Seite wird geladen


The musicbook: 55 is our offer for music lovers who value excellent sound, but also enjoy whooping it up at times. Punchy, well-contoured lows, most delicately sculptured highs and an extremely natural and homogeneous vocal reproduction are the strong points of this new power amplifier.

The musicbook: 55 is a class D stereo power amplifier based on a multi-patented circuit design, the UCD amplifier. Owing to a circuit layout that’s been reduced to the essentials, a discrete circuit design and careful fine-tuning the musicbook: 55 achieves a sound quality that makes a lot of big bolides look pretty much outdated. A sound, so rich in detail, natural and particularly dynamic! Just lend your ear and you’ll be surprised at how good class D can sound these days.


Connection & Setup

By means of a selector switch the musicbook: 55 is configurable for three different operating modes. In addition to a pure stereo mode, the musicbook: 55 can also be used either in mono mode as a bi-amping amplifier or balanced as a bridged power amp. With many speakers the "vertical" bi-amping produces a considerable gain in transparency and imaging quality with far less colourations. The high-mid range is relieved from the woofer "burden" and behaves like in an active loudspeaker. As distinct from traditional bi-amping, where a second stereo power amp is linked to the speakers, the configuration options of the musicbook: 55 make additional signal cables dispensable with the added benefit of a much better channel separation. The fact that one power amp handles both low and mid-high signals yields an extra plus in coherency and dynamics, since the bass power amp can draw on more than 80% of the power supply’s total output.

Stereo Mode

Mono Bi-Amping Mode

Mono Bridge Mode

The stereo mode offers sufficient power reserves to drive almost any off-the-shelf loudspeakers in an optimal way. The output power of the musicbook: 55 in this mode is 240 W into 4 ohms per channel.

In mono bi-amping mode each speaker is driven by its own power amp. The musicbook: 55 allows "vertical" bi-amping, where each channel of the musicbook: 55 will drive both the high-mid range and the bass range of one side. In this mode most speakers will produce a more open and detailed sound with enhanced dynamics!

In mono bridge mode the amp is used as a balanced push-pull amplifier. The speaker “hangs“ between two active outputs. In this mode the musicbook: 55 provides a maximum output power of 500 W, enabling a correspondingly high level of dynamics!

Intelligent design.

Technical specifications


Mains voltage: 100–240 V, 50–60 Hz
Dimensions: 280 x 220 x 65 mm (W x D x H)
Weight: 3.7 kg
Power consumption: 0.5 W standby mode, 1.0 W idle mode, 800 W max.

Protection circuits

DC at output: power supply switches off.
Excess temperature: amplifier goes into mute until the temperature has dropped by approx. 10 °C.
Output current limiter: amplifier goes into mute for ca. 0.25 seconds. Switching threshold 16 A peak. In case of continuous overdrive the amplifier will go on and off several times in a row.

Automatic turn-on

Input signal switching threshold: approx. 0.5 mV.
Idle mode: power supply active, amplifier muted. Power consumption 1.0 W.
Standby mode: only stand-by power supply active. Power consumption 0.5 W.
Active mode: power supply and amplifier both active. Power consumption depending on volume level 20-50 W average, 800 W max. peak power.
Switch-on times: approx. 2 seconds from idle to active mode; approx. 8 seconds from standby to active mode.
Switch-off times: after 20 minutes the amplifier will return to idle mode, after another 20 minutes to standby mode.

Power Amplifiers

XLR inputs: analog line level inputs with 20 kOhms input impedance.
RCA inputs: analog line level inputs with 10 kOhms input impedance.
Speaker outputs: safety banana lab sockets (4mm) for connecting loudspeakers with 4–8 ohms.
Power output: 240 W into 4 ohms per channel (<1 min).
Maximum output current: 16 A peak.
Gain: 27.8 dB (24.5-times).
Frequency response: 0 Hz – 45 kHz (-3 dB).
THD & noise: <0,05% typ.

Uncomprising quality.


Australian HiFi (Australia) / May 2016

"[..] a match made in heaven… well, Germany really."

Full review >>

sempre audio (Austria) / February 2016

"High-End HiFi in narrow space, combined with elegance and versatility..."

musicbook: 15 & 55

Full review >> (German)

HiFi + (UK) / October 2015

"Truth is, I’m a little shocked at how good the Lindemann musicbook: [...] sounds."

musicbook: 25 & 55

Full review >>

fairaudio (Germany) / April 2015

"These devices are bursting with enthusiasm and dynamic control."

Full review >> (German)

HiFi einsnull (Germany) / April 2015

"Teamwork in its purest form."

musicbook: 15 & 55

Full review >> (German)

6moons / March 2015

"One of these amps is good. Two of them bridged to mono are even better."

Full review >>




The operation manual for the musicbook:55


The brochure for the musicbook series (general information)