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KCjblSound
06-28-2022, 03:43 PM
So this is what I have:

L200B or L200A cabinets (I have both)
2216nd woofer
LE85/H91 mid
077 hf

and L200A/NX16A crossover

Looking for some help me design crossover or suggest a crossover that would work well with this?

The first issue IÂ’m having is finding the right woofer crossover design for the 2216nd. Ideally I would like to copy the 4367 but I cannot find the crossover specs. Then again they show the crossover point of 700 hz and IÂ’m thinking 1100 hz or 1200 hz would be more ideal for this 3 way?

Or should I just use the NX16A for the low and mid crossover? My biggest issue with the NX16A crossover being the size capacitor used on the mid (6uf). It is half the size of the cap used in the L200 original (12uf), L200B/L300 (16.5uf), Nelson Pass L300 (22uf).

For the HF 077 I was just going to do the single 1uf cap same as the Nelson Pass crossover.

Any recommendations are appreciated. IÂ’m kind of new at this.

Ian Mackenzie
06-28-2022, 10:40 PM
Sounds like a nice project and a nice woofer.

If your looking for a better than okay result your going to needs a passive network specific to your drivers.

I can assist with a passive crossover and have all your drivers.

If you click on my email address in my signature you can send me an outline of what you’re looking for and l will correspond with you and look at some options with Leap 5 simulations.

Ian

nedseg
06-29-2022, 07:23 AM
I have similar (see posts on AudioKarma as well)
L200
2216ND-1
N8000 xover driving
LE85 & 077
I'm biamping (tossed the LX16s) via a Venu360, LF@1khz, and (2216) EQ's posted elsewhere here.
I measured the ports (it's a 5 cu ft cabinet) thinking they'd need changing, but concluded not.)

The ND1s sound fantastic - No complaints whatsoever.
The horn is definitely a limitation - still considering alternatives.

I'm defintely interested in what Ian comes up with too!!
(Scott is my 'advisor')

Mr. Widget
06-29-2022, 08:58 AM
In my list of possible future projects, an upgraded L200 is on the short list.

I'll either use a pair of 1501AL woofers that I already have or get a pair of 2216NDs.
The plan would be to modify the cabinets to accept the longer 2312 horns and use an active crossover in the 800Hz region. Between the LE85 and the 077s I would use a passive crossover.

Interested to see what you guys come up with.


Widget

Earl K
07-03-2022, 03:02 PM
The first issue IÂ’m having is finding the right woofer crossover design for the 2216nd. Ideally I would like to copy the 4367 but I cannot find the crossover specs. Then again they show the crossover point of 700 hz and IÂ’m thinking 1100 hz or 1200 hz would be more ideal for this 3 way?
For the HF 077 I was just going to do the single 1uf cap same as the Nelson Pass crossover.

Any recommendations are appreciated. IÂ’m kind of new at this.

Actually, it's the S4700 and the way it implements of the 2216nd that you ought to be copying for your lowpass ( IMO ).

After a bunch of research I would suggest that RobH3606s lowpass for his 2216nd is what you ought to try out ( his lowpass is pretty close to the guesstimated values used in the S4700 with a couple of functional differences > due to his box not having the convex//curved kick-plate installed which appears to bump-up a range of frequencies ).

Here's the range of frequencies that the kick-plate seems to bumpup ( this ground-plane measurement of the M2 parts from a German HiFi magazine is something LHF member "pos" posted many years back ).

90800

Along with some raw responses taken from JBL's EDS sheets.

90802

Rob implemented a 3-pole design that uses a 4mH coil ( amp side ) followed by a 52uF capacitor ( that goes to ground ) with a 2mH coil connecting directly to the woofers + input connector ( whatever color that actually is ).
- His stated values somewhat electrically start to mimic the EQing effects of the kick-plate ( here, the "bump-filter" center can be clearly seen in the included impedance graph in the simulation ) .

For the horn circuit I would first try the Nelson Pass designed circuit ( even though it was auditioned for the the HL92 long horn, my simulations show it'll work quite well for the shorter HL91 ).
- If you desire, you can reduce the primary 22uF cap ( C3 ) to around 18uF ( gaining a bit extra//mostly un-needed protection unless you're cranking it > without losing the magic the circuit was designed around > which is "low-Q" filtering ).

