Power needed
7.5–120 W
per channel, into 8 ohms
To hit 95 dB peaks at 3 m from a pair of Castle Windsor Duke, you need at least 7.5 W a channel. Anything from about 15 W to 120 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
- -88.0 dB effective sensitivity
- 2 dB allowed for optimistic published sensitivity
- Published sensitivity 90 dB, used as 88.0 dB per watt.
Parasound JCM250 with the Castle Windsor Duke
Workable with care
15 dB of headroom, far more than needed. No harm in it. Well above the 150 W the maker rates the speaker for, so keep an eye on the volume knob.
Rated down to 1 ohms - stable into anything this speaker will throw at it.
Power nearly doubles into 4 ohms (250 W to 450 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 Parasound JCM250 specs
·
Clear this amp
229 integrated amplifiers suit the Castle Windsor Duke
Also show the 1 we do not recommend
1
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 that dips to 4.2.
Power nearly doubles into 4 ohms (80 W to 160 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
2
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 that dips to 4.2.
Power nearly doubles into 4 ohms (80 W to 160 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
3
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 that dips to 4.2.
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.
4
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 that dips to 4.2.
Power rises usefully into 4 ohms (90 W to 150 W).
Balanced against the price of the speakers.
5
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 that dips to 4.2.
Power rises usefully into 4 ohms (100 W to 160 W).
Balanced against the price of the speakers.
6
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 that dips to 4.2.
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.
7
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 that dips to 4.2.
Power rises usefully into 4 ohms (100 W to 160 W).
Balanced against the price of the speakers.
8
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 that dips to 4.2.
Power nearly doubles into 4 ohms (70 W to 140 W) - a stiff supply that copes with hard loads.
Sensible value pick against these 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 that dips to 4.2.
Power rises usefully into 4 ohms (100 W to 150 W).
Balanced against the price of the speakers.
10
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 that dips to 4.2.
Power rises usefully into 4 ohms (100 W to 150 W).
Balanced against the price of the speakers.
11
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 (125 W to 250 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
12
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 that dips to 4.2.
Power nearly doubles into 4 ohms (75 W to 150 W) - a stiff supply that copes with hard loads.
Sensible value pick against these speakers.
13
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 that dips to 4.2.
Power nearly doubles into 4 ohms (80 W to 150 W) - a stiff supply that copes with hard loads.
Sensible value pick against these speakers.
14
Excellent match
14 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 (200 W to 400 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
15
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 that dips to 4.2.
Power rises usefully into 4 ohms (80 W to 130 W).
Sensible value pick against these speakers.
16
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 that dips to 4.2.
Power rises usefully into 4 ohms (125 W to 185 W).
Balanced against the price of the speakers.
17
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 that dips to 4.2.
Power rises usefully into 4 ohms (105 W to 160 W).
Sensible value pick against these speakers.
18
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 that dips to 4.2.
Power rises usefully into 4 ohms (120 W to 185 W).
Sensible value pick against these speakers.
19
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 that dips to 4.2.
Power rises usefully into 4 ohms (75 W to 110 W).
Sensible value pick against these speakers.
20
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 that dips to 4.2.
No 4 ohm power rating on file, so we cannot judge current delivery.
Balanced against the price of the speakers.
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
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 that dips to 4.2.
Power nearly doubles into 4 ohms (125 W to 250 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
2
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 (100 W to 190 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
3
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 that dips to 4.2.
Power rises usefully into 4 ohms (100 W to 150 W).
Balanced against the price of the speakers.
4
Excellent match
14 dB of headroom, far more than needed. No harm in it.
Rated down to 4 ohms, comfortable with an 8 ohm speaker that dips to 4.2.
Power nearly doubles into 4 ohms (210 W to 420 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
5
Excellent match
14 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 (175 W to 345 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
6
Workable with care
15 dB of headroom, far more than needed. No harm in it. Well above the 150 W the maker rates the speaker for, so keep an eye on the volume knob.
Rated down to 1 ohms - stable into anything this speaker will throw at it.
Power nearly doubles into 4 ohms (250 W to 450 W) - a stiff supply that copes with hard loads.
Balanced against the price of the speakers.
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.
No 4 ohm power rating on file, so we cannot judge current delivery.
Balanced against the price of the speakers.
8
Workable with care
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. This speaker swings from 8 ohms nominal down to 4.2, and a valve amplifier follows that curve - expect an audible tonal shift, not damage.
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.
Balanced against the price of the speakers.
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 Castle Windsor Duke specs.
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