NAD C390DD Direct Digital DAC/Amplifier

[Sam Lord]

I guess I had heard that in general, Sabre based DACs were more edgy and bright. My Nova fits this description, and although I can tame that with the tube buffer, the soundstage shrinks when I use it. I was looking at the AKM based Schiit Gungnir and the NAD M51 or C390DD. I heard the C390DD two days ago and it was nice and smooth, but still dynamic.

I see. Well you're trusting your ears, that's the crucial thing. It might be true that the Sabre chips demand more of the supporting circuitry...but I think there are too many good-sounding DACs using it to ascribe a general character. Personally I'd love to hear the Invicta, but I'm over budget already! If I hadn't already had 4 fine Bel Canto amp channels and their preamp, I would surely have looked hard at the new NADs. Or more likely would have built some Hypex nCore amps... Cheers

[Paul R]

Actually - every single Sabre DAC I have heard has had a sound about it I identify as unique to Sabre DACs. Yeah, people tell me I am crazy, but I still hear it. Every AKM based DAC also seems to have a unique and identifiable sound to me. Wolfson's sound all over the map though.

 

I hypothesize that the chip lends itself to a certain kind of implementation, but who knows? I do not, that is for sure. But Sabre DACs all have a certain kind of sound to them that is identifiable. Not that they have to I suppose.

 

Paul

 

I see. Well you're trusting your ears, that's the crucial thing. It might be true that the Sabre chips demand more of the supporting circuitry...but I think there are too many good-sounding DACs using it to ascribe a general character. Personally I'd love to hear the Invicta, but I'm over budget already! If I hadn't already had 4 fine Bel Canto amp channels and their preamp, I would surely have looked hard at the new NADs. Or more likely would have built some Hypex nCore amps... Cheers

[squidly]

So I got a good deal on a demo C390DD and I've been doing a few comparisons for the last 4 hours. ( I wish I knew how many hours were are on it...)

1. NAD C390DD on it's own.

2. NAD as a DAC/pre, running through my Peachtree Nova's amp.

3. Peachtree Nova on it's own.

I ruled out the Nova right away. Snare and bass drums are spot on, but voices and horns are harsh.

Option #2 has more body to the sound than the 390 and is more forward. The Nova definitely benefited from the 390's DAC. The bass and mid-bass have a bit of bloom. The soundstage is wide, but instruments aren't quite as coherent as...

Option #3: Has even a wider and more 3D soundstage and everything is sharply in place. The sound is very smooth and everything is very evenly toned. Nothing draws attention to itself. Brush strokes on jazz track snare drums are well resolved. Piano was very very realistic.

 

Before The C390DD, I had a strong hatred for class D amps. I've tried out a Bel Canto and the new Nova125. Both were way too excited of an amp. With the 390, I found myself more engrossed in my music than I have been. I played around with the EQ a little and I know I can get things sounding better after running the test tones. The other part I need to try with the EQ is the sub crossover. Right now I have a Velodyne SMS-1 flattening out my bass response. I hope the 390 does a good job with that so I can consolidate my equipment. I was hoping to get an idea of what a NAD M51 teamed with a class A/B amp might sound like, unfortunately the Nova isn't the greatest amp to test with. Anyway, so far, so good. I can see why the C390DD has been getting good reviews. There's a good chance I'm keeping it.

 

P.S. Sorry, that last paragraph was scatter-brained.

[wgscott]

it's the first paragraph i am struggling to understand. Are 1 and 3 switched?

[squidly]

Agh. Yes, 1 and 3 should be switched.

[wisnon]

Oh, OK

Makes sense now.

[Bromo33333]

 

Before The C390DD, I had a strong hatred for class D amps. I've tried out a Bel Canto and the new Nova125. Both were way too excited of an amp. With the 390, I found myself more engrossed in my music than I have been. I played around with the EQ a little and I know I can get things sounding better after running the test tones. The other part I need to try with the EQ is the sub crossover. Right now I have a Velodyne SMS-1 flattening out my bass response. I hope the 390 does a good job with that so I can consolidate my equipment. I was hoping to get an idea of what a NAD M51 teamed with a class A/B amp might sound like, unfortunately the Nova isn't the greatest amp to test with. Anyway, so far, so good. I can see why the C390DD has been getting good reviews. There's a good chance I'm keeping it.

