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alpina
06-26-2018, 01:13 PM
Hello everyone again ... I still enjoy all my JBL speakers here in Spain ... but I need a couple of woofers for one of my boxes 4425 and as we know it is difficult to find and more in my country. stock at a high price and I would like to know if there is an "equivalent" woofer to use at the moment while looking for a couple in good condition.

Earl K
06-26-2018, 01:46 PM
Worth owning is a pair of ( discountinued > so look for a used pair of )Beyma 12B100/R. (https://www.beyma.com/getpdf.php?pid=12B100/R)
- It specs out as Beymas answer to JBL's 2203H.

or ( somewhat less appealing since this speaker specs out more like a 2213H )

12BR70 (https://www.beyma.com/getpdf.php?pid=12BR70).

Either of those 2 Spanish built woofers should suffice as reasonable place holders.

:)

alpina
06-26-2018, 10:14 PM
Yes, indeed that B100 looks good even though I see this out of market ... I will try to find something in stock. Thanks

RMC
06-30-2018, 09:52 PM
Hi Alpina,

Some of the relevant T/S parameters of the 2214H (original 4425 woofer ) for better acoustical matching in the box may help you in your seach for a replacement driver: Fs 23hz, Qts 0.24, Vas 224 L., Xmax 6.6 mm, Re 5.6 ohms, No 1.1% and sensitivity 91 db/w/m.

Looking at Earl's suggestions, I agree the first is the more desireable of the two, not ideal just reasonable as he says, but discontinued.

Leaving sensitivity and baffle cutout aside for the time being, you can see from the TS even the first one could preferrably be closer to 2214H specs to minimize difference in sound. Plus if foam edges can be avoided the better for longevity and the work involved in refoaming, been there done that and its a pain, specially when the foam inside the woofer's rear vent hole is rotten too, has migrated and needs to be taken out...

If you're the type who likes to push it in terms of power input, the small Xmax number of the first suggestion (3 mm) is far from that of a real 2214H, which means you would get into Low Frequency distortion much sooner.

As for the second suggestion, its rubber surround lasts much longer and the Xmax at 8 mm are very nice, however some of its TS are much further away when comparing Fs, Qts (0.50 !!), Vas, No, etc. to the original. I would try to avoid this one.

I understand Earl tried to provide you with some suggestions close to home (Beyma being in Spain) and thats fine. But you can still search in Europe using the same Euro currency and maybe find a more suitable candidate.

Personnaly, I would look elsewhere than these two (one discontinued and one too far off) to try to find a better match. Being in Europe you have a LOT of driver manufacturers to look at: RCF, B&C, 18 Sound, etc. (more expensive), and others that require less money like Tymphany (Peerless, Vifa, etc.) and SB Acoustics just to name a few. Regards,

Richard

alpina
07-02-2018, 03:36 AM
hello. Yes, indeed the model 70 seems short since, for my part, I like to raise the potentiometer since I have speakers for it ... I keep looking at options. Thanks

RMC
07-03-2018, 02:24 PM
Hi Alpina,

I did a search for myself (and you), since I also may have to replace drivers one day, in order to find an acceptable replacement for the 2214H.

First I looked at 12" woofer specs/TS from the following manufacturers: RCF, B & C, Beyma, 18 Sound, Faital Pro and Fane Acoustics, all of which are from Europe plus well known Pro sound driver manufacturers. The results were not satisfactory in the present context, some prospects were discontinued, or because of too high Qts and/or Fs and too low Vas for the given box (4425).

Then I switched to more Hi-Fi manufacturers I previously mentioned. Beginning with SB Acoustics of Denmark. Bingo! I have found there a pretty good candidate to replace a 2214H, not an exact clone but more than reasonably close on many aspects. You can check it on sbacoustics.com. Model # is SB34NRXL75-8. Be careful as there is another model with very similar but not exact same number, and that other model is less desirable...

For start, this prospect has a rubber surround with much longer life than 2214H foam. Nice. Following are a few specs/TS for the SBA woofer and in parenthesis I put the equivalent 2214H data:

Impedance 8 ohms (8), Le 1.2 mh (1.3), VC 75 mm (75), Xmax 10 mm (6.6), Flux 1.1T (1.07), Fs 22hz (23), sens. 91 db (91), Qts 0.28 (0.24), MMS 93 gr. (90), BL 16.6 (16), Vas 205L. (224), rated power 200W (200).

