HiFiRuss71

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This isn't a full review with pictures, description of every technical aspect and all that jazz. I could talk about MQA over Tidal, Sabre DACs (means less than digital filter design anyway) MDC upgrade modules, etc, etc. There are people paid to do that. No; it's a story. It could also fit in the forum for streamers, but that's not the point here.

Divorce changes things. I used to run a 7.1 system with kilowatts of main channel and subwooferage in a 7x5m room detached from the neighbours and reality. Dive far enough back in the reviews section of this august website and you will see pictures of it and the kit that passed through it - 8ft high subwoofers and all.

Those days were gone and for two years I was shacked up mid terrace with frankly less room than was needed for a pair of twin 8" driver loudspeakers and a 14" subwoofer. But the enforced cold turkey did cure me of multichannel. I just didn't miss it, or the slippery slope of upgrades, or the hours of re-EQing 9 speakers every time something was moved or changed.

Time moves on, divorces were settled and money was released. New houses were bought and both the opportunity and means were there to do what I wanted. God bless my new partner in being both a music fan and saying I could buy whatever I wanted, by which she meant she didn't care how large. Get me.

The coffin sized Klipsch Forte IIIs and 100W valve monoblocks may seem a bit leftfield. Nobody who dare enter here forgets them and the amps aside (I first met them in my dealer days in the '90s and have hankered ever since) even I was surprised when I handed over the cash for the speakers. They weren't on the radar beyond idol curiosity, but at first listen I knew I wasn't leaving without them. If you can, do.

I digress; if there was something I missed, it was EQ. Had I not had it, I could have lived without it and always one to refine positioning before just pressing the EQ button, it was a pretty damn satisfying result. But I knew....

The main problem was finding a solution that didn't involve both paying for and then having a pile of redundant channels and processing, plus a shed load of other stuff I no longer need. I also didn't want a solution that went between the Audiolab M-DAC+ and the power-amps. Too much DAC to ADC to DAC conversion for my liking. The other issue was that outside of the very high end AV processors, I'd never heard an EQ system that didn't stuff up mid-range and treble detail when engaged. Anthem's ARC was as close as it came, but even then, I restricted it to below 300Hz to save stifling music.

At the time i was eyeing up purchases, there were only really two pre-amps that caught my eye. The Anthem STR Pre and the just announced NAD C658. Both were in budget (one obviously moreso) and I knew the Anthem would be stellar. But as someone already in the BluOS ecosystem, the thought of reduced box count and increased operational integration was seductive. And Dirac. I played with a full blown version for a few weeks in a Datasat RS20i once and it was awesome.

One problem. Dirac in the C658 was still a future promise of an upgrade and AV is littered with shattered promises. Still, the system wasn't exactly shabby, so I sat it out. Then came word from a reliable source in April that an announcement would be made in May about the date the upgrade would arrive in June. It had arrived as promised in the M10, so there was a precedent for NAD promises being met. Close enough. I bought one.

I was a bit underwhelmed at first. As it and I have settled into each other I began to appreciate the way that it's less sterile nature (than the still remarkable Audiolab M-DAC+ it replaced) makes everything more listenable. It's still highlights the difference between [real] 24/192 and 16/44, but it doesn't savage less than stellar mixes.

A bit rose tinted? Possibly, but then I'm sitting here with valves and horns, so I'm possibly less fussed about technical accuracy than I used to be and more concerned with communication of all of my music, not just test pieces that sparkle.

Then Dirac turned up, as promised "on or around the 10th June". The 13th as it turned out, which makes the cut for an AV promise. Better still, it ain't no flaky 1.1 being released on us public beta testers - It just works; supremely easily after years of effing about with serial cables, 1/60th octave parametric equalisers, clipping input levels and all the other pain that goes with having been an early adopter.

Of course, it was about 0.3 of a second before the techie me ponied up for the full version of Dirac. If you're not going to equalise more than the bass, it's better to know that can if you want to right? More later.