 

 

I don't think you will do wrong with it - but if you are going to use your Nova as the amp, save yourself a $600-$1000 and get the NAD M51.

 

I was going down the route with the 390DD, and then paired up a M51 and a Parasound Halo A23 and it was significantly better for about the same money give or take.

 

For me, the strength of the 390DD is in the "all in one" aspect of the package. If you are contemplating using it as a preamp - then save the cash and get hte M51. I think the M51 is a better DAC overall than the 390DD also since you can pair it with whatever amp you want - or even use it to drive self powered speakers.

 

I have never found the room EQ feature to be "worth it" from a compromise point of view. My solution was to get two smaller subs and position them in the room to get a nice smooth bass response.

[squidly]

If I went with the M51, I'd sell the Nova and have to buy another amp, and then I'd have to keep the SMS-1. so it would cost me more by not selling those 2 things.

I really do like the all-in-one aspect (I have a rats nest of wires right now) and the C390DD's amp WAS the most agreeable to me.

I'm still going to log more listening hours before I decide, but it looks favorable to the 390.

[Bromo33333]

If I went with the M51, I'd sell the Nova and have to buy another amp, and then I'd have to keep the SMS-1. so it would cost me more by not selling those 2 things.

I really do like the all-in-one aspect (I have a rats nest of wires right now) and the C390DD's amp WAS the most agreeable to me.

I'm still going to log more listening hours before I decide, but it looks favorable to the 390.

 

I could have gone either way - the 390DD is a good amp by any stretch. But I had thought you were thinking of using it just as a preamp (I didn't know you could ... I didn't consider it). My application forced my hands a bit - but I am very happy with my destination. I suspect I'd have been fine with the 390DD, too. The amount of cabling bothered me, too - but 1 set between preamp and amp - and a few digital inputs meant either path was cleaner than what I had already!

 

I don't think you have a wrong choice in there!!

[wgscott]

At least part of the attraction of the 390DD is that the DAC is the amp, so using it as a pre-amp sort of defeats one of its primary purposes. My guess (and it is only that) is used as a pre-amp, the signal either is re-attenuated, or somehow the gain is much less, and then an extra component gets added into the signal path chain.

[Bromo33333]

WGscott - you are correct!

[squidly]

So far using the NAD's subwoofer crossover and EQ has been disappointing.

I'll try full range tomorrow and dial it in with the subwoofer's own controls.

I'm using pink noise and an FFT analyzer to smooth out the peaks and dips (can't get rid of a 110 Hz dip), and on the screen it looks about as good as with the Velodyne, but my ears say otherwise.

[wgscott]

It is hard to get rid of dips, because they are due to destructive interference. You can't amplify a signal that is cancelled out.

[squidly]

After all this, I've decided...to go to headphones. About 2 weeks before I bought the C390DD, I dug out my Sennheiser HD590's and started listening to those more than my hi-fi system. The C390DD is very, very good sounding, but I would rarely finish a song before skipping to another. With my headphones, I would listen to an album that isn't in my top 25 favorites almost in it's entirety. I just love the intimate sound and also being able to lay down on the couch and relax. I'm still glad I went down this route though, because I certainly leaned a lot.

[wgscott]

Does that mean you sent it back?

[squidly]

I'll be sending it back on Monday.

[wgscott]

Good catch - the high level outputs won't work well - looks like there is a Subwoofer output on the back (RCA) that might be the best option. Also appears to be a cable with all kinds of things in the path the stabilize the load as well as having a better ground reference.

 

I've borrowed a NAD C390DD and can verify that Rel high-level hookup works fine when done this way (only way I tried): Red to R(+), Yellow to L(+), black to ground terminal located next to the power cable input. It works better than with my current amp, i.e., dead silent (when it is supposed to be). With the NAD hooked up and powering my speakers, there is absolute silence when the music is not playing. I mean not a molecule of air is displaced. Dead, absolute silence. It sounds good when it plays music, too.

