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post #1 of 39 Old 04-19-2011, 10:49 AM - Thread Starter
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Hey guys,

I'm thinking through what I would like to couple with the SH50; I've entertained thoughts of both the LMS and B&C 21SW152 in sealed 5 cubes.

Instead of pursuing the ultiamte in single digit performance; I'm now considering best SQ down to 20Hz.

Anyone familiar with the JBL 2242H driver? I'm curious how the Model 5749 Low Frequency system would perform serving as a stand for the SH50. The 5749 is the Low Frequency bin for the 5742 Screen Array system.
http://www.jblpro.com/catalog/suppor...e=3&docid=1500

This is also the same driver utilized in the 4645C - although a single unit.
http://www.jblpro.com/catalog/suppor...pe=3&docid=626

Initially, I would power each cabinet with 1 channel from a Face Audio F1200TS.

I would appreciate feedback on experiences with the 2242H.

Larry
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post #2 of 39 Old 04-19-2011, 11:06 AM
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you are probably aware that the 2242h driver (with a slight mod coating) in a cab tuned to 25hz is the sub used by jbl in their cost-no-object reference systems, so there is some reason to believe you are barking up the right tree.

ae speakers has the td18h+ which may be better then the 2242h in some respects. it is on sale right now. another option is the electrovoice evx180b.

anyone in cabs tuned to 20hz 8-9cubic feet and high passed will provide very good bass.

a good approach is to make sure that you can hit your spl requirements up high, then based on your budget keep adding speakers and amps until you are flat to unity.

a rough rule of thumb is that it takes two drives and twice the power to equal a ported (but the ported will require more than twice the space).

"I would appreciate feedback on experiences with the 2242H."

the only way to describe it is both delicate the thunderous.

it isn't the most popular choice around here, but over at the audioheritage.com site, the comments are universally positive.

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post #3 of 39 Old 04-19-2011, 11:15 AM
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Are you planning to use them on a LFE channel or on the L/C/R channels? I wouldn't suggest limiting your placement by using them as stands unless you plan to have additional bass sources such as a sub on the LFE.
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post #4 of 39 Old 04-19-2011, 11:29 AM
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that is good advice there. bass bins will interact with your room. sometimes in non-intuitive ways. keep them separate from your mains and you'll be good. the harman paper on this is a good one.

http://www.harman.com/EN-US/OurCompa...s/multsubs.pdf

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post #5 of 39 Old 04-19-2011, 11:54 AM
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Concerning the 2242H, it is a top notch driver, although I haven't heard it. I have heard its older version the 2245H and I love it. The 2242H is more efficient and handles more power, but has a higher Fs.

The problem is that the 2242H is ~$650 whereas the TD18H is $400 and you can get the B&C 21's for around $500. If you are only playing down to 20hz, I'd probably choose the TD18H.

Another option would be two woofers in a PPSL configuration. Someone posted a pic of it Penn's midbass horn thread. The configuration purports to significantly reduce distortion especially in lower frequencies where shorting rings become less effective. It is something I plan to try at some point, but I haven't had the chance. You could use two AE AV15Hs per box in this config and you could even do it sealed with a L/T circuit. This avoids port noise, port resonances and backwave reflections. You might even be able to run some of the other subs you mentioned sealed with EQ.
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post #6 of 39 Old 04-19-2011, 12:29 PM
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"although I haven't heard it"

if you have been to a good movie theater, you have probably heard it. ;-)

"Someone posted a pic of it Penn's midbass horn thread."

that might have been me. ;-)

good advice overall...av15's are not available currently as i understand it.

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post #7 of 39 Old 04-19-2011, 01:14 PM - Thread Starter
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Wonderful feedback gentlemen; thank you very much.

I can get the 2242H for $469.44 each.

My initial thought was to use the 5749 as a stand, and to also serve duty on the LFE channel; not as the base bin for LCR.

The thought would be 3 5749 cabinets in the front of the room, and perhaps a pair of the 4645C for the rear corners. The 4645C could be moved along the rear and/or side walls to even-out response.

I'm merely thinking through options here and may yet go with the B&C, but I've heard a lot of positive things about the JBL drivers.

Thanks for the suggestions.