The phone/tablet/PC interface and workflow is so well explained, even the lowliest mouth-breather can't completely stuff it up. It's just the BluOS app with input selection and you toggle between up to five stored Dirac profiles under the players individual settings. People with high sensitivity speakers should note that the default test tone volume is staggeringly LOUD! My speakers a 99dB/W sensitive and I know valve Watts go further but not quite that much further. Reduce the test tone volume to below -50dB on the scale and THEN test the volume levels. Just saying.

To say the end result is transformative would be a small understatement, but one that those of us with a multichannel background will think self explanatory. However, to finally have this level of accuracy, this level of user friendliness in an actual real piece of hi-fi is bloody marvellous. To be able to do absolutely everything from track selection and volume to toggling between different EQ curves all from your phone is another promise finally delivered - That technology will converge and actually make things easier.

To give a hint of what it does to those not used to good EQ; when you turn it on for the first time, you actually think where the hell did everything go? All the performers seemed to shrink and bass disappears. It sounds pathetic, but you need to suspend disbelief and leave it on.

What has happened is that when images snap into focus (to extend a photography metaphor) is that the overall level of brightness goes down and the objects in focus get smaller. The quiet darkness around them fills the gaps, but the sharper, more tightly defined images are locked distinctly in their own space, separated from the background and have greater in dynamic contrast because of it. Because bass is no longer flooding the room, you turn it up and the images grow and the thump is replaced with punch and speed.

You can revisit a measurement and create different versions of it. The C658 will store up to five. Once I'd dialled in sufficient bass lift (default is too flat and NADs .txt curve was a bit too phat and restricted to the non-full Dirac 500Hz max) I uploaded a full range, a below 500Hz (because that's were my bass driver rolls off) and a below 120Hz versions of the filter solution. Memories of great bass but not doing 'its thang' above that lingered from past lowlier EQ implementations lingered in my mind.

I'm now running Dirac full range and there it will stay. It's the real deal.

Russ
 
A great review Russ! I'm looking to get one of these and pairing it with NAD C268 power amp.

I'm surprised there aren't more forum members talking about this product!

There's a monster C658 thread over on the AVSforums site, but aside from your excellent write-up, nothing at all on this forum.

And I'm somewhat surprised What Hi-Fi hasn't done a review yet...
 
Also...out of interest Russ, are you connecting your C658 to your power amp using the XLR Balanced outs? Or the regular single-ended phono/RCA connections?
 
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I think the UK PR was waiting for Dirac to hit before sending out the press samples. That was mid June and there's normally a three month lag between samples going out and publication.

Although I would always use the balanced outputs for preference, my power-amps only have single ended inputs, so that is what I am using.

I'm surprised there isn't more chat about the C658. One, NAD has never been that popular round here and two, people's heads seem to explode when presented with anything less than 7 channels. The Marantz NR-1200 thread is a good example...

Russ
 
I don't know where I got "open-ended" from. I did of course mean single-ended! Post now corrected. It makes sense what you say about waiting for Dirac to be available for the C658 before releasing units to the hi-fi press for review, as it's one of its key selling points.
 
Another happy C658 owner here, with a considerable amount of that happiness being derived from paying for and learning how to use DIRAC live full spectrum.

Similar to Russ, the first time I did my room measurement and turned on DIRAC with their flat/target curve - it completely neutered the sound stage and took all the life / depth out of my system, I was convinced that it was a waste of money.

I ended up reworking how my components were connected (towers via XLR and sub via front pre outs rather than the sub out) as well as spending a ton of time slowly tweaking the target curve in DIRAC.

Depending on the song / master, in some cases you really don't notice much of any difference with DIRAC, in other cases it is a night and day difference.

DIRAC doesn't reduce any of the detail in playback, but it does kind of blend the sound stage into a more fluid and room filling experience. There is less separation and sterility in the music, the sound stage is more velvety and warm, also the sound feels less like it is coming from distinct speakers and more like it is filling the room. One thing it certainly does is reduce the harshness or brightness that seems to be a common complaint about the unit, which I also struggled with until getting DIRAC sorted out.

