The In-Ear Monitor ET IEM2 professional products are made with two types of Balanced Armature receivers and with a 2-way passive cross-over . The crossover directs the low-mid frequencies to a dedicated receiver, while directing the high frequencies to a dedicated treblen receiver. The system with two receivers has a excellent and balanced frequency response and is ideal for emerging musicians that use for the first time In Ear Monitors. They allow an isolation of 26 dB. They are compatible with wireless transmission systems and portable media devices.