If you play your stereo loud then the Nelson Pass circuit is most likely not for you ( since it takes the horn down to 700hz and will definitely stress that nice aluminum diaphragm ).

My sims suggest the user should connect both the woofer and horn circuit using the same positive polarity ( whatever colors on the drivers that translates to ).
- This difference from the Nelson Pass recommendation results from the horn ( and therefore Acoustic Center ) being shorter by 3 inches.

Blue = 2216nd , Red = 2231H ( both are taken from JBL EDS sheets )

90798

90799

The L200 enclosure with the 4" deep protruding sides has a bunch of unavoidable cavitation//deflection effects that could use a bit of extra EQ boost from the woofers lowpass ( somewhat like Rob executed ).

The coil values listed here for the S4700 network are obviously wrong ( perhaps they're even a deliberate mis-direction for a current product ).

90801

:)

Ian Mackenzie
07-03-2022, 05:57 PM
Hi Earl,

Thanks for contributing some ideas.

I’m a little delayed with rain for outside measurements of the horn, the slot radiator and the 2216 driver in an enclosure that closely resembles the L200 dimensions. I also have a renovation.

From a diy perspective the user can implement a very simple crossover such as a first order and experiment.

However, with the limitations of this type of driver combination previously outlined in a paper by David Smith, D B Keele , JR and John Eargle some more thought, measurements and assessment of the crossover is worthwhile with powerful CAD loudspeaker software. Back then crossover designs were iterative using empirical techniques and theory. So with real measurement data and advanced software the door is open to further exploration.

There are also the physical problems such as the 150-160mm offset of the drive voice coils. Just how audible these physical differences are is another matter. The Altec 604E had similar offset with the woofer and concentric horn driver and innovative solutions were found by Floyd and Toole in the early 80’s. Of course if you want to you can apply corrections in dsp and come up with something too. But sometimes the method creates other problems and complexity.

I don’t think there is any hurry. As l pointed out to Patrick Bateman over on Diyaudio.com. Supposition makes for interesting discussions. But a belief held without proof or certain knowledge; an assumption or hypothesis is dangerous ground to be walking on in loudspeaker crossover network design.

Ian

Mr. Widget
07-03-2022, 08:12 PM
So with real measurement data and advanced software the door is open to further exploration.
Absolutely, but every speaker is a different beast.

A few years back I wanted to see if I could make my Project Widget loudspeakers work with a single amp instead of being tri-amped with a passive super tweeter. I took a series of precise measurements with CLIO and worked with Rob using LEAP to model a 4-way passive network for my Project Widget loudspeakers. The networks that Rob and LEAP suggested were fairly complex, but I built them on a test bed with very high quality caps and coils and began exploring. I could never get the speakers to sound as good as they do in their tri-amped configuration.

FWIW: I also ran them fully quad-amped at one point, but found that to my ears and to the ears of others who listened to them at length there was no audible benefit with the quad amp configuration.


Widget

Earl K
07-04-2022, 05:45 AM
Hi Earl,
<<<SNIP>>>

So with real measurement data and advanced software the door is open to further exploration.

Ian

Ian,

That inferred assumption that I'm not working from real measurement data and advanced software is pretty off-base.

I am using good software and respectable//repeatable files

Granted I'm working with borrowed files ( traces ), but they are mostly all CLIO generated. ;)

My work builds upon the very solid foundation of others ( Rob Hamel + Zilch + Giskard ).

Here's one such file used;

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=20912&stc=1&d=1164610728

How else is one going to obtain such a large representative sampling of this classic driver ( le85 ) ?

The horn driver file that I'm using is serial number 22222 ( as chosen by Zilch ) .

Since I have only a single 2420 diaphragm in a 2470 body ( + that diaphragm needs refitting ), I choose to use Zilchs traces for their greater accuracy and consistency.

Do you have 6 le85's to choose from ?

