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Magnat Magnasphere Nova Speaker System Review

Magnat Magnasphere Nova
Magnat Magnasphere Nova BRON

Magnat, a prominent West German loudspeaker manufacturer, is introducing a novel four-way, three-piece speaker system that is claimed to be the first speaker to achieve true omnidirectional sound dispersion. The system supplied to us for test was a preproduction model, as the speaker is not scheduled for release until later this year.

The Magnasphere Nova consists of two satellite speakers and a powered subwoofer module. The subwoofer, like similar products in its external appearance, is approximately cubical and has a glossy black piano finish. Its output emerges from slots about 2 inches high and 20 inches long near floor level on the front and rear of the enclosure.

The satellites, however, are unique in appearance and design. Each consists of three black, perfo-rated-metal spheres stacked vertically on a slender black-steel column. Each sphere contains a pair of magnetic drivers mounted back-to-back and radiating in opposite directions. Since each driver pair operates in phase, the radiation pattern is approximately the same in all directions except in the plane of the sphere’s vertical “equator,” where the drivers are joined.

The bottom sphere of each satellite, the “woofer,” contains two 4-inch polypropylene-dome radiators that operate between 100 and 1,400 Hz. Each dome, constructed of two different thicknesses of polypropylene and mounted in a cutout in a plastic sphere slightly less than 8 inches in diameter, is driven at its 2-1/4-inch diameter by an inner “cone” that has a smaller voice coil at its apex.

The middle sphere, which radiates from 1,400 to 3,400 Hz, is essentially a smaller version of the woofer sphere. It contains two 2-inch soft-metal-dome radiators mounted back-to-back within a 4-inch spherical case, which in turn is surrounded by the perforated-metal cage. Immediately above it is the tweeter, with a pair of 1-inch drivers in a 2-1/2-inch cage (all these dimensions are approximate).

Passive crossover networks for the satellite drivers are located within their spherical enclosures, which are joined by eight-pin DIN connectors. A separate control box contains an active electronic crossover circuit, with a slope of 24 dB per octave, that excludes the low-bass frequencies from the satellites, supplying them to the subwoofer module through a cable and DIN plugs. The controller has front-panel adjustments for setting the subwoofer’s output level and the low-bass crossover frequency (either 80, 100, or 120 Hz).

An unusual feature of the Magnat system is its time-delay correction. Any three-piece system such as the Magnasphere Nova is very likely to have large time differences between the outputs of its subwoofer and satellites. In part, this results from the placement of these components in the listening room, where they are often many feet apart, and in part from the inherently greater delay in the output of a subwoofer compared with that of a midrange or high-frequency driver. The audible significance, if any, of these time differences has not been established, but the Magnasphere Nova provides a way for the user to compensate for them, if only approximately.

The signals supplied to the satellites are routed through a high-pass Bessel filter whose delay can be adjusted for 0, 32, or 64 milliseconds (ms) by a switch on the control unit. Since typical delay differences in a three-piece system like the Nova will fall in that range, presumably a user could reduce the differences substantially by delaying the satellite speakers’ output by 32 or 64 ms.

The Magnasphere Nova subwoofer contains four long-throw drivers, each with a cone diameter of 7-2/5 inches. They are mounted in opposing pairs on a board that divides the inside of the cabinet horizontally. Each pair is driven by the signal from one stereo channel, although the acoustic outputs of all four drivers are effectively combined at the cabinet’s ports. Magnat describes the subwoofer as having a “compound principle” of operation. Apparently each opposing pair of drivers operates in “push-pull” mode, with their cones moving in the same direction, instead of in opposition as in the satellites. The subwoofer’s amplifier, built into the enclosure, is rated to deliver 180 watts per channel continuously, or 500 watts peak output, with less than 0.05 percent distortion.

The top of the tweeter sphere is about 47 inches from the floor, the bottom of the woofer sphere about 30 inches. The stands, about 1-5/8 inches in diameter, have black cast-iron bases. Each complete satellite weighs about 28 pounds. The subwoofer module is about 21 inches wide and high, and 18 inches deep. Although its weight was not specified, we can testify that it is very heavy!

