Le85

[yggdrasil]

I have a pair of LE85 in my DIY's. The other day I had to open them up and found phenolic diaphragms.

Shall the LE85 have phenolic diaphragms?

What is the pro version of LE85?

[Mr. Widget]

Those are probably 2470 diaphragms. The LE85 should have an aluminum diaphragm with a smooth surround which is the same as the pro 2420. The current replacement diaphragms are from the 2421B which has an aluminum diaphragm and diamond pattern surround.(This is considered an upgrade and is quite costly.) You can also use a titanium diaphragm with diamond surround. I personally don't like the titanium diaphragms but others prefer them and they are the most cost effective replacement.

Widget

[John]

Widget is right about the Diaphram. The 2461 + 2470 used the same one. Since your system is a four way you might like the phenolic diaphram better,before you invest in aluminum dia. I would see if you can borrow a pair of drivers with the aluminum dia. for a taste test. I am running a pair of phenolic's in a three way. 2215-2461-2405 and the sound is all there,nothing missing and surpasses my Altec 19's in tightness and warmth. By the way in the next few weeks I am going to do a taste test my self with a pair of 2420's with 2421 dia. in them. This will simply be a test done with my ears and a brew,will report my findings.

[Mr. Widget]

The brew will most certainly be the most critical part of your "taste test". :D


Widget

[Mr. Widget]

Actually all kidding aside, I haven't done this comparison myself and will look forward to your thoughts. While listening focus on detail resolution. While the tonality (frequency response) may be equally good or better? with the phenolic, due to it's greater mass I would expect the resolving power to be less. I base this on my comparisons between aluminum and beryllium. The lighter material while having a similar frequency response is able to reproduce nuance that the more massive diaphragm can not.

Widget

[John]

Yes I will do my best,one day soon I think I will take it to the next level and get some test equipment. Oh and some would agree the brew can be considered testing equipment

[yggdrasil]

Thanks a lot.


One of the reasons why I started wondering about this is that I am working on a smaller project with Altec 806-8 on Altec 811 horns. They have more details.

Also I get the feeling that the vocalist is unwilling to come out on the floor to sing to me, at least compared to the Altec's.

BTW are there a place on the internet where one can order original replacement diaphragms?

[JBLGUY]

I have found that the linen dia.'s sound nicer than some of the aluminum or titanium. But then I don't drive them that high. I use a ribbon driver for above 5k and a 375 driver from 800-5 k. But down lower the linen outshines the others IMHO


Last weekend we tested a 2485 against 2441 against 2445 and the 2485 sounded the best with the 2441 second and the 2445 definatly last.

[Mr. Widget]

What frequency range were you comparing the phenolic, aluminum and titanium drivers over?

I have found that comparing the aluminum 2441 against the TAD 4001 beryllium both operating on the same horn from 800Hz up the tonality was very similar but the "inner detail" (to use one of those Stereophile type terms) was significantly improved with the beryllium. I certainly agree with your opinion of the titanium driver. I think the titanium drivers seem harsh and bright. My guess is that this is due to their higher distortion content.

Widget

[yggdrasil]

I found aluminum diaphragms on speakerrepair.com at $244 a piece. They are not considered at this time. Found some aftermarket diaphragms at $35 which I consider just to hear the difference.

The LE85's play 1200Hz to 7000Hz.

I use a lot of time thinking about what can be approved in this and my other projects. Other factors I am wondering about are: Can there be a phasing problem causing this? Would another horn construction change this(tractrix / smith)?

[Steve Gonzales]

I do have LE85's with phenolic and some with original aluminum and some 2420's with original aluminum in my set-up and I've found that if you cross the phenolic's over at 5k, they sound just fine. They do have a wonderful sound with the human voice. What Mr Widget says about them is true to a certain extent. In a WIDE range A-B test, there is a marked difference in detail but as I said, it is dependent on how high you ask them to play. So there is truth in JBLGUY's opinion too. Oh, I've got to add the requisite IMHO. Their problem is with the MASS due to the limits of trying to get that much weight to move more than say 5000 times per second. You would be suprised to know how much and how soon "break-up" occurs with different materials. If you can use them within and not over that point, you're good to go. There is also the "taste" factor. What sounds great to one person doesn't always even sound good to another.