FWIW, I measured the AC offset ( Z offset ) at around 5.8" with REW > using a 2425/2307 as a standin for the 2420 ( the top-plates//VC are at the same depth ) and a 2225H for the woofer.
- Measurement was on-axis to the horn throat + the "Center 2 Center" of the 2 drivers was 14" .
- The biggest "iffyness" here is "how divergent is the Acoustic Center of the aluminum coiled 2216nd ( with it's dual coils ) is when compared to the single copper-coil of 22xx series of drivers?"

Here's a look at the acoustic summing that Zilch achieved with his "Keeper" 3-way using his 4507 cabinet ( somewhat like your stated intention of using a substitute cabinet ).

90811

That " Keeper" network is this one ( the polarity of the horn driver needs to be flipped compared to the woofer );

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=20002&stc=1&d=1162181499


Using Zilch generated, plus JBL EDS files, along with the approximated values of S4700 woofer network, I'm able to produce these results ( applying the 5.8" Z-offset figure and changing some of the LC values in the Keeper network );
- it seems that Zilch used around 9" for an acoustic offset which I believe explains the need to flip the polarity of the horn-driver.

90812

Here's the Nelson Pass bandpass married to RobH's lowpass values;

90813

As earlier mentioned ( to the OP ), I would first build-up the Nelson Pass variant for a listen (if loud playback levels aren't needed > one can see the low 700hz crossover point which will stress that diaphragm if played loud ).
- The Zilch 3-pole variant offers the higher 900hz point ( but his LC values don't agree with my sims > unless I increase the "Z" offset. Therefore, one would need to experiment some by substituting LC values to see which values work best at crossover.

:)

KCjblSound
07-04-2022, 09:38 AM
Confirmation
To be clear you are definitely wanting to add the 077/2405 slot radiator and make it a 3 way?
What power amp or amplifier are you using?
Do you know which diaphragms you have in your LE85Â’s?

If l upset the natives and wildlife with the tests you maybe requested to make a donation. Lol

I have attached images of the drivers to relieve any anxieties Earl may have about whether any of this is real.

Thank you for your generous time and efforts with this.

I have the 077, I figured if I have them then why not? As my understanding is the LE-85 doesnÂ’t do much above 12k hz.

This will be ran on a 30 WPC Fisher 400 tube receiver with the audio source being a modern DAC.

The diaphragm in the LE-85 are new Radian 16 ohm diaphragms.

The reason I was wanting to crossover at 1,200 hz is because my understanding is the H91 is distorted below that level and from what IÂ’ve read the 2216nd is capable from 30 hz - 1,200 hz.

I have both L200 and L200B cabs, I figured I could play with which port type (1 vs 2) sounds better. Although the L200B are in much better cosmetic condition.

Mr. Widget
07-05-2022, 07:50 AM
Don’t be offended but you what we call pig headed. Through and Through
Start using it (your brain) instead of blowing off your big ugly New Yorker mouth. There’s nothing worse. Your a really Bad Ambassador for anyone watching this forum from anywhere in the World.

They are watching you.

You reactions are very offensive and defensive person. Your frightened or something? Your passing the blame.

You don’t have the bandwidth to investigate, understand and moderate. Your not prepared or capable of accepting change.

Your ineffective and obsolete: Deleted. Ian, don't be offended, but look in the mirror. You are not being a very good ambassador yourself.


Personalities aside, you have obviously put a fair amount of thought and effort into the technical side of your posts, but so has Earl and so have others. This is meant to be a collaborative space, it works best when people work together building on each other's thoughts and experiences. It's great that you want to help others with their designs and their DIY projects, but try to be more like Nelson Pass, he is able to offer wise council without being condescending.


Widget

1audiohack
07-05-2022, 09:03 AM
I am interested in this thread as well.

I have a pair of 4333’s that have had all three horns in them and I am just not happy with them. I have done a fair amount of DSP work with them and of course just for fun ran the stock crossovers too.

I need to get them out and really work on them as it’s kind of been a just for fun here a little there a little project.

The 2311’s in the 4350’s seem less objectionable and I think it is the crossover points allowed with a 12” between the 15’s and 2441/2311/2308. I am either going to swap the 2235’s for 2234’s or most likely 2216’s.

I haven’t had a single day to myself single mid April. Grrrr. Maybe this weekend haha.

All the best guys.
Barry.