The control unit is a black-finished metal cabinet that measures 16-3/4 inches wide, 11 inches deep, and 3-3/8 inches high. Its front panel contains a power switch and a small button that causes a motor to open and close the lower half of the panel, which covers the other controls. The panel also has a pair of overload lights to warn of excessive signal levels. Price: $5,500 (estimated) for the system.

Lab Tests

Some details of the Magnasphere Nova system, especially the control unit and its specific adjustment ranges, might be changed in the final production models. Since the radiators used in the satellites have been in the Magnat product line for some time, however, they can be expected to remain as described.

We placed the satellites about 8 feet apart and 4 feet from the wall behind them. The subwoofer was located approximately on the same line as the satellites and midway between them. We set the subwoofer output level by ear for the best possible bass response without excessive boominess on vocal sounds, and the 80-hz crossover setting was used for most listening and measurements. We tried the other settings as well, but the lowest of the three frequencies generally produced the best results.

Our frequency-response measurements were made in the usual way, plotting room-response curves for both satellites on the same chart and averaging them to smooth out room standing-wave effects. We measured the subwoofer’s response with each of the crossover settings, placing the microphone at one of the output slots. Bass distortion was measured at the same point, using the 80-Hz crossover setting.

We measured the impedance of a satellite unit, which is the only part of the Magnasphere Nova that is actually driven by the user’s regular system power amplifier, over the full audio frequency range. The system’s sensitivity was measured at a 1-meter distance, with only one satellite operating, using 2.83 volts of pink-noise input. Since there is no fixed relationship between the signal input level and the subwoofer’s acoustic output (their relative levels are set by ear), we measured the drive signal needed to produce a 90-dB sound-pressure level (SPL) at a 1-meter distance from the subwoofer slot at 50 Hz (on the flat portion of the subwoofer’s frequency response) and then maintained that same input level from 100 Hz downward when measuring bass distortion.

Our quasi-anechoic FFT response measurements with the IQS signal-analysis system were made 1 meter from a satellite. With the microphone close to each of the spheres, we also measured their individual frequency response on the forward axis and at 45 and 90 degrees off-axis (the latter angle is close to the solid band that unites each pair of hemispheres). Plotting the axial and off-axis response curves on the same printout enabled us to assess the actual directivity of each section of the satellite speaker. In addition to our usual group-delay measurements, applied to a complete satellite array, we made a group-delay measurement on the output of the subwoofer alone.

The satellites’ combined room response was very uniform, ±3 dB from 200 to 20,000 Hz, indicating a relatively flat acoustic power-output characteristic. Below 200 or 300 Hz the response became irregular because of room reflections. The close-miked subwoofer response was flat within ± 2 dB from 25 to 80 Hz using the 80-Hz crossover setting; the upper limit extended to 110 and 140 Hz with the 100- and 120-Hz settings, respectively. From 30 to 72 Hz, the subwoofer’s output varied only ± 1 dB.

Splicing the Nova system’s bass and room-response curves was not as easy as it is for most conventional single-cabinet speaker systems. The reference level of the bass curve could be placed almost anywhere relative to the room-response level, and the room’s standing-wave effects eliminated the usual clues to the relationship between the two. We finally joined the curves with the flat region of the subwoofer response at the same level as the smoothed satellite room response, which left the region from 100 to 200 Hz undefined. Since this frequency range is strongly affected by speaker placement and room dimensions, our choice was not unreasonable. The other parts of the curve give a fair indication of what the Magnasphere Nova system itself is capable of.

The composite response, which had only a few minor irregularities, varied ± 3 dB from 23 to 20,000 Hz. The bass distortion was between 2 and 3 percent from 25 to 100 Hz, climbing to 8.5 percent at 20 Hz. The distortion consisted entirely of second and third harmonics.

