JBL 2245H vs 2241H vs 2242H vs 2235H vs TAD 1601 Performance over the 30hz - 200Hz

[dkalsi]

Hi All,

I'm just messing around with some gear and I wanted to get the experts opinion on the following:

Basically - I'm looking for a bass bin that would provide good musical bass over the 30Hz - 200Hz range.

I'm really not concerned with performance above 200Hz as I will be crossing over to a full range driver above 200hz. In my application, higher the efficiency, the better for me.

When searching craigslist, one can easily file DJ/club gear where bass bins with dual 15" or dual 18" are being employed.

For example - one can find a JBL SR4719X with dual 2241 pretty cheap (relatively speaking).

Are these drivers not considered "musical" or "audiophile" enough? Ultimately, I don't want to spend alot of money trying to obtain TADs or AE TD15 or even the JBL 2235H, when one would not be able to tell much difference between the performance of these speakers over the 30hz - 200hz range.

Any thoughts?

[Lee in Montreal]

Pretty sure that it was answered 100 times before ;-) Look below. Similar threads. ;)

[Mr. Widget]

For 30-250Hz, I would definitely go with the 2245 if 10 cu ft isn't a problem.
How about a K/E145 between 50 and 300Hz? Add the small powered sub of your choice to drop below 50Hz?

What is your "full range" upper range device?


Widget

[dkalsi]

Pretty sure that it was answered 100 times before ;-) Look below. Similar threads. ;)

Ha - duly noted - will do a little more search.



For 30-250Hz, I would definitely go with the 2245 if 10 cu ft isn't a problem.
How about a K/E145 between 50 and 300Hz? Add the small powered sub of your choice to drop below 50Hz?

What is your "full range" upper range device?

Widget

Just bought a pair of Azurahorns - was going to try and combine them with Tang-Band 1808 8" full range drivers. The horns & driver combo can apparently play from 150hz - 20,000hz.

I plan on crossing the horns to the bass bin at 200Hz.

In regards to the box size, the 10 cubic feet may be bit large.

For now, I might just use my JBL W15GTI subs (3.5 cu.ft. sealed) for the 30hz - 200hz for the sake of avoiding the need to build something in the near future. I can't remember where I saw the response curve, but I think the JBL W15GTI is relatively flat to 200hz.

Part of the reason why I was considering the subs listed in the title of this thread is because they are so readily available used on CL.

[Lee in Montreal]

I can't remember where I saw the response curve, but I think the JBL W15GTI is relatively flat to 200hz. The W15GTi has a very heavy cone. I don't know if it can really do 200Hz. Remember that it's primary use is in boom cars. It's not a musical woofer. One note bass. But I am sure it will give you great 20-80Hz ;)

[dkalsi]

The W15GTi has a very heavy cone. I don't know if it can really do 200Hz. Remember that it's primary use is in boom cars. It's not a musical woofer. One note bass. But I am sure it will give you great 20-80Hz ;)


Thanks Lee - You're probably right. I have them crossed a 80hz with the EQ around 20Hz.

Haven't tested their performance beyond 80Hz though.

I found the following measurements for W15GTi in "35V infinite baffle, measured inn an anechoic chamber"

58383

Once I build everything I need for the horn - I guess it would not take much for me to sit them on top of my 1) JBL W15GTi subs, or my 2) DIY 4345 and use the 2245H

[Lee in Montreal]

The 2245 remains, in my opinion, a very good musical subwoofer. You can easily make a 36" x 23.75" x 23.75" cabinet from one single sheet of plywood, plus the bracing. The rear corners can even be cut at 45° to avoid standing waves. That's 11.5cft and it could easily fit under the television to make a 2' tall stand. Some people think a 2245 is so generous infra bass that it shouldn't be put in a room corner. So, right in between under the television seems right ;) Also, if you use a sub to complement a bass horn, be aware that if the horn is 7' long, then it is 7' behind the horn's mount, that's serious time misalignement with your sub. You'll need to eirher put the horns forward by 7' or use a digital crossover to delay your sub.

[dkalsi]

The 2245 remains, in my opinion, a very good musical subwoofer.

I agree - I love the way it sounds in my DIY 4345.

I don't plan on using a bass-horn for the bass bin.

In my application, I would need whatever driver I decide on the play mid-bass and bass, in other words, it should be able to play all the way up to 200Hz.

I agree on your recommendation on the JBL 2245 as even JBL deemed it suitable to play up to 290hz in the 4345 Studio Monitor.

The only thing that bugs me about the 2245H is that they are NOT easy to find, and if you happen to find one - they sell at quite a premium.