I put driver DC resistance separately here because it requires some explanations: SBA Re 6.2 ohms (5.6 JBL 2012 T/S Table). But that JBL number appears to be the middle of the range since in the JBL L100T Tech Manual using the 2214H, woofer DCR min./max. is given as 5.1 - 6.3 ohms, and in the 4425 Tech Manual the 2214H woofer DC resistance is given as 5.7 ohms plus or less 10% (giving 5.1 - 6.3 ohms again same as L100T). So the SBA driver at 6.2 ohms would fit the range, providing its own tolerance is ok. (By the way the 2214H-1 with Aquaplas in the L100T3 has the SAME DC resistance range of 5.1 - 6.3 ohms as per Tech Manual 06/91).

As you can see above, specs wise the SBA driver is generally quite close to 2214H. The item that concerns me just a little bit is the little higher QTS and its effect on LF box response or size needed. I don't expect a big issue here but we'll see if I model it later in speaker design software using a box equivalent to 4425 (Vb 53.8 L, Fb 34 hz, as per JBL data sheets 01/86 and 7/93).

The SBA driver drawback is the baffle hole cutout of 305 mm VS 281-2 mm for my 2214H. This 24 mm or so difference may not be a major problem if removing 12 mm all around the present 2214H/4425 baffle hole. Measure precisely the present hole diameter to see what you have exactly, then can calculate what you actually need to remove with a jig saw to fit the new driver (first make sure nothing is in the way of a larger hole perimeter inside or outside the box).

The SBA woofer mounting depth indicated is 146 mm, the 2214H I measured is 135-6 mm (without gasket). So SBA woofer has 10 mm more depth which in most cases should not be a problem.

BTW in Canada this SBA woofer sells for $325. CAD (solen.ca), but being imported here I assume it would cost less in Europe. Also, there is probably a sizeable currency exchange effect in that Canadian price since the CAD is worth much less than the Euro. The 12" Pro drivers I looked at previously were often selling here in the $300-400+ CAD, and were much less suitable than the SBA.

I'm not finished yet looking at Peerless woofers data (Tymphany.com) to report on. Also when I have time I want to run the SBA woofer in speaker design software to see how it performs in the same Vb/Fb compared to the 4425/2214H. Regards,

Richard

P.S. I will be out for a week of vacation from July 7 so don't expect any reply from me during that time.

P.P.S. Almost finished writing this and I looked into my own speaker building projects binder where I keep my boxes info/data and some driver searches done, and found a paper of a previous search I did for 12" woofers (some Pro but most hi-fi) three years ago (not only for 2214H replacement). I had completely forgotten about that search I made since I do a few. On the hi-fi side of the prospects list the names are Dayton Audio, Hi-Vi research, Peerless and SB Acoustics. Guess what? The SB Acoustics # SB34NRXL75-8 mentioned above is on the list plus was a top contender! At the time I noted it sold for $315. CAD and I have a note regarding baffle cutout size required... So the old man is pretty consistent I guess!

Ian Mackenzie
07-03-2018, 03:32 PM
http://www.visaton.de/en/products/woofers/w-300-8-ohm

http://www.visaton.de/en/products/woofers/tiw-300-8-ohm

Ian Mackenzie
07-03-2018, 03:45 PM
https://m.ebay.com/itm/JBL-2214H-Woofers-Pair-JBL-L100T-JBL-4425-/183290495610?oid=223013287904

Ian Mackenzie
07-03-2018, 05:51 PM
This is probably a bit out of scope but would be an interesting alternative driver for a diy 4425 project

I have no personal experience with this particular driver but l haves used the TD15M.
They are very low distortion drivers. The 15H is reported as superior to the 2235H so the TD12H potentially a nice driver. Lots of copper and aluminium in the motor.

http://aespeakers.com/shop/td/td12h/

Either the H or X version would work.