Larry
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post #8 of 39 Old 04-19-2011, 05:21 PM
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I own a 2242h driver that is mounted in a 4.5 cu ft ported enclosure. Nearfield measurements show that it rolls off at 30 Hz. I love the way it sounds, very musical. It has a very tight sound that is not bloated. I will eventually put it in a 12 cu ft box tuned to 22Hz just to try. These drivers will not play much below 20Hz and that is why they are not popular on AVS Forums.

It seems that most around here care about: 1) xmax, 2) flat response to at least 16Hz, and 3) power handling.

I have compared it directly to my LLT 18" Avalanche - no comparison. Down low the Ava kills it but up high the JBL is leaps and bounds above it (both in sound quality, punch...tightness...how ever you want to describe it).

I have also compared it to my 18" Mach 5 Audio MJ-18 sub. It is mounted in a very similar sized enclosure that is nominally tuned to the same frequency as the JBL. I have done A/B testing in the same room between the two. The JBL sounds better to me. It is more musical and tracks the source a lot better. The Mach 5 has a fatter sound to it, bloated if you will.

I would love to compare my JBL to the LMS 5400. Obviously, down low the LMS would kill it but up high my bets are on the JBL (IMO).
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post #9 of 39 Old 04-19-2011, 05:24 PM
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Forgot to mention, also take a look at the JBL 2245h. It models nicely and is known for great sound quality.
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post #10 of 39 Old 04-19-2011, 05:41 PM - Thread Starter
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Hi nichol1997,

Thanks for your input here. I have not read a negative comment to date regarding the 2242h; the problem is finding those rare folks like yourself who have heard the 2242h as well as some of the typical drivers implemented in the HT environment.

I think I'm going to pick up a 4645C and play around with it; this unit is a 2242h in 8 cubes tuned to 25Hz. I know these drivers rolloff sharply below tune (would require a hpf at ~20Hz), but I would think multiples would be solid to 20Hz in-room.

Larry

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Originally Posted by nichol1997 View Post

I own a 2242h driver that is mounted in a 4.5 cu ft ported enclosure. Nearfield measurements show that it rolls off at 30 Hz. I love the way it sounds, very musical. It has a very tight sound that is not bloated. I will eventually put it in a 12 cu ft box tuned to 22Hz just to try. These drivers will not play much below 20Hz and that is why they are not popular on AVS Forums.

It seems that most around here care about: 1) xmax, 2) flat response to at least 16Hz, and 3) power handling.

I have compared it directly to my LLT 18" Avalanche - no comparison. Down low the Ava kills it but up high the JBL is leaps and bounds above it (both in sound quality, punch...tightness...how ever you want to describe it).

I have also compared it to my 18" Mach 5 Audio MJ-18 sub. It is mounted in a very similar sized enclosure that is nominally tuned to the same frequency as the JBL. I have done A/B testing in the same room between the two. The JBL sounds better to me. It is more musical and tracks the source a lot better. The Mach 5 has a fatter sound to it, bloated if you will.

I would love to compare my JBL to the LMS 5400. Obviously, down low the LMS would kill it but up high my bets are on the JBL (IMO).

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post #11 of 39 Old 04-19-2011, 05:50 PM
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I think you may miss the sealed sound and having all of the content below your new tuning point.

Good luck though. I went from sealed, to high sensitivity horns, back to sealed. I think MKTheater did the same, however he goes through gear faster than anyone.
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post #12 of 39 Old 04-19-2011, 06:11 PM - Thread Starter
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Deep down I know you are likely correct notnyt; I merely have an itch to try something different, and since I currently have NO subs, I'm fumbling around in the dark. Ultimately I will likely stick with my original plan of multiple sealed 21SW152s.

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Originally Posted by notnyt View Post

I think you may miss the sealed sound and having all of the content below your new tuning point.

Good luck though. I went from sealed, to high sensitivity horns, back to sealed. I think MKTheater did the same, however he goes through gear faster than anyone.

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post #13 of 39 Old 04-19-2011, 06:48 PM
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If you went with multiple 21SW152's those can be run sealed with EQ to bring up the bottom end. The 2242 wouldn't do as well in sealed because it will be down on both Sd and Xmax. Both would do very well ported. I mention that because it will give you options if you want to try sealed vs ported.

