Will the TX-NR6100 damage the 603 S3?

No. The TX-NR6100 is rated for the 603 S3's 8 Ω load as it comes.

What impedance setting should I use for the 603 S3 on the TX-NR6100?

None: the 603 S3 is 8 Ω, and the TX-NR6100 needs no change for it.

Is the TX-NR6100 powerful enough for the 603 S3?

More than you need. From a seat 2 m away, loud 95 dB movie peaks take about 13 W per speaker, and the TX-NR6100 is rated 100 W per channel. Cinema reference level, 105 dB peaks, takes about 127 W.

Does the Bowers & Wilkins 603 S3 work with the Onkyo TX-NR6100?

Verdict

Yes

The 603 S3 is 8 Ω, and the TX-NR6100 is rated for speakers down to 4 Ω, so it drives them as is.

Speaker load

8 Ω speaker, rated down to 4 Ω

Power

100 W

More than you need. About 13 W gives 95 dB peaks at 2 m

How to connect them

Connect the 603 S3 speakers to the TX-NR6100's front terminals with speaker wire.
Run AccuEQ with its microphone at your seat.

Plan the 603 S3 and TX-NR6100 in your own room.

Draw your room in 3D, place both, and see every connection checked and how loud they play at your seat. Designing is free.

Build it in your room

The specs that decide it

Bowers & Wilkins 603 S3

Impedance: 8 Ω
Sensitivity: 90 dB (2.83 V, 1 m)
Recommended amplifier power: 30–200 W
MSRP: $2,700 a pair (MSRP, September 2026)

All 603 S3 specs and pairings

Onkyo TX-NR6100

Amplifier channels: 7
Height formats: Dolby Atmos, DTS:X
Lowest speaker impedance: 4 Ω
MSRP: $799 each (MSRP, May 2025)

All TX-NR6100 specs and pairings

Questions about the 603 S3 and TX-NR6100

Does the 603 S3 work with the TX-NR6100?: Yes. The 603 S3 is 8 Ω, and the TX-NR6100 is rated for speakers down to 4 Ω, so it drives them as is.
Will the TX-NR6100 damage the 603 S3?: No. The TX-NR6100 is rated for the 603 S3's 8 Ω load as it comes.
What impedance setting should I use for the 603 S3 on the TX-NR6100?: None: the 603 S3 is 8 Ω, and the TX-NR6100 needs no change for it.
Is the TX-NR6100 powerful enough for the 603 S3?: More than you need. From a seat 2 m away, loud 95 dB movie peaks take about 13 W per speaker, and the TX-NR6100 is rated 100 W per channel. Cinema reference level, 105 dB peaks, takes about 127 W.

Swap one of them

References

Specs verified against the manufacturer's published data. Last checked September 15, 2026.

Brand names are trademarks of their owners. Not affiliated with or endorsed by any manufacturer. 3D models are our approximations. Prices are manufacturer list prices (MSRP) as of the month shown. How we earn from buy links: affiliate disclosure.