We've seen quite a few discussions lately about external 10 MHz master clocks:
👉 Is sine wave better than square wave?
👉 Should I choose 50 Ω or 75 Ω?
Here's a short, down-to-earth explanation based on engineering practice and real Hi-Fi system behavior.
TL;DR
- There is no absolute "better" waveform
- In Hi-Fi systems, system matching matters more than waveform theory
- We strongly recommend trying both in your own system and choosing by ear
Why does sine vs square even matter?
From an engineering perspective:
- An OCXO internally oscillates in a near-sine-wave mode
- This is essential for achieving low phase noise
However…
👉 Hi-Fi devices are digital systems
DACs, DDCs, and network streamers typically lock the 10 MHz reference via:
- PLLs
- FPGA logic
- Digital clock receivers
These circuits care more about:
- Edge stability
- Timing precision
—not whether the waveform looks “round” or “smooth”.
Then why do some people hear differences?
That's actually expected.
Different systems may have:
- Different clock input buffers
- Different comparator thresholds
- Different cable and impedance matching
- Different jitter sensitivity
👉 As a result, sine and square wave outputs can sound slightly different in some systems
This doesn't mean one is universally superior — it means one may simply work better in your setup.
What about 50 Ω vs 75 Ω?
A simple rule:
Follow the input specification of your device
- Not specified? → 50 Ω is usually the safe and common choice
- Clearly specified as 75 Ω? → Use 75 Ω
At 10 MHz:
- Short cables are generally forgiving
- But best practice is still matching source, cable, and load impedance
About our clock products (quick note)
Our OCK-2S and OCK-2P clocks:
✅ Support sine or square wave output
✅ Support customized 50 Ω or 75 Ω output impedance
Please note:
- Waveform type (sine / square) is fixed by design
- Output impedance can be customized upon request
- Customized units are non-returnable — please confirm before ordering