[Lee in Montreal]

Whats great though with the 2245 is that 2245 and 2240 baskets are cheap. They usually trade for $35 to $45 while a JBL recone kit is around $250 if i am not mistaken (maybe higher these days). Therefore, for $300 you get a superb brand new subwoofer. That's a deal. A 2240h would give you a nice bass, but with a different caracter. Not as low, byt with more presence "where it counts" especially if your system on top won't go below 200Hz.

And beware of eBay sellers passing 2240s as 2245s. There are a lot of unscrupulous people on eBay...

[yggdrasil]

Whats great though with the 2245 is that 2245 and 2240 baskets are cheap. They usually trade for $35 to $45 while a JBL recone kit is around $250 if i am not mistaken (maybe higher these days). Therefore, for $300 you get a superb brand new subwoofer. That's a deal.
I completely agree.

I got a couple of working 2245's a few years back. They did sound good, but not in the same league as fresh recone's. Conclusion- get baskets and have them professionally reconed!

[dkalsi]

Conclusion- get baskets and have them professionally reconed!

That is exactly what I did when I built my DIY 4345 - and yes - I'm totally satisfied :)

[Mr. Widget]

I completely agree.

I got a couple of working 2245's a few years back. They did sound good, but not in the same league as fresh recone's. Conclusion- get baskets and have them professionally reconed!I think this is the best practice with all vintage JBLs when practical. Used drivers rarely are still up to spec... and we never know how hard a life they have lived. To buy a beautiful looking vintage driver at top dollar is always tempting but can easily be disappointing.


Widget

[ivica]

I completely agree.

I got a couple of working 2245's a few years back. They did sound good, but not in the same league as fresh recone's. Conclusion- get baskets and have them professionally reconed!

I have "feeling" that the original cones and the cones in the 2245 re-cone kits today are not the same quality.

reagrds
Ivica

[Mr. Widget]

I have "feeling" that the original cones and the cones in the 2245 re-cone kits today are not the same quality.

reagrds
IvicaI can't argue with a "feeling", but I doubt you are right. There have been a few iterations of the cone design, but I do believe they are all of the same quality. That particular driver has been built in the same plant in Mexico for a very long time now.


Widget

[dkalsi]

But I do believe they are all of the same quality.

Widget

I sure hope you are right as I may eventually go with the JBL 2245H. I love the way the sound - they just require one big box

[JeffW]

I have NOS 2245s and reconed in the last couple of years 2245s. I can't see the voice coils, but the cones look pretty much the same.

[Lee in Montreal]

I can't argue with a "feeling", but I doubt you are right. There have been a few iterations of the cone design, but I do believe they are all of the same quality. That particular driver has been built in the same plant in Mexico for a very long time now. Eaulive had a few problems with his Mexican 2225 cone kits about 18 months ago. I think he had two bad units out of four. JBL replaced them. Perhaps "Hecho in Mexico" happened earlier with the 2245 kits and now they have smoothened the production on them.

[frank23]

My 2 cents. I have used a pair of 2235 for years. I had them reconed by JBL, so have had them since "new". A few months ago I discovered the E145-8 and as far as music goes, I find them nicer than the 2235. The 2235 goes lower, but the E145 sounds faster (and yes I have read the articles that say that a bass can not sound fast) and times better with the 2123 I use.

[Mr. Widget]

A few months ago I discovered the E145-8 and as far as music goes, I find them nicer than the 2235. The 2235 goes lower, but the E145 sounds faster (and yes I have read the articles that say that a bass can not sound fast) and times better with the 2123 I use.:bouncy:

Agreed 100%!!!!


Widget

[ivica]

I can't argue with a "feeling", but I doubt you are right. There have been a few iterations of the cone design, but I do believe they are all of the same quality. That particular driver has been built in the same plant in Mexico for a very long time now.


Widget
Hi Mr.Widget,

When I say " a have a feeling", it is real, in the several points.

1. "Touch feeling"
I have an opportunity to to see (and touch by MY fingers) two 2445H drivers (taken out from some JBL old original boxes) and the cone seems very strong and thick. On the relatively new, (made in Mexico) "original" JBL recone kits ( C8R2245 ), the cone (touched by my fingers) seems fare less thick.

2. "Eyes feeling"
From the front side the cone ribs are almost near to the dust cap. On the recone kits the cone ribs are not so near the dust cap..
look at the:
http://www.audioheritage.org/vbulletin/showthread.php?8787-jbl-2245-H&p=236343&viewfull=1#post236343

Not to mention that the dust cap (on the recone kit) was dark almost black, while on the original is gray ("JBL gray")
(and seems much stronger and thicker if you 'knock on it' ).

