K120 re-coned with McKenzie kits

[ivica]

Interesting (for me) that about other JBL drivers it is possible to find some "real" measurement data, but for 2202 A/H I could not find anything about.
I have find about "similar" Altec 414: http://sites.google.com/site/drivervault/driver-measurements/tang-band-75-1558se/gpa-altec-414/frequency-response
but that one is 3" VC.....and the internal construction may be different.
Here are some measurements done with mentioned K120 re-coned with "McKenzie" re-cone kits for 2202H driver.
at 30deg off axis ,
at 15deg off axis ,
at 0-deg (on axis), .

response grid is 2.5 dB

[ivica]

Interesting (for me) that about other JBL drivers it is possible to find some "real" measurement data, but for 2202 A/H I could not find anything about.
I have find about "similar" Altec 414: http://sites.google.com/site/drivervault/driver-measurements/tang-band-75-1558se/gpa-altec-414/frequency-response
but that one is 3" VC.....and the internal construction may be different.
Here are some measurements done with mentioned E120 re-coned with "McKenzie" re-cone kits for 2202H driver.
at 30deg off axis ,
at 15deg off axis ,
at 0-deg (on axis), .

[ivica]

Interesting (for me) that about other JBL drivers it is possible to find some "real" measurement data, but for 2202 A/H I could not find anything about.
I have find about "similar" Altec 414: http://sites.google.com/site/drivervault/driver-measurements/tang-band-75-1558se/gpa-altec-414/frequency-response
but that one is 3" VC.....and the internal construction may be different.

But if response curves are 'pondered' by 'directivity' ( for 12" driver that stat say from 430Hz with 6dB/Octave ) , what I expect that is proportional to emited energy, it can be get for E120 basket and K120 basket with "McKenzie" 2202H kits.
Blue is not pondered response, and red is pondered, and green is 'ponder'

[speakerdave]

Out of respect for Mr. Lansing's memory and as beneficiary of the work done by him and those who coming after him have endeavored to work to the highest standards of engineering and production quality, I'd like to see this discussion ended.

Kits for the 2202 are still available, I believe.

Although there may be some legitimate interest in the poster's project as regards drivers that have been abandoned, if a driver is still being supported by JBL, discussion about aftermarket recones is entirely out of place on these forums, and the reason is ably illustrated by these graphs, which seem to represent an unusable driver and are accompanied by no supporting information regarding the testing method and the conditions under which they have been done.

[Robh3606]

Although there may be some legitimate interest in the poster's project as regards drivers that have been abandoned, if a driver is still being supported by JBL, discussion about aftermarket re-cones is entirely out of place on these forums,

Well I understand where you are coming from. I have done my own aftermarket measurements and had similar results to the ones posted. I see it as reason to stay away from the aftermarket kits if only because you don't know what you are getting.

That said I am moving this out of Technical and into DIY. Any aftermarket kits are just like re-foams and are DIY IMHO

Rob:)

[ivica]

Well I understand where you are coming from. I have done my own aftermarket measurements and had similar results to the ones posted. I see it as reason to stay away from the aftermarket kits if only because you don't know what you are getting.

That said I am moving this out of Technical and into DIY. Any aftermarket kits are just like re-foams and are DIY IMHO

Rob:)

Mr. Robh3606, You, as Administrator, can delete my posts if You think that is out of Forum interest, or in any case would "produce bad feeling" to
the members.
My final idea is to make some 4345 clone but with 2202H instead 2122H, so, you can put my posts at the place where, with your large experience, you think is much more appropriate.
May be for "TECHNICAL" part, you can find and put more reliable data about 2202 A&H, so can be useful for the members....

I will be more then happy, if I can find real 2202A/H response measurements, not extremely smoothed as, I believe had been done on JBL documentation for 2202A and 2202H.


With mine measurements I want to show:

1. what can be get from not so expensive re-cone kits, that are about 4~5 TIMES less expensive.
It is reasonable to expect that such can not overcome originals. What would be nice if the original one, is flat on axis, but with large dispersion angle too, off-course operating till 5-6kHz without notch and bumps.

2. I want to emphasis that AF kit as standard 'construction' behaves as expect-able RIGID PISTON RADIATOR of appropriated size, until the cone "break-down" happened (over 3kHz).

3. but if we are interesting about the emitted energy, what from my point of view, would be equivalent as spacial averaging "over" much larger angle then 0 deg, then the response that can be get would be much different.

One think is very important to see is expect-able response on 45 deg 'off axis' angle that is documented on the presented JBL data in:
http://www.audioheritage.org/vbulletin/showthread.php?9531-2202A-verse-2202H&p=321674&viewfull=1#post321674

[ivica]

Out of respect for Mr. Lansing's memory and as beneficiary of the work done by him and those who coming after him have endeavored to work to the highest standards of engineering and production quality, I'd like to see this discussion ended.

Kits for the 2202 are still available, I believe.

