My latest streamer with a “physical” Peppy Meter based on TDA1541(A) (non-oversampling). As the signals come from the DAC, the VU meters are not affected by the streaming services. It took me hundreds of hours to develop. Supports both Pi 4 and Pi 5 (Pi 5 has no sound improvement BTW). Running DietPi (LMS and Squeezelite).
Dual VU meters
Dual TDA1541(A)
Dual power transformer – one is always-ON and the other is switched
I2S signals are galvanically isolated with NVE IL715. VU meters are driven by the square-law compression op-amp BA6138. Output signals are buffered by an op-amp LM358 (works as a voltage follower). The sound from dual TDA1541(A) is significantly better than a single TDA1541(A) (note that I’m using passive I/V, not necessarily true for other ways of output stages)
Objective observation: TDA1541(A) has a more rounded mid and high, vocal density is higher than TDA1387. On the other hand, TDA1387 has a slightly punchier bass, and with more details and layers. You can easily tell how deep and strong the bass is with different songs. That is said, the bass is well controlled with TDA1387.
Subjective observation: TDA1541(A) sounds more musical than TDA1387. In fact, TDA1541 sounds better than TDA1541A in my ears.
