NAD C658 Streaming DAC Review

[Paulius]

This too was at one point on my short list of "all in one streamers", but alas maybe the NAD Master M33 will do better for $5,000?
https://nadelectronics.com/nad-mast...purifis-ultra-quiet-amplification-technology/
View attachment 54659

Hello. I can confirm Sub Out of Nad M33 is very weak. I even sold my SVS SB1000 and bought SB3000 but low sub out remained here as well. However, I have replaced cheap rca cable to Supra Sublink rca cable, ir made some positive difference. Anyway, I need to listen to the music on quite loud volume to hear the subwoofer (if no EQ is used). Shame on NAD circuit designers who decided to go with 1.1V output on SubOut ports.

 

[SIY]

However, I have replaced cheap rca cable to Supra Sublink rca cable, ir made some positive difference.

Unlikely that it made any difference. But what the world needs is a flat gain pre (I have mine set for 6dB gain) to go between the NAD sub outputs and the subs' inputs. No idea why NAD hasn't changed this.

 

[restorer-john]

No idea why NAD hasn't changed this.

Changing a resistor value in the feedback loop of the opamp driving the sub output is a terribly expensive thing...

 

[terfenol-D]

I currently run my Apple TV to my TV via HDMI. I then run an optic cable to my C658 for sound. Would there be any benefit to HDM-2 module and running my ATV -> C658 -> TV all via HDMI? I don’t anticipate adding another video source so don’t really need the HDMI switching.

Just following up on this - I have a bit of a sync issue during TV shows running sound via optic out. I have played with the sync delay but it starts at 50 ms for some reason (I’m assuming for Dirac processing delay???). Any idea if the HDMI module would improve things or if provide any other benefit? Thanks.

 

[Sparkles]

I just received the NAD C658 and was instantly disappointed that the sub out practically muted my SB3000. I've found relief in the SB's parametric EQ settings which allowed me to increase the sub up to 6db. I settled on 4.5 db and am happy for now.

Very glad you posted this. You have solved my SW issue. I have the small SB1000pro.

Now to redo Dirac which I have to anyway since in upgrading to towers I ran Dirac with a somewhat noisy air conditioner and the result was... rubbish.

 

[tbokris]

Checking in with this thread, am I correct in thinking the c658 isn't very good still and issues havent been fixed?

 

[terfenol-D]

Checking in with this thread, am I correct in thinking the c658 isn't very good still and issues havent been fixed?

I like the one I have.

 

[LuvTheMusic]

Checking in with this thread, am I correct in thinking the c658 isn't very good still and issues havent been fixed?

Well, you are going to get a lot of people questioning your basic assumption that the 658 "isn't very good."

So far as I can see, the "not good" idea is based on two items in the original review: (1) Amir could not get the unit to lock on the incoming clock and (2) the SINAD is relatively poor.

However,
(1): The review unit was "refurbished" of unknown provenance (unlikely to be refurbished by the manufacturer, as they do not sell refurbished units directly), so it's impossible to say if it was defective or broken. Moreover, if there indeed was an issue, there have been multiple firmware updates since the review, so the problem, if it indeed existed, may have been fixed.

(2): The SINAD is not world class by any means, and Amir says that this performance is "unacceptable in a high priced device like this", But many people think that the feature set fully justifies the price so that the unit is not particularly "high priced"...and is a SINAD of 90 or so is audible anyway?

Several forum participants have reported that they are pleased with the 658. Personally, I had one and liked it a lot. I sold it to a friend who has a sophisticated system and he likes it as well. My replacing it had nothing to do with its performance.

 

[tbokris]

I like the one I have.

Thanks for letting me know. It's good to hear both sides

 

[tbokris]

Well, you are going to get a lot of people questioning your basic assumption that the 658 "isn't very good."

So far as I can see, the "not good" idea is based on two items in the original review: (1) Amir could not get the unit to lock on the incoming clock and (2) the SINAD is relatively poor.

However,
(1): The review unit was "refurbished" of unknown provenance (unlikely to be refurbished by the manufacturer, as they do not sell refurbished units directly), so it's impossible to say if it was defective or broken. Moreover, if there indeed was an issue, there have been multiple firmware updates since the review, so the problem, if it indeed existed, may have been fixed.

(2): The SINAD is not world class by any means, and Amir says that this performance is "unacceptable in a high priced device like this", But many people think that the feature set fully justifies the price so that the unit is not particularly "high priced"...and is a SINAD of 90 or so is audible anyway?