TD12H-8ohm
Fs: 26.7Hz
Qms: 3.72
Vas: 160 L
Cms: 88.6 g
Rms: 4 kg/S
Xmax: 14 mm(peak)
Xmech: 18 mm(peak)
Sd: 530 sqcm
Vd: 1.48L (p-p)
Qes: .25
Re: 6.5 ohm
Le: .3 mH
Z: 8 ohm
Bl: 19.7 T/m
Pe: 500W (cont.)
Qts: .23
1WSPL: 92.9 dB
2.83V: 93.77 dB

alpina
07-04-2018, 03:51 AM
Thanks for the contribution ... but there is an important question in the case of prices for equivalent components ... I have informed and can get new 2214H, here in JBL technical service, at a price of 800 euros the couple ( brand new) but you have to wait a while to be able to have them, since I suppose they have to manufacture them.
That said ... for prices of 300-400 plus shipping it is better to buy the new 2214h at that approximate price of 800 euros, I think.
PD:
I respect the purchases of ebay, for example, usually sold on 300 euros + 120 aprox shipping to Spain ... this must be added, almost always, a new suspension or something else. In total, makes a sum Approximately 600 euros placed in my house and in theory working properly ... I'm not interested in buying this type of woofer in the US where it is usually sold on ebay or similar.


I'll wait a reasonable time to see if I can get a couple of 2214h at a decent price-state and if not, I'll look at the ones posted here as equivalent.

RMC
07-04-2018, 03:19 PM
Hi Alpina,

RE: "but there is an important question in the case of prices for equivalent components ..."

I realized that right from the start since you mentioned in post # 1 "stock at a high price and I would like to know if there is an "equivalent" woofer to use at the moment..." This is why I also indicated from the beginning lower cost brand names such as Peerless and SB Acoustics. I know I have drivers from both of these brands too, among many others. In addition, the $300-400 drivers mentioned were mostly from the Pro group I checked and they were not satisfactory specs/TS wise for the present case.

BTW, Canada and USA prices are usually plus taxes, whereas in Europe the VAT (value added tax) is often included in prices. That has to be kept in mind when making comparisons.

I agree with you about the E-Bay thing. However, I think you misunderstood post # 6 regarding pricing info I gave you about the SB Acoustics driver, or maybe you are less familiar with foreign currency dealings. The $325. is Canadian dollars (CAD), not US dollars, and the Canadian dollar is worth less than US dollar. Moreover, the Canadian dollar is worth even less VS the Euro... In practice this means the Canadian price of $325. is overinflated by the lower CAD currency exchange value.

I'm not suggesting you buy the drivers in Canada nor in the USA. If you purchase the SBA driver in Europe with Euros there is no inflated price due to currency exchange. My impression is that by purchasing in Europe with Euros you may be able to get the SBA driver for somewhere around 200+ Euros each (depending on VAT, and shipping?). Just look around in Europe to see what would be the price for the SBA driver. Maybe you can purchase in a European country close to you where VAT/shipping cost is lower?

As for the Visaton woofer suggestions you were given, the lower cost Model W 300 certainly doesn't pass the test, no surprise here. Its not equivalent, nor really suitable or acceptable globally since too many of its specs/TS are off compared to a 2214H for 4425 use.

With regards to the other TIW 300 suggestion, this one looks better, though still notably short on Vas, has a similar issue as the SBA re baffle cutout, but it is much more expensive in Canada, than the SBA, at $457. CAD. I assume it will be more expensive in Europe also...

As for the TD-12, the $329. starting price is more expensive being in USD (35% more than CAD at today's exchange rate at the bank), plus shipping cost to Europe... Also short on Vas, some others are a little off in the present context.

My Peerless 12" driver search is over and has returned nothing interesting or worth mentioning (TS generally too far off). Too bad because in the past they used to have some interesting models (I have a pair of 12" Peerless). Therefore, it seems your best bet remains the SBA.

Regards,

Richard

EDIT: The Visaton W 300 appears to have a foam surround while the TIW 300 seems to have a more desirable rubber surround for longevity. The SBA driver suggested has a rubber surround also. The 2214H definitely has foam surround, I own a pair of these drivers and had to refoam them.

Ian Mackenzie
07-05-2018, 08:26 PM
Hi Alpina,

Regards what you do any suggestions needs to be weighed up against your required effort (such as enlargement of the woofer mounting hole - a non reversible decision), financial outlay and how fussy you are about the replacement woofer?

I read in your earlier thread you had a Jbl 2206 in a 4425 system.

Some context from you of the 4425 you are replacing the woofer for will focus any suggestions.

For example if you are a collector or a Jbl buff then perhaps only a new pair 2214H will do.
Buying drivers off eBay is fraught with danger.