3. "Listening feeling"
Listening a pair of 4345 ( 12 ft3) of boxes equipped with the original drivers vs re-coned (2245) , drivers have sounded different, what can be recognized instantly while playing some "drum" section of music. I can say may be the re-coned were deeper but more 'muddy', while with the original I could "see" (imagine) the size of the drum that was playing.

Interesting, almost the same results while comparing original 2231A and re-coned 2235H drivers (with JBL C8R2235 kits).

It would be interesting to compare some AF possibilities such as: MWA 2235 cone with their 1860 voice coils and Rick Cobb ( ebay: "looneytune2001") foam..........

Best Reagrads
ivica

[4313B]

JBL cones were made by Hawley back when it all mattered. Hawley died and JBL went on a safari to find a new vendor. After several fails they decided that Mogami could approximate the originals well enough and that is where we stand today.

With respect to the C8R2245H recone kit specifically, I have yet to run across a bad one from Mexico.

Nothing performs quite like a 2245H.


Interesting, almost the same results while comparing original 2231A and re-coned 2235H drivers (with JBL C8R2235 kits).The 2231A/H was seriously overdamped. It could handle a bit more DCR in the low pass coil(s) than the 2235H could. The 2235H sounded really nice hooked directly up to the driving amplifier (4355).

G.T. never cared for either of them. He speculated that "The fifteens were geometrically challenged." He said that he preferred the (aquaplased) LE14H and 2245H.


A few months ago I discovered the E145-8 and as far as music goes, I find them nicer than the 2235. The 2235 goes lower, but the E145 sounds faster (and yes I have read the articles that say that a bass can not sound fast) and times better with the 2123 I use.Well that's what makes DIY fun and JBL had a nice variety of fifteens available back then. Obviously an E145 wouldn't do in a Studio Monitor, hence the requirement for a 2231A/H or 2235H. And now a 2216Nd with EQ.

[dkalsi]

- Nothing performs quite like a 2245H.

- G.T. said that he preferred the (aquaplased) LE14H and 2245H.


I'm so glad to read the comments above. It seems to agree with the findings of fellow forum members here (per review of older posts).

Just to give a little more background on what it is I am trying to accomplish:

I will be using an Auzahorn (very similar to the one below but much larger) and matting it to Tang-Band 1808 driver. The Tang-Band has a reported sensitivity of 93db. It is my understanding that the horn will further increase the sensitivity (not of the driver itself but the combo together will have higher sensitivity).

Below the horn, I want to build a similar cabinet utilizing a what members here believe may be the most suitable driver.

My intentions are to use the bass bin from 30hz - 200hz. Many here agree that the 2245H may be a suitable driver for that application. I could use a 15" - 2235H, but I love/want more bass authority. I know the 2235H will go way above an beyond 200hz (and is often used up to 800hz), but the 200hz - 800hz holds no benefit for me.

I have another really dumb question.

It is my understanding that an 9 cuft enclosure may suffice for 30hz tuning - but in the event I have the real estate for 120 cubit foot enclosure, would tuning the 2245H for 25hz have any adverse impact its ability to play upto to 200hz.

In other words, with the exception of digging in deeper, would the sound from 50hz - 200hz change at all?

58406

[Ear4life]

Hey guys..

I don´t know if it´s the auqaplas it self, that does the difference. Or is it what it does to the cone...(weight and stiffens) that creates that extreme balanced speaker? Just keep in mind that many aftermarket kits for the 2245h is without aquaplas!! In other words you have to apply it your self. Other ways you will end up with a 2240 with foam suspension... Or what the 2234 is to the 2235. You will need to add the weight to bring fs down from about 30-32Hz to the desired 20Hz. I have seen many other examples of material to gain weight on a cone than aquaplas, but don´t know if the aquaplas it self has a sonic signature? :confused:

Regards
Martin

[Lee in Montreal]

@ Dkalsi - if you like bass with authority, definitely get the 2245h. It's musical, has grunt, and can shake the house. The 2235 is a small home woofer. I have both and feel it would take four 2235 to perform like a 2245. I myslef leaning toward a two-way 2245-based system too. I love my current 15" 2226 set-up, but definitely lack the bottom octave. And I am a bass addict. I have one single 2245 and therefore on the hunt for another before I build 12cft cabinets.

12cft tuned to 27Hz gets you a flat liner down to 30Hz and F3 at 27Hz. That'S without any boost or correction. On top it is almost flat up to 200Hz with an easy slop going up. you are down 3db at 300Hz.

The increase of volume will not impede response on top.

GO 2245 DaMn IT !!! ;-)

[IWC Doppel]

I have pretty much decided to use tow 4645c's with my horns from 22-100 Hz, these use 2242's, interested in any comparisons to 2245's of old, they seem a better option to the 2241's ?

