Woofers for a 3,5-way system

[Ian Mackenzie]

But using 2234 for example this would be the same "problem", wouldn´t it?


I have no experience with the 2216 at all. But in case of a single 15" I would still use my TAD 1603´s...

No.

Look at the 4600 response using a LE14H-4
The system is 91 dB rated sensitivity

So you shove two in a box. What happens?
Due to the shape of the native low end bass response you need to CUT -3 DB with complicated EQ to get a usable bass response.

Otherwise you will get a big hump
You end up with a shit bag sensitivity of 91 dB after adding a low pass filter at 150 hertz

In comparison the 2234 rated 96 dB sensitivity requires no EQ due to the shape of the bass response and you retain the 96db sensitivity.

Both drivers are working to deliver a response around -3 dB @ 30 hertz
Full power down to 26 hertz
http://www.jblpro.com/pub/obsolete/443035.pdf
Subjectively you may as well using one LE14 because one of the drivers needs to continue up to crossover to the horn

Edit
In summary there are two controlling variables that make using the two LE14 sub optimal (dang it)

1. The 91db sensitivity using two LE14 in this approach. That is 5 dB below the 2234 and the 1400 woofers . In terms of realestate and cost l don’t think it’s a smart plan.

2. The bass hump that requires shaving off- normally this would add like mutually coupled drivers close together but you have to live with the stock 91 dB sensitivity of the single LE14 going to the crossover point of the horn. So you are wasting the use of the second LE14.

If you have the Tads l would just try them as they will outperform the twin LE14 in the scenario you are proposing in the bass




Btw l recall they reduced the amount of aquaplas on the LE14-4 to improve the mid band performance

[pos]

The LE14H-4 is rated for 92.5dB/1w/1m : http://www.audioheritage.org/vbullet...?21501-Le14h-4
When simulated in a 73L box it behaves almost exactly like a 2234H in a 140L box : http://www.audioheritage.org/vbullet...l=1#post215472

So all in all installing a pair of LE14H-4 in a 145L box with a 26Hz tuning and a 2.5way crossover similar to the 4435 should give the same response as a 4435, minus 3.5dB

[Ian Mackenzie]

Well not all LE14s are created equally are they

I would like to see them measured in a pit.

The rest of that thread needs careful reading

You would need to be able to build LE14-4s
http://www.audioheritage.org/vbullet...l=1#post215647

What you see on paper is not always subjectively what you enjoy.

My reference to 91 dB in the 4600 not the raw driver.

It’s entirely up to the user

But for my money l would bet on building a project box for the Tads first.

If you cross them over at 650 hz with a passive network and end up a simple but highly musical system running just a First Watt F7

[Dr.db]

I have read that thread and I must have missed the part when somebody dehorted from the LE14h-4 in a 2.5-way system!?

If a LE14h-4 has 91db in reality that is very low sensitivity indeed.


I´m using the TAD 1603´s right now... A very good allrounder. I was just wondering if I could do better with two 14"-woofers...
Expect for the huge enclosure, the 1603 isn´t a suitable woofer for a 3,5-way setup as the 2234, or is it?

[Ian Mackenzie]

The LE14-4 spec sheet has 92.5 dB but those conditions are probably different to the 4600 spec sheet l posted earlier. It had a passive crossover in series with the woofer

That is the point l was making.

The LE14 -4 was great in the 4600 in its own right with that box tuning
You might be perfectly happy with that but your expectations might be otherwise.

With the added cost and complexity you need to work out what the benefit is in an of an un tested configuration with 2x LE14s ? It might go a bit lower but it’s much larger and at best 92.5db sensitivity.

If you plan to bi amp and have plenty of power that might not be a problem but it’s going to be more of a studio head basher than a simple system with higher sensitivity that can exploit the musicality of high quality amps ect.

Loud with lots of power and enjoyment with high sensitivity and quality amps are two different aims.

[Dr.db]

Allright, I think the LE14´s are just too low in sensitivity for such a system.

Thanks a lot for your help.

[Earl K]

JBL le14a woofers are truly wonderful project woofers ( even if only to make a Zilch inspired EconoWave ).



It's really a crying shame that this thread has managed to find a way to talk you out of owning 1 ( or 2 ) pairs.

The eBay supply of these used woofs is not endless.

[Ian Mackenzie]

Hi Earl,

Dr DB could have bought LE14a drivers as you say without any discussion here.

But he had a very specific application and wanted to stay with that.

It was then revealed the LE14H-4 might be an option.

My feedback
“The LE14 -4 was great in the 4600 in its own right with that box tuning
You might be perfectly happy with that but your expectations might be otherwise.”

If you can advise on availability of recone kits or LE14H-4 drivers that would be great?

[Ian Mackenzie]

Allright, I think the LE14´s are just too low in sensitivity for such a system.

Thanks a lot for your help.

Check out the baffle image in this link :

http://www.geocities.jp/arai401204/H...FL/A290FL.html

It’s two woofers paired to operate up to the crossover point.
That as a system is well storied

You could try that with dual LE14s.
If you actually follow that approach the overall sensitivity reference to 2.83v (4 ohms) higher around 95-96 db.

