Dear Fosi Audio Team,
As a prospective S3 Streamer customer, I'm extremely excited about the announced specs (DAC, XLR, Roon Ready, TIDAL Connect). I believe the S3 has the potential to be the best value streamer on the market.
I would like to formally request the inclusion of a critical Digital Signal Processing (DSP) feature that has become a major competitive differentiator:
Digital Bass Management with Crossover functionality.
This feature is successfully implemented in competitors like the
WiiM Ultra and is vital for any proper 2.1 Hi-Fi system setup:
- Dedicated Subwoofer Output (Sub Out): The S3 already features an RCA Sub-Out, but its output needs to be digitally controlled.
- Active Crossover (DSP): The implementation should allow the user to set a single Crossover Frequency(e.g., 80 Hz) so the S3's DSP simultaneously applies:
- Low Pass Filter (LPF): Applied to the Sub Out (sending only bass frequencies, e.g., below 80 Hz, to the subwoofer).
- High Pass Filter (HPF): Applied to the main RCA/XLR outputs (cutting bass frequencies, e.g., below 80 Hz, from the main speakers).
Splitting the signal digitally in this manner is essential. It relieves the main speakers and amplifier of handling the deep bass, resulting in much
cleaner mids and highs, and achieving a significantly better acoustic integration between the main speakers and the subwoofer.
If the S3 can offer this robust Crossover feature (in addition to the expected Parametric EQ), it will become the most complete and competitive 2.1 streaming solution available.
Thank you for your consideration.
Supplementary Note on Digital DSP Advantage
To the Fosi Team:
"To emphasize the value of this feature, it is critical that this crossover be implemented in the
digital domain (DSP), not analog circuits.
The
digital approach (like the WiiM Ultra's) offers three huge benefits over traditional analog crossovers:
- Perfect Accuracy: Digital filters are mathematically exact, ensuring the main speakers' HPF and the subwoofer's LPF match perfectly, which is impossible with variable analog components.
- Flexibility: It allows the team to offer advanced features like adjustable phase, latency/delay alignment, and better integration with future Parametric EQ and Room Correction features.
- Signal Integrity: Applying the crossover in the digital domain, before the AKM DAC, maintains the cleanest possible signal path, preventing the introduction of noise, phase distortion, and signal degradation commonly associated with analog filtering.
Implementing this DSP-based Bass Management will transform the S3 from a good streamer into an
essential 2.1 Hi-Fi component, offering performance and control usually found only in much more expensive pre-amplifiers.