[Lee in Montreal]

I have pretty much decided to use tow 4645c's with my horns from 22-100 Hz, these use 2242's, interested in any comparisons to 2245's of old, they seem a better option to the 2241's ? 2245 has Fs20Hz while the 2242 has Fs35Hz. They serve two different purposes. The 2242 is a great driver though. I would use them for parties. I am partial to the 2245 for music at home.

[spkrman57]

I preferred the 2242 which goes down almost as low as the 2245 but the 2242 has snap I don't get from the 2245.

Do you want deeper or more dynamic?

Ron

[Kalle]

I preferred the 2242 which goes down almost as low as the 2245 but the 2242 has snap I don't get from the 2245.

Do you want deeper or more dynamic?

Ron

What boxes did you use for your 2242`s?

Regards
Karl

[spkrman57]

What boxes did you use for your 2242`s?

Regards
Karl

9 cubic ft tuned to 28 Hz.

Boxes were built for Mike Baker(by 4313B) for his 2245's and then I got them and put 2242's in them.

Killer subs!!!

Ron

[Hans Bleeker]

I used to have 2 2245's in my living room, wel they lasted a week, to many neighbours started complaining, but they realy MADE low frequentie :) Im still with the 2235's , connected to an amp that DOESNT kill them, I use an QSC EX4000. is same as JBL MPX1200 but seems a Crown MA3500VZ or 5000VZ would do the trick also , hmmm better watch the volume :) The issue what I noticed with the 2235 is if connected to the wrong amp, power doesnt say a thing. the will sound VERY constrained. I used several high end amps on them, wel medium Hgh end , but they realy came to live when I connected them to a plain pro amp.
W15Gti, I love that speaker, its by no means as musical as a 2235, but it has brutal lows.
Im concider trying to run them nex to the 2235's and let them ony do to 100 Hz , same as in the 4435. Wonder how that would sound

[originaltubino]

9 cubic ft tuned to 28 Hz.Boxes were built for Mike Baker(by 4313B) for his 2245's and then I got them and put 2242's in them.Hey Ron, I'm going try a pair of the 4645B (8 cu. ft.) cabinets with 2242 in my basement setup. The spec sheet says it's tuned for 25Hz. Good starting place, right? Did you run yours with any EQ? What kind of low pass filter should I start with? Yeah, these are to use with Jensen Imperials, which still have the JBL LE15B. Haven't cracked the house foundation yet, so... MOAR BASS!

[maxwedge]

I have those cabinets with 2242's in them and used them for a DJ situation. Sounded fantastic for that but I prefer the 2245 for listening to music at home. The bass is much better with a single 2245. 2242 rolls of the bottom a lot quicker than the 2245 and are designed to be used in pro sound situations where you have a bunch of them grouped together, boosting the bottom. The 2245 would have too much bass in a pro sound application and sound muddy.

[Robh3606]

Hey Ron, I'm going try a pair of the 4645B (8 cu. ft.) cabinets with 2242 in my basement setup. The spec sheet says it's tuned for 25Hz. Good starting place, right? Did you run yours with any EQ? What kind of low pass filter should I start with? Yeah, these are to use with Jensen Imperials, which still have the JBL LE15B. Haven't cracked the house foundation yet, so... MOAR BASS!

EQ them at the tuning frequency add 6db Q2 just like the BX-63 don't forget to highpass filter them if used with EQ if you are going to push them hard.

Rob :)

[RMC]

maxwedge,

RE The 2245 would have too much bass in a pro sound application and sound muddy.

As part of the Concert Series JBL did released in 1986 a double 2245 VLF sound reinforcement cab, model 4842. Box tuning at 27 hz.

Richard

[DerekTheGreat]

+1 for the 2245H fire. I run two, and they are vastly superior to every other sub or low frequency driver I've auditioned, namely the 128H, 2214H. Very musical, ticks all the right boxes and massages your spine if called for. May or may not have cracked one of my windows. :D

[toddalin]

I like/use the 2241s. You can put them in a smaller cabinet than 2245s with more efficiency and they will go deeper than 2242s. I also prefer the sound of the accordion edge as opposed to the foam edge. I feel the accordion edge presents more harmonics and a more natural sound on bass guitar and especially string bass than the foam edge.

