NAD C 298 Power Amplifier With Purifi Eigentakt Amplification

[lalit09]

I just noted that the power supplies in the M33 and the C298 are very similar, if not identical:
View attachment 87278
C298 top, M33 bottom.

Wow they seem identical...

 

[TomJ]

NAD SMPS, Jianghai caps...

Thank you @StefaanE for the helpful follow-up in another thread:
FWIW, a German forum (Igorslab.de) had the following to say about Jianghai: Anyone who'd think the supplier is one of those Chinese junk manufacturers would be completely wrong. Jianghai is one of the oldest Chinese manufacturers and emerged from a former supplier to the People's Army. In addition they purchased the capacitor production line from Hitachi, so all-in-all, you get Hitachi quality at a fair price. The components don't fear comparison with those from Chemicon.
https://www.audiosciencereview.com/...le-electrolytic-capacitors.17032/#post-550829

 

[Michael42]

Hi,
I read this discussion with a lot of interest.
I'm currently thinking about a combination of NAD C658 and NAD 298. I would probably get KEF R7 as speakers.
What do you think about this combination?

The NAD M33 also looks nice. But the price difference is quite big and my wife is not happy about this.
Do you think the M33 really is that better then NAD C658 and NAD 298?
What is the big difference despite a better look and the display? Does it sound that much better?

Would it be possible to add an AVR Receiver and use the KEF speakers over the NAD systems?
What would be the best way to do that? Would I need the NAD MDC HDMI Module for this?

Many thanks for your opions,
Michael

 

[Michael42]

Hi,
sorry if I may ask a stupid question as I'm new to hifi.
As I understand it a combination of C658+C298 and the M33 provide a similarset of features?
For example both provide BluOS Multiroom streaming, Dirac and Purify Technology for the amp.

The biggest difference for me is that M33 is a "all-in-one" amp of the higher master series with a nice touchscreen, a good look and a much higher price.
Of course the specifications are also better. But I'm not sure if this is worth the price difference?

I read a comment from John Darko ( https://darko.audio/2020/09/nad-preps-purifi-eigentaktd-c-298-power-amplifier/ )
"If we add NAD’s C 658 streaming pre-amplifier (to the C 298) for US$1650, we get an Eigentakt-based amplifier system with BluOS streaming, MM phono staging and Dirac Live Lite for US$3650. Add the full-frequency Dirac Live for an extra US$99 and we arrive at a total of US$3750 — a full US$1250 less than the US$5000 Masters M33. That’s interesting for those who can do without the latter’s touchscreen, balanced inputs and MC phono staging. "

Thanks,
Michael

 

[ririt]

Hi,
sorry if I may ask a stupid question as I'm new to hifi.
As I understand it a combination of C658+C298 and the M33 provide a similarset of features?
For example both provide BluOS Multiroom streaming, Dirac and Purify Technology for the amp.

The biggest difference for me is that M33 is a "all-in-one" amp of the higher master series with a nice touchscreen, a good look and a much higher price.
Of course the specifications are also better. But I'm not sure if this is worth the price difference?

I read a comment from John Darko ( https://darko.audio/2020/09/nad-preps-purifi-eigentaktd-c-298-power-amplifier/ )
"If we add NAD’s C 658 streaming pre-amplifier (to the C 298) for US$1650, we get an Eigentakt-based amplifier system with BluOS streaming, MM phono staging and Dirac Live Lite for US$3650. Add the full-frequency Dirac Live for an extra US$99 and we arrive at a total of US$3750 — a full US$1250 less than the US$5000 Masters M33. That’s interesting for those who can do without the latter’s touchscreen, balanced inputs and MC phono staging. "

Thanks,
Michael

The C658 was tested by Amir and the results were disappointing especially regarding the DAC performances. The M33 was measured @johnatkinson for stereophile (availalbe on the web site). Since @johnatkinson is also a ASR member, I am sure he will be able to comment their respective performances especially on the digital side.

 

[Michael42]

The C658 was tested by Amir and the results were disappointing especially regarding the DAC performances. The M33 was measured @johnatkinson for stereophile (availalbe on the web site). Since @johnatkinson is also a ASR member, I am sure he will be able to comment their respective performances especially on the digital side.

This is very interesting. I saw that C658 has "ESS Sabre D/A-Wandler with 24 Bit / 192 kHz Auflösung" while M33 has "32 Bit/384 kHz ESS Sabre D/A-Wandler". Does someone has more information?

Would you guys see a problem with buying an all-in one solution instead of separate modules?
My old Hifi system is about 30 years old and it still works despite of some minor things.
I hope that nowadays hifi components are still reliable in long term use (and can be used without a cloud application).

