Found in most home theatre receivers/processors, Digital Signal Processing attempt to recreate particular surroundings such as a jazz club, stadium, or church, to name a few. Some manufacturers load up their equipment with a bunch of these sound fields. Rotel, however, prefers to keep them to a minimum, for those who wish to experiment. We believe music should be reproduced faithfully to the original performance. When a musician records an album, it is usually done in good ol' fashioned two-channel stereo, not in an electronically reproduced sound mode. Moreover, it is not realistic to think someone can transform their living room into the same acoustical characteristics as an intimate jazz club or a large outdoor stadium. Multi-channel DVD concert discs, DTS music discs, and DVD-Audio will provide a much more realistic atmosphere over even the most sophisticated DSP modes.

SACD is a high-resolution audio disc format that was developed by Sony and Philips Electronics. SACD is designed to provide high-resolution audio in both stereo and surround sound modes up to 5.1 channels. Not all discs will contain both stereo and surround tracks as this is dependent on the disc itself.

The SACD format uses a process known as Direct Stream Digital (DSD) to encode audio. DSD has a sampling rate of 2822.4kHz and the resolution is 1 bit. SACD recordings can have a wider frequency and dynamic range than conventional CDs.

SACD discs can be one of three types:

• Hybrid - This type of SACD contains an SACD layer compatible with SACD players, as well as a CD layer which is compatible with most standard Red Book CD players.
• Single-layer - This type of SACD contains only one SACD layer compatible with SACD players, and does not contain a CD layer. This type of SACD will not play in a standard CD player.
• Dual-layer - This type of SACD contains two SACD layers for additional data, and no CD layer. This type of SACD will also not play in a standard CD player.

The most typical connection to an audio system for an SACD player is via 6-channel analog connections, thus allowing the SACD player to decode the high resolution audio in the player and stream it to the audio system in an analog format. All current Rotel surround receivers and processors provide an analog multichannel input that would allow connection of an SACD player.

Due to the large bandwidth required to transmit HD audio, the only digital cable with sufficient bandwidth to allow digital streaming of SACD audio is HDMI. However, most HDMI devices will not decode SACD as decoding a DSD signal requires a dedicated circuit solely for the purpose of SACD audio decoding. However, several players that do allow digital streaming of SACD discs will provide an option to convert the digital audio into a more standard PCM digital format, which is a standard digital audio signal that is compatible with most devices.

Damping factor (DF) refers to the ratio of internal impedance of the amplifier to the speaker system. Simply stated the DF is the ability of the amplifier to allow the speaker cone to return to its mean static state as soon as possible, from the momentum generated from a singular pulse. So, if the amplifiers damping factor was very low, the speaker cone would oscillate about its mean static position before it came to a standstill. This then adds coloration to the sound field, which is undesirable.

On the other hand, if the amplifier's internal impedance is high, the speaker cone would encounter resistance on rebound and then continue to bounce about its static mean position until it finally comes to rest. The amplifier then acts like a trampoline for the speaker cone... perhaps desirable for those who like boomy bass, but less desirable for those who want precision. An amplifier with a high damping factor (greater than 20 DF), is able to absorb the energy generated by the cone rebound, and thereby allows the speaker to return to its mean static position as quickly as the speaker design will allow.

HDCD (High Definition Compatible Digital) is an audio format that, by using a special method of encoding and decoding, allows for more audio information to be stored on a disc than is available on a standard CD, while still remaining compatible with a standard CD player as well. In order to gain the sonic benefits of HDCD either the CD player or the receiver the CD player is connected to must be able to decode HDCD.