Stumbled across this RL 921K speaker. This design would be amazing for the "wife acceptance factor". How would the sound waves coming off the woofer not royally screw up the mid and tweeter response?
Does anyone speak German and can translate what the design idea is here?
Does anyone speak German and can translate what the design idea is here?
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Not unusual, car speakers like this have been around a long time.
Ever hear of the Jensen Triaxial?
And who said this mounting method doesn't royally screw things up?
Ever hear of the Jensen Triaxial?
And who said this mounting method doesn't royally screw things up?
They don't seem to have much to say about the mini baffle.
I also notice that the measurements include a 45 degree response plot but no other angles. I can't speak to their intention but using this method can indicate a positive trend without drawing much attention to possible negatives.
I also notice that the measurements include a 45 degree response plot but no other angles. I can't speak to their intention but using this method can indicate a positive trend without drawing much attention to possible negatives.
Never heard of it but I've not researched others designs until recently.
I would think the low frequency sound waves hitting the back of the mid and tweeter would affect their performance.
I would also think the mid and tweeter in the way of the woofer would affect the woofer's performance as the sound bounces back towards the come off of the mid/tweeter mount.
It's really kind of a mess. Even highly developed true coaxial drivers still have real problems.
One thing I can say, Geithain monitors sounds really good.
Mini baffles have some absorptive material behind the mid driver, which should create cardioid radiation (I think it's still more dipole with reflection from the bass driver, kind of a second order dipole?). The bass cabinets of at least the big monitors also have a cardioid design with a port on the back wall, I don't know how useful that is.
The Polish magazine has measurements of the large monitors and some photos: https://audio.com.pl/testy/stereo/kolumny-glosnikowe/329-me-geithain-rl800k#laboratory
Here DIY attempts to replicate the design and some extra information:
https://www.groundsound.com/GalleryThomasM.php
Mini baffles have some absorptive material behind the mid driver, which should create cardioid radiation (I think it's still more dipole with reflection from the bass driver, kind of a second order dipole?). The bass cabinets of at least the big monitors also have a cardioid design with a port on the back wall, I don't know how useful that is.
The Polish magazine has measurements of the large monitors and some photos: https://audio.com.pl/testy/stereo/kolumny-glosnikowe/329-me-geithain-rl800k#laboratory
Here DIY attempts to replicate the design and some extra information:
https://www.groundsound.com/GalleryThomasM.php
Those are indeed Geithan speakers, a well known and respected german speaker brand, but only active in German speaking Europe (Germany, Austria, German speaking Switzerland). They were used in the 80's and 90's as monitors in a lot of broadcast and recording studio's, certainly the big names like ARD used them a lot. They are still very popular and measure quiet decent.
But this is a small family bussiness, not interested in conquering the world, so they restrict their support only to the EU, and don't sell officially outside of that. Off course there is grey market import, but no waranty or support is guaranteed outside the EU.
THe baffle in front of the woofer is not really a problem as that woofer is a subwoofer, not a midwoofer (that is on the baffle). So the frequncy waves are to big to be really affected by that baffle.
But this is a small family bussiness, not interested in conquering the world, so they restrict their support only to the EU, and don't sell officially outside of that. Off course there is grey market import, but no waranty or support is guaranteed outside the EU.
THe baffle in front of the woofer is not really a problem as that woofer is a subwoofer, not a midwoofer (that is on the baffle). So the frequncy waves are to big to be really affected by that baffle.
One of course could point to Genelec. The Ones have similar construction. And more info in their brochures.
Hi,
here are other measurements of a Geithain: ME Test
It works fine in my small room. If you use active crossover, delay .. it s good.
You get coaxial And cardioid
My own with Sica Coax:
here are other measurements of a Geithain: ME Test
It works fine in my small room. If you use active crossover, delay .. it s good.
You get coaxial And cardioid
My own with Sica Coax:
Agree on the active thing with front drivers delay. It is novel and high WAF, but it kinda defeats one of the purposes of the coax drivers: to put tweeter or other "faster" driver magnet behind slower one to make the response arrive at your ears at the same time
REW measurements with loopback for timing of (any) tweeter vs woofer clearly show that
REW measurements with loopback for timing of (any) tweeter vs woofer clearly show that
Not sure about fast or slow magnets.....is that a thing?
Measure the distance between the point source of the woofer and the other drivers......then apply the speed of sound to get the offset......it's an insignificant value..........turning your head 10 degrees would have more of an audible effect. Some of things folks fuss over is really quite silly these days. Those are highly regarded monitors
Measure the distance between the point source of the woofer and the other drivers......then apply the speed of sound to get the offset......it's an insignificant value..........turning your head 10 degrees would have more of an audible effect. Some of things folks fuss over is really quite silly these days. Those are highly regarded monitors
As long as the top drivers are sealed, the small front baffle will have more effect on the woofer. Not the first time we have seen rear-mounted woofers peaking out of smaller hole in the baffle.
Linn has been doing simila4 for years.
Maybe not somuch now.
dave
Linn has been doing simila4 for years.
Maybe not somuch now.
dave
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Measured SICA coax couple of days ago: impulse response shows ~0,122ms for woofer, ~0,076ms for tweeter.
0,046ms difference, so that is ~16cm difference.
Wrong. Play with any simulation program and see that Z depth of 10+ cm will do much more difference that 10 degrees. On tilting you tilt all the speaker with all the drivers, which more or less do predicted and smooth transition. On the other hand if you put "fast" physically driver in front and do not apply delay to it - most likely you will get nonsense.
Maybe it is more like ~1,6cm different?
Never heard fast/slow magnet...
If you sit in front of an normal 3way speaker, passive: the tweeter has the shortest way to your ear, the woofer the longest way, cause of the angle, the woofer placed under tweeter and midrange
Most 3way speaker are like this, and that s nonsense?
Greetings
Isn't the 'magnet' just another way of saying the acoustic centre? On an international forum it can help to keep an open mind.
An other example is the Altec Lansing 604, The tweeter horn also is in front of the woofer and covers a large part of it and still this is a legendaric driver, that altough it's antique (released in 1944), it still sounds quiet good today, and it still is very popular. The horn changed shape over time (but not that much) but in essense the driver remained the same for his whole lifespan untill the mid 80. And it's still made (more ore less to original specs) by Great Plains Audio...
Will correct a little this: horn is in front. Magnet, coils atc are IN THE BACK of the woofer. Haven't seen this in person, but probably that little "bump" on the back of the big magnet is the small magnet of the tweeter. It is the correct way. Or to be precise - better way.