Anyone using partial/full B&C IPAL solution? - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 58 Old 12-08-2019, 12:24 PM - Thread Starter
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Anyone using partial/full B&C IPAL solution?

Hey comunity.
I'm thinking about that, for compact universal bass solution. Not sure about certain technical details. I would guess only actual users could tell. Anybody around? Thank you in advance:
Pressure probe usage for two speakers in two bins, safety if one speaker goes unconnected, speaker design and so on...
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post #2 of 58 Old 12-08-2019, 12:40 PM
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Quote:
Originally Posted by Petr Berka View Post
Hey comunity.
I'm thinking about that, for compact universal bass solution. Not sure about certain technical details. I would guess only actual users could tell. Anybody around? Thank you in advance:
Pressure probe usage for two speakers in two bins, safety if one speaker goes unconnected, speaker design and so on...


Very few people here have used the IPAL, due to price and amplifier difficulties with the 1ohm load.

I don’t know of anyone who has used the powersoft IPAL modules with them, some have had good luck running them with speakerpower amps.

Ricci designed the SKHorn for a pair of 21” IPALS, and it works well.

http://data-bass.ipbhost.com/topic/6...bwoofer-files/

Chris
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post #3 of 58 Old 12-08-2019, 12:51 PM - Thread Starter
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Hello. Thanks. That's why I'm thinking about full IPAL solution. To not worry about loading and amps. But those 18“s should be driven relatively easily. In my design for "PA" usage, the impedance would be quite high, that many conventional amps would be able to drive these. I'm mostly afraid of the fact that these drivers have only 15mm of Xvar marked on these. I guess these drivers get less than ideal regarding linearity in high cone excursions, and only IPAL DSP and amp can possibly fight that effectively. I also wonder about some mentined reliability issues. I would like to know if newer pieces have leads integrated in the spider, or if these still lead through the air. I guess I need to find out myself, but will be thankful for any info I get...
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post #4 of 58 Old 12-08-2019, 01:58 PM
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Tom over at PSA is using both the 18" and 21" IPALs in his newest dual woofer units.

Theater: JVC RS540U, 2.35:1 142" screen, Onkyo RZ1100, Panasonic UB820, Outlaw Audio M2200 Monoblock x3, Klipsch RF7II, RC64II, RS62II, 5800CII x4 Atmos, PSA V3611 Subwoofer x2.
2 Channel: Parasound P6, Parasound A23+, Rega Planar 6 with Ortofon 2M Bronze, Klispch La Scala II, Behringer NX6000D, B&C 21DS115-4 powered Devastator V1 x2.
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post #5 of 58 Old 12-08-2019, 09:23 PM
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Eminence has an IPal competitor that is 6ohm nominal.


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post #6 of 58 Old 12-09-2019, 01:57 AM - Thread Starter
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I'm rocking two 21DS115s, and I'm looking on 18IPALs to downsize. Those 21s are awesome (including Eminence) but that is not the way for me.. Thanks.
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post #7 of 58 Old 12-09-2019, 07:31 AM
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They have 18’s too, which is why I mentioned them...


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post #8 of 58 Old 12-09-2019, 07:55 AM
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Anyone using partial/full B&C IPAL solution?

Quote:
Originally Posted by Trimlock View Post
They have 18’s too, which is why I mentioned them...


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The specs for the eminence tour grade 18’s aren’t super impressive. The b&c 18ds looks better for less money.
The 18ipal does look good. The BMS 18n862 should be pretty competitive also.

Chris
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post #9 of 58 Old 12-09-2019, 08:15 AM - Thread Starter
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Trimlock: Didn't know that, thanks. After closer look, it seems the Eminence is no match for 18DS115 and 18IPAL. I like how both Eminence and BMS have long stroke, but in my application I'm not excursion limited. At least not for PA usage. For home usage, sure, gimme more displacement volume...