[trappy]

Have any you folks listened to much classical vocal music or opera on the NAD? It's the one area I have serious reservations about -- I find male vocals especially quite chesty, shouty, and lacking in foundation. I continue to also find it a bit frustrating at what I'd call medium levels. Very low it keeps focus quite nicely and at high levels it rocks out excellent well -- as long we're not dealing with the aforementioned vocals. But at medium level it feels like (and I apologize, this is ridiculously subjective) it seems like that amp has trouble figuring which frequencies are important. I often have a hard time figuring out where to put my attention. I would say this has improved over the past two months (which may be psychological) but I still find it vexing.

[PeterV]

Hi Billy and Julf.. ;-)

 

Long time since I visited this thread, but I want to share with you and other readers my 'Succes of the Month' with the 390DD

 

Finally I had time this weekend for an experiment with upsampling a 16/44 WAV file to a 32/192 upsampled version. To my astonishment, I achieved immediate (and extremely audible) success with this 32/192 rip method with Diana Krall's CD ' Love Scenes’

 

This 'off-the-fly' 32/192 audio experiment clearly revealed to me the following:

 

- The size of Diana Krall's voice, the air around it, placement, size and depth.., a clear and huge increase in all dimensions

 

- The dynamics of the contrabass and the piano does improve as well

 

- Pace, rhythm, tonal balance.., yes again a huge improvement!

 

- Articulation, oh boy.., what ease and presence. Large improvement with S- T-, F- pronunciation and higher frequencies

 

- I also experience a drop in the noise level..., less hiss, even of the hiss which is present in the original recording.. Maybe this decrease is caused by the intense increase of micro- and macro- dynamics. Since our human ears are very sensitive to human voices, you will require less volume if the sound level of the voice increases.. This effect is extremely present during the song ' I don't stand a ghost of a chance with you ' During the production of this song, it can be heard that Diana's voice is recorded with a separate audio chain, which introduces some analog tape hiss. The recording of her voice clearly has more noise than the subtle contrabass recording. When playing the original CD in a CD player, this high frequency hiss will be easily heard and seems to be 'fluttering' somewhere around the critical domain of the DAC of my CD player and or tweeters and is for a fraction of a second over-present and unpleasant to listen to. Playing the same song in 16/44 WAV file from mini laptop is already much more pleasant.., less hiss, less jittery analog tape noise sound. But with the 32/192 upsampled version the hiss is almost gone!

 

From this experiment I get the impression that with this increase in bit-depth and sample rate, the DAC of the NAD C-390DD has much more ease to reconstruct the final analog sine wave and has more 'grip' on this high frequency hiss, which is therefore reduced to a still audible, but at a much more pleasant, more silent noise floor.

 

The overall sound of the recording has become much more ANALOG and smacked me in the face.., as if I have been listening to an HDtracks version of the original CD..! This ‘of-the-fly’ upsampling method is in my setup a true audiophile upgrade. Be aware that this will probably only be valid if the 32/192 WAV datafile is being streamed ‘off-the-fly’, preferably direct from an USB stick or SSD.

 

I have now become utterly convinced that the 35 bit/108 MHz architecture of the Zetex ( now CSR owned DDFA®: CSRA6000 ) DDFA chipset of the NAD C-390DD has much more headroom and much more hidden qualities than the market and the NAD electronics engineers or their marketeers know or are willing to tell us (sorry NAD, I have asked too many times to disclose this, as well as request for future DSD and DXD capabilities of your beautiful DAC-amplifier)

 

The learning curve I am going through ever since I own the NAD C-390DD has been (and still is..) a very interesting and exciting one! It feels like a step-by-step discovery and search for audiophile bliss..

 

First I had to discover which input sounded best, and I ended up with AES/EBU. But it was not possible to play 24/192 HDtracks direct via USB using my mini laptop. This was solved with the USD-01 USB-S/PDIF converter, which was the first step towards High-Res 'nirvana'. But USB-B in or S/PDIF in does not sound as warm and pristine as the AES/EBU input was my personal experience... Luckily enough, this problem was solved with the Canare S/PDIF - AES/EBU converter, since this trick seemed to work well within a NAD M2 chain. And indeed it worked out well on mu C-390DD as well.