Most probably the cheapest to obtain too!

https://youtu.be/oLgQCHmXSUU

[maxwedge]

maxwedge, RE The 2245 would have too much bass in a pro sound application and sound muddy. As part of the Concert Series JBL did released in 1986 a double 2245 VLF sound reinforcement cab, model 4842. Box tuning at 27 hz. Richard Muddy isn't the word that I should have used. I like both the 2242 and 2245 but think that the 2242 is better in SR when multiple cabinets are used. The 2245 with a bunch of grouped cabs will have an elevated VLF where the same speakers using 2242 will be close to flat due to it's LF roll off because of LF coupling. Plus the 2242 is more efficient and handles more power. I mostly listen to rock and prefer the 2245 in my living room. I would probably do best with a 2242 in my left corner and a 2245 at the right side, which is a wall. :-)

[ivica]

Muddy isn't the word that I should have used. I like both the 2242 and 2245 but think that the 2242 is better in SR when multiple cabinets are used. The 2245 with a bunch of grouped cabs will have an elevated VLF where the same speakers using 2242 will be close to flat due to it's LF roll off because of LF coupling. Plus the 2242 is more efficient and handles more power. I mostly listen to rock and prefer the 2245 in my living room. I would probably do best with a 2242 in my left corner and a 2245 at the right side, which is a wall. :-)Hi maxwedgeAs I know 2242 is made for SR, and interestingly its TS parameters have a tendency to reach 2245 but measured under heavy load (large power)Regardsivica

[DerekTheGreat]

I like/use the 2241s. You can put them in a smaller cabinet than 2245s with more efficiency and they will go deeper than 2242s. I also prefer the sound of the accordion edge as opposed to the foam edge. I feel the accordion edge presents more harmonics and a more natural sound on bass guitar and especially string bass than the foam edge.

Most probably the cheapest to obtain too!

https://youtu.be/oLgQCHmXSUU

Hrmmm... How small a cabinet are we talkin' here? I think the B460 clone cabs I've got are 8cu ft like the originals? Increased efficiency is always nice. A quick look at the specs that make sense to me show the 2241 rated to 30hz vs the 2245 at 20hz. If I auditioned 2241's, would I still want/need the BX63A? Like Maxwedge said, I too, mostly listen to rock. Love the system for bass, have noticed how life-like bass guitar and drums sound now, very nice impact as well. So if it's possible to get that even better, I'm intrigued. There's a set of 2241H's on the bay for ~$500 + shipping.... EDIT: I see both "H" and "G" versions of the 2241. What's the "G" version and which is best for my application? - Oh, those are 4 ohm'ers.

[1audiohack]

Hey Derek;
If you try the 2241’s you will need more than the BX360A to get it to play as low as the 2245. Even more EQ in a smaller box.

As for efficiency there is actually a good automotive parallel here. You know by adjusting cam timing you can trade torque for horse power. With a woofer you can trade away LF response for a gain in efficiency. The 2241 has done just that. The natural frequency response will start later and tilt higher than the 2245.

Will you like it better? That is anyone’s guess.

All the best.
Barry.

[toddalin]

Hrmmm... How small a cabinet are we talkin' here? I think the B460 clone cabs I've got are 8cu ft like the originals? Increased efficiency is always nice. A quick look at the specs that make sense to me show the 2241 rated to 30hz vs the 2245 at 20hz. If I auditioned 2241's, would I still want/need the BX63A? Like Maxwedge said, I too, mostly listen to rock. Love the system for bass, have noticed how life-like bass guitar and drums sound now, very nice impact as well. So if it's possible to get that even better, I'm intrigued. There's a set of 2241H's on the bay for ~$500 + shipping.... EDIT: I see both "H" and "G" versions of the 2241. What's the "G" version and which is best for my application? - Oh, those are 4 ohm'ers.

You can run the 2241s down to ~6-1/2 cu ft interior volume with good results. (I thinks that's about what mine are.) For those who doubt the capability of the 2241 (especially if you do want to put them in big cabinets (up to 12 cu ft), run the 2241, 2242, and 2245 through WinISD and I think you will be suprised at the results. It's what convinced me.

[maxwedge]

You can run the 2241s down to ~6-1/2 cu ft interior volume with good results. (I thinks that's about what mine are.) For those who doubt the capability of the 2241 (especially if you do want to put them in big cabinets (up to 12 cu ft), run the 2241, 2242, and 2245 through WinISD and I think you will be suprised at the results. It's what convinced me. I'll run all of those in BBP6 at 12 cu ft and three 4 inch optimized ports tomorrow and post the graphs.

[maxwedge]

12 cu foot box and three 4 inch ports optimized for suggested FB for each driver. FB for each driver: 2241/30.66 Hz, 2242/26.28 Hz and 2245/22.11 Hz. http://i.imgur.com/N3EbE75.jpg (https://imgur.com/N3EbE75)

[RMC]

Scott,

RE "... for suggested FB for each driver." That and the shape of your curves leads me to believe you may have asked the software for max flat response or on its own it defaulted to max flat response?

