Cello Rhapsody Owners manual

Thank you for choosing the Cello Rhapsody amplifier. Your Rhapsody has been individually made, from the

finest parts and materials available. The Rhapsody utilizes proprietary circuitry and processes, developed by
Matthew James, L.L.C., that represent true state of the art in audio electronics. The Rhapsody is designed to
perform to specification for decades of enjoyment. We hope the Rhapsody provides you with complete
satisfaction. Please read this information carefully, and care for your Rhapsody so that it will retain its value,
appearance, and performance.

If you have any questions, contact your authorized Cello representative, or contact Matthew James directly, via

phone [phone]), fax [phone]), or email ([e-mail]). It is our wish to assist you in
any way possible to facilitate your enjoyment. These are the private, home office numbers and email address of
Matthew James’ Managing Partner. As a result, while you can rest assured that your concerns will be treated
with the utmost urgency, the Managing Partner occasionally travels, sleeps, and listens to music, so he may not
always be immediately available to respond.

Product Concept and Description

The Cello Rhapsody amplifier contains the most recent thinking in high-powered amplifier circuitry and
mechanical design from the staff of Matthew James, L.L.C. The primary design criteria for the Rhapsody is to
deliver sound as neutral as possible, while remaining stable under all conditions likely to be encountered in the
reproduction of music and film sound in the home. Available as either a two- or three -channel amplifier, the
Rhapsody is designed to deliver in excess of 200 watts per channel into an 8-ohm load, and more than 400 watts
per channel into a 4-ohm load. When bridged (i.e., two channels, instead of driving two speakers, drive a single
speaker, with one channel handling the (+) positive side of the waveform, and the other channel handling the (-)
negative side of the waveform), the Rhapsody will develop (4) four times the power that it does under normal
operation 800 w/ch into 8 ohms, 1,600 w/ch into 4 ohms.

The Rhapsody is designed to have the lowest possible levels of distortion while under actual use, as opposed to
measuring well simply on a test bench. The circuitry is designed to perform well under the complex resistive,
reactive and regenerative loading which loudspeakers present to an amplifier. And again, it does so without
adding additional forms of distortion before the overload threshold is reached. The desig n approach has been to
place importance on the requirements of actual music and film sound reproduction. Many amplifiers utilize
some form of soft-clip circuitry to deal with overload. The problem is that many of these approaches introduce
additional forms of distortion before the actual overload threshold is reached. Furthermore, most designs to
control overload are not comprehensive in dealing with all of the situations that negatively affect an amplifier’s
ability to remain stable under demanding situations. They might only control voltage overload, while current
and frequency overloads also have a significant impact upon the reproduced sound. The Rhapsody has been
designed to control all three forms of overload under all conditions.

Considerable effort has been made to reduce low frequency errors, because most of the energy in music and film
sound reproduction is present in this part of the frequency spectrum. It is crucial to maintain low
intermodulation distortion of low level, high frequency information in the presence of large low - and mid­frequency signals under complex loading. In the Rhapsody, the driver and output stages are set to have the
lowest distortion at small signal levels and to gradually increase with signal level. While this results in slightly
higher total harmonic distortion (THD) measurements at full power levels, it conversely allows for the lowest
possible distortion under actual listening conditions. Again, the requirements for accurate music and film sound
reproduction have taken precedence in all design decisions.

All electrical connections for signal flow within the Rhapsody are accomplished via flat silver cables insulated
with Kapton, or by heavy, solid copper buss bars. The chassis is manufactured with heavy aluminum plates on

all six sides. (3) Three specially designed feet, utilizing ball bearings of a similarly hardened steel and a
proprietary coating, eliminate the possibility of surface-borne disruptions from affecting the performance of the
circuitry.

The input stage of the Rhapsody amplifier remains under control under any overload condition. The design
tactics were chosen because they provide wide dynamic range and provide a greater measure of resistance to
overload, before loss of control, than other possible choices.

The output stage of the Rhapsody employs six pairs of 250 watt, metal case, bipolar output devices per channel.
The number and type of devices were chosen because they remain stable with a less complex circuit, requiring
less negative feedback, and are easier to match to each other than other possible choices for this stage. The
choice of devices, the location of devices on the heat sinks, and the heat sinks themselves were carefully
considered to minimize the temperature variations among the output devices. The power devices are mounted
with all metal hardware, compression washers and special graphite and metal composite gaskets to insure
maximum thermal conductivity and full utilization of the output devices. Once again, consistent performance,
stability and reliability under normal conditions of actual use were the driving factors in the design.

The location of the transformer was carefully considered relative to the other circuitry in the amplifier that can
be affected by the magnetic fields that it ge nerates. Heavy nickel plated copper buss bars have been utilized to
improve grounding and power distribution within the amplifier. The signal from the amplifier’s audio channels
is delivered to the speaker buss bars via flat silver cables (AWG 10) insulate d with Kapton. Special high
temperature filter capacitors, with high current terminals are used to insure the utmost in performance.

Unpacking

The packing box for the Rhapsody amplifier should arrive in good condition. Please inspect for damage to the
carton, although this is unlikely due to the strength of the carton construction. Open the packing carefully and
save all foam pieces and boxes for re-use in the event the Rhapsody needs to be shipped in the future. Should the
box become lost, please contact your dealer for replacement carton and packing material.

Each carton should contain (1) one Cello Rhapsody amplifier, (1) one AC line cord, (1) one owner’s information
and warranty registration sheet.

Installation

Be certain that the Rhapsody amplifier is installed so that it has proper ventilation. The ambient temperature
should not exceed 122 degrees F (50 degrees C).

Connect inputs 1 & 2 (2-channel version) or 1, 2 & 3 (3-channel version) of the Rhapsody via XLR terminated
interconnect cables, and to the line outputs of your preamplifier or other source component.

Connect outputs 1 & 2 (2-channel version) or 1, 2 & 3 (3-channel version) of the Rhapsody via speaker cables
and to the corresponding terminals of your speakers. Provisions are made for connections up to tri-amp level.

Connect the AC line cord from the IEC connector on the rear of the amplifier to the power outlet in your home.