As more users integrate optical networking into their audio systems, we have received many questions from owners of AS8 PRO, AS6, RPI PRO, and FMC regarding how to choose the correct SFP modules and optical fiber.
This guide is intended to provide a clear and unified recommendation, helping users avoid unnecessary experimentation and achieve the most stable performance.
1. Single-Mode vs Multi-Mode
✅ Official Recommendation: Single-Mode SFP
For Hi-Fi audio applications—especially with products such as AS8 PRO, AS6, RPI PRO, and FMC—we recommend Single-Mode SFP modules.
Reasons:
- Higher transmission stability
Single-mode fiber (9/125 μm) has lower modal dispersion, which helps maintain consistent timing behavior.
- Better suited for audio systems
In practical use with AS-series switches and audio FMC setups, single-mode solutions have shown better consistency and predictability.
- Improved noise isolation
Optical links eliminate electrical noise, and single-mode systems tend to provide a cleaner and more controlled signal environment.
All current switches and audio FMC configurations are tested and evaluated using single-mode SFP modules as the reference setup.
⚠️ About Multi-Mode SFP
- Multi-mode SFP modules (OM2 / OM3 / OM4) are technically compatible
- They are mainly designed for short-distance, high-bandwidth data-center environments
- In Hi-Fi audio systems, they generally provide less consistent results
➡️ For this reason, multi-mode SFP is not our preferred recommendation for AS8 PRO, AS6, RPI PRO, or FMC-based audio systems.
2. Single-Fiber vs Dual-Fiber
✅ Official Recommendation: Dual-Fiber SFP
How it works
- Two fibers are used: one for transmit, one for receive
- Typical wavelength: 1310 nm
- Uses standard LC-LC duplex optical fiber
Why it is recommended for AS-series and audio FMC users:
- Simple and mature architecture
- Plug-and-play operation
- Best overall compatibility
- Proven long-term stability in real-world audio systems
Our internal testing, tuning process, and user feedback for AS8 PRO, AS6, RPI PRO, and FMC are all based on Single-Mode + Dual-Fiber SFP configurations.
⚠️ About Single-Fiber (BiDi) SFP
- Uses one fiber with different wavelengths for TX and RX
- Requires matched A/B module pairs
- More complex and sensitive to module matching
➡️ Single-fiber SFP may be used when cabling is limited, but it is not recommended as the first choice for audio systems.
3. Official Recommended Configuration
SFP Module
- Single-Mode
- Dual-Fiber
- 1G (1000BASE-LX)
- 1310 nm
Optical Fiber Cable
- Single-Mode LC-LC duplex fiber
- Specification: 9/125 μm
- Recommended even for short distances (1–3 meters)
4. About Third-Party SFP Modules
Many AS8 PRO / AS6 / RPI PRO / FMC users ask whether third-party SFP modules can be used.
Different brands vary in:
- Optical power
- Compatibility
- Long-term stability
Untested modules may result in:
- Recognition issues
- Occasional link drops
- Reduced reliability over time
➡️ For best and most consistent results, we recommend using officially supplied SFP modules that have been long-term tested with our audio products.
5. Conclusion
For AS8 PRO, AS6, RPI PRO, and FMC users seeking maximum stability and minimum complexity:
choose Single-Mode · Dual-Fiber SFP modules.
If you are unsure about compatibility or configuration, please contact our support team before purchasing. We are happy to help you select the most suitable SFP and optical fiber solution for your system.
