NAD M23 Stereo Amplifier Review

[Jukka]

All speakers, up to at least 15" bass drivers, have some sort of bass boosting in form of EQ in the crossover or the driver itself is tuned for lower extension (hence lower sensitivity). This boosting takes a lot of power, especially with small drivers. So even if the speaker or driver is rated at 90 dB/W/m @ 1 kHz, the bass will need a lot more juice to play loud.

 

[musicforcities]

"Pulse Width Modulation (PWM) is a fancy term for describing a type of digital signal"

https://learn.sparkfun.com/tutorials/pulse-width-modulation/all

Little late to party but, i am linking to a video I have found the clearest explanation of nyquist-Shannon for non engineer types. At least for me, it was the first time I really “got” what was going on (and why ladder based dacs can’t compete with delta sigma):

 

[antcollinet]

Little late to party but, i am linking to a video I have found the clearest explanation of nyquist-Shannon for non engineer types. At least for me, it was the first time I really “got” what was going on (and why ladder based dacs can’t compete with delta sigma):

Looking at that now.

Have you also seen Monty? A fantastic demo of similar, debunking the myth of stair steps, and demoing the impact of reduced bit depth (Increased noise floor) and how to minimise the audibility of that through dithering.

 

[Julf]

Have you also seen Monty? A fantastic demo of similar, debunking the myth of stair steps, and demoing the impact of reduced bit depth (Increased noise floor) and how to minimise the audibility of that through dithering.

Indeed. Unfortunately neither addresses the common misconception that PWM is per se a digital signal.

 

[antcollinet]

Indeed. Unfortunately neither addresses the common misconception that PWM is per se a digital signal.

True - but that is because they are not trying to. They are both discussing PCM digital encoding.

The quoting of @anarchist 's quote above is not really relevant to the reply. (or vice versa)

 

[Julf]

True - but that is because they are not trying to. They are both discussing PCM digital encoding.

The quoting of @anarchist 's quote above is not really relevant to the reply. (or vice versa)

Indeed. That is why I was a bit surprised by the quote - quoting erroneous (or over-simplified) stuff without countering it is not useful.

 

[antcollinet]

Indeed. That is why I was a bit surprised by the quote - quoting erroneous (or over-simplified) stuff without countering it is not useful.

It doesn't help that PWM and PCM both encode/represent an analogue signal and only differ by one letter in the acronym.

I've also mixed them up in the past.

 

[musicforcities]

Indeed. That is why I was a bit surprised by the quote - quoting erroneous (or over-simplified) stuff without countering it is not useful.

I’m was just trying to tie my post back to something that had occurred earlier in the thread. That’s all.

 

[Julf]

I’m was just trying to tie my post back to something that had occurred earlier in the thread. That’s all.

Fair enough, it was just a slightly unfortunate choice of message.

 

[EJ3]

Would it be possible to measure the idle power consumption?

Admittedly, I might be the only one interested in this, since my thread on the subject did not get much traction. But usually it is not information that can be found in the specifications, and since many of these power amplifiers perform similarly, it could be a deciding factor.

Stable at turn on: So why would someone leave it idling 27/7 in case they wanted to use it?
I am curious.

 

[EJ3]

The concept of having extra headroom is bullshit. More power = more loudness. That’s it. In low volumes having a high power amp is useless

And I would play at low volumes: WHY?
I own a single house on a 3/4 acre piece of land so that I won't disturb my neighbors by anything that I am doing.

 

[EJ3]

If you record the idle energy usage with Kill-a-watt for many popular amps you will find idle power consumption is a large portion of the power consumed. Below are some examples:

1. The Buckeye Purifi uses 14W while idle and 14.5W is all that's required to power the Revel F328BE to 75dB only 1/2 a watt difference. That's a decent sound level for many uses. You start to realize the power use while idle can be close to the same as with background music level use.