The impedance of a satellite, using the 100-Hz crossover, varied between 3.7 and 7 ohms over the range from 200 to 20,000 Hz (the nominal system rating is 4 ohms). The impedance rose smoothly below 200 Hz, to about 60 ohms at 20 Hz, reflecting the isolation provided by the system’s crossover network.

The system’s sensitivity appeared to be rather low, with each satellite producing only 80 dB spl at 1 meter with a drive signal of 2.83 volts of pink noise. This figure does not include, however, the considerable contribution of the subwoofer at frequencies below 100 Hz. In actual use, the system did not require an unusual amount of drive power even at very high levels.

The fft measurements were consistent with our other results. Since they extended beyond our usual 20,000-hz measurement limit, they confirmed that the satellites’ high-frequency response was virtually flat up to about 27,000 Hz. One of the more interesting fft measurements was the group-delay response to the subwoofer, which averaged about 30 milliseconds from 35 to 95 Hz and increased to 70 ms at 20 Hz. This suggests that the optional delay compensation in the Nova’s system controller could, in theory, correct for much of the difference between the subwoofer’s delay and the typical delay of less than 0.5 ms across the rest of the audio range that we measured from the satellite output.

The fft measurements also proved that the spherical radiators are not really omnidirectional, although their effective dispersion is wide enough to give them many of the subjective qualities of an omnidirectional radiator. A close-miked measurement of the tweeter sphere at angles of 0 and 45 degrees off its forward axis showed that the two response curves differed by 3 to 6 dB over most of the tweeter’s operating range. Although this is good dispersion, the response at 90 degrees off the forward axis was down more than 20 dB over most of the range. As would be expected, the midrange radiator was better, with less than 3 dB separating the axial and 45-degree curves over its full operating range. Still, the midrange output at 90 degrees off-axis was typically 18 to 20 dB below the axial level. The woofer sphere showed virtually no response change over the first 45 degrees, but at 90 degrees it was a uniform 12 dB down over most of that driver’s operating range.

Comments

The Magnasphere Nova system was a very “listenable” speaker. The sound from the satellites seemed to float in the air, with no clues to its origin as long as we were a few feet away from the speakers. It not only filled the space between them but extended behind and above them as well.

We were unable to hear any difference in the sound as a result of switching the delay compensation between 0 and 64 milliseconds, but there is little evidence to show that bass delays in that range are audible. While this feature looks promising in principle, it may be of little practical value.

The subwoofer, of course, cannot be located by ear, although it is certainly obvious to the eye. Too much subwoofer output can make some programs bottom-heavy, and we chose what seemed to be a reasonable level for our listening tests, setting the bass control at less than half of its maximum rotation. Even this middling level produced a solid, almost tactile deep-bass output with suitable program material.

We soon found that listening to the Magnasphere Nova tends to distract one from trying to dissect and analyze its sound output. That is a characteristic of most very good speakers, and the Nova is unequivocally one of the better-sounding ones we have heard.

Our only clear disagreement with the claims made for the Magnasphere Nova concerns its supposed “omnidirectionality.” The satellites are really sets of three dipole radiators, with virtually no radiation to the sides and equal outputs front and rear. They have the audible qualities of a good dipole and are much more compact than most. Whether you find them attractive as home furnishings is a matter of personal taste. And they are certainly expensive. But in the final analysis, it is the sound of a speaker that justifies its cost, and Magnat’s Magnasphere Nova system passes that test beautifully.

Humidor

High-end 2-way shelf-top speaker with genuine cedar wood veneer

Stylish products deserve stylish packaging. We took this basic principle very much to heart when developing the Magnat Humidor: The high-end 2-way shelf-top speaker combines the highest quality components, balanced acoustic tuning and unique design in a harmonious way. Its stylish body made of sturdy MDF wood is covered with a two-tone genuine cedar wood veneer. This means that the Humidor clearly enriches very room, not only acoustically but also visually.

