This is used as roof surround speakers in GM BMW land rover and many more vehicles.
It is the speaker astounding me the most. Here is why. This unit is approximately palm size, for this size planar speaker I can find for sale on line it is usually an above mid tweeter but not able to reach 20k. and a very narrow high frequency spread angle, it is not be able to cover mid range or used as a tweeter. But this one I find out to deep as 100hz if you hear it near.
What is more amazing is that if u test it as a headphone it sounded just like audeze big planar, better than my moded fostex planar. from the deepest bass I have ever heard with any speaker to the highs I cannot hear the upper limit.
It is the only speaker I have heard be able to use as headphone and achieves hi-end performance. I think the speaker has the lowest distortions in the market for a full range. Of course u need many of them to really show the bass if used as a speaker because the x-linear is small.
With it, I came up an idea, a two way speaker with a 18-21 inch woofer and four this planar, crossover at 200-300hz to lower the distortions from coil speakers. I think this is not possible before.
It is the speaker astounding me the most. Here is why. This unit is approximately palm size, for this size planar speaker I can find for sale on line it is usually an above mid tweeter but not able to reach 20k. and a very narrow high frequency spread angle, it is not be able to cover mid range or used as a tweeter. But this one I find out to deep as 100hz if you hear it near.
What is more amazing is that if u test it as a headphone it sounded just like audeze big planar, better than my moded fostex planar. from the deepest bass I have ever heard with any speaker to the highs I cannot hear the upper limit.
It is the only speaker I have heard be able to use as headphone and achieves hi-end performance. I think the speaker has the lowest distortions in the market for a full range. Of course u need many of them to really show the bass if used as a speaker because the x-linear is small.
With it, I came up an idea, a two way speaker with a 18-21 inch woofer and four this planar, crossover at 200-300hz to lower the distortions from coil speakers. I think this is not possible before.
https://www.ebay.com/itm/113327817080
Been seeing these for sale parted out from cars for several years now. Never purchased one to test against all the others out there.
Been seeing these for sale parted out from cars for several years now. Never purchased one to test against all the others out there.
Single-ended planar-magnetic, eh? Kind of one of the old "leaf" tweeters writ large or an Apogee or Magnepan QR series shrunk down. Looks like it'd be fun to play with and the cavity resonance will be less pronounced only having one set of magnets. Don't push them too hard or too low, though. Linear range will be very limited by using one set of magnets (hence why most going this route either do push-pull magnets or make the diaphragms very large) so keep that in mind while you're thinking of how low you can push them without distorting too badly.
Thanks for the nice tear-down pics and info. These go by the name "Electro Dynamic Planar Loudspeaker" (EDPL), see
https://in.harmankardon.com/blog-audio-innovations.html and https://thenewisyou.wordpress.com/2...our-passengers-harman-individual-sound-zones/
--> Do you know of any other specific car models using these, or is there a source listing such models? From which GM vehicle did this speaker come?
I did an extensive search which car models use these, but only found 2 BMWs (X1 and 3 series Touring, "harman/kardon" sound system), and 2 Ferraris (458 Italia, and FF F151, "JBL" sound system). Did it just out of curiosity, and because knowing the car model or even speaker part # helps finding those online, as the sellers don't always mention Harman or EDPL. In Europe, I found those at 80 € or $, hopefully I can get them cheaper under a different part #.
Much appreciated
Does anyone here have some more information or experience with these to share?
I'd also love to know the size, would be great if someone could measure the length/width of the "baseplate" section for me.
I am very interested in sourcing a bunch of these and experimenting with them. Trying them in a tall array, making a push/pull configuration.. Making a fancier "case".
So far I have been able to find the following part numbers:
BMW: 9245810, 9143154 (probably the same speaker, just different plastic enclosure)
Ferrari: 255697 (same manufacturer, but more narrow)
I'd also love to know the size, would be great if someone could measure the length/width of the "baseplate" section for me.