This is generally not the best outcome in my experience. User done (playing with Vb and Fb) often generates a better result for me. Your curves also differ from those of JBL.

2241/2242: you're tuning the woofers below their 35 hz Fs, this can become a slippery road at high level, more so for 2242 Fb @ 26 hz. I know JBL did it in tech sheet, but will they put in writing they'll recone it free if its been damaged, claiming abuse (used outside of normal terms/capabilities)?

In addition note JBL's vented box for 2242 is 8 cu ft, not 10 cu ft as in 2241, a little marketing trick to make it look better bass wise. 12 cu ft makes it even more unreasonable in my view.

200 hz level higher than LF is a sign of a driver being stretched.

Richard

[maxwedge]

12 cu ft was used as suggested by post 41 and the extended bass option was used in the simulation. The FB was just what the program spit out and I wouldn't put a 2241 or 2242 in a box that big either.

[Ian Mackenzie]

I would look at it on the basis of where you want the box port frequency to produce the most output.

What is the goal?
Do you want very low sub bass output at the expense of higher bass output in the 35-50 region?
Do you want maximum visceral bass impact 35-50 hertz
Do you want maximum mid bass in a more compact enclosure 40-80 hertz

There are a few trade offs

On paper
1. The lower the box tuning (20-25 hertz) and the larger the enclosure (10-12 cu ft3)will produce lower maximum output from the port and woofer summed output at FB. This type of tuning will also have less maximum acoustic output in the 35-45 hertz region because the port output is much lower in the 20-25 region. If you want more low bass output look at multiple woofers and enclosures. (It’s subjective noticeably see below)

2. A somewhat less large enclosure volume (25% less than above ie 8-10 cuft3) with a higher port tuning frequency in the 28-36 hertz region will yield a system with significantly higher maximum acoustic output around the higher port tuning frequency. Consequently the maximum output below the port tuning frequency will diminish quickly. In practice this can be resolved with a high pass active frequency. For consumer applications this us generally not necessary. (This type of tuning is subjective most acceptable)

3. If maximum output as in a sound reinforcement application is an important look at the Xmax and peak excursion before damage of the driver for system reliability.

Maximally flat response, optimum volume or extended bass?
Some bass reflex enclosure simulators will offer preset tunings in these categories.

1. Maximally flat refers to the flattest system response in the pass band.
2. Optimum volume fits the closest response curve the high pass filter of tunings suggest
by the woofer TL parameters
3. Extended bass refers to a lower port tuning and a larger enclosure volume with a low
pass shelf curve in the response

Subjectively
Typically you will achieve a more visceral impact in option 2 with box tunings at 28-36 hertz and above with a somewhat smaller enclosure volume(8-10) This tuning will sound subjectively more dynamic than the same woofer with port tuning in the 20-25 region and larger enclosure 1.

The larger enclosure (10-12 cuft3) is more difficult to construct so that it is resonant free above 50 hertz. For this reason such large enclosure best limited to application below 80 hertz.

[1audiohack]

Scott,

… 2241/2242: you're tuning the woofers below their 35 hz Fs, this can become a slippery road at high level, more so for 2242 Fb @ 26 hz. I know JBL did it in tech sheet, but will they put in writing they'll recone it free if its been damaged, claiming abuse (used outside of normal terms/capabilities)? …

Richard

Tuning below Fs is not unusual or particularly dangerous.

JBL’s theater boxes 4642a and 4719?are tuned to 25Hz.

2242’s are pretty robust. I operated one slated for recone at 1800 Watts of low distortion 60Hz sine until I got tired of listening to it. That would be a direct connection to the 120V power grid. :)

Barry.

[Ian Mackenzie]

Tuning below Fs is not unusual or particularly dangerous.

I operated one slated for recone at 1800 Watts of low distortion 60Hz sine until I got tired of listening to it. That would be a direct connection to the 120V power grid. :)

Barry.

It’s been done already.

The Americans used isolated meeting chambers with multiple woofers humming at 60 hertz outside in the Cold War to keep secrets secret. But it didn’t stop counter espionage from within by Russian Moles.

[1audiohack]

It’s been done already…

Of course it has. The only thing new in the world it seems is the history you don’t know. Over and over, the ancients have stolen our secrets. :)

Barry.

[toddalin]

Based on the curves, as I have suggested, the 2241 gives the greatest "sense" of bass, even if it doesn't extend quite as low. Still, 32 Hz represents low C on the pedal board, and this is plenty low for what I listen to. Low E on a bass is ~40 Hz and the 2241 is all over the other varients at this frequency.

[RMC]

Hi Barry,

If my memory is correct many years ago Gene Czerwinski of Cerwin-Vega would go to trade shows and plug his Stroker woofer in 120V AC to show how robust it was. Have you stolen his "secret", lol.

