4333 help

[subwoof]

Ivica: Without delving into your response: I said (often) it makes NO difference what the *slope* is - if the distance from the driver exit to the eventual mouth is short, the crossover must be higher than a horn that is deeper.

Put a groove in it, cut a funky angled slit, poke holes with a rubidium laser in zero gravity, whatever....

Horns of the SAME depth that have DIFFERENT slopes/mouth area/curves/bends/girlfriends WILL require crossover slopes to match with the MANY variations of mid/woofer diameters and baffle placements.....and we are not even including the many driver variations.

But short is short. Long is long. If it didn't matter the long-throw 2366 was a waste of time right? it's 3ft+ deep for a reason. I use them each summer for shows and squirrels fear me.

You posted the infamous "Karson" horn which I believe has been debunked the same as his LF cabinet..but that's a DIFFERENT course of discussion....really...

The original poster has a single unloaded 4333 cabinet and wants to make/assemble a pair to use - but of course he has been swayed by the "4 way" crowd that extols the virtues of the additional low-mid cone. If he actually assembles a complete, component / crossover correct pair the midrange ( as explained quite well by heather ) will be JUST FINE and I have a pair in my study that get regularly abused by screaming vocalists of the "punk" genre.

The advantage by adding the 4th component is minimal BUT BUT is one of those " long-term engineer fatigue in the recording studio" issues that is applicable IN THAT CASE...hence the much higher cost and the MUCH more involved passive networks to keep that high SPL.

sub

[Horn Fanatic]

Hi subwoof,

Interesting explanations. Does that mean that any type of horn would have almost the same characteristics, and ONLY the length of the horn is important. If it that would be the truth the easier would be to put the pipe of the desired length. In such situation the if the length of the mentioned pipe (Lp) is equal Lp=Lambda/4, so Lambda=4*Lp, owing to the strong interference of the reflected wave cancellation would happen at the frequencies = (2k+1)*Co/Lambda ( k=0,1,2,.... ; Co speed of sound in the air, about 345m/s), and a kind of maximum would be at= 2k*Co/Lambda.

In the case of 2311 horn (including driver's internal horn of about 7cm) approximately Lambda/4= 17cm, so Lambda=4*0.17m = 0.68cm, that would correspond to about f=500Hz, second minimum would be expected around 1500Hz, etc. So using the driver&horn combo would not be good to be used under mentioned 500Hz frequency.

Using "HORN-RESP" calculator applying about 10W (12,6Veff) about 115dB/1m can be get, while diaphragm displacement would not be more then 0.2mm from the mentioned (500Hz) frequency (everything without applying high-pass filter, that has to be used, as mentioned on the 3133A network, -6dB is around 800Hz, the voltage on that frequency is reduced twice, relative to say 3kHz). As I have remembered (for JBL 244x drivers ) 0.5mm is a kind of diaphragm maximum displacement allowed.

All-in-all I think that 2311+2308 with appropriated driver such as JBL 2440/41/45/46/50 can be used, even in 4333 system.
Interestingly, using longer horn (while keeping the same mouth size) diaphragm displacement over 500Hz remains almost the same.

To be honest, I only know "Karlson coupler" type of 'horn' that is almost pipe-like (with the appropriated long slot), but it seems that such solution is not widely accepted.

http://www.diyaudio.com/forums/full-...n-coupler.html

Mr. John Karson patent US 3445852A has been an 'inspiration' for making Karlson-Couler, but not to forget Adolph Boehmen "SPRINKLER" patent US538861
[ http://www.google.com/patents/US538861 ] from the year 1895 ( May 7 ).

Some more theoretical explanation about Karslon coupler in acoustic can be find in:

http://www.cameng.com/pdf/the_k-coup...ransformer.pdf


I am aware that all above is just an approximation, but I believe that may be useful.

Regards
Ivica

I am touched that you posted my comment from the DiY forum about the Karlson sprinkler. Thank you. And thank you for posting the Martin Poppe paper for all here to see. I came across it about 25 years ago, and have created a spread sheet using his formula which allows me a great deal of design flexibility. The K-Coupler is indeed an exponential flare.

[ivica]

I am touched that you posted my comment from the DiY forum about the Karlson sprinkler. Thank you. And thank you for posting the Martin Poppe paper for all here to see. I came across it about 25 years ago, and have created a spread sheet using his formula which allows me a great deal of design flexibility. The K-Coupler is indeed an exponential flare.

Hi Horn Fanatic,

Interestingly that Mr.Karlson initially would not suggest exponential flare in his antenna patent presentation.
Unfortunately, I can not find any more Martin Poppe papers about K-coupler even he had said that more paper would come.

Just for the other forum members can get more about technical data about Karlson-Coupler
http://www.audioasylum.com/forums/hu...12/121068.html

Regards
Ivica

[Odd]

Ivica: Without delving into your response: I said (often) it makes NO difference what the *slope* is - if the distance from the driver exit to the eventual mouth is short, the crossover must be higher than a horn that is deeper.