I have read some info about IPAL solution on data-bass, and it seems it's not all honey and happy usage. The amp is hot and noisy, it is quirky to use, it has been "downgraded" regarding software settings and maximum output, sooo I might be looking the wrong direction after all. Or maybe just the driver. After hearing about some reliability issues, I wonder if they switched to in-spider leads on IPAL too...
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post #10 of 58 Old 12-09-2019, 09:39 AM
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Quote:
Originally Posted by Petr Berka View Post
Trimlock: Didn't know that, thanks. After closer look, it seems the Eminence is no match for 18DS115 and 18IPAL. I like how both Eminence and BMS have long stroke, but in my application I'm not excursion limited. At least not for PA usage. For home usage, sure, gimme more displacement volume...

I have read some info about IPAL solution on data-bass, and it seems it's not all honey and happy usage. The amp is hot and noisy, it is quirky to use, it has been "downgraded" regarding software settings and maximum output, sooo I might be looking the wrong direction after all. Or maybe just the driver. After hearing about some reliability issues, I wonder if they switched to in-spider leads on IPAL too...


If you’re looking at the 18’s, they can run on many standard amps being a 2ohm nominal. The 21 is the challenging one to drive without the IPAL amp.

Not sure about reliability on the IPAL.
I’ve flogged my 18ds past where they should be pushed on 2500w and no issues. Home usage though, not sine wave music for long duration.

Chris
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post #11 of 58 Old 12-09-2019, 10:09 AM - Thread Starter
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Yes, I'm looking just on 18IPALs to not downgrade much from 21DS115. At the moment, I feed these with upgraded T. AMPs TA-2400 MK-X, which give around 2700W peak, 2400W burst, and 1800W RMS... Did not have a reason to clip them or run them hot, but the dynamics is put to use... These would need to be changed too, as these are not suited for 2Ohm usage. That was the reason I was thinking about native solution with IPALMODs, but the more I read about these, the less they seem to suit home environment. I would rather stay with lovely 21DS115s unless I'm sure the other solution is better... No hurry.
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post #12 of 58 Old 12-09-2019, 10:44 AM
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Quote:
Originally Posted by Petr Berka View Post
Yes, I'm looking just on 18IPALs to not downgrade much from 21DS115. At the moment, I feed these with upgraded T. AMPs TA-2400 MK-X, which give around 2700W peak, 2400W burst, and 1800W RMS... Did not have a reason to clip them or run them hot, but the dynamics is put to use... These would need to be changed too, as these are not suited for 2Ohm usage. That was the reason I was thinking about native solution with IPALMODs, but the more I read about these, the less they seem to suit home environment. I would rather stay with lovely 21DS115s unless I'm sure the other solution is better... No hurry.

Not exactly sure what you’re trying to change. Just looking for a smaller box to move?
If so, and you’re not using the full displacement potential of the 21ds, just go to 18ds on your current amps. Looks like the only advantage of the 18IPAL is more displacement.


Chris
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post #13 of 58 Old 12-09-2019, 11:46 AM - Thread Starter
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Yes, striving for most "power output" density, or SPL/bandwidth/box size ratio.
For home usage, I actually use about full excursion capabilities of the driver, as I can afford to EQ the box heavily under the port tuning. While for PA, the box is tuned low, so the cone excursion at about 50Hz is also little higher than normal. I'm perfectly fine with 21DS, it's just I wanted something top notch and buy myself something awesome for rewards, and being able to move these boxes. The more they're movable, the more often I take them out. 18IPALs seem to hold its own against DS, losing about 0.5-1db on average compared to 21DS. That seems to be fair trade for more fun outside.
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post #14 of 58 Old 12-09-2019, 05:38 PM
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Quote:
Originally Posted by a77cj7 View Post
The specs for the eminence tour grade 18’s aren’t super impressive. The b&c 18ds looks better for less money.
The 18ipal does look good. The BMS 18n862 should be pretty competitive also.

Chris
I'm not too positive what you mean "don't look super impressive" as they are pretty dang nice, what about the 18DS looks better?