Serienslider_Humidor-3 (1)COMPACT FORMAT, STRONG SOUND

The Humidor has a markedly compact shelf-top speaker format: With dimensions of just 140 x 245 x 258 mm, it is at home in just about any living room surroundings. The compact design is quickly forgotten, however, as soon as the Humidor starts performing: The precise treble ranges, clearly intelligible mid-range as well as the precise, strong bass foundation show impressively what modern technology and experience can achieve. To this end, the Humidor has opted for a high-quality aluminium-ceramic subwoofer. This high-end- material combines optimum rigidity with high internal damping. The Magnat Airflex bass reflex port provides for additional bass without any flow noise. Used as the tweeter is a silk dome with a particularly wide surround to improve the dispersion characteristics over 20 kHz. Both the tweeter and the subwoofer are driven by extremely powerful magnet systems. Together, the chassis duo ensures the highest sound precision and convincing dynamics over the entire frequency range.

Serienslider_Humidor-2.jpg

HIGHEST QUALITY COMPONENTS FOR INCOMPARABLE MAGNAT SOUND

The high-quality design and construction method is continued in the Humidor down to the smallest detail. The crossover was phase and amplitude optimized in the complex development process and fitted exclusively with selected components. For example, the coil of the deep bass branch is of a low impedance design in order to achieve the absolute maximum bass and efficiency. All of the internal wiring is of a large gauge to guarantee low-loss transmission of the audio signal. The high-end connecting terminal expertly rounds of the Humidor with its solid metal support plate and the gold-plated, acrylic varnished screw terminals.

STYLISH ENCLOSURE FOR HIGH-END TECHNOLOGY

The Humidor not only produces outstanding sound, it is also very attractive visually. The sturdy MDF enclosure ensures resonance-free reproduction and is covered with a stylish, two-tone genuine cedar wood veneer. Added to this is an attractive solid-metal sound guide for both speaker chassis as well as an inlaid solid-metal logo on the top of the enclosure. All of the metal elements, including the connecting terminal, are presented in a fine champagne shade to match harmoniously with the wood colors.

PERFECT SOUND THANKS TO COMPUTER-OPTIMIZED MEASUREMENTS USING THE KLIPPEL SYSTEM

Responsible for the perfect sound of the Humidor are the high-quality components as well as the precise coordination and tuning. The shelf-top speaker has undergone an elaborately complex and time-consuming development process. During this, all the components were adjusted and improved in a large number of individual steps, also with the help of the high-precision Klippel laser measuring system. With the help of this, the subwoofer, in particular, was optimized to such an extent that it extracts an impressive bass foundation from the compact enclosure with high level stability.

This meticulous development, the decades of experience gathered by our engineers and the high-quality components have combined to create an exceptional loudspeaker in the form of the Magnat Humidor: High-end in the smallest of spaces with a stylish wood design.

Humidor
High-end 2-way shelf-top speaker
with genuine cedar wood veneer

Principle
High-End-Bookshelf Speaker
Equipment
4.5“ Woofer-midrange
25 mm dome tweeter
Power Handling (RMS/Max.)
75 / 150 watts
Frequency Response
34 – 50000 Hz
Sensitivity (2.8V/1m)
90 dB
Dimensions (WxHxD)
140 x 245 x 258 mm

RIAA Recording Curve

De RIAA Recording Curve is een door de RIAA gestandaardiseerde opnametechniek en een bijhorende afspeeltechniek voor vinylplaten, zoals lp’s en singles. In samenwerking met geluidstechnici van andere instituten en bedrijven heeft de RIAA voor de vinylplaten in 1955 de definitieve opname frequentiekarakteristiek, de RIAA Recording Curve, ook wel de RIAA Equalization Curve genoemd, vastgelegd. Dit was nodig, omdat er destijds nog geen algemeen aanvaarde standaard was om een gelijkmatige frequentiekarakteristiek te realiseren bij de opname en weergave van vinylplaten. Tevens treden er bij de productie van vinylplaten fysieke begrenzingen in het medium, de stof vinyl, op.

De RIAA Reproduction curve voor het afspelen van vinylplaten.

