Having had an opportunity to test Onkyo TX-SR383 vs Pioneer SC-LX501, I’d like to share my impression here to facilitate your choice of a new AV receiver.
AV receivers under review have the same number of channels. In terms of power, there are differences, the TX-SR383 has such a ratio W/Ohm - 100/8, 135/6, while the SC-LX501 has a power of 120/8, 180/6. The value of total harmonic distortion is also different, and for the TX-SR383 it is 0.09%, but for the SC-LX501 it is 0.08%.
The manufacturer installed different DACs, the TX-SR383 received the model 192 KHz/24-bit, but the SC-LX501 is equipped with AK4458 384 KHz/32-bit. The Bi-amping function is implemented only in the Pioneer SC-LX501. The model SC-LX501 can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Each of the receivers has a Bluetooth connector. The SC-LX501 has access to the Spotify service.
Support for the HDR function can only boast of each of the AV receivers. The quality of 4K/60Hz signal remains unchanged when transmitting from a source to a TV or projector via HDMI for both receivers. Signaling over HDMI in standby mode can provide the TX-SR383 and the SC-LX501. Video scaling is only possible with the SC-LX501. Operation with the Dolby Vision is only possible with the SC-LX501.
The number of HDMI inputs/outputs varies depending on the receiver, the TX-SR383 has 4/1, and the SC-LX501 has 7/2. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is not supported by the TX-SR383 and the SC-LX501. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. TX-SR383 and SC-LX501 support the standard HDCP 2.2. In the presence of a built-in phono stage for connecting a vinyl player only at Pioneer SC-LX501.
Ability to create 2 Multi zones inherent in both AV receivers. Voice control of the basic functions of the receiver is not realized in both models. There is an ECO mode in neither AV receiver. The Pioneer SC-LX501 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available only in the SC-LX501. Only in the SC-LX501 realized a DTS:X surround technology.