High-Pitched Buzzing Or Whirring Operation Noise In The Computer - Yamaha I88X Bedienungsanleitung

About connections with external devices when using the i88X with a computer
When using audio devices, musical instruments and computers at the same time, there is bound to
be some noise in the system, the amount of which depends on the connections. Knowing how to
minimize noise is extremely important when designing and setting up a studio.
As advanced as the i88X is, it too is susceptible to noise. Various types of noise may be generated
and recorded to your audio sequencer, depending on the power sources/grounding scheme and
how the various devices are connected.
There is no ideal way to completely eliminate such noise. However, one can decrease noise by iso-
lating the cause and applying a suitable remedy. Below are a couple of examples that may apply.

• High-pitched buzzing or whirring operation noise in the computer

This is caused by operation noise of the computer leaking to other devices through the mLAN
cable or audio cable, and may be caused by improper grounding of the power source.
• Low humming noise
Noise of this type is generally due to improper grounding of the power source.
The noise may differ depending on the circumstances (specifications of each device and loca-
NOTE
tions of use).
If problems like these happen, try the following measures to minimize the noise.
If the noise disappears when turning down the volume of the i88X and/or if the noise persists
NOTE
even when disconnecting the mLAN cable or turning off the computer, other reasons for the
noise are likely. Refer to the Troubleshooting section in the Owner's Manual.
1. Use balanced cable connections when connecting analog audio.
By using proper balanced connections, you can minimize the noise.
This may have no effect depending on the specifications of the connected device.
NOTE
■ Recommended Cables
i88X Inputs
Outputs of connected devices / i88X inputs (balanced)
Balanced
(mixer, mic preamp, etc.)
Unbalanced
(MIDI tone generator, etc.)
i88X Outputs
i88X outputs (OUTPUT1-OUTPUT8) / Inputs of connected devices (balanced)
Balanced TRS 1/4" phone ↔ TRS phone / XLR balanced cable
Balanced
2. Insert a conventional direct box (passive, with transformer and ground lift switch) for con-
necting the audio (analog) cable.
You may want to use several direct boxes when connecting multiple devices.
NOTE
Example: OUTPUT 1/2 of i88X – [direct box] – powered speaker
Synthesizer – [direct box] – i88X
3. Changing the power source for each device.
WARNING
Attempting this remedy is extremely dangerous and may result in electric shock. It should be done only by
qualified, experienced personnel. Contact your nearest Yamaha representative or an authorized distribu-
tor (see the last page of the Owner's Manual).
TRS 1/4" phone / XLR ↔ TRS phone / XLR balanced cable
TRS 1/4" phone / XLR ↔ TRS phone balanced cable
Unbalanced 1/4" phone ↔ TRS phone / XLR balanced cable
Unbalanced 1/4" phone ↔ TRS phone balanced cable
i88X inputs
Ch. 1-2
Ch. 3-8
Ch. 1-2
Ch. 3-8
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