.......

I am very sorry if all of my "work" can, on ANY circumstances, be understand as any kind of disrespect of Mr. Lansing and the other leading engineers at JBL, and their work.
But, just opposite, these data in comparison with original 2202A/H, would be nice thing that (as i expect) would show how JBL product are superior to AF products.
Unfortunately, I could not get any 2202A and 2202H, 'real' measurements.

My budget, nowadays, is such that I can not afford over 600 $ for one pair of 2202H re-cone kit (C8R2202H), but soon such would not be available any more, concerning the Harman-JBL "politic" in related with old JBL driver spare-pats.
I believe that you know that re-cone part: C8R2202 was priced 148U$D in the year 2002., and in year 2011 is 240U$D, and

Just as an information here in Europe in :
http://www.thomann.de/de/jbl_c8r_2202.htm

the price for SINGLE re-cone kit C8R2202 is (287 evur ) ~ 390 U$D.:eek:

[1audiohack]

Here's what I get.

This is a used 2202H in a sealed 1 cubic foot test box with no fill, the ripple at 525Hz is the box. Baffle dimensions are 26" tall X 30" wide, the driver is on center, swept on a 6' tall acoustically transparant stand. Gated data is rock down to 190 Hz and believable to 95 Hz. Phase deleted from first graph for clarity. 1/3 octave smoothing to protect the innocent.:p

Hope this helps.

All the best,
Barry.

[ivica]

Here's what I get.

This is a used 2202H in a sealed 1 cubic foot test box with no fill, the ripple at 525Hz is the box. Baffle dimensions are 26" tall X 30" wide, the driver is on center, swept on a 6' tall acoustically transparent stand. Gated data is rock down to 190 Hz and believable to 95 Hz. Phase deleted from first graph for clarity. 1/3 octave smoothing to protect the innocent.:p

Hope this helps.

All the best,
Barry.

Many, many, thanks Barry, for Your intensive and precise work. I think that has to be copied into "Technical" part in connection about 2202 driver. This is the first so detailed measurements of 2202H driver I have ever seen.

So combining your measurements with ORIGINAL JBL2202H, a mine E120 basket "re-coned" with McKenzie 2202H kit I get this figure. Concerning that I have no appropriated box, my data under 600-700Hz has to be neglected.

I think this comparison easily show the differences between the ORIGINAL and AF products.

On "the first look" it is visible that the Original has about 1kHz wider HF bandwidth (with "cut-off" on about 4kHz, while on AF one, the "cut-off" is on about 3kHz, and smoother in the "pass-band".
One one interesting thing (for me) is that even the original is "falling-down faster at 45deg off-axis", after 2kHz its directivity remains constant till 4kHz, what I think is not expect-able for so large voice coil (4") driver, and may be show JBL designers skills.

[ivica]

Finally, after some time I have got JBL 2202H recone kit (C8R2202) and 'put it' into E120 basket.
With attached figures it seems to me that it behaves almost identically as Barry's original 2202H.
For the comparison the same basket with McKenzie 2202H recone kit is presented here.
Concerning the last mentioned kit (McKenzie) I have realized some things:
1.The length of the VC is almost the same, but McKenzie VC goes about 2.5mm deeper into top plate then JBL one. I think technicians from McKenzie have to "re-tune" their Jig for 2202 kit., in order to move static VC position about 2.5mm (0.1inch) more out off the top plate then what is now the case.
2. I think (from my feeling) that McKenzie spider is stiffer then the JBL (it is visible on the LF behavior in the measurement too). I am not sure but may be such stiff spider is the (provocative) reason for large peak in FR around 2.2kHz when McKenzie 2202H re-cone kit was used.

Concerning that I have no appropriated box, my data under 600-700Hz has to be neglected.

[4313B]

My final idea is to make some 4345 clone but with 2202H instead 2122HNot a problem. Use the 4355 network instead of the 4345 network and bi-amp between the 2245H and 2202H.
Finally, after some time I have got JBL 2202H recone kit (C8R2202) and 'put it' into E120 basket.An E120 core is going to generate higher Bl than the 2202A, K120, 2203A, 2203H, 124A, 124H or 2202H cores due to its increased flux density.

[ivica]

Not a problem. Use the 4355 network instead of the 4345 network and bi-amp between the 2245H and 2202H.An E120 core is going to generate higher Bl than the 2202A, K120 or 2202H cores due to its increased flux density.
Well, yo are right, but I do like too many amplifiers, electronic-crossovers, per-amplifiers...., in order to listen "every-day", especially,
if some not to much technically oriented other member of my family want to use it.
From my point of view some kind of 'beaming' of 12-inch driver -over 1kHz is one think that make me 'wonder', and on the other side if I would put
24xx driver with 2311+2308 'side-by-side' with 2202, I am 'afraid" that some other problem can arise in 'beaming and notching' behavior in horizontal plane