I am using Manger drivers for more than a decade and still find their basic sound quality fascinating. But they are not perfect: dispersion of HF, notch in frequency response at around 800 and 1600 Hz and high distortions at that frequency range. Manger developed new speakers but there is no upgrade of the driver itself for more than 2 decades.
I found Moongel .: RTOM Corporation :. which is used for damping drums and thought to try it on the MSW as they are quite cheap. No effect when used in the periphery of the outside or in the center of inside. But there was some positive effect when the moon gel was applied at the center of the MSW on the frequency response and much more significantly on the distortions levels of the midrange. (filtered at 400HZ)
yellow: MSW alone
dark violet: MSW + Moongel at center
I found Moongel .: RTOM Corporation :. which is used for damping drums and thought to try it on the MSW as they are quite cheap. No effect when used in the periphery of the outside or in the center of inside. But there was some positive effect when the moon gel was applied at the center of the MSW on the frequency response and much more significantly on the distortions levels of the midrange. (filtered at 400HZ)
yellow: MSW alone
dark violet: MSW + Moongel at center
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One thing I forgot to mention: they simply stick to the surface but can easily be removed (no glue required). 1/2 pad had close to the same effect as a hole one. And I would not write about it if it would not sound better - I guess 6% distortion is noticeable.
I expect that other bending wave designs could also profit from this sticky gel.
I expect that other bending wave designs could also profit from this sticky gel.
Very interesting.
Are there no side-effects due to increased mass?
Subjective differences between moongelled vs plain?
Are there no side-effects due to increased mass?
Subjective differences between moongelled vs plain?
The MSW is suspended/fixed in the center with a semisoft material on the inside of the driver (they call that structure Hochton-Reflexionsdämpfer). So adding a mass to the center should have less effect than adding it to the periphery. But I found no effect of the gel pads except when applied to the center. I did not investigate the effects on low frequency as I used a digital filter at 400 Hz. I did not investigate the lateral behavior yet.
It would look better if the Moongel could be attached to the inside between the membrane and the damper but that means to deconstruct the MSW.
Sound wise there is a better tonality of instruments and voices - more natural. Also there is better defined depth of the sound stage.
It would look better if the Moongel could be attached to the inside between the membrane and the damper but that means to deconstruct the MSW.
Sound wise there is a better tonality of instruments and voices - more natural. Also there is better defined depth of the sound stage.
Hello,
did the step response change?
i made a construction which fill the 1,5 kHz dib,
but you need two MSW each, the POSAUNE take a view,
never built but theoretical a best fullrange MSW solution, max. 96 dB
did the step response change?
i made a construction which fill the 1,5 kHz dib,
but you need two MSW each, the POSAUNE take a view,
never built but theoretical a best fullrange MSW solution, max. 96 dB
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The 1,6kHz hole is an acoustic destructive interference that comes because the signal is put in over a high diameter voicecoil. That hole does not create distortion as such.
Here are my results before and after modification. The distortion is THD at quite high volume. It is made up mostly of second. A measure of chaotic behaviour that can also be interpreted as a DC offset.
Here are my results before and after modification. The distortion is THD at quite high volume. It is made up mostly of second. A measure of chaotic behaviour that can also be interpreted as a DC offset.
The driver is 20 years old in an inherited Audio Physic Medea designed by me. It looks like brand new.
with moongel app the step response goes worse ...
"acoustic destructive interference"
no way , where should the delay come from? it must be a helmholtz-type resonance that is coupled to the diaphragm and steals energy ...
btw in nearly every second posts of yours I´m detecting false conclusions , you electronic guys should better stay at your main pro?fashion 😛
greetz - the almighty blechkasten 😉
"acoustic destructive interference"
no way , where should the delay come from? it must be a helmholtz-type resonance that is coupled to the diaphragm and steals energy ...
