EAW NT29 User Manual

Eastern Acoustic Works One Main Street Whitinsville, MA 01588 tel [phone] fax [phone] www.eaw.com

EAW products are continually improved. All specifications are therefore subject to change without notice. Part Number: RD0302 (A) NT29 SPEC December 2005

NT29 Specifications group · J

Features

•

2-way, self-powered, bi-amplified loudspeaker

• New digital filters eliminate transient smear and horn “honk”

• Rugged, Baltic birch plywood enclosure

• Extremely high output-to-weight ratio

• Symmetrical shape allows mirror-image stage monitoring

Description

The NT Series are self-powered, bi-amplified loudspeakers.
Designed for the demands of professional use, they can be the main
PA or stage monitors in both portable and installed applications,
including: theatres, corporate AV, clubs, houses of worship, schools,
auditoriums, and band gigs.

Powerful, field-replaceable, amplifier modules use proven, high
efficiency technology. Adding only about 9 lb (4 kg) per loudspeaker,
these dependable amplifiers not only provide lots of power, their
design affords superior sonic performance.

NT’s digital signal processing sets it apart. EAW invented new, digital
filter algorithms, called Gunness Focusing™, to generate precise,
complex, filter responses. These filters provide the linear phase
response needed for transient accuracy while eliminating coloration
from internal phase plug and horn mouth reflections. Digital limiting,
specifically tailored to driver limitations and to maintain sound quality,
provides more usable output while reducing the risk of driver
damage. EAW’s new processing results in a powerful, horn-loaded
loudspeaker that has the natural, open, detailed reproduction of the
best direct radiating designs.

NT's mechanical performance received equal attention, including
many weight-saving design elements, while maintaining the
traditional, rugged, dependability of EAW loudspeakers.

The companion, self-powered NTS22 subwoofer is engineered to
extend the low frequency response and output capabilities of NT full­range loudspeakers. Its integral low pass filter provides an optimized,
acoustic crossover between the full-range and subwoofer.

Six year loudspeaker warranty. Two year electronics warranty.

2-WAY SELF-POWERED, 90° x 45°

See NOTES TABULAR DATAfor details

CONFIGURATION

Subsystem

Transducer Loading

LF 1x 12 in, 3 in voice coil Sealed

cone driver with
neodymium Orbital Magnet Array™

HF 1x 1.4 in exit, 3 in voice coil Horn-loaded

compression driver with
neodymium Orbital Magnet Array™

Operating Mode

Amplifier Channels Signal Processing

Bi-amp LF, HF DSP w/2-way filters

ACOUSTICAL PERFORMANCE

1

Operating Range 60 Hz to 20 kHz
Nominal Beamwidth

Horz 90°

Vert 45°

Axial Output Limit (whole space SPL)

Average Peak

Calculated LF/HF 127 dB 133 dB

ELECTRICAL PERFORMANCE

Input

Type Electronically balanced

Sensitivity 2.5 V / 10 dBu at Limit

2

6.2 V / 18 dBu at Clip

2

Impedance 20 k ohm (balanced to chassis), 10 k ohm (unbalanced)

Wiring Pin 1: chassis, Pin 2: signal +, Pin 3: signal -

DSP(50 Mflop 32 bit Sharc)

Encoding 24 Bit / 48 kHz

Filters Proprietary

Latency 2.15 ms

Amplifier

LF HF

Type Modified Class D Modified Class D

Maximum Output 63 V, 1000 W @ 4 ohm 45 V, 500 W @ 4 ohm

THD + noise <0.3 % <0.1 %

Dynamic Range >105 dB >102 dB

Driver Protection Integral DSP limiting

AC Mains (Nominal)

Connector Neutrik PowerCon

®

115 V 230 V

Input 100 V to 120 V

3

220 V to 240 V

3

Frequency 50 Hz to 60 Hz 50 Hz to 60 Hz

Current: Idle 0.25 A 0.15 A

In Rush 0.9 A 0.6 A

Output Limit 1.6 A

2

1.0 A

2

Fuse Rating 10 A 6.3 A

CONTROLS

HPF (crossover) 55 Hz / 110 Hz

Mode Normal / Coupled

INDICATORS (LED)