[JBLGUY]

Hi Mr Widget

We were primarily comparing the lower range of Freqs. Like from 300hz to the 2000hz range. We were testing all of the drivers in some Large wood horns that my buddy sells. I left him with my 2485J linen unit after our afternoon of comparing and he then tested it further and reported days later that he liked the sound of these so much better at the lower freqs. The 2485j has to have other units take over for it up higher. We didn't really concentrate of the stuff above 2000hz , but the 2485J would be a very bad full range unit as it only really goes to 6k and not very well at that. It is stricky IMHO only good for the lower mids......but for that it is great
When I was there the 2485J sounded much better than the 2445. I didn't really like it much at all. Of course the 2485 is JBL's speech range unit. But if crossed over under a 1000hz it sounds very nice. Very subtle and unobtrusive.
In my system I use it from 300-800hz then feed into 375 model till 5k. Then my Stage Accompany Ribbon drivers do the rest.

They are not shown in my Avatar. I will post a thread on them later.

Widget your dry humor is great and I love the subtl quips and jabs...very clever you are at times

Have a great day or night.

Hey Steve, how are you enjoying the big slant plates 2395's

I love mine

Thanks

[Steve Gonzales]

I LOVE EM'. I think we are on the same page with the phenolic's. I was disappointed to see them in my first pair of LE85's until I LISTENED to them with a H92 crossed over at 5k. WONDERFUL with the female singing voice especially.

[Mr. Widget]

I don't have any first hand experience with the 2482-2485 running through a large horn from 300Hz to 1KHz, but I can imagine that it would be very nice indeed. It brings up two issues in my mind. The first is purely aesthetic, forget WAF, I really don't want to be intruded upon by that much speaker even in a dedicated listening room... my opinion is subject to change and I can just see myself setting up some 400lb monsters at some point in the future. :)

The second issue is one I have been musing over for quite some time. It gets back to, "What is our fundamental goal in audio reproduction.?"

Certainly if I want to hear the most faithful production of Michael Tilson Thomas conducting the San Francisco Symphony, I should walk the 6 or 7 blocks from my house to Davies Symphony Hall and listen to the real deal. Obviously this becomes more problematic if I want to listen to Jim Morrison fronting the Doors. But the real question to me becomes, "Are we trying to create a hologram of the band in our listening room, recreate what the mixing engineer heard at the console, recreate what the artist's intention was, or what?"

Depending on the recording, there are quite a few "Audiophile" systems out there that do a pretty good job of creating the acoustic hologram. Very few also have the dynamics of a well thought out horn system, but there are some out there that do both. On the other end of the spectrum are the primarily DIY rigs that have many horns scattered about the front of the room each covering a narrow band of frequencies. These systems typically have amazing dynamics and if done well can have a very natural timbral balance. They typically have a large diffuse sound that in many ways more closely resembles going to hear live music. (In my experience I have never been to a performance where with closed eyes you could see the singer in the center of the stage etc.)

So the question is, "Do we want to recreate the sonic hologram that was engineered into the recording or are we after a sound that is more like hearing live music performed in a venue?" We will never get the London Philharmonic Orchestra into our listening rooms so short of only listening to soloists what do we choose?

Personally, while I do regard the holographic representation of music as primarily a "special effect" it is very cool and it can be quite startling. (I know people who prefer to listen only with headphones as they like the band to be in their heads... that is a bit to psychedelic for my taste.) I am willing to sacrifice this holographic effect a bit for the dynamics but I am not yet willing to give it up entirely.

Widget

[Mr. Widget]

How the hell did we get here from a pair of mis-diaphragmed LE85s? :applaud:


Widget

[johnaec]

One other thing that should be considered is dynamic balance. It would sound rather odd to have outstanding HF dynamics and a somewhat compressed, limited LF. If you have enough LF units to match the output of a horn HF, you might be OK, but I imagine problems might arise when your HF is 10 times more efficient than the LF, with substantially better dynamics to boot... The again, since much dynamic content comes from higher harmonics, it may be OK? :hmm:

John

[JBLGUY]

Depending on the recording, there are quite a few "Audiophile" systems out there that do a pretty good job of creating the acoustic hologram. Very few also have the dynamics of a well thought out horn system, but there are some out there that do both. On the other end of the spectrum are the primarily DIY rigs that have many horns scattered about the front of the room each covering a narrow band of frequencies. These systems typically have amazing dynamics and if done well can have a very natural timbral balance. They typically have a large diffuse sound that in many ways more closely resembles going to hear live music. (In my experience I have never been to a performance where with closed eyes you could see the singer in the center of the stage etc.)

So the question is, "Do we want to recreate the sonic hologram that was engineered into the recording or are we after a sound that is more like hearing live music performed in a venue?" We will never get the London Philharmonic Orchestra into our listening rooms so short of only listening to soloists what do we choose?



Very well said Mr W :applaud:


For me dynamic range is the ticket. I feel the live perf. is the way to go. If it sounds closer to live, I like that.