Regards,
Michael

 

[ririt]

This is very interesting. I saw that C658 has "ESS Sabre D/A-Wandler with 24 Bit / 192 kHz Auflösung" while M33 has "32 Bit/384 kHz ESS Sabre D/A-Wandler". Does someone has more information?

Would you guys see a problem with buying an all-in one solution instead of separate modules?
My old Hifi system is about 30 years old and it still works despite of some minor things.
I hope that nowadays hifi components are still reliable in long term use (and can be used without a cloud application).

Regards,
Michael

I just saw in another thread that Amir has almost completed the test of the M33. it will be released in the coming days. Let’s see what is the result...

 

[CDMC]

The C658 was tested by Amir and the results were disappointing especially regarding the DAC performances. The M33 was measured @johnatkinson for stereophile (availalbe on the web site). Since @johnatkinson is also a ASR member, I am sure he will be able to comment their respective performances especially on the digital side.

It is worth noting that "disappointing" for a DAC means it was a 90db sn ratio, still close to the limits of 16 bit audio and likely an inaudible difference in sound from the best measuring DACs.

 

[CDMC]

Hi,
I read this discussion with a lot of interest.
I'm currently thinking about a combination of NAD C658 and NAD 298. I would probably get KEF R7 as speakers.
What do you think about this combination?

The NAD M33 also looks nice. But the price difference is quite big and my wife is not happy about this.
Do you think the M33 really is that better then NAD C658 and NAD 298?
What is the big difference despite a better look and the display? Does it sound that much better?

Would it be possible to add an AVR Receiver and use the KEF speakers over the NAD systems?
What would be the best way to do that? Would I need the NAD MDC HDMI Module for this?

Many thanks for your opions,
Michael

Michael,

A suggestion. Start a new thread asking for suggestions and include the following information:

• System configuration (i.e. just streaming, or also sound for movies from a tv, analog inputs (i.e. turntable)).
• System use (music only, movies only, combination).
• Room size.
• Current equipment.
• What you don't like about your current system.
• Budget- Please give speaker budget and a front end budget as well as a total budget (one that keeps your wife reasonably happy).

You may want to post it in the beginner or general forum. Excellent sounding systems can be assembled for less than $1,000, but with all systems (unless your budget it unlimited) there are tradeoffs and without the above information we are shooting in the dark about recommendations that are best for YOU. Don't be surprised, but the recommendations will likely suggest spending less on a pre-amp/streamer/dac/amp than you are currently looking at and more on speakers and/or adding subwoofers. Once you get to the level that the electronics are competently designed, there is little, if any performance difference among them (i.e. in 99.9% of cases, there will be no audible improvement going from a Hypex NC502 based amplifier, about $750 to something more expensive). Contrast this with spending $1,000 to add a pair of subwoofers which can make a huge difference in the sound.

 

[Michael42]

Thank you. I created this thread:
Advice for good living room sound system (streaming, multi room)

I´m also looking forward to the test of the NAD M33.

Regards,
Michael

 

[lappy]

Does anyone know if the Rel subwoofer high level connection considerations/recommendations apply to the C298?
https://relsupport.zendesk.com/hc/en-us/articles/115004486607-Class-D-Amp-Connection-Methods
I.e do the C298 "reference to 10-15 volts ABOVE ground"? (I have no idea what that means).

 

[Chippyboy]

Does anyone know if the Rel subwoofer high level connection considerations/recommendations apply to the C298?
https://relsupport.zendesk.com/hc/en-us/articles/115004486607-Class-D-Amp-Connection-Methods
I.e do the C298 "reference to 10-15 volts ABOVE ground"? (I have no idea what that means).

You can assume that they do. Grounding the black speaker connector on any class D amp is a very bad idea indeed. All of the class D amps I know of are balanced. i.e. their negative terminal is not grounded.

So you can try simply connecting the REL's yellow and red wires to left positive and right positive on the amp, and leave the REL black wire disconnected. If that works then great, but if you get hum, then try connecting the REL black wire to the ground connector on the C298. That will almost certainly work fine.

 

[lappy]

You can assume that they do. Grounding the black speaker connector on any class D amp is a very bad idea indeed. None of the class D amps I know of are not balanced. i.e. their negative terminal is not grounded.

So you can try simply connecting the REL's yellow and red wires to left positive and right positive on the amp, and leave the REL black wire disconnected. If that works then great, but if you get hum, then try connecting the REL black wire to the ground connector on the C298. That will almost certainly work fine.

