rank the 43XX series for me in order of best most accurate sound

[Ian Mackenzie]

Story Four - A Summary

The next story is the genesis. This involved settling on one three different mid high frequency arrays way back in the late 1990’s - early 2000’s.

audax mid cone+ 2420+ bi radial 2344
audax mid cone+ 2420+2397 horn+077 slot (with a converter- not ideal but it did worked)
audax mid cone +2420+2307/2308+077 slot

*The 2420 was fitted with a new JBL titanium diaphragm and tested.

I used both L+ R loudspeakers with a jig for each array. After weeks of comparisons l was vexed about which was the best? They were divergent in some respects. Not even a glass of red wine helped. Dang it.

Edit: The listening room in my rental was counter intuitive for the 2397 and the bi radial horn which lite the large flat walls up to much. Big 1st reflections made the sound stage seem bigger than it should have been. Hindsight can be a wonderful thing….Lol.

So l left it for a bit and went to some of my preferred shows. Jazz clubs, live venues and a few concerts. I quickly determined what l enjoyed the most. The catalyst for this was the seats l chose. Near the front. I also picked up recordings of these artists at the venues.

I like to feel immersed in the presentation. I need to hear and feel the impact of sounds.

Simply put l want to listen to my music that way. Sound that makes make you stop and look. I like the experience to get bigger as it gets louder. It sounds a bit old school like a Klipschorn demo doesn’t it…Lol. Very how’s the father in law?

I think developing your own criteria of what’s important to you early on is really important. My list of likes above allowed me to critically listen and determine which alternative translated the most of what l needed to enjoy my music. The specs don’t tell you how it will translate in your situation. The translation is what matters.

The room and how the system is set up can influence the accuracy of the translation. So can the signal path.

This also relevant buying a SH system, a new system or selecting what clone to build. The big advantage of building a system is you get to make your own hopefully informed choices.

In the end the audax mid cone +2420+2307/2308+077 slot was the preferred alternative. That combo delivered what was important to me in my circumstances. I found the 2397 wouldn’t integrate properly. The bi radial was too diffuse in my room.

This was the genesis for building a clone of the 4345. Technical information from Greg Timber’s was the 5th element which made it work correctly.

You could say l went full circle. I like circles.

[Ian Mackenzie]

Back on topic

When you buy a loudspeaker it’s built to a price or it could be out of your budget. It’s been designed to a criteria that may not necessarily meet all your preferences. It’s also voiced to meet certain market preferences that may not appeal to you.

Some systems are too detailed while others are light on in the bass. How do you fix that when you buy a loudspeaker? It ain’t easy. This is the challenge when you buy on face value without listening before the purchase decision.

The legacy 43XX were live sounding but does that means it’s not for you? No not necessarily.

Do you need a highly refined sound that can be clinical on less than perfect recordings? It can be a double edge sword on your music library.

In the 43XX range there is something for most people (excluding hifi buffs).

On high resolution drivers l prefer high resolving power components in the signal path with a tad less resolving power components in the loudspeaker.( excuse the pun)

A mediocre signal path (pro amps and 1970’s- 80’s HiFi classics) paired with high resolving components in the loudspeaker can be irritating. Its like not having a breather on the sewage from the Lav. When the last of it goes down it unfortunately gets sucked back up leaving an unpleasant odour.

But then again what you don’t know won’t hurt you will it. Forgive my Aussie humour….Lol.

[Ian Mackenzie]

I want to hear a pair of 4348s and am betting they would be right there at the top of the line. None of the prior ~10" would be competitive with the differential drive, neodymium 2251s used in these monitors and the 1500FE is no slouch.

https://www.facebook.com/watch/?v=477067592304607

I heard the 4348’s in Japan. I don’t know why but it didn’t seem to come together subjectively. I much preferred the 4338. The horn in that system is really nice.