Put a groove in it, cut a funky angled slit, poke holes with a rubidium laser in zero gravity, whatever....

Horns of the SAME depth that have DIFFERENT slopes/mouth area/curves/bends/girlfriends WILL require crossover slopes to match with the MANY variations of mid/woofer diameters and baffle placements.....and we are not even including the many driver variations.

But short is short. Long is long. If it didn't matter the long-throw 2366 was a waste of time right? it's 3ft+ deep for a reason. I use them each summer for shows and squirrels fear me.

You posted the infamous "Karson" horn which I believe has been debunked the same as his LF cabinet..but that's a DIFFERENT course of discussion....really...

The original poster has a single unloaded 4333 cabinet and wants to make/assemble a pair to use - but of course he has been swayed by the "4 way" crowd that extols the virtues of the additional low-mid cone. If he actually assembles a complete, component / crossover correct pair the midrange ( as explained quite well by heather ) will be JUST FINE and I have a pair in my study that get regularly abused by screaming vocalists of the "punk" genre.

The advantage by adding the 4th component is minimal BUT BUT is one of those " long-term engineer fatigue in the recording studio" issues that is applicable IN THAT CASE...hence the much higher cost and the MUCH more involved passive networks to keep that high SPL.

sub

+1

[hjames]

There is no Karlson horn in a proper JBL 4333.
I suggest you probably ought to keep the discussion focused on relevant support,
rather than take the OP on some wild and esoteric DIY technical discussions -
at least if you want to call it a 4333 rather than just "A Build in a Once-JBL Cabinet".

[ivica]

There is no Karlson horn in a proper JBL 4333.
I suggest you probably ought to keep the discussion focused on relevant support,
rather than take the OP on some wild and esoteric DIY technical discussions -
at least if you want to call it a 4333 rather than just "A Build in a Once-JBL Cabinet".

Hi hjames,

I am sorry if my several sentences 'diverge' from JBL 4333, but may be for some members that would be informative, may some of them for the first time have herded
about Karlson-Coupler, Most of my words are in close connection with my experience with the speakers such as JBL 4333.

Ivica

[hjames]

Hi hjames,

I am sorry if my several sentences 'diverge' from JBL 4333, but may be for some members that would be informative, may some of them for the first time have herded
about Karlson-Coupler, Most of my words are in close connection with my experience with the speakers such as JBL 4333.

Ivica

As polite as I can possibly be ...
Sure - its all geewhiz cool tech, but the Original Poster is trying to figure what to do with his single
old-style 4333 cabinet (with the overhangs top & bottom), and since he has asked for someone to
help with basics like creating a new baffle for him, I suspect esoteric cabinet mods/redesigns are
not a helpful direction for him to head down.

Consider that if the new guy is confused enough to want to make a 3 way design into a 4 way due
to an uninformed perceived midrange hole, the whole Karlson divergence doesn't gain him anything
but confusion, does it?

Perhaps you should start a new thread for cool tech like the Karlson cabinets and Horns?
I'll grant that it does seem like interesting stuff to read about, just maybe not in this thread.

Thank God Zilch and Bo and Subwoof stayed on topic when I asked for help while I was just starting
down the road with my 4320/L200B speaker build/redesigns. I went through sensible, repeatable changes
and learned what kind of sound I liked and where I wanted to go next with my gear.

There were only minimal distractions about Dodge and Mercedes trucks, and irrelevant technology.

[mech986]

Echoing hjames here - I don't know how or where you "see" or hear a midrange void. Most people complain that the 4333/L300 has abundant midbass and midrange, gobs of it, due to the high efficiency of the LE85/2420 driver and LE92/H92 horn - a must is to use the L92/2308 slant acoustic lenses to get the correct sound dispersion.

Have you truly heard a 4333 or L300 in proper running condition, appropriately internally wired to the correct crossovers and correct polarity to amps and each other? There will NOT be a midrange hole unless there is damage to the compression driver diaphragm, a fault in the crossover, or a wiring problem. There are some old polarity convention problems and anyone not familiar with JBL polarity issues in these older monitors might miswire the crossover and drivers. Also, since these drivers all use spring connectors instead of polarity matched connectors, its also possible to have drivers' polarity mismatched from one speaker channel to the other.

If there is a polarity mismatch from side to side, or side driver to side driver, you can get a suckout for that driver, and it will sound really phase-y and have no good center mono image. Output will be down as well as there is cancellation of the sound intensity. So it is possible to have midrange (and other problems) do to a poorly wired or maintained system.

Again, properly working, and properly wired and hooked up, the 4333 does not suffer from any midrange "void" issues. You would be well served to check the resources which tell you otherwise.

[grumpy]

might help for the OP to define what they mean by midrange...
if what is really meant is a mid-bass clarity issue (which one -might-
describe as a hole without having more to go on), it makes at least
a little more sense.