Will the TX-NR7100 damage the Reserve R400?

No. The TX-NR7100 is rated for the Reserve R400's 8 Ω load as it comes.

What impedance setting should I use for the Reserve R400 on the TX-NR7100?

None: the Reserve R400 is 8 Ω, and the TX-NR7100 needs no change for it.

Is the TX-NR7100 powerful enough for the Reserve R400?

More than you need. From a seat 2 m away, loud 95 dB movie peaks take about 16 W per speaker, and the TX-NR7100 is rated 100 W per channel. Cinema reference level, 105 dB peaks, takes about 160 W.

Does the Polk Reserve R400 work with the Onkyo TX-NR7100?

Verdict

Yes

The Reserve R400 is 8 Ω, and the TX-NR7100 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 16 W gives 95 dB peaks at 2 m

How to connect them

Connect the Reserve R400 speakers to the TX-NR7100's front terminals with speaker wire.
Run Dirac Live with its microphone at your seat.

Plan the Reserve R400 and TX-NR7100 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

Polk Reserve R400

Impedance: 8 Ω
Sensitivity: 89 dB (2.83 V, 1 m)
Recommended amplifier power: 40–200 W
MSRP: $699 each (MSRP, September 2026)

All Reserve R400 specs and pairings

Onkyo TX-NR7100

Amplifier channels: 9
Height formats: Dolby Atmos, DTS:X
Lowest speaker impedance: 4 Ω
MSRP: $1,300 each (MSRP, August 2024)

All TX-NR7100 specs and pairings

Questions about the Reserve R400 and TX-NR7100

Does the Reserve R400 work with the TX-NR7100?: Yes. The Reserve R400 is 8 Ω, and the TX-NR7100 is rated for speakers down to 4 Ω, so it drives them as is.
Will the TX-NR7100 damage the Reserve R400?: No. The TX-NR7100 is rated for the Reserve R400's 8 Ω load as it comes.
What impedance setting should I use for the Reserve R400 on the TX-NR7100?: None: the Reserve R400 is 8 Ω, and the TX-NR7100 needs no change for it.
Is the TX-NR7100 powerful enough for the Reserve R400?: More than you need. From a seat 2 m away, loud 95 dB movie peaks take about 16 W per speaker, and the TX-NR7100 is rated 100 W per channel. Cinema reference level, 105 dB peaks, takes about 160 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.