Mr. Widget
07-05-2022, 10:43 AM
Hey Barry,

Regarding your comment about trying all three horns, specifically which horns are you talking about?

On a larger topic, in my experience virtually every horn sounds better when you raise the crossover frequency. This would align with your comments on the 2311. In an earlier time, JBL used that horn with a 500Hz crossover (Then it was called the HL93 with the lens). Bumping it up 1100Hz would certainly help! Similarly the 2307 horn in the 4343 is pushed up to 1250Hz which can only help.

Unfortunately in both cases we are talking 4-ways... trying to keep things simple in the L200 vein does present a challenge.


Widget

Ian Mackenzie
07-05-2022, 06:40 PM
Edit: Material Deleted Due to Lack of Interest
Mr Widget: I don't accept your Feedback
This is an explanation what you lot are doing wrong and you keep doing it over and over.
I'm here for that enquiry made by the OP and that enquiry only. I'm not here for your entertainment.
You've missed the point unfortunately. Earl missed the point and went all over the place and started regurgitating other peoples
designs, ideas ect. He did not ask further questions to actually determine other important relevant information.
The OP made it clear why and what he wanted. Then Rob unfortunately over reacts and it over.

Example
If you ring up a bank about something specific to your accounts and you have questions its it appropriate to listen
and understand why they are calling? Ask further questions so you can fully and correctly answer and the enquiry quickly and
efficiently. What you don't want to hear is someone blathering on about what they think and what someone else did.
You don't want to on the phone for hours or making several calls and no resolution.

This is my world. I build systems, I design customer journeys, I train people. I'm an expert in that area and made a career out of it.
Coming here is no different frankly. It never was and it never will be.

If you feel my approach is condescending your in the wrong business. You might be and that up to you.
I don't have to fit in with your mentality and how you see the world.

I don't suffer fools gladly.

I receive scores of "specific direct enquires" from all over the world and its growing all the time.
Condescending in not the feedback or in the testimonials I receive.
Your attempts to label and make defamatory comments towards me are pointless and don't answer the issue.

1audiohack
07-05-2022, 10:21 PM
Hello Mr. Widget;

2307’s, 2311’s and 2312’s have been in my 4333’s as well as a pair of 2307’s that I parted off in a lathe at the 1.5” bore point and re-flanged them to accept 2451’s. I needed the 2311’s for another project.

Barry.

1audiohack
07-08-2022, 03:03 PM
So this is what I have: …Looking for some help me design crossover or suggest a crossover that would work well with this? ….

Any recommendations are appreciated. IÂ’m kind of new at this.

Ian it seems you may have missed the last sentence of the original post. ?

Barry.

Robh3606
07-08-2022, 07:38 PM
Ian it seems you may have missed the last sentence of the original post. ?

Barry.

Hello Barry

I think you hit the nail on the head.

That is an open invitation from the OP for any and all suggestions. That means any member of the forum who has a suggestion is welcome to post. I will admit to a novice it can be really difficult to determine which road to go down but that is the nature of the beast on any of these internet forums.

Rob :)

hjames
07-31-2022, 02:50 PM
Hmmm - I have strongly considered setting up another L200 system -
I was quite pleased with the sound using the 2234 woofer, the 2405 slot on top, and the 2445J mid driver on the walnut smith horn.
I thought the wood horn had a much better, smoother sound than the JBL exponential horn.
After the work setting up the Heathkit Valencia - it sounds quite nice - but, my memory of the L200s seems better.
I checked back with @tinpan, but he didn't know I was still interested.
So while I was trying to sell the Heaths, he got an offer and sold off the L200s ... sigh

hjames
10-01-2022, 07:20 AM
So the new L200 project is ongoing.
I got a pair of 2445j pro drivers, have a pair of the 2328 horn adapters, have a source for some replacement wood horns, and found some "Nelson Pass style" L300 crossovers.
My old system had the 2234 woofers in place, but I'm interested in the 2216nd drivers this time around.
Looks like the hard part may be finding a pair of the 2216nd woofers ...
most places I've looked show them as sold out/out of stock.

Robh3606
10-01-2022, 07:38 AM
Hello Heather

The place in Florida had a sale on them and has not had them in stock since. Did you get on the waiting list??

