Power needed
7.5–100 W
per channel, into 8 ohms
To hit 95 dB peaks at 3 m from a pair of Polk Audio RC85i, you need at least 7.5 W a channel. More than 100 W is wasted here - that is all Polk Audio rates the speaker to take.
Show the working
- 95 dB target at the seat
- +4.8 dB for 3.0 m of distance
- -3 dB for a stereo pair
- -88.0 dB effective sensitivity
- 2 dB allowed for optimistic published sensitivity
- Published sensitivity 90 dB, used as 88.0 dB per watt.
MOON 330A with the Polk Audio RC85i
Good match
12 dB of headroom, far more than needed. No harm in it.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (125 W to 250 W) - a stiff supply that copes with hard loads.
A power amplifier: you will need a preamplifier, or a streamer with a volume control, as well.
Full MOON 330A specs
·
Clear this amp
224 integrated amplifiers suit the Polk Audio RC85i
Also show the 1 we do not recommend
1
Excellent match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 3 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (100 W to 200 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
2
Excellent match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (60 W to 120 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
3
Excellent match
8 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (50 W to 100 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
4
Excellent match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (60 W to 120 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
5
Excellent match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (60 W to 120 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
6
Good match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Barely gains into 4 ohms (90 W to 120 W) - a modest power supply.
Balanced against the price of the speakers.
7
Excellent match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (75 W to 150 W) - a stiff supply that copes with hard loads.
Costs more than the speakers - worth it only if you plan to upgrade them later.
8
Workable with care
13 dB of headroom, far more than needed. No harm in it. Well above the 100 W the maker rates the speaker for, so keep an eye on the volume knob.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
No 4 ohm power rating on file, so we cannot judge current delivery.
Balanced against the price of the speakers.
9
Good match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
No 4 ohm power rating on file, so we cannot judge current delivery.
Sensible value pick against these speakers.
10
Excellent match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (55 W to 105 W) - a stiff supply that copes with hard loads.
Costs more than the speakers - worth it only if you plan to upgrade them later.
11
Good match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power rises usefully into 4 ohms (60 W to 100 W).
Costs more than the speakers - worth it only if you plan to upgrade them later.
12
Good match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Barely gains into 4 ohms (60 W to 70 W) - a modest power supply.
Balanced against the price of the speakers.
13
Good match
8 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Rated at the same 50 W into 4 ohms as into 8 - the power supply runs out before the load does.
Balanced against the price of the speakers.
14
Excellent match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (60 W to 110 W) - a stiff supply that copes with hard loads.
Costs more than the speakers - worth it only if you plan to upgrade them later.
15
Excellent match
12 dB of headroom, far more than needed. No harm in it.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (125 W to 250 W) - a stiff supply that copes with hard loads.
Costs more than the speakers - worth it only if you plan to upgrade them later.
16
Excellent match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (75 W to 150 W) - a stiff supply that copes with hard loads.
Far more expensive than the speakers. Spend it on speakers first.
17
Excellent match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (75 W to 150 W) - a stiff supply that copes with hard loads.
Far more expensive than the speakers. Spend it on speakers first.
18
Excellent match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (100 W to 200 W) - a stiff supply that copes with hard loads.
Far more expensive than the speakers. Spend it on speakers first.
19
Excellent match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (100 W to 200 W) - a stiff supply that copes with hard loads.
Far more expensive than the speakers. Spend it on speakers first.
20
Excellent match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (76 W to 135 W) - a stiff supply that copes with hard loads.
Far more expensive than the speakers. Spend it on speakers first.
Showing the best 20 of 224. Narrow it with the price range below, or a different budget split.
68 power amplifiers that would also drive them
Listed separately because they are not a complete system: a power amplifier has no volume control and no inputs to speak of, so you need a preamplifier or a streaming preamp as well. Worth it if you already own one, or if you want to buy the two halves separately.
1
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power rises usefully into 4 ohms (70 W to 125 W).
Costs more than the speakers - worth it only if you plan to upgrade them later.
2
Workable with care
14 dB of headroom, far more than needed. No harm in it. Well above the 100 W the maker rates the speaker for, so keep an eye on the volume knob.
Rated down to 2 ohms - stable into anything this speaker will throw at it.
No 4 ohm power rating on file, so we cannot judge current delivery.
Sensible value pick against these speakers.
3
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Has a 8 ohm tap, which is exactly what this 8 ohm speaker wants. Taps: 4 / 8 / 16 ohm.
A valve amplifier makes the same power on each tap, so what matters is sensitivity - and at 88.0 dB this speaker is efficient enough that 70 W is comfortable.
Far more expensive than the speakers. Spend it on speakers first.
4
Good match
11 dB of headroom over what this speaker needs - peaks stay clean.
Has a 8 ohm tap, which is exactly what this 8 ohm speaker wants. Taps: 4 / 8 ohm.
A valve amplifier makes the same power on each tap, so what matters is sensitivity - and at 88.0 dB this speaker is efficient enough that 100 W is comfortable.
Far more expensive than the speakers. Spend it on speakers first.
5
Good match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 2 ohms - stable into anything this speaker will throw at it.
Power nearly doubles into 4 ohms (100 W to 190 W) - a stiff supply that copes with hard loads.
Far more expensive than the speakers. Spend it on speakers first.
6
Good match
12 dB of headroom, far more than needed. No harm in it.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power nearly doubles into 4 ohms (125 W to 250 W) - a stiff supply that copes with hard loads.
Far more expensive than the speakers. Spend it on speakers first.
7
Good match
13 dB of headroom, far more than needed. No harm in it.
Rated down to 2 ohms - stable into anything this speaker will throw at it.
Power nearly doubles into 4 ohms (150 W to 300 W) - a stiff supply that copes with hard loads.
Far more expensive than the speakers. Spend it on speakers first.
8
Good match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with an 8 ohm speaker.
Power rises usefully into 4 ohms (100 W to 150 W).
Far more expensive than the speakers. Spend it on speakers first.
Were these amplifier recommendations useful?
It helps us tune the matching, and we read every comment.
Thanks. Anything you would add?
Optional, and it goes straight to the person who maintains this page.
Thanks - noted.
Sensitivity and impedance figures are the manufacturer's own. We read sensitivity as dB at 2.83 V/1 m and take 2 dB off it, because published figures run high. Treat the result as a well-founded starting point, not a measurement. Full Polk Audio RC85i specs.
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