Thank you!

 

[Canth]

Got my C298 yesterday. It goes quite nicely with my C658. However, I have some strange findings
I'm using a trigger cable from de 658 to the 298. This works like a charm. However, if I stop playback on the 658, the 298 eventually (after about an hour, haven't measured how long it takes exactly) goes into standby and I cannot seem to wake it again except by turning the C658 off and on again. I've tried starting the music (according to the front screen I do manage to do that) and upping the volume (after resuming playback on the 658 of course). I've already set the 'auto-sense' switch to low, but that doesn't seem to do anything. Am I correct in my assumption that raising the volume on my C658 should also up the voltage that's being sent to the C298?

Also, while using the balanced inputs, I still get a 'thump' in my speakers when I turn off the C658 (and the trigger turns off the amp). This can be fixed by using the unbalanced inputs. So now I'm using those. I hear no difference in sound quality, but the 'thump' is gone...

 

[lappy]

Got my C298 yesterday. It goes quite nicely with my C658. However, I have some strange findings
I'm using a trigger cable from de 658 to the 298. This works like a charm. However, if I stop playback on the 658, the 298 eventually (after about an hour, haven't measured how long it takes exactly) goes into standby and I cannot seem to wake it again except by turning the C658 off and on again. I've tried starting the music (according to the front screen I do manage to do that) and upping the volume (after resuming playback on the 658 of course). I've already set the 'auto-sense' switch to low, but that doesn't seem to do anything. Am I correct in my assumption that raising the volume on my C658 should also up the voltage that's being sent to the C298?

Also, while using the balanced inputs, I still get a 'thump' in my speakers when I turn off the C658 (and the trigger turns off the amp). This can be fixed by using the unbalanced inputs. So now I'm using those. I hear no difference in sound quality, but the 'thump' is gone...

This does not seem right. Turning the C658 on/off with at trigger cable attached to the C298 should trigger the C298 to turn on/off. You should contact the dealer. It is by the way a damn shame that the C298 does not have auto off without trigger cable (it only has auto on).

 

[Canth]

Thanks. In my case it does seem to do auto off, it just never turns on again
I've also tested without the trigger cable. The amp wakes up the first time I put on music with the C658. If I stop the music the amp also powers down (the C298, the C658 always is on, just on pause) and it only powers on again if I use the switch in the back.
It seems my C298 is broken in a weird way...

 

[lappy]

Thanks. In my case it does seem to do auto off, it just never turns on again
I've also tested without the trigger cable. The amp wakes up the first time I put on music with the C658. If I stop the music the amp also powers down (the C298, the C658 always is on, just on pause) and it only powers on again if I use the switch in the back.
It seems my C298 is broken in a weird way...

Wait what? Your C298 has some sort of auto off without trigger cable? That's not even supposed to be a feature according to NAD.
Mine manages to do auto on with the unbalanced input. I have had it since the release and I still do not understand why they didn't implement the most important part of auto on/off, namely auto off. It is mandated by EU law I think. Auto on is just for convenience.

 

[Insomniac]

Hi all,

Currently running a Rotel combo RC/RB 1590 and using the C658 as a bluesound streamer. And since i already have the C658 this C298 looks interesting. However no reviews on the C298 bridged can be found anywhere, and thats what i am really curious about: performance in bridgemode to feed my B&W 702S2.

Wonder how it compares to my Rotel.

 

[lalit09]

Got my C298 yesterday. It goes quite nicely with my C658. However, I have some strange findings
I'm using a trigger cable from de 658 to the 298. This works like a charm. However, if I stop playback on the 658, the 298 eventually (after about an hour, haven't measured how long it takes exactly) goes into standby and I cannot seem to wake it again except by turning the C658 off and on again. I've tried starting the music (according to the front screen I do manage to do that) and upping the volume (after resuming playback on the 658 of course). I've already set the 'auto-sense' switch to low, but that doesn't seem to do anything. Am I correct in my assumption that raising the volume on my C658 should also up the voltage that's being sent to the C298?

Also, while using the balanced inputs, I still get a 'thump' in my speakers when I turn off the C658 (and the trigger turns off the amp). This can be fixed by using the unbalanced inputs. So now I'm using those. I hear no difference in sound quality, but the 'thump' is gone...

And how do you find the overall audio performance?

 

[VintageFlanker]

Wonder how it compares to my Rotel

Your Rotel 1590 is still one of the best class A/B power amp out there.

You shouldn't notice any audible improvements with Purifi amps, and not that much more power from bridged ones. The only advantage I would see here would be "downsizing" and power consumption.