Rob :)

hjames
10-06-2022, 07:52 AM
Hello Heather

The place in Florida had a sale on them and has not had them in stock since. Did you get on the waiting list??

Rob :)

I emailed Melissa to put me on the waiting list Sunday about 1PM. (2216nd - not the -1)
Just before 5 she replied, said they were back in stock.
I immediately ordered a pair - just over $900 for the pair, shipped. (ouch!)
Yesterday I got an email that they were being shipped from San Diego and I'll have them next week!
I'll share more once I see them.

Contact info in image to minimize harvesters

hjames
10-10-2022, 10:50 AM
I'm hoping to get a pair of L200 cabinets in the next month or so from the Subwoof closeout sale.
I have a set of JohnW Walnut horns on the way from Texas (originally commissioned by Dhar)!
I have a pair of JBL 2445j 2" tweeters on the shelf, and the 2328 adapters to fit them to the walnut horns.
I've got the coated JBL diaphrams on the way to warm them up for home use ...
I'm almost ready for a winter project, once those pesky Heathkit/Valencias go away ...
91181
91182

And UPS just came by ... 2 boxes delivered ...
unbroken, unbent packages-
so I took a peek!
91180






In my list of possible future projects, an upgraded L200 is on the short list.

I'll either use a pair of 1501AL woofers that I already have or get a pair of 2216NDs.
The plan would be to modify the cabinets to accept the longer 2312 horns and use an active crossover in the 800Hz region. Between the LE85 and the 077s I would use a passive crossover.

Interested to see what you guys come up with.

Widget

Mr. Widget
10-10-2022, 11:50 AM
And UPS just came by ... 2 boxes delivered ...
unbroken, unbent packages-
so I took a peek!Great News!!!


Widget

hjames
10-14-2022, 02:17 PM
Even better news - a big box just arrived - a VERY well packed pair of JohnW walnut horns.
Local audio-friend Dhar commisioned them at some point after I had my original pair,
he sold them to a Lansing member in TX, and, he just sold them to me for my current project!

91195


Great News!!!

Widget

macaroonie
10-22-2022, 01:58 PM
Just a thought Heather , why don't you rent a DSP from one of the many ? pro sound houses in the DC area. That would give you the opportunity to assess the mode of operation , connectivity and ultimately SQ.
I would run it up as a two way in the first instance.

M

hjames
10-22-2022, 05:49 PM
Always a possibility ...
I'll look into that, once I am much further along.
So far I have the new diaphragms in the 2445j drivers,
and mounted on the JohnW walnut Smith horns.

The 2216nd drivers are awaiting a cabinet.

Current discussions include possibility of cabinets from Subwoof,
or contracting cabinet builds from some of the local gurus.
Baseline design is a 2 way - woofer internal, horn on top.
Easy enough to work with that.

But I really want to get the Altecs outta here first.
And selling the Von Schweikert VR4s would help as well.
(I need the room).



Just a thought Heather , why don't you rent a DSP from one of the many ? pro sound houses in the DC area.
That would give you the opportunity to assess the mode of operation , connectivity and ultimately SQ.
I would run it up as a two way in the first instance.

M

Ian Mackenzie
10-23-2022, 04:34 PM
Beautiful.

alskinner
11-18-2022, 12:37 PM
Installed a pair of 2216nds in my L300s. I am using a Nelson Pass crossover wired in original polarity. Although the crossover and cabinet of the L300s are probably not optimal they do sound very good. There is better definition of bass notes and the woofer meets the horn better to my ears. I have about 30 hours play time on them so the sound my change slightly.

Mr. Widget
11-18-2022, 03:13 PM
Installed a pair of 2216nds in my L300s. I am using a Nelson Pass crossover wired in original polarity. Although the crossover and cabinet of the L300s are probably not optimal they do sound very good. There is better definition of bass notes and the woofer meets the horn better to my ears. I have about 30 hours play time on them so the sound my change slightly.Excellent!

What woofers were you using previously?


Widget

alskinner
11-18-2022, 03:21 PM
The 136a that were reconed with one of the last of the 136a kits. I have also used 2235s at one time.

