Anyone using partial or full B&C IPAL solution?

I think I know you from facebook and some forums, I guess you are the one with the 12x double 18NTLW5000 reflex right? :D  I am Fritz from Fritz Audio Berlin.

Anyway, send me your Email adress as a pm and maybe I can help.

But I already can tell you that you won't be very happy with the results

using the IPAL Mod with the 18NTLW5000.(-4?).

The Ipal mod needs very strong drivers or better with a very high bl²/re to mms ratio.

This is not only theory, I tested the Ipal mod with 18SW115-8 and also "G03229" Lacoustics KS28 driver and there was no major improvement in impulse response or dynamic but just a bit less nice sound compared to using Lab PLM14000. 

Even with the 18DS115-4 the improvement using Ipal Mod instead lab g was not as great as with the 18IPAL drivers. 

My initial plan was to use the 21DS115-4 with Ipal mod and DPC, yes, it is a bit more tight but it's not a magical thing that makes a 21inch sound like a 12" in a sealed box.

With the 18IPAL in a 105L 35hz tuned reflex enclosure which is already "tight"sounding using Lab PLM14000, with the IPAL and DPC it sounds just better and kind of "processed", very clean and tidy, just the very deep notes at tuning, the typical "bassreflex full deep bass sound", suffers a bit from it.

But the important thing when using the 18IPAL is also the advanced limiting of the IPAL mod.

You really need it! You could use Lab G or the china clones or other amps, but you need a lot of voltage to bring the heavy punch out of the 18IPAL in a reflex, but with the same voltage

@ tuning frequency, for example 160Vpeak, you would feed the driver 6,4kW which is much too much.

Powersoft X or T series would work also btw.

Can I ask why you consider to use the 18NTLW5000 with the IPAL mod? Just for testing?

Btw PK Sound Gravity 218 uses 18IPAL and IPAL mod solution,

but I really don't understand how it could sound any good except at very low bass notes, because the encolsure is way too large, from my guess 180L per driver, for the 18IPAL and even with the IPAL mod it can't compensate such a large volume with the DPC.
But maybe I miss something here because I can't imagine a company like this would produce something in large format without testing it extensively.

It seems you have a good amount of experience with the iPal MOD amplifier  modules.  I currently run a system with about 200 of them, so I also have some experience with them, for the past 13 years.  However, recently we've come across a new problem with them.  We've just purchased several new modules, and those  new ones along with several of the units we've had in service  for several  years are exhibiting the same problem.....Low ouptut levels.

As an example, we typically test these speakers by  inputing .018 volts to the input to achieve approximately 89 db.  But these units with the problem require .180 volts to  achieve the same output level.  we use DSP in a device prior to these amps, so all we're using the onboard DSP for is adding gain (+16db).  We've checked the EQ filters, and there are none engaged, the level appears to be set, and changing that does indeed change the output level, so I/we believe we're actually in control of the amplifiers...

We've swapped out input/control  modules and the problem seems to stay with the amplifer modules.  It's just weird that this issue  came up in both new amp modules as well as units that have been in service for 10 years.

Just wondering if you've every come across this issue before, and if so, what did you find  was the cause?

Looking for some kind of clue here...thanks.

I can be reacheched here on the forum, or if you reply here, I'll send you my email  address....thanks,,,,lets seeif we can get to the bottom of this..

Art

'smelp!

Have you measured the TS Parameters of the faulty drivers versus the non-faulty drivers to determine if the parameters coincide among-st one another? 

Best Regards,