Signal Present Green

Limiter Active Yellow

Clip Red

Amplifier Status Green (Normal), Red ( Fault)

ORDERING DATA

Description Part Number

NT29 2-Way Self-powered Black 115 V 0015146
NT29 2-Way Self-powered Black 230 V 0016280

Optional Accessories

Fly Clip with ring 0001386

COMPLIANCE

CE EN 60065:2002, EN 55103-1:1997, EN 55103-2:1997

EN55103-1, EN55103-2, EN60065
CSA CAN/CSA 60065-03, UL Std No. 60065-03
FCC Part 15

1 Specified performance is with the fixed, integral, signal processing. Performance will vary with any external signal processing.
2 Input signal: pink noise, 20 Hz to 20 kHz, 6 dB crest factor.
3 Input ac volt ranges as specified to meet Compliances. Maximum ranges: 115 V = 90 V to 132.5 V; 230 V = 190 V to 265 V.

Eastern Acoustic Works One Main Street Whitinsville, MA 01588 tel [phone] fax [phone] www.eaw.com

EAW products are continually improved. All specifications are therefore subject to change without notice. Part Number: RD0302 (A) NT29 SPEC December 2005

NT29 Specifications group · J

ENCLOSURE

Material Baltic birch plywood, aluminum back panels, Santoprene™ bumpers

Finish Wear resistant textured black paint

Grille Powder-coated perforated steel

NOTE: This drawing has been reduced. Do not scale.

EASTERN ACOUSTIC W ORKS

L

C

ACCESS PANEL

1.85

[47.0]

L

C

BACK

POWER AMPLIFIER

5/16-18 T-NUT FOR OMNI MOUNT SERIES 120.0

1. SYMBOL INDICATES CENTER OF BALANCE.

2. SYMBOL INDICATES MOUNTING POINT,

3. WEIGHT APPROX. 53 lb [24.0 kg]

4. SHIPPING WEIGHT APPROX. 59 lb [26.8 kg]

NOTES:

PRODUCTION

VIEW A-A

L

C

11.00

[279.4]

4.50

[114.2]

NT29

14.88

[378.0]

2X 8.43

[2X 214.1]

6.75

[171.5]

3.28

[83.3]

A

L

C

6.10

[154.9]

22.60

[574.0]

HANDLE

3X FLY TRACK

5.63

[143.0]

4.78

RIGHT SIDE

[121.4]

TO BOTH SIDES

DIMENSIONS APPLY

3.44

[87.4]

7.75

A

L

C

[196.9]

90°

L

TOP

15.18

[385.6]

GRILLE PARTIALLY SHOWN

C

FRONT

6.50

TOP HAT

[165.1]

6.88

BOTTOM

[174.6]

Eastern Acoustic Works One Main Street Whitinsville, MA 01588 tel [phone] fax [phone] www.eaw.com

EAW products are continually improved. All specifications are therefore subject to change without notice. Part Number: RD0302 (A) NT29 SPEC December 2005

NT29 Specifications group · J

PERFORMANCE DATA

See NOTES GRAPHIC DATA for details

Frequency Response: Processed Bi-amplified

Complete = blue

SPL (dB)

10

0

-10

-20

-30

-40

-50
10 100 1000 20000

Frequency (Hz)

Degrees

180

90

0

-90

-180
10 100 1000 20000

Frequency (Hz)

Phase Linearity

Complete = blue

100 1000 20000

Frequency (Hz)

Beamwidth (-6 dB SPL Points)

Horizontal = orange Vertical = black

400

100

10

1

Degrees

Directivity (DI, Q)

Complete = blue

20

10

1

100 1000 20000

Frequency (Hz)

100

10

0

DI (dB)

Q

Eastern Acoustic Works One Main Street Whitinsville, MA 01588 tel [phone] fax [phone] www.eaw.com

EAW products are continually improved. All specifications are therefore subject to change without notice. Part Number: RD0302 (A) NT29 SPEC December 2005

