in the 4315 - price points!

I'd personally do them vertical ala L250 or PT800/PS1400 and use a better matched HF like an 044 or 066. Then again, one can leave them exactly as is and enjoy them for what they are.