What amplifier does the Castle Knight 5 need?

Pick a speaker and tell us how loud you listen and how big the room is. We work out the power it actually needs, check which amplifiers can safely drive its impedance, and rank 298 amplifiers against it.

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Passive speakers only - a powered speaker already has its amplifier inside.
Changes the order only. Nothing is hidden for costing too little or too much.
Castle Knight 5
Castle Knight 5
Floor-standing
91 dB · 8 ohm
Full specs →
Power needed
6.0–95 W
per channel, into 8 ohms

To hit 95 dB peaks at 3 m from a pair of Castle Knight 5, you need at least 6.0 W a channel. Anything from about 12 W to 95 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
  • -89.0 dB effective sensitivity
  • 2 dB allowed for optimistic published sensitivity
  • Published sensitivity 91 dB, used as 89.0 dB per watt.

WiiM Amp Pro with the Castle Knight 5

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 (60 W to 120 W) - a stiff supply that copes with hard loads.
Full WiiM Amp Pro specs · Clear this amp
 
$90 $25,000

229 integrated amplifiers suit the Castle Knight 5

Also show the 1 we do not recommend
1
OSD Nero Stream XD2
OSD Nero Stream XD2
Integrated Amplifier · Class D · 60 W into 8 ohms · $400
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 (60 W to 120 W) - a stiff supply that copes with hard loads.
2
Eversolo Play
Eversolo Play
Integrated Amplifier · Class D · 60 W into 8 ohms · $699
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 (60 W to 110 W) - a stiff supply that copes with hard loads.
3
WiiM Amp
WiiM Amp
Integrated Amplifier · Class D · 60 W into 8 ohms · $299
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 (60 W to 120 W) - a stiff supply that copes with hard loads.
4
WiiM Amp Pro
WiiM Amp Pro
Integrated Amplifier · Class D · 60 W into 8 ohms · $379
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 (60 W to 120 W) - a stiff supply that copes with hard loads.
5
Denon PMA-1600NE
Denon PMA-1600NE
Integrated Amplifier · Class A/B · 70 W into 8 ohms · $2,099
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 (70 W to 140 W) - a stiff supply that copes with hard loads.
6
Denon PMA-1700NE
Denon PMA-1700NE
Integrated Amplifier · Class A/B · 70 W into 8 ohms · $2,099
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 (70 W to 140 W) - a stiff supply that copes with hard loads.
7
Technics SU-G700M2 Grand Class
Technics SU-G700M2 Grand Class
Integrated Amplifier · Class D · 70 W into 8 ohms · $2,700
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 (70 W to 140 W) - a stiff supply that copes with hard loads.
8
PrimaLuna EVO 400 Integrated
PrimaLuna EVO 400 Integrated
Integrated Amplifier · Class A/B · 70 W into 8 ohms · $6,495
Excellent 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 89.0 dB this speaker is efficient enough that 70 W is comfortable.
9
Audio Research I/70
Audio Research I/70
Integrated Amplifier · Class A/B · 70 W into 8 ohms · $9,950
Excellent 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 89.0 dB this speaker is efficient enough that 70 W is comfortable.
10
Yamaha WXA-70A
Yamaha WXA-70A
Integrated Amplifier · 55 W into 8 ohms · $1,300
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 (55 W to 105 W) - a stiff supply that copes with hard loads.
11
Yamaha WXA-50
Yamaha WXA-50
Integrated Amplifier · Class D · 55 W into 8 ohms · $599
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 (55 W to 105 W) - a stiff supply that copes with hard loads.
12
SVS Prime SoundBase
SVS Prime SoundBase
Integrated Amplifier · Class D · 75 W into 8 ohms · $699
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 (75 W to 150 W) - a stiff supply that copes with hard loads.
13
Cambridge Audio Evo 75
Cambridge Audio Evo 75
Integrated Amplifier · Class D · 75 W into 8 ohms · $2,499
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 (75 W to 150 W) - a stiff supply that copes with hard loads.
14
Marantz Stereo 70s
Marantz Stereo 70s
Stereo Receiver · Class A/B · 75 W into 8 ohms · $1,000
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 (75 W to 150 W) - a stiff supply that copes with hard loads.
15
Onkyo Muse Y-40
Onkyo Muse Y-40
Integrated Amplifier · Class D · 75 W into 8 ohms · $1,000
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 (75 W to 150 W) - a stiff supply that copes with hard loads.
16
Musical Fidelity M2si
Musical Fidelity M2si
Integrated Amplifier · Class A/B · 76 W into 8 ohms · $1,299
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 (76 W to 135 W) - a stiff supply that copes with hard loads.
17
Rotel A14 MKII
Rotel A14 MKII
Integrated Amplifier · Class A/B · 80 W into 8 ohms · $1,600
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 (80 W to 150 W) - a stiff supply that copes with hard loads.
18
Denon PMA-3000NE
Denon PMA-3000NE
Integrated Amplifier · Class A/B · 80 W into 8 ohms · $3,799
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 (80 W to 160 W) - a stiff supply that copes with hard loads.
19
Denon AE PMA-A110
Denon AE PMA-A110
Integrated Amplifier · Class A/B · 80 W into 8 ohms · $3,999
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 (80 W to 160 W) - a stiff supply that copes with hard loads.
20
Rotel S14
Rotel S14
Integrated Amplifier · Class A/B · 80 W into 8 ohms · $2,499
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 (80 W to 150 W) - a stiff supply that copes with hard loads.

Showing the best 20 of 229. 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
PrimaLuna EVO 400 Power
PrimaLuna EVO 400 Power
Power Amplifier · Class A/B · 70 W into 8 ohms · $5,995
Excellent 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 / 16 ohm.
A valve amplifier makes the same power on each tap, so what matters is sensitivity - and at 89.0 dB this speaker is efficient enough that 70 W is comfortable.
2
Rogue Audio Stereo 100
Rogue Audio Stereo 100
Power Amplifier · Class A/B · 100 W into 8 ohms · $4,195
Excellent match
12 dB of headroom, far more than needed. No harm in it.
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 89.0 dB this speaker is efficient enough that 100 W is comfortable.
3
Naim NAP 250
Naim NAP 250
Power Amplifier · Class A/B · 100 W into 8 ohms · $8,999
Excellent 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.
Power nearly doubles into 4 ohms (100 W to 190 W) - a stiff supply that copes with hard loads.
4
PrimaLuna EVO 300 Power
PrimaLuna EVO 300 Power
Power Amplifier · Class A/B · 44 W into 8 ohms · $4,695
Excellent match
9 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 89.0 dB this speaker is efficient enough that 44 W is comfortable.
5
PrimaLuna EVO 200 Power
PrimaLuna EVO 200 Power
Power Amplifier · Class A/B · 44 W into 8 ohms · $3,795
Excellent match
9 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 89.0 dB this speaker is efficient enough that 44 W is comfortable.
6
Cambridge Audio MXW70
Cambridge Audio MXW70
Power Amplifier · Class D · 70 W into 8 ohms · $599
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 (70 W to 125 W).
7
PrimaLuna EVO 100 Power
PrimaLuna EVO 100 Power
Power Amplifier · Class A/B · 40 W into 8 ohms · $3,095
Excellent match
8 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 89.0 dB this speaker is efficient enough that 40 W is comfortable.
8
MOON 330A
MOON 330A
Power Amplifier · Class A/B · 125 W into 8 ohms · $4,400
Excellent match
13 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.
Were these amplifier recommendations useful?
It helps us tune the matching, and we read every comment.

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 Castle Knight 5 specs.

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