Mr. Widget
11-18-2022, 03:42 PM
The 136a that were reconed with one of the last of the 136a kits. I have also used 2235s at one time.I’d love your opinions of the various woofers.


Widget

alskinner
11-18-2022, 05:01 PM
I’d love your opinions of the various woofers.


Widget
The 136a and the 2235 are very similar in sound. The 2235 does a very good job in my 4344 clones crossed at 290hz. however both these woofers seemed to struggle to meet the 800hz cutoff to reach the LE85 and HL92 Horn in the L300. Building the Nelson Pass Crossover improved this a lot but I could still detect it could be improved upon. Not that the speaker was bad at all and I was fairly satisfied.

Thanks to Heather I found the 2216nd was back in stock and ordered them intending at some point to build a M2 clone. I decided to try them in the L300. I was very pleased to find the new woofer was almost seamless with the horn. The bass is also more articulate in that low bass notes can be heard without any muddiness. Also being very light to handle doesn't hurt. The sound may change somewhat when the woofers break in. I am sure it could be even better in a cabinet redesign and crossover designed for it, but for now I am well pleased.

I wish had the test equipment some of you have to verify my suppositions. But for now I rely on people like you and the others on this forum.

Mr. Widget
11-18-2022, 07:32 PM
The 136a and the 2235 are very similar in sound. The 2235 does a very good job in my 4344 clones crossed at 290hz. however both these woofers seemed to struggle to meet the 800hz cutoff to reach the LE85 and HL92 Horn in the L300. Building the Nelson Pass Crossover improved this a lot but I could still detect it could be improved upon. Not that the speaker was bad at all and I was fairly satisfied.

Thanks to Heather I found the 2216nd was back in stock and ordered them intending at some point to build a M2 clone. I decided to try them in the L300. I was very pleased to find the new woofer was almost seamless with the horn. The bass is also more articulate in that low bass notes can be heard without any muddiness. Also being very light to handle doesn't hurt. The sound may change somewhat when the woofers break in. I am sure it could be even better in a cabinet redesign and crossover designed for it, but for now I am well pleased.

I wish had the test equipment some of you have to verify my suppositions. But for now I rely on people like you and the others on this forum.Thanks for the mini review... it aligns with my experience and expectations of the new driver in that enclosure.

My guess is that the best results would be from adding a DSP on the woofer. Actively crossover to the horn and bump up the very bottom a bit.

But at the end of the day, if you are pleased, it is a winner!


Widget

alskinner
11-18-2022, 08:06 PM
Thanks Widget

You are correct on the bottom end. I had already bumped up from 30hz to 60hz about 4 decibels it does need it this cabinet. I will keep the DSP option in mind.


Regards
AL

maxwedge
11-22-2022, 07:42 PM
I would switch the polarity at the ND2216 so it is in phase in the crossover region with your compression driver. The 2235 and 136a are both negative polarity drivers and the ND2216 is positive.

Ian Mackenzie
11-22-2022, 08:49 PM
I don’t know. It’s like all these things of it measures the same it will sound the same. Just like amplifiers. Blah blah 😕

maxwedge
11-23-2022, 06:48 AM
I would switch the polarity at the ND2216 so it is in phase in the crossover region with your compression driver. The 2235 and 136a are both negative polarity drivers and the ND2216 is positive.
I don’t know. It’s like all these things of it measures the same it will sound the same. Just like amplifiers. Blah blah 😕 I agree but OP says he doesn't measure and the ear is very adaptable to sound, whether in phase or not, and can lead someone to think it sounds good when in fact it's not quite right. It was just a suggestion to try but if he likes it as is then that's fine.

Mr. Widget
11-23-2022, 09:32 AM
I agree but OP says he doesn't measure and the ear is very adaptable to sound, whether in phase or not, and can lead someone to think it sounds good when in fact it's not quite right. It was just a suggestion to try but if he likes it as is then that's fine.+1

Certainly should be tried.


Widget

Earl K
11-23-2022, 12:43 PM
Making basic response measurements is pretty easy these days.

There are some pretty Hi-Rez Smartphone apps ( some are free and are mostly 1/3 to 1/6 octave RTA's ) that allow one to see ( at the very least ) how things mesh together at crossover ( and additionally, what LF + HF extension is like ).

