Sennheiser PC 150, MX300 manual Free line of sight, Volume up? - No, There is a simple rule

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Free line of sight

Infra-red light from the TI 150 / TI 300 transmitter is transmitted in the same way as the light from a light bulb. Do not obstruct the path of the light between the transmitter and the receiver, and stay in the room where the transmission is taking place! Make sure that you wear the stethoset receiver the right way round, with the „Sennheiser“ logo at the front.

There is a simple rule:

If you can see the transmitter from where you are, transmission can take place without any interference.

Volume up? – No!

When people use headphones, they tend to choose a higher volume than with loudspeakers. Listening at high volume levels for long periods can lead to permanent hearing defects. Please protect your hearing, Sennheiser headphones have an excellent sound quality even at low volumes.

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