NAD 2155 Specification Sheet

2155 Power Amplifier

Date of manufacture : Jan 85 - Jan 87

Please note that this document contains the text from the original product brochure, and some technical statements may now be out of date

• Power output conservatively rated at 55 watts per channel into 8 or 4 ohms.

• +3 dB IHF Dynamic Headroom for peaks: 110 W/ch at 8 ohms, 130 W/ch at 4 ohms.

• High-current output stage, able to deliver peak currents up to 40 amperes for precise control of voice

coil motion with speaker impedances as low as 2 ohms.

• Bridging circuit yields 150 watts continuous power, 250 watts IHF dynamic power.

• Exclusive NAD impedance selector optimises power delivery to either high or low speaker impedance.

• Soft Clipping™ minimises distortion at output levels above the rated power.

NAD leads the audio industry in producing amplifiers with high-headroom circuitry and high-current out-

put stages, precisely the qualities needed for musically accurate reproduction of today’s wide-range

analogue and digital recordings. The 2155 power amp is one of the finest in a long tradition of highly

praised NAD amplifiers, with increased power, improved reliability, and numerous refinements in sound

quality. As a high-current high-headroom power amplifier it drives even “difficult” loudspeakers to

surprisingly high volume levels with clean, solid, full-bodied musical sound that remains refreshingly free

from distortion even in transient peaks.

The 2155, which is simply the power amplifier section of the 3155 and 7155 packaged on a separate

chassis, is NAD’s “building-block” amp, offering a variety of convenient and economical approaches to

up-grading a stereo system for higher performance and power. The 2155 is an obvious choice if you

want to upgrade from a low-powered receiver or integrated amp, or if you are using a separate

preamplifier. If you need still higher power, a pair of 2155s in the “bridged” mode deliver nearly three

times as much power output for only twice the cost.

The 2155 delivers substantially more than its conservatively rated 55 watts/channel into the complex and

varying impedances of real loudspeakers. In the bridged monophonic mode this amplifier is rated

conservatively at 150 watts continuous output. And these amplifiers maintain a full 3 dB of IHF dynamic

headroom (2.5 dB in bridged mode), meaning that they deliver twice their rated power in brief bursts:

over 110 watts/channel in stereo and about 250 watts in bridged configuration. This headroom for

peaks is crucially important for reproducing the uncompressed transients in modern digital and DBX-

encoded recordings.

When combined as a bridged stereo pair, these amplifiers function as a 150 W/ch stereo amplifier with

250 watts per channel of short-term output. That power, together with the remarkable flexibility and

flawless sonic performance of the 7155 or 3155’s preamplifier section, make these combinations

remarkable best-buy systems.