Alternatively if you were keen to try other drivers and be flexible in re tuning the enclosure that is another pathway .
Beyond the basic TL parameters the geometry of the cone, the surround geometry and the cone material all combination to impact on the sound of the driver particularly if used in a bass midrange application. Paper cones vary considerably in the pulp used and in combination with other fibres and coatings.

A point to appreciate is the 4425 has a carefully designed crossover network that is tailored to the specific characteristics of the woofer and the horn/ compression driver. The whole thing it set up for seamless blending of the drivers.

Any alternative driver is going to require some adjustment of the network for it to work per the original design. That will require some technical expertise.

My suggestion would be to contact Rich in the UK and Guido in Europe who both have lots of experience with building and restoring Jbl systems.

alpina
07-06-2018, 01:28 PM
Hola de nuevo ... Realmente me gustaría colocar sus woofers originales (me gusta la originalidad y no entiendo mucho para jugar con filtros ...) realmente ese beyma B100 me gustó porque incluso se ve físicamente en 2214 y podría parecer "original" "y el 4425 los restauré y me gustaría encontrar el 2214, por lo tanto, en este momento, esperaré un tiempo para buscar.

Había montado el 2206 porque compré mi 4425 sin woofers y este modelo anterior es más fácil de encontrar. .

RMC
07-06-2018, 08:49 PM
Hi Alpina,

RE: "that beyma B100 I liked because it even looks physically at 2214 and it could seem "original"."

I can understand your concern for driver appearance, though there's a speaker grill hiding the driver...

If it looks nice but doesn't sound correctly what is the point for a speaker. Selling it as a "real" 4425?

I never build a piece of furniture, I concentrate on an acoustically sound box.

Personnaly I'm much less concerned about appearance and looks, than acoustical performance. I guess that's a matter of priorities or personal preferences.

Just in terms of appearance, those who know the 4425 and/or the 2214H driver would not be fooled by the Beyma driver since, for example, it has a 4" voice coil and dustcap accordingly (JBL 3"), the foam roll surround of the 2214H is wider than the Beyma and the JBL has a deep cone. These would tell immediately.

I would recognize right away this isn't the original woofer... not even mentioning the woofer's sound.

The Beyma also has a minor baffle cutout issue in addition to the T/S issues.

In case you want to look at another driver just for curiosity, I've found another one of some interest: Fostex FW305. Apart from sensitivity/power handling (the other side of the coin), the Fostex looks relatively good, just a bit short on Xmax. However, it sells for $400. or so in Canada, so again more expensive than the SBA.

Regards,

Richard

johnlcnm
07-07-2018, 11:35 AM
Alpina,

Look at the JBL SR 4722a. Same horn and driver and hi freq. crossover as the 4425. The pads have been eliminated and the crossover resistors have the PRO power dissipation levels. You could duplicate the low crossover section for the 2206s, and use the 2206. I am using the 2206s in my pair of 4425s. I think it is a much better sounding driver then the 2214h. I am not a 2214h fan in the 4425 box. In the 4425 cabinets they have a case of bass bloat in my sound space. The 2206s do not, and make the bass drum sound much more realistic IMHO.

alpina
07-09-2018, 04:21 AM
The 2206h is best that 2214h,yes.. But I have sold it for some time.
I have decided, without haste but without pause, to buy your used or new 2214h ... I will see. I have enough music to listen on my other devices and it is always more profitable to sell with original components in the supposed case.
I'm also thinking about another project to do at home ... and as they say, rushes are not good !. Anyway, I have saved the suggestions written here as they come in handy for those other projects. From here, my total gratitude.

RMC
07-15-2018, 08:18 PM
Hi Alpina,

RE: "The 2206H is best"

Best for what purpose? Every driver is developed with an intended use in mind. The 2206H was optimized for high power/level sound reinforcement, whereas the 2214H was optimized for high fidelity/studio monitoring purpose in mind. These are two different ball games. Sure a 2206H would still produce sound when used in a 4425 cabinet, maybe even acceptable sound to some, but it was not optimized for critical listening in a studio monitoring environment or for home high fidelity as the 2214H.