Most of Apple's more recent smart phones have a pretty linear built-in mic // making those iPhones the better choice for ad-hoc, on the cheap measurements.

Here are some internet comparisons for older iPhones;

:)

alskinner
11-23-2022, 03:48 PM
Maxwedge
I didn't realize that the 2216nd was positive cone forward. I will definitely swap polarity and see what effect it has. It may be an improvement or maybe not. Nelson Pass reversed polarity on the mid range driver on his L300 crossover and found he liked the sound better.

Earl
Thanks for the information on the Iphone apps available. I have an Iphone 11 and will see what's available. As soon as Thanksgiving is over I will try to measure the speaker with the woofer wired in both polarities and report back.

Thanks to all and have a great Thanksgiving
Al

Ian Mackenzie
11-24-2022, 04:16 AM
Haaa,

Please don’t make me think.

Let’s see.
According to a sketched diy plan of the 2397 the horn on Google the horn protrudes 6.87 inches behind zee baffle.
Then the 2428 adapter 4 inches
And the depth of the driver to the diaphragm. perhaps 3 inches
That about 14 inches behind the baffle

The 2216 is about 4 inch deep. 14 - 4 = 11 inches

That’s about a difference of 11 inches difference in the physical acoustic centres
In metric that’s 280mm difference.

A 800 hz crossover point has a wavelength of 430 mm
So therefore this offset will have a lagging phase shift at the crossover point of 234 degree @ the 800 hertz crossover. As 180 degrees is the same as opposite electrical phase it could potentially help to wire both drivers in phase. Try it and see.

The rest is small movement of the horn of around 2 inches to obtain a good in phase situation which will make or break it subjectively.

This will depend of the amount of phase shift in the horn at the crossover point. I recall the 2397 extends down to three or four hundred hertz.

I don’t recall that Nelson came up with. I would borrow an Ashly 24 db active crossover with the adjustment to start with that as it’s a simple thing to set up and see what happens. Then make a passive crossover if desired using the active best case scenario (measured)

You are poking around in the dark with a passive crossover from scratch without measurements. It never is quite how it should be unless run in a sim with solid data.

Those horns have a nice open midrange. I’d put the slot in the baffle on the inner listening side under the horn so the air in the top end above 7000 hz is focused between the loudspeakers. The 2397 of diffraction limited as l recall by the 50 mm horizontal slot in the horn.

Have fun.

alskinner
11-24-2022, 08:13 AM
Ian

As always I respect your input and guidance. Right now I am not working on the 4344s I am working on the L300s with the 2216s in them with the LE85s and HL92s. So I am not sure what effect the length of the horn and the depth of the 2216 will be on the needed polarity.

A little history on my L300s. I bought them for $1100 dollars many years ago. They were not pristine but in good shape cosmetically. I had the woofers reconed and assumed the LE85 and 077 were in good shape (bad assumption). Upon building the Pass L300 crossover the speaker sounded better but not just right. I took the back cap off the LE85 only to discover someone had put phenolic diaphragms in them. I had a spare set of 85s and it made a lot of difference in them for the better. I started enjoying them again. This taught me not to assume anything about anything used and sometimes new. When I ordered the 2216s I didn't intend to use them in them in the L300s but wanted to test them to insure there were no defects. But the more I played them the better I liked them.

You all are absolutely correct in that I will need to get some measurement equipment as I have spent countless hours trying to make the 4344s work with the Westlake style horn and 2241 driver and never got them to sound just right so I went back to the 2307, LE85 and 2405 and am fairly satisfied with them. I really like the sound of the 2441 and Westlake horn but without accurate measurements and a crossover redesign I'm dead in the water. Early on I did use an Ashly 4001 and while the results were good I really wanted a passive crossover with just one amp.

I did find an Iphone app for rudimentary measurements, I am looking for a calibrated mic and some good measurement software. If anyone knows of a good reasonably priced setup please let me know.

Regards
Al

Ian Mackenzie
11-24-2022, 02:49 PM
Hi Al,

Thank you for outlining your journey. I had similar impressions with the 2397 stop my 4345 clones.