John J at AE claims his TD18H has no peer. I'd be very keen on trying those for this purpose.
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post #14 of 39 Old 04-19-2011, 09:26 PM
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TD18 is a very appealing driver, but in my sims I've found it appears to be designed for a reasonably sized cab and 40 Hz extension. For a pro woofer setup it appears to be the one to beat. However, it does suggest a different bass approach. I'd be inclined to use it as a stereo active woofer down to 40 Hz to take care of the music side of things, and cross higher than you would with a sub. Then you fill in the bottom end with a single monster sub, even if you have multiple drivers clustered. Subs will generally sum together more efficiently when closely clustered and used in this way. Two identical subs spaced apart may only add together with 3db increase vs 6db when put together. Also with this arrangement, you then put the clustered subs in a location for maximum gain below 40 Hz and in terms of powering them, they will see a lower duty cycle.

So here you have two options. One is to take some sub drivers and run them up to say 80 Hz in a LFE arrangement. Another is to run active woofers combined with a single monster sub cluster. The woofers will probably run on more moderate power, 400w with pro 18s will exceed 120 db.
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post #15 of 39 Old 04-20-2011, 07:16 AM
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Quote:
Originally Posted by nichol1997 View Post

I own a 2242h driver that is mounted in a 4.5 cu ft ported enclosure. Nearfield measurements show that it rolls off at 30 Hz. I love the way it sounds, very musical. It has a very tight sound that is not bloated. I will eventually put it in a 12 cu ft box tuned to 22Hz just to try. These drivers will not play much below 20Hz and that is why they are not popular on AVS Forums.

It seems that most around here care about: 1) xmax, 2) flat response to at least 16Hz, and 3) power handling.

You forgot to mention its > $650 for a pro audio woofer that is not meant for HT low frequency. Very few build full range main speaker designs either. There are better choices for a fraction of its price tag like the AV series woofers that are real subwoofers that can actually perform past 200Hz too.

We do focus on HT performance more and not 2 channel audio (that is why I love this forum better then others) and that requires your two points above. Although there is no reason in my mind why people can not have both. Get the right subwoofer designs then get the righ full range main designs. To me this thread is about full range mains and really should not have any discussion about subwoofer response in room because that topic requires a different design.



Quote:


I have compared it directly to my LLT 18" Avalanche - no comparison. Down low the Ava kills it but up high the JBL is leaps and bounds above it (both in sound quality, punch...tightness...how ever you want to describe it).

I have also compared it to my 18" Mach 5 Audio MJ-18 sub. It is mounted in a very similar sized enclosure that is nominally tuned to the same frequency as the JBL. I have done A/B testing in the same room between the two. The JBL sounds better to me. It is more musical and tracks the source a lot better. The Mach 5 has a fatter sound to it, bloated if you will.

I would love to compare my JBL to the LMS 5400. Obviously, down low the LMS would kill it but up high my bets are on the JBL (IMO).

Its an apples vs orange type comparisons. Of course the JBL will sound better then the MJ-18s since the MJ-18s are a fraction of the JBLs price and they are meant for low end frequencies only. The JBL is designed as a music woofer that extends up pretty high. Not a good comparison IMO. Even the LMS5400 is not a good comparison vs the JBL....completely different drivers meant for different operation.

If I had the JBL 2242 (I still might swap the JBL 2226s for them!!) I would build the JBL 2240 60Hz mid bass horn from here.... http://www.inlowsound.com/

Read some of the other discussion recently about smoothing the response from 100Hz to 300Hz has me also thinking about flanking mid bass designs but I have not figure that one out.

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post #16 of 39 Old 04-20-2011, 10:55 AM - Thread Starter
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I apologize for not being more clear in my inquiry. Having SH50 in the system I'm assuming I'll have 80Hz and up covered nicely. I'm looking for the best SQ between 20Hz - 80Hz, and I'm not 'immediately' concerned with < 20Hz capability.

With my previous system (6 sealed Mal-X) I experienced < 20Hz content and do agree it adds considerably to the overall HT experience. I had the previous system for a couple years, and I'm merely looking to try something different.

The 20Hz - 80Hz range led me to consider the 2242H as in room I would expect decent extension to 20Hz with multiples. I can get these drivers for < $450ea.

Larry

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You forgot to mention its > $650 for a pro audio woofer that is not meant for HT low frequency. Very few build full range main speaker designs either. There are better choices for a fraction of its price tag like the AV series woofers that are real subwoofers that can actually perform past 200Hz too.