Anyway, happy to answer any questions if any come up.
 
I think the hardness often talked about, disappeared with 100 or so hours of use. I had to wait a month or so before Dirac was implemented and the NAD was sounding a lot smoother and more open than it did in the first few days, long before Dirac.

Are you using any particular EQ curve.

Russ
 
If you find the more accurate flatter response has too little bass.
This can be improved by by addressing nulls.
Boosting nulls with eq will reduce headroom and compress music.
Reduce nulls by placing speakers right against wall and acoustic absorbers behind speakers.
This should achieve greater accuracy and solid bass.
 
A great review Russ! I'm looking to get one of these and pairing it with NAD C268 power amp.

I'm surprised there aren't more forum members talking about this product!

There's a monster C658 thread over on the AVSforums site, but aside from your excellent write-up, nothing at all on this forum.

And I'm somewhat surprised What Hi-Fi hasn't done a review yet...

Out of curiosity - did you buy the C658 with C268? I am planning to purchase the same combo and I am interested to hear from someone who has tried it. Any thoughts about it?

Thanks in advance!
 
Out of curiosity - did you buy the C658 with C268? I am planning to purchase the same combo and I am interested to hear from someone who has tried it. Any thoughts about it?

Thanks in advance!

I did buy them so that I could take advantage of the Sevenoaks trade-in/trade-up offer that was running through August to early September.

However, I can't set them up as there is some work being done on my lounge that, for various reasons, has fallen behind schedule, so for now they are still in their boxes awaiting the work to be completed before I can set them up!

I will be sure to post my thoughts on here once I've had them for a while...
 
I think the UK PR was waiting for Dirac to hit before sending out the press samples. That was mid June and there's normally a three month lag between samples going out and publication.

Have you seen the recent What Hi-Fi Review? It's also won the award for Best Music Streamer in the £1000-£1500 category (second link). They took their time getting around to it! But great to see a favourable review of it, and to see it win an award too!


 
Can any C658 owners on here confirm if the BluOS app will allow Tidal to be streamed on it via Amazon Alexa commands? Tidal support for Alexa is not currently available in the UK, but I am wondering if it's possible to do via the BluOS app as it supports Alexa and I don't see any mention on the BluOS site of any country restrictions.
 
I did buy them so that I could take advantage of the Sevenoaks trade-in/trade-up offer that was running through August to early September.

However, I can't set them up as there is some work being done on my lounge that, for various reasons, has fallen behind schedule, so for now they are still in their boxes awaiting the work to be completed before I can set them up!

I will be sure to post my thoughts on here once I've had them for a while...

I will probably go for the same. I am convinced that I want different boxes for different functions. Even though the M10 get good review I am certain that I would miss the C658+C268 combo - I am too old school I guess. And the phono stage on C658 doesn't hurt!
 
Anyone own the C658 having the same issues as me in terms of it forgetting everything once it goes to standby?

Loses network shares, usb drives and Amazon music logins once switched off - not impressed as requires a full setup everytime I switch it back on!!! It'll be going back asap.
 
Anyone own the C658 having the same issues as me in terms of it forgetting everything once it goes to standby?

Loses network shares, usb drives and Amazon music logins once switched off - not impressed as requires a full setup everytime I switch it back on!!! It'll be going back asap.

Not with the C368 but I had this issue with the C388, was swapped/repaired twice. Then the screen went. Third time I had to ask to swap to another manufacturer as I'd had enough. Now have a Lumin which far exceeds the NAD in reliability and performance and sound quality, but dosent have DIRAC.
 
Not with the C368 but I had this issue with the C388, was swapped/repaired twice. Then the screen went. Third time I had to ask to swap to another manufacturer as I'd had enough. Now have a Lumin which far exceeds the NAD in reliability and performance and sound quality, but dosent have DIRAC.
Doesn't sound like good news for this one then, assume it's some kind of memory issue which means it goes into 'new' mode whenever I switch it on!! Very annoying!
 