You could then try the Jbl 4435 design approach and compare using dual LE14s.

If l can say this you have a propensity to seek outcomes to specific ideas then take the plunge.
There is more value for you in putting your toe in the water with a driver as most of us do and learning with practical experience. No two diy loudspeaker ideas are the same and trying a driver out will give you a solid basis for evolving your project until you reach your goal. (That is in fact how many loudspeakers make it to market.)

[Earl K]

Hi Earl,

Dr DB could have bought LE14a drivers as you say without any discussion here.

But he had a very specific application and wanted to stay with that.

It was then revealed the LE14H-4 might be an option.

My feedback
“The LE14 -4 was great in the 4600 in its own right with that box tuning
You might be perfectly happy with that but your expectations might be otherwise.”

If you can advise on availability of recone kits or LE14H-4 drivers that would be great?

Ian,

While my words may seem like I was pointing fingers / I really wasn't.

It's more like, I was young once and I know how it goes with talking ones-self into all sorts of situations due to self-directing the conversation ( ie; what one thinks they want to pursue, isn't always the best way forward ).



PS; I have no knowledge on the current status of JBL kits.

[turnitdown]

Beautiful work there EarlK. I, too, have built (sort of) Econowaves with LE14As. Listening to them right now with 2342s and 2426s mounted to them. Delicious. A second set of cabinets is being cut now (twin 3.9 cu ft) to exactly match but without horns so I can run dual LE14s with an 18mH on the second a la 4435. I'll measure when they're all assembled but, in theory, they will work.

Until the cabinets are built I have LE14H-1s in there but will switch out to the LE14As. I have eight of those but only two LE14H-1s.

I love that old driver (all re-foamed b.t.w.)

[Earl K]

Beautiful work there EarlK. I, too, have built (sort of) Econowaves with LE14As. Listening to them right now with 2342s and 2426s mounted to them. Delicious. A second set of cabinets is being cut now (twin 3.9 cu ft) to exactly match but without horns so I can run dual LE14s with an 18mH on the second a la 4435. I'll measure when they're all assembled but, in theory, they will work.

Until the cabinets are built I have LE14H-1s in there but will switch out to the LE14As. I have eight of those but only two LE14H-1s.

I love that old driver (all re-foamed b.t.w.)

Ahhh, not my work actually ( though I wish I could take the credit for the handiwork of Zonker92 ).

The pic comes from Katalyst's thread over at AK.

[Ian Mackenzie]

Hi Earl

If someone picked up the ball and started re issue versions of drivers and packaged them with like the Loudspeaker Enclosure Handbook it would take the guess work out of a lot of these threads.

Before the www you either did the above or took Pot luck and crafted your own design.
I recall 5 iterations before l went for the 4345s.

Perhaps with the internet the Y Gen prefer second guess the solution with their iPhone on the way to work.

[Dr.db]

Check out the baffle image in this link :

http://www.geocities.jp/arai401204/H...FL/A290FL.html

It’s two woofers paired to operate up to the crossover point.
That as a system is well storied .

Running two woofers up to the horn should be worse for the midrange, shouldn´t it?
It´s the way TAD builded there big monitors, so there must be an advantage.

If l can say this you have a propensity to seek outcomes to specific ideas then take the plunge.
There is more value for you in putting your toe in the water with a driver as most of us do and learning with practical experience. No two diy loudspeaker ideas are the same and trying a driver out will give you a solid basis for evolving your project until you reach your goal. (That is in fact how many loudspeakers make it to market.)

LE14´s are pretty rare in germany and importing from the U.S. is expensive, so I like to discuss before putting big amounts of money in a new project.

[JoeNelis]

I've listened to double 1400nd's extensively, but never double 2235's, so I cannot compare. Joe Nelis has them now and also has 4355's, so he may chime in here. I would characterize them as accurate and articulate really very good woofers and may eventually feel I need some E2's to be as happy or better, though I am holding off on that for now. I can say that in my small E2 experience I thought that midrange to be better.

By four-way I mean put a midrange between the woofers and treble horn, 300 to 1200. In that layout the midrange is taken out of the woofers, so the question of low bass/midrange balance when doubling up linear woofers is mooted.

I would add that in general I think when using legacy woofers--that is anything prior chronologically or technically to the hyper-engineered uni-frame 1400nd, 150xAl, 2216, and also 1501fe, and TAD 1102 and 1601c--for the lowbass into midrange the benefits of bandwidth limiting our still in effect. That is, the liabilities of the added complexity of three and four-way systems are more nearly worthwhile. Even with those woofers doubling up and digital eq are employed to reach the lows the 2231/2235/2245 get to, not that there's anything wrong with that.

(I've never heard the LE14-4, so I can't speak to that.)

Hi joe here, I bought the 1400nd of speakerdave for my project. Having owned 4350 and 4435 the dual 1400nd is the best bass I’ve heard to my ears period. As Dave said there accurate and also go deep. Everyone who has listened to them simply loves them, just wish I could get some more of these drivers just amazing.


Joe.