NAD M23 V2 vs. McIntosh 312 vs. Pass Labs X150.8

[Hue Man]

Hi Guys.
I'm creating my retirement/end game system and would like some input. I'm currently at the drywall stage down in the basement so the purchase decision is months off and I intend to listen to each before my decision (maybe even in-home if I can swing it). Your input would be greatly appreciated.

The Room:
19'8" x 14'8 with a 6'10" suspended ceiling (I know) and cement floors with a rug. There will be room treatments (including Rockwool in the ceiling).

The Gear I currently have:

1. NAD M66 https://www.crutchfield.com/p_745M66/NAD-Masters-Series-M66.html
2. PS Audio Aspen FR-20s https://www.psaudio.com/products/aspen-fr20-loudspeaker/
3. 2 KEF KC62 https://www.crutchfield.com/S-WMZopu6kcSr/p_991KC62B/KEF-KC62-Carbon-Black.html

The Options:

1. McIntosh MC312 https://www.mcintoshlabs.com/products/amplifiers/MC312
2. NAD M23 V2 https://www.crutchfield.com/p_745M23V2/NAD-Masters-Series-M23-V2.html
3. Pass Labs X150.8 https://www.moon-audio.com/products/pass-labs-x150-8-amplifier

My currents thoughts:

McIntosh -

My favorite power amp brand. (Have the MC152 and love it.)
The warmness might go well with the M23 and Aspens.
Love the look, but not a match with the M23.
I can get it a from local dealer (stereo dealer) who I used to walked by twice a day during college. (Go Badgers) I got the MC 152 from him.
The NAD and the MC have the best shot of being home demoed.

NAD M23 V2 -

Matches the best with the M66 (including stylistically).
Maybe too detailed when combined with the M23 and Aspens.
Local dealer; the NAD and the MC have the best shot of being home demoed.
Measures about as well as anything.

Pass Labs X150.8

I hear Nelson Pass is a genius.
Class A up to around 15 Watts (Which may be all I need) but about 300 total watts into 4 ohms. Have not heard Class A yet, but I like the idea.
Closest dealer in Chicago (about 2.5 hrs away).
Doubt I'll get a home demo.
Doesn't measure well. (HERE IS WHERE THE FUN BEGINS.) I believe that measurements matter if you can hear them. They also matter if you can't hear them (but a little bit less). If you hear
something that you can't pass a blind A/B test on, I guess placebos are a nice thing if they don't cost too much.
Might match well with the NAD M66/Aspen combo.
I like the look, just wish it had real meters

Thanks for all of the input.

 

[DVDdoug]

McIntosh -

My favorite power amp brand. (Have the MC152 and love it.)
The warmness might go well with the M23 and Aspens.

I'm sure the McIntosh is "perfect" and not "warm" or anything like that. i.e. A "straight wire with gain". Heck, even in the tube days, McIntosh was known for perfect sound.*

The other amps are likely audibly transparent too. With modern electronics it's cheap and easy to make something better than human hearing. (Power still costs money, but good-quality class-D power is very economical.)

So my only real advice is, don't by an amplifier for it's "sound quality/character". ...That's for speakers (and headphones).

Class A up to around 15 Watts (Which may be all I need) but about 300 total watts into 4 ohms. Have not heard Class A yet, but I like the idea.

Class-A isn't the "best", it was simply the 1st way to make an amplifier. When I was growing up in the 1960s my AM tube radio had a class-A amplifier, as well as our TV and car radios etc. Class A/B requires one more tube, transistor, or MOSFET so you'd only find class A/B in more expensive and more powerful hi-fi equipment. Class-A is energy inefficient Class-D requires a LOT more electronics but it's nearly 100% efficient and with all of the electronics in a chip it's more economical per-watt. And since it doesn't have to dissipate as much heat it can be smaller and lighter.

I hear Nelson Pass is a genius.
Class A up to around 15 Watts

So basically class A/B, except that class A/B is usually only "class-A" up to around 1 Watt.

They also matter if you can't hear them (but a little bit less).

IMO - It's best to think logically and economically. If "A" has 0.01% distortion and "B" has 0.0001% distortion, how much more would you pay for the lower distortion. Or, would you want the lower distortion amp if it was ugly or if you had to wait a couple of months for delivery, or if was less reliable?



* Somebody gave me a McIntosh tube amp in the 1970's. It sounded perfect but it was mono so I eventually gave it away to someone else.

 

[LumiAudioNut]

Hi Guys.
I'm creating my retirement/end game system and would like some input. I'm currently at the drywall stage down in the basement so the purchase decision is months off and I intend to listen to each before my decision (maybe even in-home if I can swing it). Your input would be greatly appreciated.