 

Several months ago I read the review of the WiFi IUSB power supply and purchased it. Since I am still playing my music collection via a cheap HP minibook, it seemed a logical and very affordable step to try this solution. The IUSB power supply unit separates the audio signal completely from the power signal. Beside a galvanic isolation, more improvements are being done in this small unit and (luckily) the improvement was immediately present and audible.

 

As you will understand, all above 'best sounding' solutions which Iglued together, are both on paper and in practice not a very neat one. It therefore still annoys me that I have to work around many issues in order to be able to achieve better sonic performance in my current audio chain.

 

So my interest for an even better solution still exists and I am convinced the solution for this will be the shortest signal path which can be achieved between a computer and the DDFA chip of the NAD-C390DD ( and its family breed..)

 

So if NAD electronics will not be convinced that there is an audiophile 'need' for a new module which will enable I2S-I2S connectibility between an audio PC and the NAD-C390 DD, I will proceed and arrange a modification to be made by an audio electronics expert.

 

So there are still many adventures left with my quest through this new digital forest searching for the holy grail for my musical 'Kindergarten'

 

So the future looks and sounds bright!

 

- Peter -

[wgscott]

Hi Billy

 

Yo.

 

Large improvement with S- T-, F- pronunciation

 

What about the U- ?

 

 

 

 

 

 

 

But, seriously, folks ... thanks for posting your observations. I'll give it a whirl. I've been avoiding upsampling while listening thus far.

[PeterV]

Haha wgscot ;-)

 

I understand your reluctance and skepticism quite well.. I am also not looking much forward in upsampling each and every WAV file I have on my server.. But it was such a pleasant surprise to notice a large difference, that I wanted to share this with the forum..

 

I tested how DBpoweramp is handling a 'batch' conversion and upsampling of some of my flac files as well as wav files and even upsampled a 24/192 HDtracks flac to 32/192 WAV and all tests were convincing enough for me..!

 

I will probably upsample just some of my top 10 maybe top 100 albums for 'special listening' occasions

 

It might be a start of a new debate that BITDEPTH (32 vs. 24) has op potentially larger influence on sound quality that sampling frequency ( 44 - 96 - 192 or higher)

 

It might sound stupid to do a test with even higher bit depths.. ( 64 / 768 .. just kidding....;-) Bet OK guys, we are audiophiles or not..

 

I foresee a large shift of DAC manufacturers going towards a 32 bit or higher archtitecture.. It will keep theirs sales running well and as long as the improvement is audible and digital audio will slowly enter the superior analog sine wave sound, this will be an inevitable path.

 

By the way, interesting paralel developments can be seen with HDTV .. Sony will introduce soon their 4K OLED high definition TV. it encorporates also upsampling algorhythms which enables huge improvement of low-res material as well. Even youtube content will be much more pleasant to the eye.. Interesting!

 

- Peter -

[attunement]

I've been lurking on this site for several months, but this is my first post. I got a NAD C 390DD a few weeks ago and thought I'd share my results.

 

First thing I noticed was how extremely transparent and detailed it was. But after listening for a couple of weeks, I became increasingly aware of a number of somewhat disturbing artifacts. On some tracks both my girlfriend and I could detect a subtle, rattling distortion that was hard to identify. Was it a part of the music, or were we hearing a physical defect rattling in the speaker (KEF LS50s)? Female singers could sound wincingly harsh when belting out a high note. And music tracks with a lot of layering of instruments seemed to lose focus, causing the sounds to start to mush together.

 

Granted, these things were subtle and not a deal breaker, but significant enough to deter me from thinking that I had found my dream system in the NAD C 390DD. I read on this site and other places that a USB/SPDIF processor between the computer USB port and the NAD could improve the NAD. I, like many, was skeptical on this, feeling that NAD surely would have taken care of any USB flaws in the asychronous USB connection, at least in the audible range.