btw in nearly every second posts of yours I´m detecting false conclusions , you electronic guys should better stay at your main pro?fashion 😛
greetz - the almighty blechkasten 😉
The signal goes in at the large diameer coil and travels quite fast to the internal damper. There the bending wave starts to travel like in a transmission line, higher frequencies first back to the outside. This wave hits the dimension of the voicecoil eventually and interfers. OK, do not call it acoustic, call it mechanical. This was first mentioned by Prof. Heckel in his mathematical analysis of a soft, flat, round, bending plate with a large diameter dynamic voicecoil. Karl-Heinz Fink measured it with a laser interferometer. I talked to Daniela Manger today and she confirmed this. In 1993 in the Audio Lab of the University of Essex we tried to equalize this 1,6kHz dip with a DSP without success again conferming the cancelation effect. This does not create harmonic distortion and is a principle defect that is fortunately not very audible because a narrow dip is much more benign then say a low Q peak. How else can you explain the low distortion of my modifed driver that still has that dip althow at a lower frequency because of mass loading ? Also Mister Möllers Posause does not get rid of that effect although he claims it. I could be persuaded by a measurement i do MYSELF on his construction.
I am a mature, professional speaker designer with 33 years of hands on experience with the Manger driver and its creator.
I am a mature, professional speaker designer with 33 years of hands on experience with the Manger driver and its creator.
"Also Mister Möllers Posaune does not get rid of that effect although he claims it. I could be persuaded by a measurement i do MYSELF on his construction.
I am a mature, professional speaker designer with 33 years of hands on experience with the Manger driver and its creator."
Hallo Joachim vorher nimmst du die Arroganz, ruf mich doch mal an 04101 40 33 59,
schau doch mal die Doppelhörner, bis auf Subfanfare sind alle identisch also auch die Messungen übertragbar,
my experience is 40 years, whow what does that mean, Manger made the measurement of my Basstuba himself and bought the lizenz 1994.
Du hast doch im Frickelfest 2011 schon eine merkwürdige Meinung kundgetan ohne mich zu kennen?
Ich würde doch lieber eine Cooperation suchen als sowas zu schreiben.
I am a mature, professional speaker designer with 33 years of hands on experience with the Manger driver and its creator."
Hallo Joachim vorher nimmst du die Arroganz, ruf mich doch mal an 04101 40 33 59,
schau doch mal die Doppelhörner, bis auf Subfanfare sind alle identisch also auch die Messungen übertragbar,
my experience is 40 years, whow what does that mean, Manger made the measurement of my Basstuba himself and bought the lizenz 1994.
Du hast doch im Frickelfest 2011 schon eine merkwürdige Meinung kundgetan ohne mich zu kennen?
Ich würde doch lieber eine Cooperation suchen als sowas zu schreiben.
I liked the sound of your speakers on the Frickelfest. Actually i listened to them for at least 2 hours and that is much for a design not by me. Loudspeakers are a very personal thing, this is the reason i started to build my own in the first place. This must have come from a thrird party. I can not remember that i talked about you, strange i am though.
How did you get rid of the 1,6kHz hole ?
How did you get rid of the 1,6kHz hole ?
The mechanical energy will travel from the coil both to the center and to the periphery(at all frequencies). Manger claims that the center structure is to dampen high frequency and on the periphery low frequency. The moongel had an effect only at the center. It reduced distortions not only at 1.6kHZ. The waterfall plots with the gel show much faster decay at 400Hz and above 1000Hz but not between 600 and 1000Hz. The improvements frequency wise are reproducible but minor.
If interference with the back wave causes the drops in frequency at 800/1600Hz may be the distortions are independent of the backwave?
If interference with the back wave causes the drops in frequency at 800/1600Hz may be the distortions are independent of the backwave?
The major improvement is in the distortion. With a sine sweep the untreared MSW makes a high pitched noise at some frequencies that is gone after the treatment. I think the improvement is substantial.
Hello , sorry but your analysis "acoustic destructive interference" was simply misleading and raised my interest how you may come to such conclusion . Good to see you got it right at last and people here can learn from your deeper insight .
happy hunting for better sound(reproduction?)
and keep an ear on those room reflections they are the real problem ...
...bye!
ps - the 70mm VC and the disc clamping diameter might be an unlucky combination that generates those unwanted effects ... ever tried an elliptic shape of clamping the wobble dic? ... Manger is a very very old design that is overdue to be completely redone , Daniela seems to be very little inventive ..
How did you apply the Moongel to the Manger? Can you attach a photo of your installation and description of to what size you cut the gel for your experiment?
Thanks.
Thanks.
I have tried the moon gel and it does reduce the distortion slightly at the frequencies mentioned. There seem to be no detrimental effect, so it’s staying.
great to see that someone tried to modify such an expensive fullrange driver and with a good outcome!