Several forum participants have reported that they are pleased with the 658. Personally, I had one and liked it a lot. I sold it to a friend who has a sophisticated system and he likes it as well. My replacing it had nothing to do with its performance.

Thanks for the comments. Good to know. I don't know what SINAD sounds like and what it would be if I heard it (I looked it up). I too am looking at the NAD for the unique set of features it has. Looking at the Lyngdorf TDAI1120 also now, which is £500 more but does the same things I want the NAD to do.

 

[steadilyfred]

Looking at the Lyngdorf TDAI1120 also now, which is £500 more but does the same things I want the NAD to do.

The Lyngdorf TDAI-1120 is an integrated amplifier. The NAD C 658 is not.

 

[tbokris]

The Lyngdorf TDAI-1120 is an integrated amplifier. The NAD C 658 is not.

Good point, but for my needs, using the pre outs on the Lyngdorf, it can do what I want the NAD C 658 to do in terms of getting room correction into a system

 

[steadilyfred]

Good point, but for my needs, using the pre outs on the Lyngdorf, it can do what I want the NAD C 658 to do in terms of getting room correction into a system

If you're looking for something comparable to the C 658, then the miniDSP SHD seems like an obvious consideration to me.

SHD

Roon Ready network audio streamer with Dirac Live® room correction, miniDSP audio toolbox for subwoofer integration and multiway speakers, Volumio music player, Audiophile 32-bit converters, 450MHz Sharc DSP processor

www.minidsp.com

 

[tbokris]

If you're looking for something comparable to the C 658, then the miniDSP SHD seems like an obvious consideration to me.

SHD

Roon Ready network audio streamer with Dirac Live® room correction, miniDSP audio toolbox for subwoofer integration and multiway speakers, Volumio music player, Audiophile 32-bit converters, 450MHz Sharc DSP processor

www.minidsp.com

Yes I had looked at that. The Mini DSP SHD doesn't have a phono stage, and i was planning on an external phono stage, but apparently the Lyngdorf one is quite good from what I've read.

 

[offtrack]

I think you will enjoy the C658. Dont bother with the HDMI card. There are not IR codes to select the HDMI inputs so its basically useless IMO.

Make sure to come back and let us know what you think!

Not correct.
I've recently purchased a MDC HDM-2 which is fitted to a C368, but instructions are same for the C658.


The remote can access 9 inputs.
When the HDMI card is added, the 9th remote position is allocated to HDMI1.
To access the other inputs you need disable a couple of unused inputs.

This is described on the first page of the remote control information (page 10) in the manual.

• Under “MDC HDM 2 Installed with some Sources disabled” column below, Optical 2 (OPT 2) and PHONO Sources were disabled so that HDMI 1, HDMI 2 and HDMI 3 Sources can be assigned and directly selectable via SR 9.

 

[Brian6751]

Not correct.
I've recently purchased a MDC HDM-2 which is fitted to a C368, but instructions are same for the C658.


The remote can access 9 inputs.
When the HDMI card is added, the 9th remote position is allocated to HDMI1.
To access the other inputs you need disable a couple of unused inputs.

This is described on the first page of the remote control information (page 10) in the manual.

It was correct when I posted that three years ago... Glad they explain how to make it work now.

 

[offtrack]

It was correct when I posted that three years ago... Glad they explain how to make it work now.

My bad. Checking back documentation was added in v7 of the C658 manual, dated 2022.

Prior to that there is only a note in the remote docs:

7 SOURCE: Toggle through the source input selections. If the optional MDC modules are
installed, the source selections will include the sources incorporated in the applicable modules.

This is a 2019 version of the C658 manual, and also appears in a C386 manual dated 2016 so there was always some ability to access MDC inputs from the IR remote.
The NAD iOS app hasn't been updated since 2017, and can access the HDMI card inputs, and only displays enabled inputs, so it looks like the functionality has been there from introduction.

But as you say the documentation on how to make the inputs accessible via the numeric keys on the remote was missing prior to 2022.

 

[steadilyfred]

Finally! The latest BluOS firmware update (3.20.52) has added volume limits for the C 658.

 

[sharock]

Finally! The latest BluOS firmware update (3.20.52) has added volume limits for the C 658.

Unbelievable it took so long!

I use % and the limits are specified in dB. Not the end of the world. Just means changing the display to convert first.

 

[Flussgott]

New Update!
BluOS 3.20.53. Released June 6, 2023.
• Improvements for NAD C658 digital inputs
• This release applies to NAD C658 only