I did a quick sim, I checked my numbers and it looks pretty impressive for the NSW. NSW Green, 18DS grey.
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post #15 of 58 Old 12-09-2019, 05:46 PM
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Quote:
Originally Posted by Trimlock View Post
I'm not too positive what you mean "don't look super impressive" as they are pretty dang nice, what about the 18DS looks better?



I did a quick sim, I checked my numbers and it looks pretty impressive for the NSW. NSW Green, 18DS grey.


In that box size, the 18sw will model much closer. The ds likes small boxes.

I just don’t see anything that makes the eminence better than the b&c’s for more money. Plus you’re stuck with 8ohm only.
I’d just stick with the proven design.

Unlike the 21 NSW, which has very impressive numbers compared to the b&c offerings. I believe that justifies the price difference, as I just ordered a pair on Black Friday.

Chris
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post #16 of 58 Old 12-09-2019, 07:02 PM
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Have you considered putting two 18s in each cab?

More power dense than a single driver. A pair of 8 ohm Lavoce San184-03 is only $680 before discounts.
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post #17 of 58 Old 12-09-2019, 07:09 PM
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Quote:
Originally Posted by a77cj7 View Post
In that box size, the 18sw will model much closer. The ds likes small boxes.

I just don’t see anything that makes the eminence better than the b&c’s for more money. Plus you’re stuck with 8ohm only.
I’d just stick with the proven design.

Unlike the 21 NSW, which has very impressive numbers compared to the b&c offerings. I believe that justifies the price difference, as I just ordered a pair on Black Friday.

Chris
I chose the box size because the OP wanted to downgrade, besides the price difference is only $50. The NSW 18" should be just a proven, I doubt they'd put the NSW tag on an 18" that only provides minimal effects. The SW will be more money than the NSW, the SW only modeled a bit better but should offer better everything for that cost.

The NSW also models well with smaller boxes, does very good in large boxes too. B&C and the NSW should offer a near indestructible design. Its just another option and I would think it foolish to not consider it considering it is a contender.

The 8ohm is the only downside I can see, its not really that big of a downside either.

oops, I thought there was an 18SW152, guess the SW and DS are the same price. Besides, the SW only models closely to the NSW, I'd anticipate it having a better low end. If it were between the DS and the NSW18 it looks pretty handily in the NSW based on the model unless you are really bothered by the 8ohm.

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post #18 of 58 Old 12-09-2019, 07:57 PM
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Quote:
Originally Posted by Trimlock View Post
I chose the box size because the OP wanted to downgrade, besides the price difference is only $50. The NSW 18" should be just a proven, I doubt they'd put the NSW tag on an 18" that only provides minimal effects. The SW will be more money than the NSW, the SW only modeled a bit better but should offer better everything for that cost.



The NSW also models well with smaller boxes, does very good in large boxes too. B&C and the NSW should offer a near indestructible design. Its just another option and I would think it foolish to not consider it considering it is a contender.



The 8ohm is the only downside I can see, its not really that big of a downside either.



oops, I thought there was an 18SW152, guess the SW and DS are the same price. Besides, the SW only models closely to the NSW, I'd anticipate it having a better low end. If it were between the DS and the NSW18 it looks pretty handily in the NSW based on the model unless you are really bothered by the 8ohm.

I thought it cost $630, $580 is closer. Last time I looked at the specs, they hadn’t released them yet.

The NSW’s higher fs didn’t look great either, but it seems to model fine.

It seems to me that the NSW is a direct competitor to the 18SW115, at $50 dollars more, and no 4ohm option. I wouldn’t chose it for those reasons, but its not enough reason not to consider it. I do like the “made in usa” part.

The DS is a stronger motor, made for small box or horn loading.

As to not proven, I haven’t seen reviews of anyone running one yet. I was slightly nervous buying the 21 as a new product, but at least ricci’s flogged one of those, and some people on the forum have been running them for some time.