NT29 Specifications group · J

0

-45

-90

-135

180

135

90

45

100 Hz

125 Hz

160 Hz

200 Hz

0

-45

-90

-135

180

135

90

45

250 Hz

315 Hz

400 Hz

500 Hz

0

-45

-90

-135

180

135

90

45

630 Hz

800 Hz

1000 Hz

1250 Hz

0

-45

-90

-135

180

135

90

45

1600 Hz

2000 Hz

2500 Hz

3150 Hz

0

-45

-90

-135

180

135

90

45

4000 Hz

5000 Hz

6300 Hz

8000 Hz

0

-45

-90

-135

180

135

90

45

10000 Hz

12000 Hz

16000 Hz

HORIZONTAL POLAR DATA (Gridlines: 6 dB axial / 15 degree radial)

See NOTES GRAPHIC DATA for details

Eastern Acoustic Works One Main Street Whitinsville, MA 01588 tel [phone] fax [phone] www.eaw.com

EAW products are continually improved. All specifications are therefore subject to change without notice. Part Number: RD0302 (A) NT29 SPEC December 2005

NT29 Specifications group · J

VERTICAL POLAR DATA (Gridlines: 6 dB axial / 15 degree radial)

See NOTES GRAPHIC DATA for details

0

-45

-90

-135

180

135

90

45

100 Hz

125 Hz

160 Hz

200 Hz

0

-45

-90

-135

180

135

90

45

250 Hz

315 Hz

400 Hz

500 Hz

0

-45

-90

-135

180

135

90

45

630 Hz

800 Hz

1000 Hz

1250 Hz

0

-45

-90

-135

180

135

90

45

4000 Hz

5000 Hz

6300 Hz

8000 Hz

0

-45

-90

-135

180

135

90

45

10000 Hz

12000 Hz

16000 Hz

0

-45

-90

-135

180

135

90

45

1600 Hz

2000 Hz

2500 Hz

3150 Hz

Eastern Acoustic Works One Main Street Whitinsville, MA 01588 tel [phone] fax [phone] www.eaw.com

EAW products are continually improved. All specifications are therefore subject to change without notice. Part Number: RD0302 (A) NT29 SPEC December 2005

NT29 Specifications group · J

INPUT PANEL

NOTES

TABULAR DATA

1. Measurement/Data Processing Systems: Primary - FChart: proprietary EAW software; Secondary - Brüel & Kjær 2012.

2. Microphone Systems: Earthworks M30; Brüel & Kjær 4133

3. Measurements: Dual channel FFT; length: 32 768 samples; sample rate: 48 kHz; logarithmic sine wave sweep.

4. Measurement System Qualification (includes all uncertainties): SPL: accuracy +/-0.2 dB @ 1 kHz, precision +/-0.5 dB 20 Hz to 20 kHz, resolution 0.05 dB; Frequency: accuracy +/-1 %,

precision +/-0.1 Hz, resolution the larger of 1.5 Hz or 1/48 octave; Time: accuracy +/-10.4 µs, precision +/-0.5 µs, resolution 10.4 µs; Angular: accuracy +/-1°, precision +/-0.5°, resolution 0.5°.

5. Environment: Measurements time-windowed and processed to eliminate room effects, approximating an anechoic environment. Data processed as anechoic or fractional space, as noted.

6. Measurement Distance: 7.46 m. Acoustic responses represent complex summation of the subsystems at 20 m. SPL is referenced to other distances using the Inverse Square Law.

7. Enclosure Orientation: For beamwidth and polar specifications, as shown in Mechanical Specification drawing.

8. Volts/Amperes: Measured rms value of the signal or as noted.

9. Watts: Per audio industry practice, “loudspeaker watts” are calculated as voltage squared divided by rated nominal impedance. Thus, these are not True Watt units of energy as defined by

International Standard.

10. SPL: (Sound Pressure Level) Equivalent to the average level of a signal referenced to 0 dB SPL = 20 microPascals.

11. Subsystem: This lists the transducer(s) and their acoustic loading for each passband. Sub = Subwoofer, LF = Low Frequency, MF = Mid Freque ncy, HF = High Frequency.

12. Operating Mode: Between system elements, a comma (,) = separate amplifier channels; a slash (/) = single amplifier channel. DSP = Digital Signal Processor.
13 . Operating Range: Range where the processed Frequency Response stays within -10 dB SPL of the power averaged SPL within this range; measured on the geometric axis. Narrow band

dips are excepted.