I am very interested in sourcing a bunch of these and experimenting with them. Trying them in a tall array, making a push/pull configuration.. Making a fancier "case".
So far I have been able to find the following part numbers:
BMW: 9245810, 9143154 (probably the same speaker, just different plastic enclosure)
Ferrari: 255697 (same manufacturer, but more narrow)
First I'd like to ask everyone again, does anyone know of other car models that are using this Harman driver?
The metal baseplate is 200 x 77 mm, it is from a BMW 6951981. As far as I can tell, all of these Harman speakers (probably also those for Ferrari and other brands) are quite the same inside (the metal plate, magnets, membrane, conductors, felt sheet), only with production tolerances and maybe minor changes over the years. And with different plastic housings and holders which are adapted to each vehicle model, but should not change the acoustics that much.
Keep in mind that these are single-side (unsymmetric) drivers, no magnets on the front side of the membrane. This means that the magnet field strength is very dependent on the membrane excursion, and this means significant distortion at low frequencies or higher SPLs. Also, the drivers themselves have an impedance (in this case almost purely resistive) below 2 Ohms, which is challenging for most amplifiers. In the car this is OK, there are several connectors and several meters of (not very thick) wire between driver and amp, so that the amp probably sees a total of almost 4 Ohms.
You might consider e.g. the GRS PT6825-8 driver at 90€ (the Harman is anywhere from 50€ heavily used to 140€ new), prices in USD should be similar. The GRS has symmetric magnets ("push-pull") and therefore low distortion, amp-friendly 8 ohms, and almost same dimensions as the Harman driver. But you need flat female spade connectors (German: Flachstecker / Flachsteckhülse) because you definitley should not solder at the driver terminals. Good luck
The metal baseplate is 200 x 77 mm, it is from a BMW 6951981. As far as I can tell, all of these Harman speakers (probably also those for Ferrari and other brands) are quite the same inside (the metal plate, magnets, membrane, conductors, felt sheet), only with production tolerances and maybe minor changes over the years. And with different plastic housings and holders which are adapted to each vehicle model, but should not change the acoustics that much.
Keep in mind that these are single-side (unsymmetric) drivers, no magnets on the front side of the membrane. This means that the magnet field strength is very dependent on the membrane excursion, and this means significant distortion at low frequencies or higher SPLs. Also, the drivers themselves have an impedance (in this case almost purely resistive) below 2 Ohms, which is challenging for most amplifiers. In the car this is OK, there are several connectors and several meters of (not very thick) wire between driver and amp, so that the amp probably sees a total of almost 4 Ohms.
You might consider e.g. the GRS PT6825-8 driver at 90€ (the Harman is anywhere from 50€ heavily used to 140€ new), prices in USD should be similar. The GRS has symmetric magnets ("push-pull") and therefore low distortion, amp-friendly 8 ohms, and almost same dimensions as the Harman driver. But you need flat female spade connectors (German: Flachstecker / Flachsteckhülse) because you definitley should not solder at the driver terminals. Good luck
As I experienced, the efficiency is lower from my subjective comparison to normal coil speaker. But I don't think that's a problem. However the impedance is low as well. thats for the car amp that have low power supply voltage to get enough juice. I don't think 2.2 ohm Dc resistance is that a big problem.
I am sure Gm(buick GL8 in china) land rover range rover, bmw Ferrari all have them ,maybe more.
If u can get them cheap like in china, 20 dollars a unit (not that cheap in Chinese currency). how it can be gone wrong. If expensive as a purpose designed planar speaker, why bother it.
I am sure Gm(buick GL8 in china) land rover range rover, bmw Ferrari all have them ,maybe more.
If u can get them cheap like in china, 20 dollars a unit (not that cheap in Chinese currency). how it can be gone wrong. If expensive as a purpose designed planar speaker, why bother it.
