Power needed
25–400 W
per channel, into 6 ohms
To hit 95 dB peaks at 3 m from a pair of Harbeth M40.5 XD2, you need at least 25 W a channel. Anything from about 50 W to 400 W a channel is comfortable; past that, more watts stop buying you anything.
Show the working
- 95 dB target at the seat
- +4.8 dB for 3.0 m of distance
- -3 dB for a stereo pair
- -82.8 dB effective sensitivity
- 1.2 dB taken off to convert the 6 ohm 2.83V rating to dB per watt
- 2 dB allowed for optimistic published sensitivity
- Published sensitivity 86 dB, used as 82.8 dB per watt.
Marantz PM-10 with the Harbeth M40.5 XD2
Excellent match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (200 W to 400 W) - a stiff supply that copes with hard loads.
Full Marantz PM-10 specs
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Clear this amp
149 integrated amplifiers suit the Harbeth M40.5 XD2
Also show the 29 we do not recommend
1
Excellent match
9 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 (125 W to 250 W) - a stiff supply that copes with hard loads.
Sensible value pick against these speakers.
2
Excellent match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (200 W to 400 W) - a stiff supply that copes with hard loads.
Sensible value pick against these speakers.
3
Excellent match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (200 W to 380 W) - a stiff supply that copes with hard loads.
Sensible value pick against these speakers.
4
Excellent match
9 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 (125 W to 250 W) - a stiff supply that copes with hard loads.
Sensible value pick against these speakers.
5
Good match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power rises usefully into 4 ohms (150 W to 250 W).
Sensible value pick against these speakers.
6
Excellent match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (200 W to 380 W) - a stiff supply that copes with hard loads.
Sensible value pick against these speakers.
7
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power rises usefully into 4 ohms (185 W to 275 W).
Sensible value pick against these speakers.
8
Excellent 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 (200 W to 400 W) - a stiff supply that copes with hard loads.
Well below the speakers - leaves money on the table, but nothing wrong with it.
9
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (150 W to 300 W) - a stiff supply that copes with hard loads.
Well below the speakers - leaves money on the table, but nothing wrong with it.
10
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power rises usefully into 4 ohms (180 W to 300 W).
Sensible value pick against these speakers.
11
Good match
8 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.
No 4 ohm power rating on file, so we cannot judge current delivery.
Sensible value pick against these speakers.
12
Good match
8 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (100 W to 200 W) - a stiff supply that copes with hard loads.
Sensible value pick against these speakers.
13
Good match
12 dB of headroom, far more than needed. No harm in it.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (300 W to 550 W) - a stiff supply that copes with hard loads.
Well below the speakers - leaves money on the table, but nothing wrong with it.
14
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power rises usefully into 4 ohms (210 W to 340 W).
Well below the speakers - leaves money on the table, but nothing wrong with it.
15
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power rises usefully into 4 ohms (180 W to 270 W).
Well below the speakers - leaves money on the table, but nothing wrong with it.
16
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power rises usefully into 4 ohms (200 W to 350 W).
Well below the speakers - leaves money on the table, but nothing wrong with it.
17
Good match
10 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power rises usefully into 4 ohms (190 W to 280 W).
Well below the speakers - leaves money on the table, but nothing wrong with it.
18
Good match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (125 W to 250 W) - a stiff supply that copes with hard loads.
Well below the speakers - leaves money on the table, but nothing wrong with it.
19
Good match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (125 W to 250 W) - a stiff supply that copes with hard loads.
Well below the speakers - leaves money on the table, but nothing wrong with it.
20
Good match
12 dB of headroom, far more than needed. No harm in it.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
Power nearly doubles into 4 ohms (300 W to 580 W) - a stiff supply that copes with hard loads.
Well below the speakers - leaves money on the table, but nothing wrong with it.
Showing the best 20 of 149. Narrow it with the price range below, or a different budget split.
18 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
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
No 4 ohm power rating on file, so we cannot judge current delivery.
No current price on file for this amplifier.
2
Good match
12 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.
No 4 ohm power rating on file, so we cannot judge current delivery.
Sensible value pick against these speakers.
3
Good match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
No 4 ohm power rating on file, so we cannot judge current delivery.
Sensible value pick against these speakers.
4
Good match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
No 4 ohm power rating on file, so we cannot judge current delivery.
Well below the speakers - leaves money on the table, but nothing wrong with it.
5
Good match
11 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
No 4 ohm power rating on file, so we cannot judge current delivery.
Well below the speakers - leaves money on the table, but nothing wrong with it.
6
Good match
9 dB of headroom over what this speaker needs - peaks stay clean.
Rated down to 4 ohms, comfortable with a 6 ohm speaker.
No 4 ohm power rating on file, so we cannot judge current delivery.
Well below the speakers - leaves money on the table, but nothing wrong with it.
7
Good match
10 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.
No 4 ohm power rating on file, so we cannot judge current delivery.
Well below the speakers - leaves money on the table, but nothing wrong with it.
8
Good match
8 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.
No 4 ohm power rating on file, so we cannot judge current delivery.
Sensible value pick against these speakers.
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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 Harbeth M40.5 XD2 specs.