14. Nominal Beamwidth: Design angle for the -6 dB SPL points, referenced to 0 dB SPL as the highest level.

15. Measured Axial Output Limit: SPL for Pink Noise and an average of musical selections at the Limit and Clip thresholds; measured on the geometric axis, referenced to 1 m.

16. Electrical Performance: Input, DSP (Digital Signal Processing), amplifier, and ac mains characteristics.

17. Controls: Functions that can be adjusted by the operator.

18. Indicators: Operating status indicators.

GRAPHIC DATA

1. Resolution: To remove insignificant fine details, 1/12 octave cepstral smoothing was applied to acoustic frequency responses and 1/3 octave cepstral smoothing was applied to the

beamwidth and directivity data. Other graphs are plotted using raw data.

2. Frequency Response: Variation in acoustic output level with frequency for a constant input signal. normalized to 0 dB SPL.

3. Phase Linearity: The difference in phase between the input signal and acoustic output, with signal processing latency removed.

4. Beamwidth: Average angle for each 1/3 octave frequency band where, starting from the rear of the loudspeaker, the output first reaches -6 dB SPL referenced to 0 dB SPLas the highest

level. This method means the output may drop below -6 dB SPL within the beamwidth angle.

6. Directivity: Directivity Index (DI) and Directivity Factor (Q).

5. Polar Data: Horizontal and vertical polar responses for each 1/3 octave frequency band 100 Hz to 16 kHz or Operating Range.

SIGNAL DIAGRAM

LEGEND

DSP/EQ: Integral Digital Signal Processing.
HPF: High Pass Filter for crossover.
LPF: Low Pass Filter for crossover.
LIMIT: Driver and Electronic Protection.
LF/MF/HF: Low Frequency / Mid Frequency / High Frequency.
AMP: Power Amplifier.

2-Way, Bi-Amp

THRU

IN

DSP PC BOARD

INPUT

A / D

INPUT

A/D

HPF

EQ

LIMIT

DELAY

LPF

EQ

LIMIT

DELAY

D/A

D/A

AMPLIFIER &

POWER SUPPLY

ASS’Y

AMP

500 W @ 4 ohm

AMP

1000 W @ 4 ohm

HF

LF

Eastern Acoustic Works One Main Street Whitinsville, MA 01588 tel [phone] fax [phone] www.eaw.com

EAW products are continually improved. All specifications are therefore subject to change without notice. Part Number: RD0302 (A) NT29 SPEC December 2005

NT29 Specifications group · J

NT TECHNOLOGY

NT Design Challenges: The goal for NT loudspeakers was to provide the pristine, transient performance, smooth frequency response, and lack of coloration

of direct radiating studio monitors while providing the powerful, high output needed for professional PAapplications. This meant horn-loading was required for
output capability. However, inherent to horns are two, un-studio-like, but well-known problems: transient smearing or “splashiness” and honk. These
problems are caused by internal reflections within the horn and phase plug. Figure 1 shows the
spectrogram of an ideal, point-source loudspeaker. Figures 2 and 3 show the spectrograms of an NT
loudspeaker optimized with conventional digital signal processing (DSP).

In Figure 2 the spectrogram is set to show some vertical lines in the highest two octaves. These are internal
reflections being emitted from the phase plug after the initial signal. These cause splashy-sounding
transients, significantly reducing "crispness" and high frequency detail. This also causes transient
information to be masked by the reflections from previous signals. Correcting this by phase plug redesign
would significantly degrade efficiency, bandwidth, and frequency response flatness.

In Figure 3 the spectrogram is set to show broader, vertical spikes of sound reflecting from the mouth back
into, then back out of the horn. The period of these repeated spikes corresponds to the frequency of the
prominent, green, horizontal lobe. This lobe shows in-phase summation of the original signal and these
subsequent reflections. All this causes the familiar "honk" in horns, the amount varying with a horn's specific
geometry and beamwidths. Both transient splashiness and honk problems are sometimes assumed to be
non-minimum phase phenomena and uncorrectable. NT proves these assumptions are incorrect.