The Room:
19'8" x 14'8 with a 6'10" suspended ceiling (I know) and cement floors with a rug. There will be room treatments (including Rockwool in the ceiling).

The Gear I currently have:

1. NAD M66 https://www.crutchfield.com/p_745M66/NAD-Masters-Series-M66.html
2. PS Audio Aspen FR-20s https://www.psaudio.com/products/aspen-fr20-loudspeaker/
3. 2 KEF KC62 https://www.crutchfield.com/S-WMZopu6kcSr/p_991KC62B/KEF-KC62-Carbon-Black.html

The Options:

1. McIntosh MC312 https://www.mcintoshlabs.com/products/amplifiers/MC312
2. NAD M23 V2 https://www.crutchfield.com/p_745M23V2/NAD-Masters-Series-M23-V2.html
3. Pass Labs X150.8 https://www.moon-audio.com/products/pass-labs-x150-8-amplifier

My currents thoughts:

McIntosh -

My favorite power amp brand. (Have the MC152 and love it.)
The warmness might go well with the M23 and Aspens.
Love the look, but not a match with the M23.
I can get it a from local dealer (stereo dealer) who I used to walked by twice a day during college. (Go Badgers) I got the MC 152 from him.
The NAD and the MC have the best shot of being home demoed.

NAD M23 V2 -

Matches the best with the M66 (including stylistically).
Maybe too detailed when combined with the M23 and Aspens.
Local dealer; the NAD and the MC have the best shot of being home demoed.
Measures about as well as anything.

Pass Labs X150.8

I hear Nelson Pass is a genius.
Class A up to around 15 Watts (Which may be all I need) but about 300 total watts into 4 ohms. Have not heard Class A yet, but I like the idea.
Closest dealer in Chicago (about 2.5 hrs away).
Doubt I'll get a home demo.
Doesn't measure well. (HERE IS WHERE THE FUN BEGINS.) I believe that measurements matter if you can hear them. They also matter if you can't hear them (but a little bit less). If you hear
something that you can't pass a blind A/B test on, I guess placebos are a nice thing if they don't cost too much.
Might match well with the NAD M66/Aspen combo.
I like the look, just wish it had real meters

Thanks for all of the input.

Hi Hue Man,

Welcome to the forums.

Since a review with measurements for the Pass Labs X150.8 are hard to come by, I thought I would share one:

https://www.alpha-audio.net/review/review-pass-labs-x150-8-entry-level-pass-or-is-it/4/

Interestingly, the measurements shows that total harmonic distortion improved by a not completely insignificant amount after the amplifier had “broken in” over a period of 2 months. I’ve seen this behavior before; usually in amplifiers with a significant amount of class A output. Some people will say that amplifier break in is a myth (it usually is!), but it isn’t always.

There was also a 2 to 3 watt improvement in output power (also proven by measurements).

 

[Hue Man]

I'm sure the McIntosh is "perfect" and not "warm" or anything like that. i.e. A "straight wire with gain". Heck, even in the tube days, McIntosh was known for perfect sound.*

The other amps are likely audibly transparent too. With modern electronics it's cheap and easy to make something better than human hearing. (Power still costs money, but good-quality class-D power is very economical.)

So my only real advice is, don't by an amplifier for it's "sound quality/character". ...That's for speakers (and headphones).


Class-A isn't the "best", it was simply the 1st way to make an amplifier. When I was growing up in the 1960s my AM tube radio had a class-A amplifier, as well as our TV and car radios etc. Class A/B requires one more tube, transistor, or MOSFET so you'd only find class A/B in more expensive and more powerful hi-fi equipment. Class-A is energy inefficient Class-D requires a LOT more electronics but it's nearly 100% efficient and with all of the electronics in a chip it's more economical per-watt. And since it doesn't have to dissipate as much heat it can be smaller and lighter.


So basically class A/B, except that class A/B is usually only "class-A" up to around 1 Watt.


IMO - It's best to think logically and economically. If "A" has 0.01% distortion and "B" has 0.0001% distortion, how much more would you pay for the lower distortion. Or, would you want the lower distortion amp if it was ugly or if you had to wait a couple of months for delivery, or if was less reliable?



* Somebody gave me a McIntosh tube amp in the 1970's. It sounded perfect but it was mono so I eventually gave it away to someone else.

Thanks for the input.

Some people say Class A sounds better despite the higher distortion. I hope to listen to it and wonder if I can hear the difference.

 

[Descartes]

Thanks for the input.

Some people say Class A sounds better despite the higher distortion. I hope to listen to it and wonder if I can hear the difference.

Let us know

 

[Hue Man]

This will be a couple of months. Wall insulation up. Drywall, ceiling insulation, paint floor and suspended ceiling next. Axpona 2026 Chicago in April will be my first chance to easily hear the Pass Labs without driving to downtown Chicago.