That being said, downtuning puts more strain on a woofer. However nowadays with the larger excursion capabilities from woofers might explain that manufacturers are increasingly adventurous.

Ancestor 2240 had Fs 30hz and JBL modeled it in 10 cu ft but tuned it at 30hz, so at Fs not lower. The increased excursion capability of 2241 and 2242 probably lead JBL to be more daring in tuning these 5 hz below driver Fs in the spec sheets.

If you go from a B4 alignment to a B6, or straight for a B6, you down tune the box somewhat and then apply a boost/cut filter. The natural low end roll-off of the down tuned box, plus the cut filter, add to make an even steeper roll-off. My understanding is the 12 db/oct electrical cut filter has dual purpose: rolloff part of the Q = 2 boost near the filter's base on the VLF side, and at the same time mitigating some of the excursion strain put on the woofer using that same rolloff (two birds with one stone). So i'm a little skeptical that a sizeable downtuning with no filter would present little or no risk for a woofer at high drive. Wouldn't this mean the B6 cut filter has a single action only (rolling off part of the boost) and forget the rest like also helping decrease cone travel ?

2241 is a little different story than the others in the sense that its a high Qts driver, with these having more ability to naturally sustain (no EQ or filter) flat bass in a deeper bandwidth, than lower Qts units. Eargle has a couple of examples of this.

That Qts leading to a C4 standard alignment with some ripple in response (though it can be pretty small). A C4 is normally tuned lower than driver Fs for flat response, otherwise a response bump may appear (subject to cab size). The other two (2240 and 2242) will lead to Qb3 alignments or a derivative of this if the user models it his own way as i do.

In the traditional 18" SR woofer JBL went from 2240 Qts .23, to 2241 Qts .40 and then 2242 Qts .275 . So from low to high then back to somewhat low Qts respectively. (Btw back to high again with 2269 .36 !)

Hard to say exactly why this going back or so to an older "recipe" for 2242 but i may risk the following: high Qts woofers don't have as good transient response and likewise for their C4 alignments (Dickason and Eargle). In other words maybe users and sound contractors especially didn't recognized the 2240 sound in the 2241??

Finally, not everyone has the means to recone at will, i guess that's an incentive to keep a driver alive and well.

Richard

[RMC]

I previously posted this from Eargle's Loudspeaker Handbook, regarding cabs Fb shifts. Different application but the same downtuning principle and its impact (originally a Gander & Eargle AES paper).

[RMC]

Also i previously posted, from E-V's Pro Sound Facts, about step-down mode, essentially the same as downtuning initially. Having seen examples their slight reduction mentioned here is in the 2-3 db range. Applying a 3 db derating corresponds to half the power, so a 500W driver becomes a 250W unit. Besides E-V says if you need full power capacity from a woofer then don't step-down (downtune the cab).

[Ian Mackenzie]

One of the less considered woofer properties is linearity.

Linearity in the context of the cone area, Xmax and power compression defines linearity.

The 2245H can be tuned on paper to the same response of a 2235H.

The audibility of the 2245H is astonishing. It has more authority and impact. The larger driver also couples better to adjacent room boundaries.

Another consideration is that JBL measured the LF specs of systems using a passive low pass woofer crossover network. JBL took advantage of the benefits of the L1 dcr in the woofer filter to modify the total system LF response thus improving the voicing. The action of the DCR is to increase the total woofer QTS. By re tuning the enclosure volume and port frequency an improvement in LF extension while maintaining sensitivity can be obtained. Hoge has published documents on the subject. Gary Margolis former applications engineer at JBL also published some optimised LF tunings. Greg Timbers then implemented a Bessel tuning in the M9500 using staggered enclosure tunings.

In the DD67000 dual woofer system Greg Timbers originally designed the DD66000-67000 as a tri amp system. The additional inductor DCR of the low frequency passive crossovers benefits the LF extension and voicing of the passive system.

But in the tri amp mode the system sounded too lean so we added a 100 hz LF shelf filter with +4 db of boost. I don’t recall the specific +4 db frequency. Greg just knew what was required.

If you have a flexible dsp active crossover l would encourage experimenting with modest 0 - +4 LF boost at or above the port frequency and listen to the results with your system in your room. A subtle lift in the response below 100 hertz can really improve the overall balance of a system.

If using an 18 inch external self powered sub just dial in the level of the sub and listen. Measurements with REW will enable validation of your actual LF response including all the dips and peaks.