Because the 2206H has the JBL name on it and its baffle cutout is 280 mm VS 281-2 mm for 2214H its an appealing and convenient drop in easy fix, physically speaking. But there's a lot more to it than that. Appearance wise, the 2206H's cloth surround, 4" voice coil/dustcap and cone depth betray the woofer's non-original status.

On the technical side, though some of the 2206H electrical parameters (e.g. LE, RE) seem acceptable, some of the important box related parameters are not even close to those of a 2214H: Fs 52 hz (23hz), Qts 0.32 (0.24), Vas 62 L (224 L); sensitivity 95 db (91 db), a notable 4 db difference which would put the 2206H sound forward compared to the rest of the 4425 system.

In the 2206H spec sheet the suggested box is Vb 57 L /Fb 50 hz. In the 4425 spec sheet using 2214H the box has Vb 53.8 L/Fb 34 hz. The 2206H box has a little larger volume but a MUCH higher tuning frequency and an F3 at 50 hz, so forget about low bass in that case...

My initial impression was that dropping in a 2206H in a 4425 box would likely yield a small bass bump because of higher driver Qts and a little smaller box volume. But then the combined effect of much lower box tuning frequency of the 4425 would also kick in creating a dropping low frequency response.

So I've modeled quickly the 2206H in Winspeakerz software with the 4425 box parameters given above. The result is poor, as expected, with a pretty dropping response in the low end (from 150 hz down), unless one would use 2-3 boundary box placement: -5db/50hz, -7db/40hz, etc. Morever, above 150 hz the response is at +2db. How do you think this box would sound? Likely weak bass, strong low-mid and a general driver level higher than it should in view of its 95 db sensitivity VS 2214H/4425 91 db.

Re-tuning the box higher for better 2206H driver performance in that box would imply shorter vent tube and/or increasing vent diameter, the latter not a practical change to revert back to the previous situation, specially with particle board.

That being said, I don't necessarily agree with an earlier statement made here that an increase in baffle cutout (and/or vent area) is non-reversible (across the board). I've done it a couple of times with success to avoid scrapping good boxes. But then ALL my speaker builder boxes are made of plywood for a number of reasons...

Richard

Ian Mackenzie
07-16-2018, 04:58 AM
http://www.audioheritage.org/vbulletin/showthread.php?2772-JBL-12-quot-Woofer


https://reconingspeakers.com/product/jbl-lsr32-252g-12-speaker/

Apart from being a 4 ohm driver it’s an excellent driver as used in the LSR 12 inch system

Some basic re design of the low frequency network and you are done

johnlcnm
07-18-2018, 11:29 AM
RMC. I agree with your analysis of the 2214 and 2206 parameters. The 4425 ports are tuned to 40Hz. The measurement plot shows a check mark response down to 40Hz, which was expected. 50Hz would probably give a flatter response, but I do have a 60Hz resonance in my room which seems to counteract the lull at 60Hz. I will have to look for the waterfall bass response plot. I did kill the LF section of the existing crossover network and build a separate LF network for the 2206. Could use more work/experimentation at this point for sure. I never thought of using the 252G. Could have been purchased maybe for the same price as the 2206s I obtained.81777

Ian Mackenzie
07-18-2018, 12:44 PM
The 4425 was tuned to 34 hertz

See page 2 in this link

http://www.jblpro.com/pub/recording/4425.pdf

johnlcnm
07-19-2018, 10:24 AM
My measurement. I think I made the measurement with the 2206s. Could be the volume difference between the 2214 and 2206, or cal error in my equipment.

Ian Mackenzie
07-19-2018, 01:46 PM
No worries.

The 1200H used in the Century Gold (1.8 cuft3) is tuned to 32 hertz.

johnlcnm
07-20-2018, 08:17 AM
I went though quite a journey with the 4425's. They had a resonance somewhere around 2kH to 3kH. I replaced the high frequency compression drivers with the commercial 2426H's loaded with new Radian diaphragms. Did not solve the resonance issue in the upper midrange. The problem was the 2214H's. Replacing them with the 2206H's solved the problem. Also improved the midrange considerably. IMHO the 1200Hz crossover is a little high for the 2214H's. Their first breakup mode is just too close to that crossover frequency.

No doubt the 1200FE-8 is a much better driver then the 2214 or the 2206 for a small home system. I also have the 4429's in my main system. The 1200FE-8 not only has excellent bass, but a very good lower midrange. My fav. JBL 12 incher. A really great driver.