Zilch had a set of those 4348 horns which l heard at his home way back in 2007 with the LHS CA gang. I vaguely recall it was a centre channel with 10 inch woofers. My recollection was it was good. Zilch was a really nice guy. His threads documenting his measurements were classics. It would drive Dale nuts who’s narrative was in strict lock step with the JBL way. I dearly miss Lancer and Miss Orchid. Rob had a crush on her…Lol

It was an interesting adventure from down under. I hired a van and on the way over the bay bridge my compact camera fell off the bench seat and slide under the foot brake…..Lol

[Ian Mackenzie]

To make the 43XX system comparisons more revealing I have attached a comparison of 4343 horn response and the 4344 horn with its upgraded compression driver. These response overlays are of the drivers only without the associated networks.

For clarity I have only shown the on axis and the horizontal 10 and 15 degrees off axis response.

The divisions are 5 db in 1 db increments so this is under the microscope.
Measurement with Leap LMS and Leap calibrated mic.
Smoothing applied for clarity.

Looking at the two overlays the 2426 compression driver is smoother overall. Of more interest is that the smoothest response is 15 degrees off axis. This coincides with the JBL recommendation of up to 15 degree toe in when setting up. Ref 4344mk2 owners manual. The problem area is around 3khertz and a small off axis response corrects this. The response extends out over 10 khertz on axis but falls in the off axis measurements. Not shown here but the 9.5 Khertz crossover point appears well chosen.

The LE85 response is less smooth and exhibits a more pronounced depression at 2.5khertz. It does extent out well above 10 khertz with a bump at 12 khertz. Not shown here the 8.5 hertz crossover point appears well chosen.

The networks serve to EQ these drivers to some extent and provide a bandpass filter to restrict the response.

I haven't shown any other drivers or diaphragms because the effect of a dusted diaphragm isn't obvious in an FR response measurement. I have seen that the ribbed JBL diaphragms have significantly more break up modes than the plane domes.

If anyone found this interesting let me know.

[1audiohack]

….If anyone found this interesting let me know.

I certainly do.

Thank you Ian.
Barry.

[jpw retired]

Hi JPW;

Since Ian went in deep and it wasn’t frowned on by you, I will too.

When I was a kid we had a JBL shop in our town that had most of the 43XX series on the floor, not all at once but I did get to hear 4343’s, 4345’s and 4350’s and being young I wanted them all. I could not tell you at this point which I might have thought were the most accurate. They were dynamic as hell!

Later I acquired, in order, a pair of 4350’s, 4365’s, new, and 4333A’s. I also built a pair of kinda 4345’s. I made them 10 cubic feet based on something G Timbers said about the 2245.

For accuracy, like Widget said, the 4365’s win, but you are talking about vintage 43XX’s.

I found no real love for the 4333’s, no matter what I did. I revisit these from time to time and always just put them back in the barn.

The 4345 clones never had passive crossover components but I could never fill an energy gap, between the 2245 and 2123. That may show something missing in my integration chops. I revisit these from time to time and always just put them back away. No matter how well I can get them to measure, I am never happy with them.

My 3450’s are exactly what Widget describes as cheating. The first fix was replacing the 2202 with TAD 1201M graphite cone drivers. Screwed around with the compression drivers, everything from the original 2440’s through 2450’s with TruExtent beryllium and landed on NOS 2441’s as the winner with the 2405’s.

Then 1500AL woofers from the Everest family. Four way amplified with DSP. I love them. I still take them out and out back in the open and tweak on the DSP and they just get a little better each time.

I also have a pair of DD66000’s that have 67000 woofers and crossovers in them, also in the barn.

Ironically what wins in my living room is the 4365’s with ARRAY1500 subs. Go figure.

I also have the DIY itch and my loose plan is for some spare AL1500 woofs, 2251 mid woofers, 4338 horns with 2450Sl’s and 2405’s. Hopefully they will supply my dynamics itch.

Barry.

What a great collection you have. It must be super fun to tinker with all of the alternatives at your disposal. John

[jpw retired]

To make the 43XX system comparisons more revealing I have attached a comparison of 4343 horn response and the 4344 horn with its upgraded compression driver. These response overlays are of the drivers only without the associated networks.

For clarity I have only shown the on axis and the horizontal 10 and 15 degrees off axis response.

The divisions are 5 db in 1 db increments so this is under the microscope.
Measurement with Leap LMS and Leap calibrated mic.
Smoothing applied for clarity.