Honestly, I rarely recommend the DS even though I own a pair. For most people, the performance of the Saf184.03 (8ohm) or TBW100 (4ohm) are close enough that the cost difference isn’t worth it to the higher end woofers.
The OP’s case is one of the few, where he’s trying to match 21ds performance from an 18 in a smaller box.
Since he wants the full displacement, the sw, ds, and nsw fall short anyway. The 18IPAL and BMS 18n862 are the only two I know of that can do it.

Chris
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post #19 of 58 Old 12-09-2019, 08:34 PM
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The DS has amazing normalized motor force but loses a good bit due to inductance. The IPAL being the king of motor force, probably won't extend as low as they want, the IPAL is intended for bass but not ULF. The SW has great motor force and I'm betting (i know assumptions, but I'm basing it on the 21" here) that it has similar to the NSW 21". Besides, the motor force shouldn't be the only thing looked at here though.

The BMS would be the best bet here but those are hard to find outside of Europe. If you wanted one you would have to be watching sites constantly. You could try assistance audio and see if they will special order you some, I think they are the only large retailer of BMS products.
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post #20 of 58 Old 12-09-2019, 08:46 PM
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Quote:
Originally Posted by Trimlock View Post
The DS has amazing normalized motor force but loses a good bit due to inductance. The IPAL being the king of motor force, probably won't extend as low as they want, the IPAL is intended for bass but not ULF. The SW has great motor force and I'm betting (i know assumptions, but I'm basing it on the 21" here) that it has similar to the NSW 21". Besides, the motor force shouldn't be the only thing looked at here though.



The BMS would be the best bet here but those are hard to find outside of Europe. If you wanted one you would have to be watching sites constantly. You could try assistance audio and see if they will special order you some, I think they are the only large retailer of BMS products.


Where are you getting that the IPAL won’t perform low? It has an fs of 32hz, similar to the rest. Technically none of the mentioned woofers are meant to play low, just crazy people like us make them do it anyway.

I had my ds in effectively the box recommended by b&c, 3.7cf tuned to 38hz. Perfectly flat response 40hz-up with great spl. But where’s the fun in that, so I put it in a mini dev with a 20hz hpf and see what it can really do.

Agreed on the BMS.

Chris
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post #21 of 58 Old 12-09-2019, 08:54 PM
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Quote:
Originally Posted by Petr Berka View Post
Yes, striving for most "power output" density, or SPL/bandwidth/box size ratio.
For home usage, I actually use about full excursion capabilities of the driver, as I can afford to EQ the box heavily under the port tuning. While for PA, the box is tuned low, so the cone excursion at about 50Hz is also little higher than normal. I'm perfectly fine with 21DS, it's just I wanted something top notch and buy myself something awesome for rewards, and being able to move these boxes. The more they're movable, the more often I take them out. 18IPALs seem to hold its own against DS, losing about 0.5-1db on average compared to 21DS. That seems to be fair trade for more fun outside.
I don't believe @Ricci uses the B&C/IPAL amplifiers for his IPALs, nor does PSA. The 18DS115 seems better for a smaller enclosure than 18IPAL.

Have you considered the 15DS115s? https://www.bcspeakers.com/en/produc...-0/8/15ds115-8
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post #22 of 58 Old 12-09-2019, 09:37 PM
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Quote:
Originally Posted by Trimlock View Post
I'm not too positive what you mean "don't look super impressive" as they are pretty dang nice, what about the 18DS looks better?

I did a quick sim, I checked my numbers and it looks pretty impressive for the NSW. NSW Green, 18DS grey.

I presume those plots are freq resp, so not very useful, assuming EQ is used.

SPL would be more informative.

Noah
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post #23 of 58 Old 12-10-2019, 01:23 AM - Thread Starter
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Wow, that escalated quickly. 🙂



Trimlock:



18DS has more than double the static motor force, and once it does not go against ones needs, lower Qms and greater suspension stiffness is also better.

As mentioned, sensitivity curve is not much of a concern, efficiency is. In that resort, I believe tables would turn. Also, 226l (8cu.ft.) is rather absolutely out of question. I am going wicked. My 21”s are now in like 4,5cu.ft, and those 18”s will work in under 4cu.ft. Tuning possibly 28Hz.