Yes China Idlefish market has them $15-40ea, many different part-numbers and sellers. Surely too large for headphones no? And not cheap enough for omni polytopes.... Maybe stick-to-ceiling speakers above the bed?
Some years ago TDK sold a portable CD case called "I'm a Speaker", square flat panel per channel. Great with dual subs.
Some years ago TDK sold a portable CD case called "I'm a Speaker", square flat panel per channel. Great with dual subs.
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Last night I ordered four of these for around $180 shipped, 160€. Excited to experiment. If they're available in China for even cheaper, I might end up with 30 of them one day..
Figured it's worth a try because per speaker that's still less than half of the GRS. I imagine it shouldn't be too hard to modify these to push-pull.
Also did a lot of research, found more part numbers..
These speakers were designed by Harman and used in "BMW, SGM, Kia, Ferarri" cars, where Kia includes at least Hyundai as well. They were only available with the Harman Kardon / JBL / Infinity audio upgrade options.
They were used in the roof, front and rear, as well as in various pillars in some cars and possibly even doors on a few.
At least for some models, the idea was to use directional drivers to create individual "sound zones" so that everybody in the car can enjoy good audio without completely ruining staging, or to limit certain information to certain zones. I think usually they were just plain center speakers. No idea why Ferrari used them (in pillars), as those audio upgrades already included enough (fancy) drivers to cover the whole range.
Generally, they are always referred to as EDPL, I guess planar loudspeaker does not sound as "revolutionary".
There was also a newspaper article (being quoted on another audio forum) that mentioned a 25 micrometer "thermoplastic diaphragm".
BMW called them "Mittelhochtöner", meaning mid-tweeter. That does not reveal much about usable range, sadly, and so far I have not found any info on power handling.
These were always powered by individual channels of a DSP amplifier, so there's no passive crossovers to base a best guess on.
They filed a lot of patents for such a simple driver, e.g. for the "automotive EDPL "WaveBender" lens utilizing the same science as the JBL Pro CBT line array", I assume that's the smiley face mouth / half moon looking slit in the plastic. Could be very interesting for some applications, I have not seen a waveguide like that anywhere else before.
Search for EDPL on https://sites.google.com/site/equitysndinv/Home/steve-s-professional-bio for a (incomplete?) list of patents (as well as more info about the dude leading the development).
I'm planning to read through all of these patents today and will compile all the interesting information. Some of them sound very exciting, like "Acoustically enhanced electro-dynamic loudspeakers".
Figured it's worth a try because per speaker that's still less than half of the GRS. I imagine it shouldn't be too hard to modify these to push-pull.
Also did a lot of research, found more part numbers..
These speakers were designed by Harman and used in "BMW, SGM, Kia, Ferarri" cars, where Kia includes at least Hyundai as well. They were only available with the Harman Kardon / JBL / Infinity audio upgrade options.
They were used in the roof, front and rear, as well as in various pillars in some cars and possibly even doors on a few.
At least for some models, the idea was to use directional drivers to create individual "sound zones" so that everybody in the car can enjoy good audio without completely ruining staging, or to limit certain information to certain zones. I think usually they were just plain center speakers. No idea why Ferrari used them (in pillars), as those audio upgrades already included enough (fancy) drivers to cover the whole range.
Generally, they are always referred to as EDPL, I guess planar loudspeaker does not sound as "revolutionary".
There was also a newspaper article (being quoted on another audio forum) that mentioned a 25 micrometer "thermoplastic diaphragm".
BMW called them "Mittelhochtöner", meaning mid-tweeter. That does not reveal much about usable range, sadly, and so far I have not found any info on power handling.
These were always powered by individual channels of a DSP amplifier, so there's no passive crossovers to base a best guess on.
They filed a lot of patents for such a simple driver, e.g. for the "automotive EDPL "WaveBender" lens utilizing the same science as the JBL Pro CBT line array", I assume that's the smiley face mouth / half moon looking slit in the plastic. Could be very interesting for some applications, I have not seen a waveguide like that anywhere else before.