We do focus on HT performance more and not 2 channel audio (that is why I love this forum better then others) and that requires your two points above. Although there is no reason in my mind why people can not have both. Get the right subwoofer designs then get the righ full range main designs. To me this thread is about full range mains and really should not have any discussion about subwoofer response in room because that topic requires a different design.





Its an apples vs orange type comparisons. Of course the JBL will sound better then the MJ-18s since the MJ-18s are a fraction of the JBLs price and they are meant for low end frequencies only. The JBL is designed as a music woofer that extends up pretty high. Not a good comparison IMO. Even the LMS5400 is not a good comparison vs the JBL....completely different drivers meant for different operation.

If I had the JBL 2242 (I still might swap the JBL 2226s for them!!) I would build the JBL 2240 60Hz mid bass horn from here.... http://www.inlowsound.com/

Read some of the other discussion recently about smoothing the response from 100Hz to 300Hz has me also thinking about flanking mid bass designs but I have not figure that one out.

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post #17 of 39 Old 04-20-2011, 11:00 AM
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Quote:
Originally Posted by 04FLHRCI View Post

I apologize for not being more clear in my inquiry. Having SH50 in the system I'm assuming I'll have 80Hz and up covered nicely. I'm looking for the best SQ between 20Hz - 80Hz, and I'm not 'immediately' concerned with < 20Hz capability.

With my previous system (6 sealed Mal-X) I experienced < 20Hz content and do agree it adds considerably to the overall HT experience. I had the previous system for a couple years, and I'm merely looking to try something different.

The 20Hz - 80Hz range led me to consider the 2242H as in room I would expect decent extension to 20Hz with multiples. I can get these drivers for < $450ea.

Larry

yeah, sorry I know your requirements and Im not questioning them. I was trying to point out that sometimes it becomes apples vs orange when trying to compare drivers. Others are posting why no one picks this JBL driver and there is more too it then the points raised.

Great price. In another thread it was posted that the TD18H is on sale for under $400. Now that would be a good comparison, from my POV the TD series is as good as anything JBL creates.

IMO, you can not go wrong with either. It will be a serious 20Hz to 20KHz setup!!


How about that JBL in some sort of bass horn to match the SH-50??

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post #18 of 39 Old 04-20-2011, 11:10 AM - Thread Starter
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penngray,

You have my interest in a bass horn implementation; I'll hit audioheritage and lean heavily on the search button

Regards,

Larry

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yeah, sorry I know your requirements and Im not questioning them. I was trying to point out that sometimes it becomes apples vs orange when trying to compare drivers. Others are posting why no one picks this JBL driver and there is more too it then the points raised.

Great price. In another thread it was posted that the TD18H is on sale for under $400. Now that would be a good comparison, from my POV the TD series is as good as anything JBL creates.

IMO, you can not go wrong with either. It will be a serious 20Hz to 20KHz setup!!


How about that JBL in some sort of bass horn to match the SH-50??

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post #19 of 39 Old 04-20-2011, 11:21 AM
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For awhile I have been wondering if direct radiating designs are miss match for horn solutions.

My outstanding question....If we have horn main speakers then should we have horn bass designs??

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post #20 of 39 Old 04-20-2011, 11:27 AM
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Quote:
Originally Posted by penngray View Post



For awhile I have been wondering if direct radiating designs are miss match for horn solutions.

My outstanding question....If we have horn main speakers then should we have horn bass designs??

Not necessary IMHO!

I would let the SH-50's go as low as possible and just cross them over to the Mal-x sealed system for the full bandwidth. I would never stop at 20hz. I bet in room the SH-50's would go down to close to 30-40hz with authority so the multiple Malx would do the rest. I don't think there is a need for changing anything.

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post #21 of 39 Old 04-20-2011, 11:34 AM
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Quote:
Originally Posted by MKtheater View Post

Not necessary IMHO!

I would let the SH-50's go as low as possible and just cross them over to the Mal-x sealed system for the full bandwidth. I would never stop at 20hz. I bet in room the SH-50's would go down to close to 30-40hz with authority so the multiple Malx would do the rest. I don't think there is a need for changing anything.

I have to disagree, knowing that the SH-50s do not remotely go to 30Hz. I would say that for max SQ you should never run main speakers near their F3 point because the distortion is too high compared to subs and also the XO point will have a bad curve when its close to the F3 point. If the F3 is 50Hz then a 70Hz XO point is usually a good starting point. If I cared about low frequency response I would XO them above 400Hz!! They have a nasty dips!