Gunness Focusing™ : Using innovative analysis tools and methods developed by EAW, the specific
parameters of these problems were isolated and analyzed as to the solutions using DSP. However, the
desired complex filter responses required accuracies grossly lacking in conventional DSP filters based on
the Bilinear Z Transform (BZT). These filters sacrifice response accuracies in the upper audible octaves to
avoid mathematical difficulties involving the Nyquist frequency. This results in filter response magnitude
errors of over 15 dB, with equally flawed phase performance. Using FIR (Finite Impulse Response) filters
would have resulted in latencies in excess of acceptability for real time use. Gunness Focusing avoids
these issues while employing the exact, complex, filter responses required.

The results of applying Gunness Focusing to an NT loudspeaker are shown in Figure 4. Both time smear
and "honk" are largely gone, making NT's spectrogram look quite similar to the ideal in Figure 1. NT's
exceptional frequency and phase responses can be seen in the Performance Data. The change in phase
below about 300 Hz simply reflects the overall high pass characteristic of the loudspeaker.

Amplification: NT's amplifiers are designed specifically for real audio signals by using advanced, intelligent,
power supply control to provide superior audio quality, extraordinary efficiency, cool operation, and invariance
to ac mains disturbances. Circuit protection includes separate power supply and amplifier thermal protection,
HF and overall amplifier overload, and a two-state, over-current limiter. The protection circuits are self­resetting, minimizing audio down-time.

Weight: As with any portable loudspeaker, particularly with integral electronics, the engineering challenge
was eliminating all possible sources of excess weight without compromising EAW's heritage of
exceptionally strong and acoustically inert enclosures. To this end, EAW engineered NT like a finely tuned
racecar, where a high efficiency engine, aluminum flywheel, unique chassis design, drilled foot pedals, and
the like reduce weight, while maintaining strength, and improving performance. Among NT's weight-saving
design elements are: unique joinery to eliminate interior cleats; fly-cutting excess wood, where the full
thickness is not needed; removal of unneeded grille railing; structural aluminum fly tracks that also serve as
handles; and unique, neodymium, Orbital Magnet Arrays™ to reduce driver magnet weight. The electronic
design is so efficient, the entire electronics package (including DSP, heat sinks, connectors, etc.) for the full­range 1500 W power plant, as well as for the 2000 W subwoofer power plant, weighs only 9 lb / 4.1 kg!

The result of this attention to detail is that NT loudspeakers approach the weight of popular, plastic
enclosure, self-powered loudspeakers. However, NT loudspeakers provide the robust, physical and
acoustical performance of Baltic birch plywood enclosures and a lot more amplifier power.

Dependability: NT loudspeakers are bi-amplified, with separate digital processing and amplification for the
LF and HF drivers. The processing incorporates sophisticated digital limiting specifically tailored to driver
limitations on typical, real audio signals. The limiting is also specifically tailored to minimize reduction in sound
quality when operating. This permits very high SPLs with little risk of damaging the drivers.

NT's integral power amplifiers use proven, high efficiency, technology. The DSP settings for all models are
stored in the amplifier assemblies, with dip switches to re-configure them for any model. While the likelihood
of failure is small, a complete amplifier assembly for any NT full-range model or for the NTS22 subwoofer
can be easily replaced in minutes.

NT enclosures have the same birch plywood construction as used in legendary EAW touring products. No
weight-saving modifications impact the ruggedness of this construction. This same mechanical toughness extends to the amplifier design. This means NT
loudspeakers are well-equipped to handle the physical rigors of hard, professional use.

Summary: EAW's engineering efforts resulted in the NT Series: robust, compact, lightweight, loudspeakers that provide the pristine, transient performance,
smooth frequency response, and lack of coloration of direct radiating, studio monitors. Unlike studio monitors, NT has the exceptional power, output, and
directional capabilities as well as the mechanical durability required for professional PA applications.

SPECTROGRAMS: EAW's proprietary spectrograms show the spectrum or frequency content of sound (vertical axis) and its variation in time (horizontal axis), the colors representing intensity.
The width of the data reflects the size of the sliding time window applied to the data, which increases in size with lower frequency. The “data” in the upper right is simply a limitation of the
spectrograph's mathematics and has no relevance.

Figures 1 to 4 (top to bottom)