Search for EDPL on https://sites.google.com/site/equitysndinv/Home/steve-s-professional-bio for a (incomplete?) list of patents (as well as more info about the dude leading the development).
I'm planning to read through all of these patents today and will compile all the interesting information. Some of them sound very exciting, like "Acoustically enhanced electro-dynamic loudspeakers".
I'm going to put them in my a-pillars of my SW20 and see how low I can push them at 50W RMS. If I can cross them at 500-600 Hz @24 dB/oct. that would be good enough. I think I'll have them recessed by a few cm and fiberglass a horn shape.
Since I'll have a front subwoofer crossed high, and cabin gain starting above 100 Hz, I might even get away with a low-volume DSP preset where only these two panels and the sub are playing.
I saved the part number searches on eBay and I will probably get every one I can find for up to 40€ shipped and once I've collected enough, I will build a pair of simple dipole line source arrays. That's what I always dreamed about and at this price it's finally feasible for me.
I don't listen at high volume at home, so I imagine if I just mod a few of them for push/pull and higher excursion, and DSP, I'll play them full range.
At 20cm length they're sadly not practical for headphone use.
The smaller version, used at least in one Ferrari model, is just as long (60x200mm, the regular version is 80x200mm).
Since I'll have a front subwoofer crossed high, and cabin gain starting above 100 Hz, I might even get away with a low-volume DSP preset where only these two panels and the sub are playing.
I saved the part number searches on eBay and I will probably get every one I can find for up to 40€ shipped and once I've collected enough, I will build a pair of simple dipole line source arrays. That's what I always dreamed about and at this price it's finally feasible for me.
I don't listen at high volume at home, so I imagine if I just mod a few of them for push/pull and higher excursion, and DSP, I'll play them full range.
At 20cm length they're sadly not practical for headphone use.
The smaller version, used at least in one Ferrari model, is just as long (60x200mm, the regular version is 80x200mm).
Thanks all, highly interesting! Great to see this thread come to life
Would be great if you could post those part numbers here
Good idea, it won't be perfect since there is this silicone-glue rectangle and the contacting rivets which prevent mounting two steel frames face-to-face with perfect symmetry. But still better than nothing, should increase linearity and also efficiency. But you will need a good holding structure for keeping those 2 frames together against the large repelling force, and you should take extreme precautions to prevent the 2 frames from shifting sideways relative to each other, because they will then start to attract and then there is probably no going back, depending on how good the magnet glue still works... check out the old video of Tyll on YT ("Anatomy of a Planar Magnetic Headphone Driver"), he destroyed one push-pull driver when trying to disassemble it, same can happen during assembly.
Those patents relate for the most part to production technologies that make such a driver feasible for mass production. The "wave bender" in my view is mostly a marketing gimmick, I couldn't really hear or measure a major change or improvement in directivity. And that is not to be expected either, it's just thin flat plastic, and the banana-shaped opening will mostly widen high-frequency directivity by virtue of a smaller radiating width, which can be achieved just as well by a straight slit. Other than that, it seems to shift the main axis of high frequency radiation by maybe 10°, which really isn't the miracle it is supposed to be.
That smile is not that simple. The shape must be engneered extensively. It affect the damping of some part of the membrane,further more dampens the standing wave on the membrane besides direction, radiation angle and of course fq response. Modding the unit will make it worth 99.99% unless one have the ability to simulate on computer and test.
I'm sorry to ruin your fun, but all this talk of modding them to be push pull and higher excursion is not at all realistic. You'll waste tons of time and never likely get a good result. You want push pull, lower cut off frequency and higher output? Pay for a driver that already does it, because modifying these is not the solution. Pay up for some Radian product and be happy. It will likely make for a killer car audio SQ system and still be cheaper than the rip off prices car specific brands sell their high end offerings for.