NAD C 325BEE User Manual

C 325BEE Integrated Amplifier

Features

• 50W x 2 Continuous Power into 8 ohms

• 110W, 160W, 220W, IHF Dynamic power into 8, 4 and 2

ohms, respectively

• PowerDrive™

• Full System Remote control including Stand-by/Off

• Headphones socket

• MP socket for attaching portable devices like MP 3 Players

• Relay Input Switching

• Toroidal Power transformer

• 7 Line inputs, including two tape in/outs

• All discrete circuitry

• Short signal path from input to output

• All sockets Gold plated

• Tone controls defeat switch

• Main-amp input & pre-amp output

• Soft ClippingTM

• IR In & Out

• 12 volt trigger output

Details

The pedigree of performance

The C325BEE is the latest in a long and distinguished lineage of amplifiers from NAD. This pedigree
assures you of an amplifier that is technically outstanding and yet affordably priced.

Historically speaking

The C325BEE traces it’s lineage all the way back to the NAD 3020 which was introduced some 30 years
ago. The 3020 was a revelation at the time, setting a technical standard that astonishingly few amps,
regardless of price, could even match, much less better.

Like all great inventions, the premise of the 3020 seems obvious in retrospect. Make an amplifier
that is optimised for musical signals (not just laboratory test tones) and able to cope with the complex
requirements of real loudspeakers (not just laboratory loading resistors). This led to NAD’s redefinition of
how an amplifier should be designed and exactly how much it needed to cost to exceed the expectations
of music lovers. Terms like “Dynamic Headroom” and “Peak Current Capability” that have attained a
permanent place in the audiophile lexicon were coined to describe these incredible NAD amplifiers.

The sound of magic

What is the “magic” that makes one amplifier sound so much better than another? It all comes down to
the experience of the design team and designing the amplifier for its intended use; no more, no less.

An amplifier with Dynamic Headroom sounds “open”, “effortless” and “smooth”. The machine magically
disappears and the music emerges recreating the atmosphere of the original musical performance.

An amplifier with high Peak Current Capability has the “rhythmic punch” that gets your toe tapping and
your heart pounding. It recreates the soul of the music. If an amplifier cannot produce enough current to
cope with a real loudspeaker the sound becomes “thin” and “flat” lacking the third dimension of live music.

The science of magic

NAD has developed several patented amplifier innovations under the direction of Bjorn Erik Edvardsen (aka BEE).

• PowerDrive technology adds huge reserves of Dynamic Headroom without adding cost by ingeniously
matching the amplifier to the speaker load. This is fully automatic in operation and adjusts the power

supply parameters of the amplifier to best cope with the actual
musical signal and specific speaker loading characteristics.

• Soft Clipping eliminates the harsh sound that occurs when
an amplifier is overdriven. This feature also protects sensitive
loudspeaker tweeters that can be easily damaged by the high
frequency distortion caused by clipping (clipping describes the
distorted shape of a musical sine wave when an amplifier is
driven beyond its power rating).

• BEE Clamp is a new answer to an old problem endemic
to all transistor amplifier designs. When the output transistors
produce heat faster than it can be dissipated, the amplifier
becomes momentarily unstable. This happens when the music
has rich high frequency content and the speaker has low or
difficult impedance. The BEE Clamp employs sophisticated real
time monitoring of the output transistors’ load and drive and
“clamps” the base drive to prevent saturation when necessary,
thus improving amplifier stability and waveform fidelity. The
C325BEE can instantly recover from overload, reducing both
the amount and the duration of distortion, regardless of load
impedance.

NAD has a deeper understanding of the nature of musical
sounds and has devised innovative circuits that overcome
the limitations of semiconductors, capacitors, and the other
electronic components that make up an amplifier. This innovation
has resulted in a product that truly excels in the reproduction of
music.

How we made the best better

The C320BEE and its predecessors has been the benchmark
for budget amplifiers for 30 years now, having won every award
in the Hi-Fi industry several times over. Making the C325BEE
better than the C320BEE was a tall order! By “trickling down”
several innovations from NAD’s new state-of-the-art Masters
Series products has resulted in the C325BEE having even
less distortion, less noise, and a more detailed rendition of the
musical recording.

• New DC Servo eliminates sound colouring capacitors in
the signal path. This improves musical detail and eliminates
harmful loudspeaker ‘offset’.

• Patented distortion cancelling circuit uses both feedback
and feedforward to reduce distortion and improve amplifier
stability.

• Highly optimised circuit layout further lowers internal
impedance, improves grounding, and eliminates subtle
magnetic distortions. Lower noise and distortion, and improved
channel separation are a direct result of this optimisation.

• Surface mount (SMD) technology shortens signal paths and
lowers distortion in NAD’s proprietary Class A gain modules.

• BEE Clamp improv es HF stability when driving difficult
speakers.

• Volume Control has minimum volume cancellation circuit to
increase attenuation by 10dB.

• Tone controls are hand trimmed for perfect response
characteristics.

• A new idling current circuit is more accurate with less unit-to­unit variation.

• More rigid chassis has improved mechanical integrity.

• MP Input for easy connection of iPod™, MP3 and other Media
Players employing 3.5mm headphone sockets.

Value, redefined

NAD has yet further improved the class leading amplifier using
new technology developed for its range topping Masters Series
components. The C325BEE is the new benchmark against
which all other affordable amplifiers will be compared. As with
the previous iterations of this classic NAD amplifier, you will
have to spend several times the C325BEE’s asking price before
you can even approach the technical precision and musical
involvement offered by this unassuming looking little amplifier. All
this sophistication and refinement is available now in the NAD
C325BEE; the new value leader in affordable Hi-Fi!

SPECIFICATIONS

Pre-Amp Section

Line level inputs

Input impedance (R+C)

Input sensitivity, rated power

Frequency response (20Hz - 20kHz)*

Line level outputs

Output impedance

Tape

Power Amp Section

Continuous output power into 8Ω

Rated Distortion (THD 20Hz - 20kHz)

Clipping power

IHF dynamic headroom at 8Ω

IHF dynamic power at 8Ω

IHF dynamic power at 4Ω

IHF dynamic power at 2Ω

Damping factor (ref. 8Ω, 50Hz)

Input impedance

Input Sensitivity (for rated power into 8Ω)

Voltage gain

Frequency response; 20Hz-20kHz

Signal/noise ratio; ref 1W

Signal/noise ratio; ref rated power

Phones

Physical Specifications

Dimensions (W x H x D)

Net Weight

Shipping Weight

20kΩ / 470pF

240mV

±0.1dB

80Ω

Source Z + 1kΩ

50W (17dBW)

0.02%

68W (18dBW)

3.4dB

110W (20.4dBW)

160W (22.0dBW)

210W (23.2dBW)

>160

20kΩ/ 470pF

730mV

29dB

+/-0.2dB

100dB

117dB

220Ω

17 1/8 x 3 15/16 x 11 7/16”

(435 x 100 x 290mm)

17.6 lbs (8.0kg)

19.8 lbs (9.0kg)

NAD Electronics International reserves the right to change specifications or features without notice. NAD is a registered trademark of NAD Electronics International. All rights reserved.
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© 11/05 NAD Electronics International.

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