I also still have a question about direct radiating mixing with horn designs and Im curious about the differences with 100% horn solutions vs mixed solutions.

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post #22 of 39 Old 04-20-2011, 12:24 PM
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Quote:
Originally Posted by penngray View Post

I have to disagree, knowing that the SH-50s do not remotely go to 30Hz. I would say that for max SQ you should never run main speakers near their F3 point because the distortion is too high compared to subs and also the XO point will have a bad curve when its close to the F3 point. If the F3 is 50Hz then a 70Hz XO point is usually a good starting point. If I cared about low frequency response I would XO them above 400Hz!! They have a nasty dips!

I also still have a question about direct radiating mixing with horn designs and Im curious about the differences with 100% horn solutions vs mixed solutions.

Well, we have to wait and see how the SH-50's measure in room and at what distortion. It is very easy integrating horn speakers with sealed subs but it was very hard for me to integrate my dts-10 with my horn speakers. Very possible but I don't think it being all horn loaded matters as much.

The SH-50's go down to 50hz with authority outside so Danley says. In room who knows. I don't think the mal-x at 50hz and under(6 drivers) would do bad from 50hz and down to 20hz compared to the jbl's, not 20-50hz anyways, above that, JBL's rule but now the danley's are kicking in.

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post #23 of 39 Old 04-20-2011, 01:17 PM
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In room, the response won't extend much on the SH50s. They will still be around 50hz, maybe a couple ticks lower, but not much.

I can't say definitively, but if I had to guess, I don't think using a midbass horn vs a high efficiency direct radiator would be a very large improvement. The main advantage is cost (cheaper driver and less power) but I find it interesting that JBL does their cinema bass with simple ported enclosures and very high performance drivers instead of horns. A driver like the 2242H will give you just a little less efficiency, but still quite high. In a home, it still won't need much power

Anyway, if your receiver allows it, I'd run your speakers as LFE+mains and let the SH50s run wide open. Then put your subs on the LFE channel crossed at 120hz and move them around your room until you get the best response. The good thing is that any of your choices (21SW152, 2242H or TD18H) will sound great up to 120hz.

I would still look into using them in a PPSL config. I hypothesize that the real advantage to that config isn't so much the distortion cancellation of running them inverted to each other as it is the manifold providing an acoustic low pass filter in the 150-300hz range. It will filter the harmonic distortion similar to a bandpass sub but without being a bandpass sub. Can you swing 4 of drivers for two PPSL boxes?
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post #24 of 39 Old 04-20-2011, 02:18 PM
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Quote:
Originally Posted by MKtheater View Post

Well, we have to wait and see how the SH-50's measure in room and at what distortion. It is very easy integrating horn speakers with sealed subs but it was very hard for me to integrate my dts-10 with my horn speakers. Very possible but I don't think it being all horn loaded matters as much.

That not really an answer, its just anecdotal. We need theory and measured comparisons to really get into what is truely a better match. I also kept telling you about your mains F3 point vs the DTS-10 max range (50Hz). It was always a mismatch.

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The SH-50's go down to 50hz with authority outside so Danley says. In room who knows. I don't think the mal-x at 50hz and under(6 drivers) would do bad from 50hz and down to 20hz compared to the jbl's, not 20-50hz anyways, above that, JBL's rule but now the danley's are kicking in.

Rooms really do not have gain up that high so the measured response is the in room response. Again, you do not XO a main speaker at its F3 point that is just not a good design approach.

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post #25 of 39 Old 04-20-2011, 02:20 PM
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Originally Posted by coctostan View Post

In room, the response won't extend much on the SH50s. They will still be around 50hz, maybe a couple ticks lower, but not much.

I can't say definitively, but if I had to guess, I don't think using a midbass horn vs a high efficiency direct radiator would be a very large improvement. The main advantage is cost (cheaper driver and less power) but I find it interesting that JBL does their cinema bass with simple ported enclosures and very high performance drivers instead of horns. A driver like the 2242H will give you just a little less efficiency, but still quite high. In a home, it still won't need much power

I wonder if its more of a size issue. Its hard to sell large horn designs, the logistics behind shipping, installing them too would be a nightmare in the pro audio world. Ported enclosures are easy to build and sell.

