Methods, systems, and devices for wireless communication are described. A wireless device may determine that a channel is reciprocal and perform an implicit sounding process. During the implicit sounding process, the wireless device may estimate the uplink channel by measuring a first uplink multi-user multiple input multiple output (MU-MIMO) transmission. The wireless devices may then update the uplink channel estimation based by measuring a second MU-MIMO transmission that is received after a downlink transmission from the wireless device. Based on the updated uplink channel estimation, the wireless device may send a beamformed MU-MIMO transmission to a number of other wireless devices.