A device for adjusting a transmit power spectrum of a first transmit/receive device of a communication network, comprising a means for receiving a measure for an attenuation which a signal experiences on a line from the first transmit/receive means to a first subscriber device of the communication network connected to the first transmit/receive means, from the first subscriber device, and a means for determining the transmit power spectrum of the first transmit/receive means for a communication of the first transmit/receive means with the first subscriber device based on the received attenuation measure.