 

Despite my skepticism, I ordered the Audiophilleo 2 with the pure power option, just to see for myself. While waiting for it to arrive, I went through my music library to find a number of tracks that I and my girl friend thought had troubling/unpleasant artifacts that I'd test the Audiophilleo on.

 

After the unit arrived and I plugged it in, I called up the 1st track of Nick Cave and the Bad Seeds new CD Push the Sky Away. In the first track there was a muffled kind of distortion that I couldn't tell if it was coming from the synthesized keyboard instrument or from something rattling in a damaged speaker. But with the Audiophilleo, an increased sonic clarity was brought to the track that made it obvious that the distortion was in fact an intentional processed artifact in the sonic material. The distortion was clearly an intentional part of the sound.

 

Being able to hear sound files on this level of pinpoint clarity was an amazing experience for both my girlfriend and me.

 

I then brought up the first track of Patty Griffin's new album American Kid. There, in the chorus, she really belts out a high note that without the audiophilleo became more shrill than musical. But with the audiophilleo the high note stayed sweet and musical, even though the volume had increased.

 

I became so excited that I began going through all my files that might have something a little unpleasant about it, or where the elements in the music got so layered and dense that the sounds began to blend together and lose their individual space. To both my girlfriend's and my amazement, I couldn't find anything that sounded shrill. The audiophilleo just seemed to take all that digital nastiness away. And no matter how complex the music became, in terms of sound components, we could always pinpoint and clearly identify what was going on, whether it was a brush in the background on a snare drum or a violinist stroking out a couple of notes.

 

My girlfriend, who is no audiophile but is a music lover, began waxing like a reviewer in full bloom, saying things like, "The music seems to be rising out of this deep black silence," and "the detail and character of the music is just amazing. It's like you can hear every single little part."

 

Another benefit that I noticed is that the sonic quality of all musical instruments became subtly, but significantly, more realistic. For example, I have some albums of jazz pianist Bill Evans. I am a pianist myself so I know what the piano should sound like. On my NAD without the audiophilleo, the piano on those albums always sounded a little thin, tinny, and not quite real, which always kind of disappointed me. With the audiophilleo, the realism was delightfully enhanced. Male and female voices were similarly enhanced. I could really go on and on giving examples where the audiophilleo added subtle but oh so important improvements to my listening music.

 

I am beginning to think that the weak link in my computer system ended up being the USB port itself, which was adding just enough jitter and distortion to get accentuated by the NAD C 390DD processing and transmitted by the highly detailed KEF LS50 speakers. Adding the USB/SPDIF processor removed that weak link and allowed the other components to enter into audio nirvana.

[firedog]

On other forums several owners of the unit have reported that the weak link of the C390dd is the quality of the USB input and that sound is taken to another level when using a quality USB>SPDIF converter; so I believe the problem is not your PC per se, but the USB implementation on the amp. This is not uncommon, even with "audiophile" level equipment. Part of the reason there is a thriving market for devices like the Audiophilleo.

[wgscott]

When using the USB connection, how are you controlling the volume? What is the software volume setting?

 

(I'm wondering if the NAD is getting an attenuated, re-mixed signal when operated with USB, and the USB/SPDIF converter essentially prevents you from doing this, and forces you to control the volume completely from the NAD amp itself?)

[wgb113]

So I'm sat here with a pair of KEF LS50s that I feel need some help on the bottom. I'm unable to integrate a sub into my current system unless I go the route of speaker-level connections and I kind of feel like that would degrade the sound quality to the KEFs rather than feeding them right from the amp.

 

I just got my Benchmark DAC2 HGC last week and thought I'd be able to utilize it's unbalanced outputs to the sub's Line IN but their output signal is too much lower compared to the balanced out to my power amp.

 

Now I'm wondering if I should return the Benchmark, sell the Parasound and just settle in with the 390DD. I connect my iMac via optical/toslink and my only other source is a turntable. I like the fact that the Benchmark never converts the TT's signal to digital but the lack of bass is becoming a bigger and bigger frustration for me.

 

attunement,

 

Are you using a sub with your KEF/NAD combo?

 

Bill