Knoll 21K Getting to know the rear panel, Connecting your amplifier, Input connections

Getting to know the rear panel

A.Audio Inputs

Use the INPUT jacks to connect the outputs of a preamplifier, receiver with pre-out connections, CD player, or other control devices.

B.Input Gain Controls

Use these to adjust the input gain of each channel.

C.Product Serial Number

Write this number in the space provided on page “” for future reference.

D.Remote Trigger Input

Use the REMOTE TRIGGER jack to connect a compatible preamplifier, source device, or other product with a 12VDC output (abut 35mA required).

E.Audio Outputs

This is an unbuffered line level output to other devices such as another 21k amplifier.

F.AC Input

Use the included power cord to connect your amplifier to an AC power source.

G.Speaker Outputs

Use the OUTPUT binding posts to connect the amplifier to your speakers: red for positive, black for negative.

Connecting your amplifier

When making connections between any source components and the amplifier, or when making connections to any speaker, be certain that both the input devices and the amplifier are turned off. Unplug all equipment before making any connections so that there will be no unwanted signal transients that can damage equipment or speakers.

Input connections

Connecting the 21K to your source equipment is straightforward. Using the high-quality audio interconnect cables, match the output channel designations on the rear of your source equipment to the input jacks on the rear panel of your amplifier that have the same channel name. When making connections with RCA type plugs on interconnect cables, make certain to gently, but firmly, insert the plug into the jack. Loose connections can cause intermittent sound and may damage your speakers. Some quality RCA plugs may be very tight, and it is important to secure a proper connection between the interconnection cable and the input jack.

Speaker connections

To ensure that the high quality signals produced by your amplifier are carried to your speakers without loss of clarity or resolution, Knoll advises that you use high-quality speaker wire. Many brands of wire are available — the choice may be influenced by the distance between your speakers and the amplifier, the type of speakers you use, personal preferences, along with other factors.

Regardless of the brand or type of speaker wire chosen, we suggest that you use a wire constructed of fine, multi-strand copper with a gauge of 14 or less (the lower the number, the thicker the cable). Wire with a gauge of 16 may be used for short runs of less than 12 feet. We do not recommend that you use any wires with an AWG equivalent of 18 or higher due to the power loss and degradation in performance that will occur.

To connect the amplifiers to your speakers, a pair of binding posts is provided for each channel output. These posts will accept bare wire, spade lugs, or banana type plugs. If bare wire is used for the connections, strip approximately 1/2 inch to 3/4 inch of insulation from the end of each wire and carefully twist the strands of each conductor together. Be sure not to cut the individual strands or twist them off. All strands must be used for optimal performance.

Correct polarity connections are important to maintain proper speaker phasing. When speaker phasing is correct, all speakers move in and out at the same time preserving the imaging of the program material. Out-of-phase connections mean that some