O 500 C Digital Active Main Monitor

O 500 C
Digital Active
Main Monitor

Main Monitors
Klein + Hummel has developed, with the O 500 C studio monitor,
a comprehensive and innovative approach to the design of large studio monitors. This approach integrates the latest
DSP technology and sets completely new standards for absolutely authentic, uncolored, accurate audio reproduction.
The O 500 C is one of a new class of large reference monitors that employ an integrated digital controller. Digital
signal processing combined with FIR (Finite Impulse Response) filters make it possible to control the amplitude
response and the phase response independently of each other. Other superior factors include the use of the resonancefree
material LRIM, modern, innovative loudspeakers with optimal reproduction quality, high-performance power
amplifiers with high dynamics and a modern enclosure concept.
Active 3-way main monitor
Fully digital frequency switch and system correction via integrated digital controller with FIR filters
Very transparent and analytical reproduction through absolutely linear frequency and phase response from
30 Hz to 20 kHz
Extremely precise dispersion via perfectly fine-tuned drivers for mid- and high-ranges
Higher maximum volume via generous amplification performance (high: 400 W; medium: 230 W; low: 290 W)
Magnetic protection
Same sound character as smaller Klein + Hummel monitors
Optional FIR filters for individual room compensation
10 | 11

Blue VF display shows all settings
Large integrated waveguides
for optimal dispersion pattern
IR remote control
Rotatable high-/low-frequency unit
for horizontal and vertical installation
High-quality outputs for 400 W (low),
230 W (mid) and 290 W (high)
Subwoofer output
connects to O 900
Digital FIR controller
for all parameters

O 500 C Digital Active Main Monitor
Use of unbeatable loudspeakers
Uncompromising bass system
12" cone woofer with cast aluminum basket
Patented construction with rear-ventilated voice coil which
Greatly increases load capacity and
Minimizes power compression
Minimal distortion levels via extremely long excursion
Doubly insulated membrane
Minimal distortion
Self-damping
Insensitive to environment
High effectiveness via especially optimized relationship of outer to inner radius
High resolution mid-range system
3" membrane/voice coil diameter
Minimal distortion via strong driver
Rear-sealed chassis prevents irregularities in the decay spectrum
Precise high-frequency system
Brilliant, low-distortion high-frequency reproduction via powerful 1" titanium fabric dome
Main Monitors
Modern cabinet design
Low-compression bass reproduction via generously proportioned bass reflex ports
Smooth matte enameled baffle design without diffraction edges or fastening elements
Modern design
Numerous mounting and setup possibilities
Also available in different colors
Optimized sound dispersion
Perfect sound dispersion discrepancies in time coherence and non-linearities in the
amplitude response are digitally compensated
Broad horizontal dispersion characteristics
Extended sweet spot, more freedom of movement at the mixer
Narrow vertical dispersion characteristics
Avoids interference from reflection off mixer console
Rotatable drivers for standing and horizontal installation
Excellent dispersion patterns
Very limited interference range via digital frequency filters
Futuristic integrated digital controller
Digital performance at 44.1 and 48 kHz
AD crossover-technology with 130 dB dynamic range
Extremely low distortion via the latest 24 Bit converter technology
Digital input through AES/EBU and S/P-DIF
System correction and phase frequency equalization via individually tuned FIR filters
Numerous corrections available (linear phasing, minimal phasing, etc.)
Pre-emptive limiters:
Peak limiter to avoid transient peaks and regulate power amplifier overloading
Thermo-limiter to protect the power output of the drivers
Large VFD display shows settings
Infrared remote control to program settings
MIDI- and RS232-interfaces
New patented output concept
Very high performance outputs with 400 W for low-, 230 W for mid-, and 290 W for high-range frequencies
Extremely high dynamic: 129 dB/132 dB(A)
Intelligent power supply for minimal power loss
Lowest non-linear distortion (THD+N):
low: < – 110 dB (0.0003 %); mid: < – 100 dB (0.001 %); high < – 90 dB (0.003 %)
12 | 13

Easy, flexible adaptation to location via IIR-EQ’s. In addition to FIR filters, the
O 500 C’s digital controller benefits from an easy-to-install location adapter, which is achieved via conventional IIR
digital technology to allow real-time operation. In installation and performance it resembles the location adapters
which are used on Klein + Hummel’s analog studio monitors and which allow the monitors to be adapted to the most
specific requirements using low, mid and high. The O 500 C also features 10 fully parametric EQ wavebands, which
can be used to further adapt the frequency modulation, in case the location does not provide adapter sufficient
adjustments.
^1
^2
^3
^4
ms
90
80
70
60
0.05 0.2 0.5 1 2 5 10 kHz
50
^1 Low Cut for adjustment of the lower cut-off frequency ^2 Low EQ for compensation of wall-, edge- and cornerpositioning
^3 Mid EQ for compensation of floor- and console-reflections ^4 High EQ for compensation of different
absorbtions of high frequencies in the studio
Individual room adaptation with FIR filters. The O 500 C is designed to be able to
adapt to the individual requirements of any studio. This is possible through our integral FIR-based controller technology.
The frequency and phase of the FIR filters can be adjusted to the room’s acoustics for optimal listening conditions at
the mixer. First, third-octave measurements are taken from a large number of points in the listening area and are averaged
out. The resulting curve takes into account both the speaker’s frequency response and dispersion patterns and the
acoustic response of the room. The interplay of monitor, room and location are then used by the software as a new
preset in non-volatile memory in the integrated controller. During playback, the controller compensates for the room’s
unwanted acoustic imbalances. The result is a significant sound improvement.
This acoustic optimization demands a certain level of experience and equipment. It does, however, represent a costeffective
means of addressing acoustic imbalances.

Frequency response
THD at 100 dB/SPL in 2,1 m total k2 k3
dB
100
90
80
70
60
0.05 0.2 0.5 1 2 5 10 kHz 0.05 0.2 0.5 1 2 5 10 kHz
dB
–10
–20
–30
–40
–50
–60
–70
–80
Group delay linear phase bass-min., mid, high-lin. phase min. phase
Max. SPL in 1 m at 1 % THD
ms
dB
60
110
100
40
90
20
80
0.1 0.2 0.5 1 2 5 10 kHz
0
0.05 0.2 0.5 1 2 5 10 kHz
70
Cumulative spectral decay
0
–5
–10
–15
–20
–25
0,0
+5
0
–5
–10
–15
–20
–25
100 Hz 1,000 Hz 10 kHz
2.3 ms
4.5 ms
6.8 ms
9.1 ms
Horizontal directivity
Vertical directivity
90
90
60
60
30
30
0 degree
0 degree
–30
–30
–60
–60
125 250 500 1,000 2,000 4,000 8,000 16,000
f[Hz]
–90
125 250 500 1,000 2,000 4,000 8,000 16,000
f[Hz]
–90
0 to 3 –3 to 0 – 6 to – 3 – 9 to – 6 – 12 to – 9 – 15 to – 12 – 18 to – 15 – 21 to – 18
Decrease of SPL (dB)
14 | 15