2. Buckeye NC502MP uses 23W while idle. 24W takes the F328Be to 81dB.

3. Monolith 7x200 uses 140W while idle. It rises to 185W with the Denon 4700 volume at 65.

4. Denon 4700 uses 138W while idle. At a volume of "65" energy use increases to 185W in stereo or 200W with Auro-3D. If you configure the 4700 in pre-amp only mode (no internal amps available) energy use drops to 46W no matter what volume or speaker configuration is used.

Some may think these devices use a lot less energy while idle but that's not what testing shows.

Even so, I can use 400W for an hour and it's still less than 25 cents if I use it during low power times. As long as I turn off my gear when not running it's not a big deal. However, if I was leaving amps on all day thinking they were auto shutting off efficiently then the phantom power drain could be significant depending on the actual energy draw. Only testing would show the true power use.

I still want to know why someone would want to leave it on all the time?
I do have a few pieces of gear that leaving them on is more convenient (because if you don't, they loose all their settings, which causes one to have to reset them).
But there is no reason, whatsoever, that I can see to leave this unit on.

 

[EJ3]

It has been literally decades since "Made in China" had anything to do with a product's quality.

Do you live there? My son does and has (he was born & raised there).
I can say that they can make (and do) just as shoddy gear (for longevity) as anyone else.
Which is why we have sites like this:
To let us know which products from anywhere meet the standards that they should. (including longevity).
But, it sounds to me, as if you do
NOT
have an impartial outlook
But instead
HAVE AN AGENDA.
Enjoy your
BIASES,
And have a good day.

 

[EJ3]

Still you don’t need 100s of watts if you look at a McIntosh power amps at reasonable levels, it doesn’t even cross 10 watts !!

blanket statement. Doesn't include the use cases of others.
I am guessing that I could never live in your USE CASE.

I have a small 18 watt a channel system (that is what it actually is at ratted distortion 8 Ohms.
In the master bedroom, (yes, with ear plugs), I can get a 112 DB sound level (because of some very efficient speakers).
I have, in the far distant past, put this system in the open floor space design living room with a cathedral ceiling,
formal dining room that can only seat 10 (unless you put the tables leaf in), as well as the kitchen and breakfast area.
I put this same system there and it gets driven into clipping before getting to 70 DB.
Which is why there is a system that has 2 passive subs there being driven by a 800 watt a channel (4 OHM sub setup.
Each of the main channels has a bridged mono amp putting out 1000+ watts into 4 Ohms.
I do not have a volume issue there.

 

[dogmamann]

blanket statement. Doesn't include the use cases of others.
I am guessing that I could never live in your USE CASE.

Amazing

 

[SuicideSquid]

Do you live there? My son does and has (he was bon & raised there).
I can say that they can make (and do) just as shoddy gear (for longevity) as anyone else.
Which is why we have sites like this:
To let us know which products from anywhere meet the standards that they should. (including longevity).
But, it sounds to me, as if you do
NOT
have an impartial outlook
But instead
HAVE AN AGENDA.
Enjoy your
BIASES,
And have a good day.

 

[EJ3]

As dogmamann said: Amazing

 

[Drew]

I am probably asking in the wrong place.

Do M23 or equivalent users feel the music is too clean or too sterile?

I am thinking this neutral may make you want to put on jogging sneakers and go away. I am obviously talking from someone who mixes and matches single use stereo components. Measurements make me roll my eye with missing the point,

 

[Julf]

I am probably asking in the wrong place.

Do M23 or equivalent users feel the music is too clean or too sterile?

I am thinking this neutral may make you want to put on jogging sneakers and go away. I am obviously talking from someone who mixes and matches single use stereo components. Measurements make me roll my eye with missing the point,

Are you sure you are on the right forum? If it is "warmth" (distortion, noise and coloration) you want, I suggest one of the many vintage gear forums.

 

[jimbones]

Are you sure you are on the right forum? If it is "warmth" (distortion, noise and coloration) you want, I suggest one of the many vintage gear forums.

Are you sure you are on the right forum? If it is "warmth" (distortion, noise and coloration) you want, I suggest one of the many vintage gear forums.

I have the M23 and I can say that it is absolutely NOT sterile sounding. However, I do have a tube preamp. It sounds glorious.