I don't mean at those kind of volume levels though. That would be too loud for me to be comfortable. I enjoy a level just above conversation level but also below shouting level. Kind of where you feel some bass a little.

Any way when people first hear my setup I think they are taken back a bit by the dynamics and quickness. Now there are smaller setup's and speakers that have better quickness, but they can't seem to do it at a louder volume. This is where a big horn setup will blow everything else out of the water. You can dial it up too where things staret to get impressive now.

I beleive that if many differant sizes and style of speakers where A-B behind curtains at the same type of volumes, most people would choose a big horn setup. IMHO

[JBLGUY]

One other thing that should be considered is dynamic balance. It would sound rather odd to have outstanding HF dynamics and a somewhat compressed, limited LF. If you have enough LF units to match the output of a horn HF, you might be OK, but I imagine problems might arise when your HF is 10 times more efficient than the LF, with substantially better dynamics to boot... The again, since much dynamic content comes from higher harmonics, it may be OK? :hmm:

John


Yes for sure John.

Driver matching is most important. This is why I prefer multi amping and electronic crossovers. You really get to fine tune the driver to each other then.

I know some people who fiddle around with passive xovers trying get everything to sound matched. it pretty hard to compare that trial and error method with a full electronic unit. yes you need more amps but what a differance this all makes to the DIY horn setup. Now it will realy smoke....hopefully :blink:

[Robh3606]

"So the question is, "Do we want to recreate the sonic hologram that was engineered into the recording or are we after a sound that is more like hearing live music performed in a venue?" We will never get the London Philharmonic Orchestra into our listening rooms so short of only listening to soloists what do we choose?"


Good question!! I like a balance of great dynamics great tonality and good imaging. I want to be able to hear what's really on that recording and not be limited with either frequency response or dynamics. I like that effortless quality where you can do the dynamic swings with no strain. The imaging which I will still try for is secondary to the others. As far as getting an orchestra in my living room the closest I have ever came is using an HT rig with either SACD or DVD's with DTS. On a good recording the sense of space you can get is really impresive.

Rob:)

[scorpio]

Hi, I'd be real interested to learn about your experience of using the aftermarket diaphragm, I am using LE85 from 600 Hz up in a 2 ways system, they have rather old Ti diaphragm with the diamond surrounds and sounds OK. I have wondered what nice new Al membranes would do, but the cost... Specially here, it's 240 euros, that's close to 320USD... All I can afford here is aftermarket, that's why I have not made the change yet. Maybe I'll try to get something in the US on my next travel there.


Cheers

[majick47]

Re diaphrams for the LE85 on the advice of Mr. Widget and Zilch I had new 2421B diaphrams installed replacing aftermarket diaphrams in my first pair of L200b. The cost was considerable but the results were excellent, much smoother and detailed especially at higher volume. I just picked up a second set of L200b speakers and the LE85 have the original JBL 30 year old diaphrams. I'll a/b the two pairs of LE85 to see if I can hear a difference between the old and new JBL diaphrams. If they sound good I'll stick with the original diaphrams until the budget allows for upgrading to 2421b. First I need to recone the 136a woofers and might install 2405 tweeters/3106 crossovers to match the first pair.

[yggdrasil]

Just over a week ago I finished a small project with Altec 806 and JBL 2402. Of course I had the time to listen to them for a few days before they were picked up.


Now that I have switched back to the JBL's with phenolics, new experience added. There are a lot of details missing in the upper midrange. :banghead:

Do any of you have experience about what frequency the amount of details is getting to low with the phenolics? Maybe I should redesign the crossover to 3-4000Hz and switch the 077's with a pair of 2402?

Should I just bite my teeth together and get me some 2421B diaphragms?

Maybe I should just sell the LE 85's and get me a pair of 2441's instead? That can be possible for $500.

So many questions!

Any thoughts are welcome.

[Zilch]

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=47092&item=7305920210&rd=1

See "Marketplace."

[yggdrasil]

Thanks Zilch. I'll follow them. :)

[Steve Gonzales]

Johnny, I wouldn't trade the 077's. The 7k that you're asking the phenolics to reach is too much. The stock aluminum is BETTER for your set-up. I ask much less of my phenolics and they do fine. Yes, it is the MASS problem, too bad too. You will LOVE the stock or 2421's when you hear them. The 2402, however good, is my least favorite of the UHF's JBL made and it is extemely hard to beat an 077. Unfortunately, stock JBL diaphragms are mucho $$$, but they are worth EVERY RED CENT!!. Good luck on the eBay listing!

[aust-ted]

Hi

You guys are putting up some pretty good posts at the moment. Finding I am spending more time here. JBLs must be addictive.