NSW might win with possibly more cone excursion available (under port tuning).

As far as I know, the inductance doesn´t absolutely ruin efficiency, and more so NOT at or under 50Hz. It´s like a buzzword for last year or what. Yes, It does its thing, but nowhere near to ruining speaker performance for LF and ULF.

Motor force should not be the only one to look at, but plain wire will not move anything, to make a sound. Coil with large force behind it and great displacement sure will. It´s that easy, when all other things are equal.



Samps: That would be too big for me. Maybe two 15s, Like, 2x15DS115 would do some damage….



A77cj7: Well, both 21DS and 18DS/18IPAL are not displacement limited above 30Hz for my usage. That way I think that I could go lower with port tuning, to lower the cone excursion at lower frequencies, to ~match the 21”. Not exactly, but close enough to go with the compromise of the smaller box.



Marc Alexander: Yes, I´m considering 15DS115 too. Regarding efficiency and max SPL output, it doesn´t look like 18DS115 stands a chance compared to 18IPAL.



Noah katz: THIS. 🙂 Thanks.

I was thinking about 18IPAL in 95-100l of volume, and then doing some magic with it.
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post #24 of 58 Old 12-10-2019, 11:08 AM
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Quote:
Originally Posted by Petr Berka View Post
...greater suspension stiffness is also better.

How so?

In my mind, suspension stiffness just adds to the box air spring, to the detriment of bass extension and efficiency.

Noah
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post #25 of 58 Old 12-10-2019, 11:16 AM
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Quote:
Originally Posted by noah katz View Post
I presume those plots are freq resp, so not very useful, assuming EQ is used.

SPL would be more informative.
Those are SPL.

As for the question about CMS, the stiffness is often attributed to low Fs and better linearity. Its NOT universal but Pro audio often lowers Fs through CMS without adding MMS.
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post #26 of 58 Old 12-10-2019, 12:10 PM - Thread Starter
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Noah katz: that is somehow incorrect. The box spring can, and often behaves differently than the speaker spring. Mechanical dampening and restoring force attenuates ringing and foreign spring action. That gives you more control over the system. You are right that it is eating into efficiency, there comes the advantage of IPAL motor, overpowering stiffer suspension rather "easily". So the amplifier and the speaker is the boss, not the enclosure, so to speak.

Trimlock: I am not sure how manufacturers of PA drivers handle Cms, but these speakers are rather stiff, at least to my understanding. That means lower Cms and higher Fs. But with those newer drivers, things turn back again, and we're seeing some 20-30Hz drivers "recently" again.
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post #27 of 58 Old 12-10-2019, 12:48 PM
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Hi Petr,

I looked into the 18Sounds 21"/PowerSoft iPAL combo kit about a year ago and posted about it in a different thread. Bottom line it doesn't seem to be a good DIY approach, at least if you're wanting to use the iPAL pressure feedback system. The 18Sounds sales guy indicated that placement of the pressure sensor in the enclosure and then DSP tuning after that is very critical. He indicated that 18Sound would not be willing to invest assistance with a one-off DIY solution, and instead recommended the canned enclosure design shown in the kit link below.

EDIT: Here's a link to the 18Sound dual 21" iPAL enclosure drawing.

Quote:
Originally Posted by darrellh44 View Post
I've been looking into using two 18Sound 21iD drivers with an 18Sound/iPALMOD kit (turns out the iPALMOD amp is available for hobbyists), instead of two B&C 21iPAL drivers and a SP1-4000. However I just saw on another forum where you and Ricci were discussing noise issues with the iPALMOD amps a few months back. Do you know if PowerSoft has make any plans to address these noise issues?

For anyone who is curious about the 18Sound/iPALMOD kit, here is a link. This kit is available in the states from Universal Music (contact Jean Costa (305) 499-9393). For my application, I don't plan on using the cabinet plans in the link. I think the kit only includes the PowerSoft iPALMOD amp, DSP 2CH module, DPC pressure sensor, faceplate/heat-sink, and PowerSoft's system software/GUI. The 18Sound drivers are sold separately.