Om lage tonen met dezelfde geluidssterkte vast te leggen als hoge tonen, zouden zeer brede groeven in het vinyl nodig zijn. Daarbij komt dat hoge tonen meer akoestische energie afgeven dan lage tonen. Om beide effecten te compenseren werd de zogenaamde RIAA Curve vastgesteld. Deze curve zorgt ervoor dat bij de opname de lage tonen met een lager volume werden opgenomen dan de hoge tonen, waardoor afspeelbare groeven mogelijk zijn. Bij het afspelen worden de hoge tonen afgezwakt en de lage tonen weer opgehaald, door middel van de RIAA Reproduction Curve (ook wel RIAA weergave karakteristiek) in de pickup-voorversterker. Deze RIAA Reproduction Curve is het spiegelbeeld van de RIAA Recording Curve, waarbij gespiegeld is langs de verticale as van de grafiek. Hierdoor wordt bewerkstelligd dat bij het afspelen van muziek een zo’n vlak mogelijke frequentiekarakteristiek wordt gehandhaafd.

Toch zijn er ook nadelen van deze opnamecorrectie vast te stellen. Weliswaar resulteert dit in een lage ruisfactor bij het afspelen van platen (ruis is vooral hoorbaar in hogere frequenties van het geluidsspectrum), maar daarnaast moeten hoge eisen aan de draaitafel worden gesteld om de productie van gestommel tegen te gaan, ook wel rumble genaamd. Deze rumble is hoorbaar als lage en sub-lage tonen en wordt door de weergavekarakteristiek bij het afspelen extra versterkt weergegeven.

Gerenommeerde platenspelers of draaitafels hebben een zeer laag rumble niveau en voldoen daarmee aan de eisen voor Hi-Fi apparaten.

CD’s hebben dit type frequentiecorrectie niet nodig. CD persingen in de jaren 80 van LP opnames bevatte echter per ongeluk de RIAA Recording Curve. Hierdoor klonken deze CD’s erg schel en bevatten de opnames zeer weinig laag. Dit effect heeft de beoordeling van de kwaliteit van CD’s enige tijd beïnvloed.

De formule voor de originele RIAA Curve luidt:

{\displaystyle N=10\log _{10}(1+4\pi ^{2}f^{2}{t_{1}}^{2})}N=10\log _{{10}}(1+4\pi ^{{2}}f^{{2}}{t_{{1}}}^{{2}})
{\displaystyle -10\log _{10}\left(1+{\frac {1}{4\pi ^{2}f^{2}{t_{2}}^{2}}}\right)}-10\log _{{10}}\left(1+{\frac  {1}{4\pi ^{{2}}f^{{2}}{t_{{2}}}^{{2}}}}\right)
{\displaystyle +10\log _{10}\left(1+{\frac {1}{4\pi ^{2}f^{2}{t_{3}}^{2}}}\right)}+10\log _{{10}}\left(1+{\frac  {1}{4\pi ^{{2}}f^{{2}}{t_{{3}}}^{{2}}}}\right)
waarin:

N = level in dB
t1= hoge tonen tijdconstante, 75μs
t2 = midden tonen tijdconstante, 318μs
t3 = lage tonen tijdconstante, 3180μs

De drie kantelfrequenties kunnen nu eenvoudig worden berekend met de formule:

{\displaystyle f_{k}={\sqrt {\frac {1}{4\pi ^{2}{t_{n}}^{2}}}}}f_{{k}}={\sqrt  {{\frac  {1}{4\pi ^{{2}}{t_{{n}}}^{{2}}}}}}
waarin:

fk = kantelfrequentie in Hertz.
tn = de tijdconstante in seconden.

Invullen van de drie tijdconstantes geeft de volgende kantelfrequenties:

t1 = 75μs geeft 2.1kHz.
t2 = 318μs geeft 500Hz.
t3 = 3180μs geeft 50Hz.

In de afgebeelde grafiek zijn deze kantelfrequenties goed zichtbaar, als rekening wordt gehouden met de logaritmische schaalverdeling.