[short_circutz2]

Tuning below Fs is not unusual or particularly dangerous. JBL’s theater boxes 4642a and 4719?are tuned to 25Hz. 2242’s are pretty robust. I operated one slated for recone at 1800 Watts of low distortion 60Hz sine until I got tired of listening to it. That would be a direct connection to the 120V power grid. :) Barry.To attest to JBL being robust...Bit of background first...My father is from a very small community kind of in the middle of nowhere. Electronic parts were hard to get your hands on. Dad jad the first rock band in his community in the early 60s and was a JBL fan right from the start. He was using a normal edison type plug and socket to join his D130 loaded cab to his guitar head. Until someone "trying to be helpful" plugged the cord for the speaker cab into the wall outlet instead. 115v of 60Hz was all you could hear in the hall until dad made it to the stage to unplug it. That D130 not only surived the punishment, but dad went on to play many years thru that cabinet. To think that even a very much older 15 rated at a fraction of the power of the 2242 was also able to survive this just shows how robust JBL has always been.

[RMC]

short_circutz2,

On the other hand, in the most spectacular failure thread, both 2242 in your example were ripped and smoked!

This should remind people even the 2242 is not invincible to abuse. Hence my previous caution.

So you win some and you lose some...

Richard

[1audiohack]

Man has never made anything that man can’t break.

I earn my living trying to overcome the above.

Barry.

[Mr. Widget]

Man has never made anything that man can’t break.

I earn my living trying to overcome the above.

Barry.With emphasis on “earn”! :D

Widget

[RMC]

I wonder though if 2269 with huge excursion capability and power capacity might have survived such DJ abuse ? (assuming it existed at the time)

[DerekTheGreat]

:lurk: + :hyp:

[1audiohack]

Iv’e never tried to kill a 2269. My SUB18 has an ITECH 5000HD bridged driving it and it is just stupid how hard it plays.

I for fun should put a 2242 in that box and see how different it is. 2269’s are amazing.

Barry.

[Ian Mackenzie]

In actual use it depends on how the peak limiters are set up and any compressors.

Most high powered domestic powered subs have dynamic limiters and thermal limiters to minimise a failure.

Some modern pro power amps built in limiters.

https://jblpro.com/en-US/site_elements/2241h-data-sheet

http://warehousesound.com/r/jbl2242H.pdf

I’ve had a quick at the differences between the 2241 and the 2242.

On paper the 2242 has a higher spec.

But in a domestic diy user case the differences may not be that important.

The 2242 has a longer peak excursion limit before damage of 50mm versus 40mm in the 2241. But the 2242 needs a somewhat larger optimal enclosure of 10 cubic feet versus 8 cubic feet for the 2241. The 2241 appears to have a flatter midrange response and a better low frequency response than the 2242 ( un assisted). Noted the 2241 QTS is 0.40 which is considerably higher that the 2242 with a QTS of 0.28. This accounts for different low frequency performance.

The 2242 has a bit less power compression at full power.

For personal diy use the 2241 is potentially an easier driver to set up. If it were me l might consider a compound driver arrange in push pull offering the benefit of half the enclosure volume @4 cubic feet using dual drivers in parallel.

From memory the Clair Bros S4 compound system used 2 x 2241, 4 x E110, 2 x 2441 and 2 x 2405. Used in banks 4 or 8 systems a side front of house the S4 exhibited excellent low frequency reproduction to my ears.

[Ian Mackenzie]

A single 2241 with dual 2123, a 2250 on smith horn with 2405 would probably be a really cool diy project.

A bit of bass boost @ 32 hertz can usually bring a sense of balance in most situations because the woofer has the cone area and the displacement to make it happen.

[DerekTheGreat]

Hmm. How does a 2269 compare against a 2245? 2269 looks pretty rad, like one of those units you'd see multiples of stuffed in the trunk of car. I'm most concerned with accuracy and musicality though, not rattling all the fasteners out of my car or fillings from my teeth.

[1audiohack]

I haven’t had a 2245 on a proper box in my house in a long time. I broke a couple and moved on. That said, I think they are the most musical, if you can say that about a sub, of the three mentioned in this thread title.

That said, my SUB 18 is very musical and has some sonic signature that I don’t have good language to explain. It has this crazy energy that makes 20 Hz seem like a square wave. Not distorted like playing an impossible for a sub to recreate square wave, just clean hard energy.

Audio has very few words of its own, nearly all are borrowed and many of them are quite vague. Often I just don’t know how to describe what I hear and feel.

One other thing that is different about this set up is that I have never put as much power on one driver. 5000 Watts is a lot of headroom on a single driver.

Barry.

[DerekTheGreat]

Looks like I will be content with my 2245's. :)

[Ian Mackenzie]

http://warehousesound.com/r/jblTECHNOTE3-4.pdf

This pdf is a good read for those interested in the evolution of the 2242 through to the 2269 drivers.