Thanks,
Darrell
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Thanks for the reply, Josh.

I did speak with Jean Costa (Universal Music) on the phone again after my last post. I asked him directly about the noise issue with the ipalmod amps, but he didn't really give a answer. He then seemed to back off on whether the ipalmod kit was really available/suitable for DIYers. He said even though a baseline DSP setup is provided for their dual opposed ported enclosure, it would still require quite a bit of additional tuning for a different box, especially for a sealed enclosure that I wanted to do. He said even the placement of the diff pressure sensor is critical, and that a one-off DIY designer probably wouldn't get much support from Powersoft. Also when I told him my application was a home theatre, he kinda thought I was crazy - way too much overkill he said. I guess he doesn't come on AVS Forums that much.
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Originally Posted by darrellh44 View Post
Yeah, during the second conversion I got the feeling he was just trying to discourage me and was saying whatever. The first time I talked to him, he was a lot more encouraging.

BTW the price Jean quoted for the 18Sound 21iD drivers is about half of what I've seen advertised for the B&C 21iPALs. The Powersoft ipalmod amp kit on the other hand was about 2.5x the cost of an SP1-4000. Both amps are plate mountable and include DSPs, but the big difference is the ipalmod amp has about twice the rated output and of course has the differential pressure feedback sensor.

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Last edited by darrellh44; 12-10-2019 at 12:58 PM.
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post #28 of 58 Old 12-10-2019, 01:21 PM
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Quote:
Originally Posted by Trimlock View Post
Those are SPL.

Are you sure?

The graph shows 20 dB of bass.


Quote:
Originally Posted by Trimlock View Post
As for the question about CMS, the stiffness is often attributed to low Fs and better linearity. Its NOT universal but Pro audio often lowers Fs through CMS without adding MMS.
Cms is the inverse of stiffness. High Cms/low stiffness lowers Fs.

High stiffness is usually a detriment to linearity, because suspension stiffness itself is not linear, as seen in any Klippel graph.



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Originally Posted by Petr Berka View Post
...that is somehow incorrect. The box spring can, and often behaves differently than the speaker spring. Mechanical dampening and restoring force attenuates ringing and foreign spring action.
How so?

Yes, per above the suspension spring behaves differently - it's less linear than the box air spring.

Damping and restoring force (spring stiffness) are entirely different and independent parameters.

Damping attenuates ringing, stiffness increases it, as evidenced by Qt increasing with higher suspension and/or box air spring stiffness.

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post #29 of 58 Old 12-10-2019, 04:02 PM
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Quote:
Originally Posted by noah katz View Post
Are you sure?

The graph shows 20 dB of bass.




Cms is the inverse of stiffness. High Cms/low stiffness lowers Fs.

High stiffness is usually a detriment to linearity, because suspension stiffness itself is not linear, as seen in any Klippel graph.
what do you mean the graph shows 20db of bass? Its SPL, the graphs look similar with Petr's requirement of 4.5cu.f and 28hz tune in regards to mid bass.

As for CMS, *shrug* its often stated, I know which way CMS is moved but certain manufacturers claim their linearity is related to the CMS and a few other factors. I wouldn't believe linearity based on a CMS number alone, much like I wouldn't base motor strength only on the normalized Bl^2/Re. Do you have a graph that shows a stiff suspension and poor linearity? I can't think of one off of the top of my head.
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post #30 of 58 Old 12-10-2019, 10:08 PM
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Quote:
Originally Posted by Trimlock View Post
what do you mean the graph shows 20db of bass?
The vertical axis shows 18 dB SPL at 20 Hz.


Quote:
Originally Posted by Trimlock View Post
Do you have a graph that shows a stiff suspension and poor linearity? I can't think of one off of the top of my head.

Every driver I've seen a Klippel for shows nonlinear Kms.

Like the 16th image here https://www.google.com/search?q=klip...JhovA-M:&vet=1

I've shown you mine, now you show me yours.

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