BRON

YAMAHA CD

1982

The first CD player designed with our own aesthetics of sound and appearance.

CD-1

open

Yamaha released its first CD player in 1982, just after the birth of the CD. Its groundbreaking features included a slide-out disc loading drive mechanism rather than tray-loading, component-style front controls, a mirror that let you see the recorded side of the spinning disc, and an LED bar graph that showed the approximate position of the pickup. For an era familiar only with the analog record, it was probably a natural assumption that the disc and pickup were meant to be seen during play. The choices for a main device were still limited, but this unit straightforwardly emphasized the sonic difference with linear 16-bit twin D/A converters and separate power supplies for the digital and analog elements. It was also technically unique, with a custom IC developed in-house at the heart of its control system. More than 30 years later, the attention to every detail and clean styling of the Yamaha aesthetic have not lost their luster.

close

1983

The ultimate version of the CD-1 series, which changed the preconception that “CD sound has no personality”

CD-1a

open

1983

Our original best-selling CD player that broke the $499 USD barrier for the first time.

CD-X1

open

1985

A second generation high-grade unit that used our unique VMA method to focus on mechanical vibrations during CD playback.

CD-2000 / CD-2000W

open

1986

Featuring the world’s first 18-bit precision D/A conversion system, this product ignited the high bit arms race.

CDX-2200

open

1987

A special release bringing together all the values of separate units in one model to honor the 100th anniversary of Yamaha.

CDX-10000

open

1987

Reached an incredible 118 dB S/N ratio thanks to eight times oversampling.

CDX-2000

open

1988

The ultimate in high-bit digital, with eight fs, 22-bit operation and a four DAC configuration.

CDX-2020

open

1991

Embodying the GT concept, a superlative CD player that took audio back to its origins.

GT-CD1

New Omega 380

New Omega 380

 omega380_sub_beauty1

High-end active subwoofer for genuine home cinema enthusiastsThe Omega Sub from Magnat has been designed as a real all-rounder and is perfect for a variety of applications and combinations. The tremendously powerful subwoofer, with its generously dimensioned 38 cm chassis, is an ideal partner for fully-fledged floorstanding speakers or compact satellite speakers and it provides a voluminous foundation for acoustic events in the deep bass range, which is of significant importance for the home cinema sector.

Premium chassis and high-power amplifier for optimum performance

omega380_sub_beauty2
An exclusive feature of the Omega Sub 380 is naturally its 380 mm high-power long-throw chassis. The coated and hardened paper cone guarantees a profound, yet faithful reproduction of the lowest frequencies. This high level of precision ensures structures are clearly discernible in the bass range without a trace of reverberation. The chassis is equipped with a Klippel-optimized magnet system, while the ventilated high-performance voice coil ensures maximum operational reliability.
The integrated amplifier generates a maximum output power of 300 watts. The sub is naturally also provided with controllers for the volume, crossover frequency and phase response. A front panel with LED status display facilitates operation. An automatic standby function, which has a very low power consumption, is also available. The supplied remote control, which can be used to switch the subwoofer on and off as well as adjust the volume, is something of a rarity.

Bass reflex coordination and down-firing principle define the housing concept

omega380_sub_beauty1
The Omega 380 subwoofer is accommodated in a sturdy MDF housing with elaborate bracing and operates according to the down-firing principle. The distance to the base plate has been meticulously calculated and this, in combination with the generously dimensioned airflex ports with their low flow resistance, not only results in a particularly deep and precise bass range, but also an elimination of flow noise and unwanted frequency ranges.

Description
Value
Principle
Powered bassreflex subwoofer, down-fire
Equipment
380 mm Woofer
Output power (RMS/Max.)
150 / 300 watts
Frequency Response
17 – 200 Hz
Crossover Frequencies
50 – 150 Hz adjustable
Phase
switchable 0°/180°
Dimensions (WxHxD)
458 x 545 x 620 mm
Weight
30,5 kg
Cabinet surface
Black textured veneer