Bring up the condition of compression drivers is a good point when trying different components. It pays to know what’s going on.

My earlier post was to give some insights on what can happen with a reasonably long horn. The horn in the L300 with the LE85 has a depth in the same ballpark as the 2397.

I do have an iPhone Dayton mic but l have never used it.

The thing with the L300 is we don’t have the flexibility of being able to move the horn back and forth to modify the response in the crossover region. I would try out the 2216nd and simply listen with the polarity either way. With any luck one way with offer an obvious “that’s it” impression. There are more scientific approaches to obtaining a descent crossover transition in such situations like the L300 with a passive crossover and the long horn but it’s a deep topic to explain and would require a whole thread.

Over on my forthcoming website (under construction) l will be publishing some project systems such as the L300 with advanced passive crossover design techniques aimed at further improvements with stock components and alternative drivers.

alskinner
11-28-2022, 07:04 AM
I did indeed had the 2216s wired out of phase. Testing the woofers with my trusty 1.5v battery the cone does move outward with positive voltage to the red terminal. The sound is now more centered with more coherent bass rather than coming from each speaker separately. I have run test wires from the crossover to the speakers out the port hole so that I can change polarity rapidly without taking the speakers in and out.

I did get AudioTools from Studio Six Digital measurement software for the Iphone. Although I can get readings using the internal Iphone mic, I doubt the mic is very accurate. I have ordered a miniDSP UMIK-1 mic which should give more accurate readings. I will also be able to use REW and TrueRTA software to compare results. I know there will be a learning curve before I can get real accurate readings but it's a start.

Regards
Al

Mr. Widget
11-28-2022, 08:52 AM
I use Studio Six Digital with the built in mic and for many tasks it is pretty close my more accurate methods of measuring.

My guess is that at least some of the added coherence from the rewired woofers is due to confirmation bias, but it is probably the “right” way to integrate them into your design.

I am confident that the 2216Nd woofers are an upgrade and may go that way if I ever get around to my own “L200” project. I only bring up confirmation bias because it affects us all and needs to be taken into account as we stumble towards excellence.


Widget

alskinner
11-28-2022, 01:23 PM
Mr. Widget

Understand what you mean by confirmation bias. That's why I left the test leads so I could change the polarity back and forth. So that when I can measure what I think I'm hearing and apply some equalization I may prefer them out of phase. I have a small room to play them in and there are other factors that can influence the final sound heard. The last thing I want to do is to have others follow my subjective impressions without something to back them up with.

The L300 by today's technology is pretty ancient, but damn they're fun to listen to. My goal is to make them sound the best they can be with what I have to work with.

I do have one question. What source is used to test speakers with. I mean would one use white noise or is there a standard source? Forgive me if this is covered elsewhere on the forum.

Regards
Al

Mr. Widget
11-28-2022, 01:51 PM
The L300 by today's technology is pretty ancient, but damn they're fun to listen to. My goal is to make them sound the best they can be with what I have to work with.
Understood and Agreed!



I do have one question. What source is used to test speakers with. I mean would one use white noise or is there a standard source? Forgive me if this is covered elsewhere on the forum.

Use pink noise. I burned a CD with pink noise on it and often use that, or you can use the headphone jack on your phone and plug that into the system.

I also use sine sweep tones and others that are specific to different applications, but for general use pink noise is the one to use.


Widget

Ian Mackenzie
11-28-2022, 05:22 PM
https://studiosixdigital.com/audiotools-modules-2/

There are some useful tools here. Like all things diy the proviso is the user has an understanding of what the tools are, how to use the tools, when to use them and what the results mean?

If your patient with a learning curve REW in its latest version is by far the most accurate and economical bit of test kit a diy audio person can have.

alskinner
11-28-2022, 06:24 PM
Thanks Ian,

I do have the Audio Tools and am endeavoring to start the learning process. As soon as my microphone arrives I will try REW also. I may go into seclusion for a while until I'm comfortable with the processes. If it's OK I may from time to time PM some of you all to look at some of my results and the way I came about them to see if I'm on the right track. Not that I want to be secretive I just don't want to confuse anyone until I am comfortable with what I'm doing.
Thanks to all for the help and guidance.
AL