Sorry to hear about the problems with the C388. Maybe you just got a lemon. NAD certain makes quality audio products. A friend of mind owns one and he’s never had an issue with it. I am keeping my fingers crossed since I just bought the NAD C388.
 
Sorry to hear about the problems with the C388. Maybe you just got a lemon. NAD certain makes quality audio products. A friend of mind owns one and he’s never had an issue with it. I am keeping my fingers crossed since I just bought the NAD C388.

They definitely used to, but I've had a C388 and C368 and both have had issues. NAD definitely won't be a brand I'll be revisiting anytime soon thats for sure.
 
Another happy C658 owner here, with a considerable amount of that happiness being derived from paying for and learning how to use DIRAC live full spectrum.

Similar to Russ, the first time I did my room measurement and turned on DIRAC with their flat/target curve - it completely neutered the sound stage and took all the life / depth out of my system, I was convinced that it was a waste of money.

I ended up reworking how my components were connected (towers via XLR and sub via front pre outs rather than the sub out) as well as spending a ton of time slowly tweaking the target curve in DIRAC.

Depending on the song / master, in some cases you really don't notice much of any difference with DIRAC, in other cases it is a night and day difference.

DIRAC doesn't reduce any of the detail in playback, but it does kind of blend the sound stage into a more fluid and room filling experience. There is less separation and sterility in the music, the sound stage is more velvety and warm, also the sound feels less like it is coming from distinct speakers and more like it is filling the room. One thing it certainly does is reduce the harshness or brightness that seems to be a common complaint about the unit, which I also struggled with until getting DIRAC sorted out.

Anyway, happy to answer any questions if any come up.

The NAD C658 seems to have everything I would want in a streamer/preamp/DAC and so I requested a demo of one the other day paired with the C268 and played a range of music from Tidal outputting between B&W 606s and 702 s2s for a lower end to high end comparison. Through both sets of speakers the sound was insightful and was able to show off a superb soundstage (especially with the 702s). Despite this, I have an issue. The sound seemed quite thin. I was informed that dirac had not been set up and tone controls were neutral. Is this something I could overcome with dirac correctly set up. I would love to purchase this combo but can't currently audition it from home due to lockdown and couldn't justify purchasing something without first knowing it could provide the sound I'm looking for. Have you experienced or anyone else experienced anything similar?

Thanks.
 
Hi, I've found a very detailed review of this device which discusses the Dirac effect, and it seems that it makes a major difference:


The review also mentions the optional HDMI module, which converts the device into a stereo AVR (3 HDMI channels and ARC).

The reviewer did his review with Elac active speakers, which was perfect for me as I'm looking for a preamp streamer & headphone device to use with my Dynaudio actives.

The NAD certainly looks brilliant. The only downside (which is not NAD's fault) is that it uses BlueOS which uses Tunein as the built-in radio streaming app. As many will know, this is now crippled and presumably will soon go out of business. Has anyone found a different radio streaming app that can be used with the NAD as a built-in solution?

As it's a Roon endpoint, perhaps that will offer a solution? I realise that you can stream from a phone radio app to the NAD on bluetooth, but that's just a workaround.
 
The only downside (which is not NAD's fault) is that it uses BlueOS which uses Tunein as the built-in radio streaming app. As many will know, this is now crippled and presumably will soon go out of business.
TuneIn works fine in BluOS. What makes you think otherwise?
 
TuneIn works fine in BluOS. What makes you think otherwise?
You've completely missed my point. Tunein is now crippled. It doesn't provide access to foreign stations any more. Google it.
 
It doesn't provide access to foreign stations any more. Google it.
Don't believe what you read - I've just been listening to a couple of US stations this very evening. What's more you can access any station by storing it's URL as a TuneIn favourite in BluOS.
 
I don't have to believe what I read. I have the Tunein issue with my Marantz amp. It's not platform dependent. I can see for myself that most foreign stations have disappeared, apart from a few which are mainly news. Tunein has a copyright issue and most foreign channels are blocked. Copying and storing a URL manually is not a solution.

I don't know what your issue is but you've clearly decided to have a fight for no reason at all. Go away.
 

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