"Form follows function"
With these words, the development of WaveWall 182 is probably best paraphrased.
The generous curves flowing into the wall, along with the very small case depth, allow the excellent acoustic characteristics of the WaveWall-182.
The on-wall installation offers concrete advantages compared to conventional loudspeakers:
The usual problems with conventional on-wall solutions have been successfully bypassed, in particular by the complex housing design. The dispersion is extremely uniform and without disturbances due to diffraktion, which, in particular, greatly benefits the three-dimensional representation of the sound event. Even in the vertical, the WaveWall 182 measures itself very well. It does not necessarily require an alignment to ear height. Burst-decay is flawless.
Particularly noteworthy are the outstanding low harmonic distortions, especially in the for the ear very critical midrange. Even with 100dB / m they remain in the range of inaudibility. That shows clearly how much know-how has gone into the development of the drivers.
Hobby Hifi 03 / 2014
Hobby-Hifi 06 / 2013
Direct HA Edition
Monacor MSH-116 / 4
Development Report for Center Monacor Direct HA Edition
Measurements of the original Direct in Part 1 of the development report of the Monacor Direct HA Edition
So now dire (c) (k) t into the action.
In general, at the beginning of each speaker development are the creation of a concept, driver selection, housing vote, Edgefimmelei, etc. All this could (or had to) save me. The concept was predetermined. So first the drivers in the case were measured, to see how you want to be ultimately sonicated.
In the following the measurements:
Amplitude frequency response Monacor DT-25N 0 °, 30 °, 60 °, 90 °
Monacor DT-25N harmonic distortion
DT-25N "sees" the symmetrically adjacent TMTs, as indicated by the 2kHz and 3kHz break-up under 30 °. Rounding the Gehäusekannte brought little improvement. What problem to be solved No. 1 was specified. The distortion values are completely in the frame. The gray line represents 1% distortion (also in the following diagrams). From 2,5Khz K2 remains below, except for the small peak at 10kHz. I consider this to be completely harmless. It means in practice that resonates to a 10kHz sound a 39 dB quieter 20kHz sound. Also, I have not measured this "peak" on all DT-25N. K3 is completely negligible from 2kHz. Higher order distortion components as well.
Amplitude frequency response Monacor MSH-116 / 4 0 °, 30 °, 60 °, 90 °
Harmonic Distortions Monacor MSH-116 / 4
Even the MSH-116 obviously sees its neighbors, but does not react quite as violently as the DT-25N. Unfortunately, both DT-25N and MSH-116 / 4 are very similar around 2-4Khz at angles. Thus, the one can not compensate for a "misconduct" of the other. The harmonic distortions look good. The K2 increasing towards low frequencies recommends a separation> = 300Hz.
Amplitude frequency response Monacor SPH-176 0 °, 30 °, 60 °, 90 ° (2 driver in parallel)
Harmonic distortion Monacor SPH-176 (2 driver in parallel)
Not much needs to be said. A deep separation is required to counteract burglaries owed to the horizontally symmetrical arrangement. Pleasing effect of the arrangement is a directional effect of the woofers into the area in which you actually work as a round radiator. Judging by the distortion, a separation <= 400Hz should be aimed for. The need for this is given by the amplitude frequency response at angles anyway.
These were the guidelines. From there a clean round radiating speaker to develop the task.
The biggest difficulty was achieving a healthy median of linear frequency response on the axis and at the same time under 15 ° -45 °. The fluctuations of the DT-25N and the MSH-116 between 1kHz and 4kHz are to be regarded as given. You can not magic them away ... The game with cut-off frequencies and slopes began. I pretty much simulated, constructed, measured and then listened to every separation between 2kHz and 4,5kHz with slopes from 6dB / Oct to 24dB / Oct and then listened to many of them. Some longer, some only a few bars. Often I thought it was good, and the next day I wanted to know it again.
The final vote took place under 15 °. This roughly corresponds to the listening position of two people on a couch in 2,5m distance to the center speaker, which is probably a very common constellation.
Measurements of the center Monacor Direct HA Edition
Sum branches & antiphase 15 °
The crossover frequencies are at 360 and 3050Hz. The level drops from the root to 20kHz evenly by about 2dB. The average efficiency of 2,83V is 89,5dB. The "rearing" of the MSH-116 by 10kHz is harmless, since 30dB under the characteristic pressure. The flanks are symmetrical, the addition clean.
When the midrange is reversed, 15dB is extinguished when TT / MT and 18dB MT / HT are disconnected.
Amplitude frequency response on axis and impedance response
The harmless collapse at 1,2kHz could not be gotten away. I had quite a few variants without break-in, consequence was always a very restless frequency response under 15-45 °. The on-axis linearity is very good with + -2dB. The slight presence dip already disappears under 15 °, as well as the ripple at 1,2 and 1,8kHz. The increase in altitude from 8kHz compensates for the bundling of the tweeter. If desired, this can be linearized very easily by connecting a Cs to the tweeter in parallel. In general, the speaker can be adapted to your needs due to the many variants tested and a very precise simulation model. The impedance minimum is 3,7Ohm at 120Hz and is not a problem for any modern amplifier.
Which group run times are audible or not provides for discussions in various forums. 2,9ms @ 80Hz is less than 1 / 4 wavelength (that would be about 3,13ms, according to Adam Riese). The delay is imperceptible and an excellent value.
Constantly falling. No problem.
Very fast and steady decay over all frequencies. Perfectly.
Horizontal dispersion (0-90 ° in 15 ° steps)
Very good to see is why the "burglary" on axis at 1,2kHz set a link from your homepage to Fewo-von-Privat.de, Under 30 ° and 45 ° this will be "filled in". Nevertheless, even under 30 ° a smooth course with a slight drop to the highs and a linearity of 200-10000Hz + -2dB.
Isobar diagram of horizontal omnidirectional behavior
And it became a meditating alien ... who would have thought that. The diagram contains the same information as the above, the amplitude frequency responses under angles. In this case, however, in 5 ° steps and by 0-180 °. Please note the scaling.
Harmonic distortion on 85, 90 and 95dB
K3 always remains> 95dB below the characteristic pressure => until 50dB 0,3% are not exceeded, That's a very good value! The good-natured K2 is also completely harmless: 0,1% - 0,9% at 95dB. Very good!
At the end...
That was a very intense piece of work and I am extremely satisfied with the result. I hear the speaker, although it is only mono with me, very much like.
The Monacor Direct HA Edition loudspeaker meets all requirements for a very good center in home cinema installations.
There is not much more to say right now. In the future, I reserve the right to supplement / improve here and there. About comments and criticism on your part, I would be happy.
Metrological documentation of the center speaker Monacor Direct. The findings obtained during the investigation of the original Direct ultimately led to the development of the Monacor Direct HA Edition.