RMC
07-22-2018, 11:19 AM
Hi John,

RE: The 4425 ports are tuned to 40Hz; Could be the volume difference between the 2214 and 2206


I don't see how a new and original 4425 box could be off this much (Fb 40 hz VS 34 hz or 18% more) from the factory, unless they installed wrong tube(s) lenght ? Do both boxes have the same Fb 40 hz?

However, If the boxes were purchased used, could be a possibility a previous owner replaced or even shortened the vents to re-tune the box higher for better performance with a driver different than original? Have you checked/feeled the tubes' cut at the inside end of the boxes to confirm a smooth as a machine made factory cut or can you feel with finger(s) some signs of another tube cut made? Do vent tubes have all the same length?

Checking the low-frequency impedance curve of the 4425 in the original spec sheet dated 01/86 and in the subsequent one 7/93 (to assess if Fb 34 hz a typo?), confirms the minimum impedance point between the two LF impedance bumps appears located at the right place on the graphs. So 34hz doesn't seem a typo.

JBL 12" drivers from that period of time are regularly described as having a "volume displaced by driver" of 4 L. or 0.15 cu.ft. I don't see where the 2214H and 2206H can be so different in size so as to explain such a shift in box tuning frequency from the expected 34 hz to 40 hz. I assume a tolerance of a few hz is acceptable.

Another way of looking at this driver volume displaced issue and its effect on Vb/Fb could be the following. According to Electro-Voice, box volume "Variations of + or - 5% of the specified net internal volume will not materially affect performance." (Pro Sound Facts, No. 7, Oct. 1984, P. 7) I tend to think the shift from Fb 34 hz to 40 hz is material, more so in the context of a studio monitor/critical listening application for example.

On the other hand, the net box volume of the 4425 is 53.8 L., so 5% of that volume = 2.7 L. or so of tolerance. And we know the volume displaced by JBL 12" drivers of that era is of the order of 4 L. as per "JBL: Conversion constants and Useful Data", along with some data sheets: e.g. 2206H, 2204H, 2202H.

Therefore, this would mean box performance is materially affected when greater than 2.7 L. or so, on top of the 4 L. or so already factored into Vb, is in effect: 4 L. + 2.7 L. = 6.7 L. Is the 2206H, or the 2214H for that matter, that much larger (6.7/4 = 68%) than the other? In my book that's a NO. Even more so knowing the volume displaced by a 15" driver of similar era is 6 L. based on JBL data... Even putting the 2206H at a fat 6 L. (which is not real), it wouldn't justify the Fb shift here, and that's the volume taken in the box by a 15"!

Driver size difference mentioned here, and its possible effect on Vb/Fb, a feasible explanation re tuning frequency shift? It sure doesn't appear to be the likely reason in this case. If vent(s) modification doesn't explain it, then measurement method or calculation error would seem to be the likely cause among those mentioned. Regards,

Richard

P.S. Another possible cause could be more than usual box losses (QL) and their impact on effective box Vb, and by rebound on Fb? This could also be part of the explanation...

EDIT: Regarding the above P. S. note.

RE:"I did kill the LF section of the existing crossover network and build a separate LF network for the 2206."

"2214H's. Replacing them with the 2206H's"

"I replaced the high frequency compression drivers with the commercial 2426H's loaded with new Radian diaphragms"

The original compression driver of the 4425 is 2416H as per JBL Data Sheet and Technical Manual.

With all due respect, considering all these changes made to the system what you really have is sort of a "Frankenstein" 4425 system. This gives me the impression that in the making maybe the original box air tightness has been somewhat compromised?

For sure an Fb 40 hz gives a little better response with a 2206H in a 4425 box (vs Fb 34hz), but still short from an Fb 50+ hz in terms of response flatness, as seen in Winspeakers modeling software.

johnlcnm
07-22-2018, 03:27 PM
Richard,
It has been a while since I made that measurement. It was definitely a small signal measurement. 100 Ohm resistor in series with the signal generator, and VOM across the speaker input. I guess that would be referred to as a down and dirty measurement. I am going to make that measurement again. This time no resistor and through an amp. I'll feel for cone movement. Will report back! At the time I had the data sheet, but didn't look for the box resonance. I know that a small signal measurement can be different then a large signal measurement.

Regards,

John