While I do not have any experience with 2" phenolics, I do own a pair of 2482s coupled to 2380As. My listening experience with them compared to 2450s was in line with Mr Widget's comments on the 2470. Pretty good but lacking a little detail by comparison. Mids crossed over at 800Hz, 2404s at 5KHz using a M553.

However I have read that the 2482s are good down to 300Hz. Got me thinking that if I could construct the right horn I might be onto something. But to address the top end, I was thinking of using a 2402 from say 2KHz and a 2405 say from 7KHz. What do you think? Or would you be better to use a 2420 in place of the 2402? And what horn? A 2344 perhaps?

Regards
Ted

[Mr. Widget]

A 300Hz horn will be a giant, but it may be just the trick for your 2482s. I would come in at 1200Hz with a 2420 or better yet a 2441 and use the 2405 at 10KHz.

Widget

[aust-ted]

Mr Widget wrote "A 300Hz horn will be a giant, but it may be just the trick for your 2482s. I would come in at 1200Hz with a 2420 or better yet a 2441 and use the 2405 at 10KHz."

Yeah Thats the drawback. Would need to use as small as possible horn for the 2420 (or 2441) to physically fit the whole thing in the room. Have not seriously worked it out but might also have to compromise too much on the 300Hz horn to make it fit.

Regards
Ted

[yggdrasil]

A 300Hz horn will be a giant, but it may be just the trick for your 2482s. I would come in at 1200Hz with a 2420 or better yet a 2441 and use the 2405 at 10KHz.

Widget

Why would you want to cross in the 2405 as high as 10KHz?

I havent tried it, have never had the drivers and crossovers to test it in house at the same time.

[Mr. Widget]

I feel that it sounds better... I was basically following JBL's lead. In the early applications JBL used a second order filter at 6.5KHz in the L65 Jubal... I always thought it a bit harsh. For their off the shelf network and in the earlier studio monitors they stayed with the second order network but moved up to 8KHz. In the early 80's JBL's crossover networks started to become significantly more advanced across the board and in the final monitors that used the 2405 they used a third order crossover and pushed it to 10KHz.

I have used both the 3106 (second order 8KHz) and the network from a 4355 and there is a significant improvement.

Widget

[yggdrasil]

Today I have 8ohms. At least I think I do, because it says so on the back of the LE85.

The crossovers are calculated with 8 ohms. There is also the fact that there is an L-pad attenuator between the crossovers and drivers.

Meaning:
12db band-pass crossover, 1200Hz and 7000Hz -> L-pad attenuator 8ohms -> LE85 8ohms.

The dia's on e-bay are 16ohms.

What will happen?

[Mr. Widget]

If you have an original JBL aluminum diaphragm with a smooth surround it is a nominal 12-16 ohm driver regardless of what the nameplate says. If it is an aluminum diaphragm with diamond pattern or JBL titanium diaphragm with diamond pattern it can be either 8 ohm or 16 ohm. If it is an aftermarket diaphragm you have ?


If you are using JBL networks that were designed for the LE85 they are designed for the 12-16ohm impedance. If you are using custom made networks that were designed for a nominal 8 ohm load and you put a proper LE85 (2420) diaphragm in it you will want to adjust the network.

Widget

[Alex Lancaster]

:) Widget, You must be thinking of a 375/2440 when You say "smooth surround"; All the L85/2420´s I have seen had the tangential lines on the surround.

[Mr. Widget]

Damn! You are right... it has been a long time... actually no, I helped Infredible replace his 2420s a few months ago, OK my brain is getting soft.

Yes I had a mental image of the 4" diaphragms as I wrote that. The 1.75" diaphragms have a radial pattern of angled tangential lines for the original aluminum version and then in the 80's when they discovered the diamond surround they changed it and the impedance.



Widget

[yggdrasil]

Yesterday evening I opened the speakers, took out the cables from the LE85's. They ohmed out at 10,6Ohms..:banghead:

That explains a lot..... E.g. odd response when adjusting the attenuators.

As a quick and crude attempt to fix the fact that both the attenuator and band-pass filter are designed for 8Ohms I added a 16Ohms resistor in parallell with the driver.

What does this do with sound quality? Is it a way to go around the problem of finding 16Ohm attenuators?

[Mr. Widget]

http://www.partsexpress.com/

have 100 watt 16 ohm L-pads at very reasonable prices. You may not need 100 watt pads, but they tend to be better built all around. I would suggest you order a pair. Shipping will no doubt be more than the parts, but they are small and the entire order should be relatively painless.

Widget

[yggdrasil]

Thanks Widget.


I'll order more than just the pair. There will be other projects later on. Think I will move the upper crossover frequency too if I can get some Aluminum diaphragms.