Looking at the two overlays the 2426 compression driver is smoother overall. Of more interest is that the smoothest response is 15 degrees off axis. This coincides with the JBL recommendation of up to 15 degree toe in when setting up. Ref 4344mk2 owners manual. The problem area is around 3khertz and a small off axis response corrects this. The response extends out over 10 khertz on axis but falls in the off axis measurements. Not shown here but the 9.5 Khertz crossover point appears well chosen.

The LE85 response is less smooth and exhibits a more pronounced depression at 2.5khertz. It does extent out well above 10 khertz with a bump at 12 khertz. Not shown here the 8.5 hertz crossover point appears well chosen.

The networks serve to EQ these drivers to some extent and provide a bandpass filter to restrict the response.

I haven't shown any other drivers or diaphragms because the effect of a dusted diaphragm isn't obvious in an FR response measurement. I have seen that the ribbed JBL diaphragms have significantly more break up modes than the plane domes.

If anyone found this interesting let me know.

I sure do. At least I can understand frequency response curves!

[Ian Mackenzie]

In reality when you pick up a woofer how it works is actually quite simple. A coil of wire immersed in a magnetic field with an alternating current creates a force which drives the movement of a larger diaphragm in and out.

But getting it to play nice is a bit more complicated. The diaphragm, the suspension and the coil in the magnetic gap all have to be carefully engineered. Undamped resonances in the suspension and the diaphragm causes problems with sound quality. Harmonic distortion is primarily caused by variations in the inductance of the as it moves in and out of the magnetic field. Non linear distortion is caused by non symmetrical suspension and asymmetry in the magnetic field.

What most people don’t realise is that the coil of wire inside the driver absorbs nearly all the power created which can be expressed as voltage x current = watts. Nearly all direct radiators are only two percent or lower in efficiency. As a result the coil can increase in temperature to over 400 degrees in only 20 seconds.

What happens? The resistance of the coil increases very quickly and less force in created by the coil. Various techniques and coil designs including split voice coils spread the heat out along the length of the voice coil former.

[Ian Mackenzie]

Edit- l’ve added this article by Don.

It provides some valuable context on the relevance of accuracy and at what stage in the recording process accurate monitoring is required (mastering). Once you have read the article then apply that logic by association to your regular musical entertainment at home. Critically accurate monitoring at home is not how the recording engineer want you to enjoy it.

This logic supports my comments earlier that a highly transparent and resolving signal chain (including power amplifiers) should take precedence over highly accurate monitoring (and the associated high resolution drivers).

A step back from that edge delivers more consistent listening enjoyment on an emotional level while still kicking your personal big ticket must have’s that l discussed earlier. These are your own individual likes.

I know l sound like l’m harping but many people suffer the disassociation ( or confusion) of sound quality and emotional enjoyment with absolute accuracy. They are different things. It can be the road to hell when in fact it’s all about listening to the music, not the equipment.


Studio Monitor Evolution and Use - Don McRichie
https://www.audioheritage.org/vbulle...lution-and-Use


INSIDE THE STUDIO MONITOR
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Requirements for
Studio Monitoring

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THE ACOUSTICAL LENS
By GEORGE L. AUGSPURGER
Operation and performance of various types
of devices used professionally and in home
hi-fi speaker systems to disperse and shape
sound energy from horn-type driver units.

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The above links are excellent reading for a more formal and objective understanding of JBL’s philosophy behind the legacy 43XX systems. There are many facets to the design considerations behind each system. The author also calls out a few home truths that are equally applicable to the use of these systems in domestic situations which covers most of us here today. Notable of these call outs are are the application of uniformly distributed sound absorption for even reverberation times so that an equalised response is in agreement with the subjective assessment.

Included are some useful graphics comparing system FR and distortion curves.

[Ian Mackenzie]

Studio Monitor Reference Chart

[Ian Mackenzie]

43XX profiles

[Ian Mackenzie]

Addition 43XX specifications

[Ian Mackenzie]

Additionally technical data on the 43XX systems

[Ian Mackenzie]

Additionally technical data on the 43XX systems

[Robh3606]

Looks like we have a winner!! One nice system 4313.

Rob