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post #26 of 39 Old 04-20-2011, 02:45 PM
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I always cross at 80hz. The dts-10 played midbass very well in one location that did not fit anymore so I switched back to sealed.

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post #27 of 39 Old 04-20-2011, 03:40 PM - Thread Starter
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Yes, sir.

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Originally Posted by coctostan View Post

Can you swing 4 of drivers for two PPSL boxes?

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post #28 of 39 Old 04-20-2011, 05:36 PM
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Originally Posted by penngray View Post

I wonder if its more of a size issue. Its hard to sell large horn designs, the logistics behind shipping, installing them too would be a nightmare in the pro audio world. Ported enclosures are easy to build and sell.

It could be, but I don't think size is much of an issue for the cinema line. Look at the huge four driver midhorns. They also don't care about weight. I'm sure JBL could do a few things to squeeze a tiny amount of performance out of their setups but it obviously doesn't make sense to them. The cinema line is pretty much 100% performance oriented. Klipsch does still use horns for bass and obviously Danley does too. Outside of that, most of the commercial Cinema guys use direct radiators for their bass (JBL, QSC, EAW, etc).

The main advantage I see for a bass horn is the acoustic low pass filter inherent in the design. IMO, this is the biggest advantage to front baffle mounted bass speakers, at least in a one-off home setting.

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Yes, sir.

If you want an ultimate performer, I'd go with 4 of any of those drivers in 2 PPSL boxes. Build them with a slot port that you can plug and convert to sealed if you feel like trying them in sealed with eq. Any of these subs will perform well down low sealed with EQ. The 21SW152 will do the best because it will have far more displacement than the other two. It is likely marginally weaker in the SQ department but I would take that tradeoff for the flexibility.

If you give me some general footprint dimensions I can make a quick sketchup model to see if a PPSL will work.

I don't think you can underestimate the advantage of the acoustic low pass filtering effect. Without the acoustic low pass, when a 80hz tone is played, upper harmonics are also present, unfiltered. It doesn't matter if the electronic crossover is set to 120hz, you will produce harmonic distortion well above that. IMO, that is why people say they can localize bass up to 120hz. They are really localizing the harmonics. This is why Geddes uses bandpass designs in his multisub subs. They are placed around the room playing up to 120hz and you can't localize them because the harmonic distortions are filtered. The PPSL would work similarly but with greater extension.

I'd guess you don't see them often commercially because it is just cheaper and easier to use one better driver. It is much easier to mass produce a box without a manifold. For a DIYer it isn't a big deal and you are already using top of the line drivers.
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post #29 of 39 Old 04-20-2011, 06:13 PM
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Originally Posted by penngray View Post

You forgot to mention its > $650 for a pro audio woofer that is not meant for HT low frequency. Very few build full range main speaker designs either. There are better choices for a fraction of its price tag like the AV series woofers that are real subwoofers that can actually perform past 200Hz too.

We do focus on HT performance more and not 2 channel audio (that is why I love this forum better then others) and that requires your two points above. Although there is no reason in my mind why people can not have both. Get the right subwoofer designs then get the righ full range main designs. To me this thread is about full range mains and really should not have any discussion about subwoofer response in room because that topic requires a different design.





Its an apples vs orange type comparisons. Of course the JBL will sound better then the MJ-18s since the MJ-18s are a fraction of the JBLs price and they are meant for low end frequencies only. The JBL is designed as a music woofer that extends up pretty high. Not a good comparison IMO. Even the LMS5400 is not a good comparison vs the JBL....completely different drivers meant for different operation.

If I had the JBL 2242 (I still might swap the JBL 2226s for them!!) I would build the JBL 2240 60Hz mid bass horn from here.... http://www.inlowsound.com/

Read some of the other discussion recently about smoothing the response from 100Hz to 300Hz has me also thinking about flanking mid bass designs but I have not figure that one out.

Your points are noted and understood.

The OP mentioned two pro-drivers and the LMS (I assumed he was talking about LMS 5400). I then offered my opinions and listening impressions between a pro-driver and high-excursion drivers.
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post #30 of 39 Old 04-20-2011, 07:01 PM - Thread Starter
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nichol1997,

Just wanted to let you know I did value your input to this thread.

Regards,

Larry

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Your points are noted and understood.

The OP mentioned two pro-drivers and the LMS (I assumed he was talking about LMS 5400). I then offered my opinions and listening impressions between a pro-driver and high-excursion drivers.

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