This is a review and detailed measurements of the NAD M23 Class D stereo power amplifier. It is on kind loan from a member and costs US $3,749.
The M23 sports the nice look of other "Masters" series NAD product including substantial weight for a class D amplifier. The only miss is the touch button on top of the unit instead of the NAD logo. The touch sensitivity seems a lot better than previous NAD amplifiers though. Back panel shows the connections you expect:
The M23 is based on the Purifi amplifier which we know to be a high performance amplifier. NAD has differentiated itself by designing its own switchmode power supply. Let's see if that brings something to the party.
NAD M23 Amplifier Measurements
Let's start with our usual 4 ohm dashboard using XLR input:
We get slightly higher gain than reference design but that seems to have cost us a bit in noise, knocking down SINAD a couple of dBs. Strangely, we get that back partially by using RCA input:
Using an average of 102 dB SINAD, the M23 breaks into our top lowest noise+distortion amplifiers ever tested:
Noise performance is still excellent:
Frequency response is flat and load independent which is what we want to see:
Multitone test shows vanishingly low distortion:
New 19+20 kHz test runs at higher amplitude than Multitone so shows higher distortion spikes:
Crosstalk is extremely good:
Let's get into our power measurement and see if the custom power supply is doing us some good:
We definitely have more power than the reference which is a great thing. I also like the conservative and accurate power specifications.
Transfer function gets a bit uneven at higher frequencies but calms way down by 1 KHz:
The power supply seems to be juicing up the 20 Hz response.
So far our tests have been with resistive loads of 4 and 8 ohm. Let's add reactive (capacitive/inductive) load into the equation including going down to 2 ohms:
Wow, this thing is so load independent! I don't think I have tested an amplifier this good so far.
The amplifier is stable on power on:
Pop on is likely inaudible but you might hear something when you power it down (all done with the soft on/off control):
Couldn't figure out why the noise level was higher after I turned it off for the second time. Maybe it takes a while to drain down to nothing. It is not consequential though.
Conclusions
NAD shows how to take a standard design and make it its own with value added on enclosure, and custom power supply. The latter adds good bit more short term power to the amplifier which in my opinion is quite a bit more important than a bit of noise performance that is lost. You pay for this but remember the cost is that of the retail so margins are baked in for retailers.
I am happy to recommend the NAD M23 stereo amplifier. It is a job well done.
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As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The M23 sports the nice look of other "Masters" series NAD product including substantial weight for a class D amplifier. The only miss is the touch button on top of the unit instead of the NAD logo. The touch sensitivity seems a lot better than previous NAD amplifiers though. Back panel shows the connections you expect:
The M23 is based on the Purifi amplifier which we know to be a high performance amplifier. NAD has differentiated itself by designing its own switchmode power supply. Let's see if that brings something to the party.
NAD M23 Amplifier Measurements
Let's start with our usual 4 ohm dashboard using XLR input:
We get slightly higher gain than reference design but that seems to have cost us a bit in noise, knocking down SINAD a couple of dBs. Strangely, we get that back partially by using RCA input:
Using an average of 102 dB SINAD, the M23 breaks into our top lowest noise+distortion amplifiers ever tested:
Noise performance is still excellent:
Frequency response is flat and load independent which is what we want to see:
Multitone test shows vanishingly low distortion:
New 19+20 kHz test runs at higher amplitude than Multitone so shows higher distortion spikes:
Crosstalk is extremely good:
Let's get into our power measurement and see if the custom power supply is doing us some good:
We definitely have more power than the reference which is a great thing. I also like the conservative and accurate power specifications.
Transfer function gets a bit uneven at higher frequencies but calms way down by 1 KHz:
The power supply seems to be juicing up the 20 Hz response.
So far our tests have been with resistive loads of 4 and 8 ohm. Let's add reactive (capacitive/inductive) load into the equation including going down to 2 ohms:
Wow, this thing is so load independent! I don't think I have tested an amplifier this good so far.
The amplifier is stable on power on:
Pop on is likely inaudible but you might hear something when you power it down (all done with the soft on/off control):
Couldn't figure out why the noise level was higher after I turned it off for the second time. Maybe it takes a while to drain down to nothing. It is not consequential though.
Conclusions
NAD shows how to take a standard design and make it its own with value added on enclosure, and custom power supply. The latter adds good bit more short term power to the amplifier which in my opinion is quite a bit more important than a bit of noise performance that is lost. You pay for this but remember the cost is that of the retail so margins are baked in for retailers.
I am happy to recommend the NAD M23 stereo amplifier. It is a job well done.
----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/