Hi-rez DAC - Esoteric K-01 vs. Marantz NA8005

For those who have read my review of the Marantz NA8005 Network Player, and are wondering about the quality of its internal DAC, here is what I have observed after sufficient burn-in of the 8005.

For this A/B comparison, my set-up is as follows :-

A. USB flash drive -> Marantz front panel usb port -> Marantz internal dac -> single-ended analog outputs via Audioquest Lapis interconnects -> Rowland Capri S2 preamp -> Bryston 28B SST2 monoblocks -> VA The Musik speakers

B. USB flash drive -> Marantz front panel usb port -> single-ended Coaxial output via Oyaide 75 ohm BNC digital cable with BNC adapter -> Coaxial input of K-01 -> Balanced analog outputs via Kimber Select IA's -> same Preamp and power amp as above

For redbook format, the K-01 transport is way ahead.
So, I am doing this A/B for hi-rez only.

As good as the Esoteric K-01 is for hi-rez, playing the same files through the Marantz's internal dac is one big step up in SQ, wrt every sonic parameter. Moreover, the Marantz brings a pleasing light touch of warmth to the party.

I can only surmise that this result can be attributed to :-

1. More jitter via the coaxial interface between the Marantz and the K-01
2. Hi-rez is more sensitive to the additional jitter
3. The shorter signal path for the Marantz's internal dac
4. Very good analog ouput implementation of the Marantz even as they are only single-ended
5. Higher quality analog IA's from the Marantz to the preamp
compared to the Oyaide digital cable(the BNC adapters may add more jitter)
6. Higher quality hi-rez dac chips or more advanced implementation and design for hi-rez in the newer Marantz compared to the older K-01.

I will continue to use the K-01 for the several hundreds of CD's and some SACD's in my collection, but will use the Marantz direct for hi-rez files loaded into the usb flash drive.

Truth be told, I am rather surprised, albeit pleasantly, by the quality of the Marantz's internal hi-rez dac in a product that costs little more than 1k.

Happy listening.
Why not use a computer's USB to connect to the K01. It should sound better if you have a reasonably designed PC. Use SSD, use a linear PSU or fanless ATX PSU.

Thanks for your suggestion. I have tried the usb input of the K-01 from my pc as reported in other threads and the order of SQ for the various set-ups is as follows(increasing order of merit) :-

1. Laptop -> Usb input of K-01
2. Laptop -> Usb-to-coax converter(iFi iLink)
-> coaxial input of K-01
3. Usb flash drive -> Marantz player as in A. above
4. Usb flash drive -> Marantz player as in B. above

Given the sonic results of set-up 4, I will stay with this as I am not prepared to spend more for a dedicated pc(Windows or Mac) music server.

This set-up for hi-rez is leagues better than anything I have ever heard from my current system. Amazing but true.
Apologies for the typo.
I meant set-up B to be at 2nd rank with set-up A to be at the top rank.
Hi Jon, thank you for your very detailed findings. It will be interesting to discover if the new K-01X improves over the original K-01 for high resolution files.... May someone will experience the new device during the next several months.

Yes, it is most likely that the K-01x would have upgraded hardware chips for hi-rez. Unfortunately a software upgrade alone for the K-01 may not improve the SQ for hi-rez.
This is unlike the PS Audio Directstream which has FPGA implemented and thus significant upgrades can be achieved by software alone for several years down the road.
Some day, all dac's should be made this way - FPGA upgradability in an instant. :)
DirectStream 1.2.1 is a huge step up in SQ.

Unfortunately, the K-01s use off the shelf AKM DACs so it's unlikely to get such a big jump. That said, the K-01/03s do use a DSP chip to resample/process the signals before feeding the AKM DACs and I think there could potentially be improvements from a firmware update on the DSP.
Thanks so much for following up with your Marantz DAC impressions.
I think that feeding the Esoteric from the Marantz puts the Esoteric at a significant disadvantage.
This goes to show everyone, I have said many times, It is not what the componet cost,or hailed as best available when comes to digital, I have had a few members laugh at the idea that a player I have bought for the second time has out performed my last former player that cost nearly 3 times more money, I am very suprised that jon2020 has not been attacked by brain washed disturbed audiophiles who try to justify that their $20,000.00 unit is the best, and insult him to the point of unbearable conversation!, like I have been recently when I mentioned how good the unit sounds that I have now compaired to the unit I had before, Jon2020, I say you are Bold to post this, it appears at the moment, you are lucky this far, good luck, and thankyou for bringing this compairison out, cheers.
Tomcy6, AL,
Thanks for your kind words. In this hobby, we need to tell it as it is. Failing that, we will be caught out one day.

For now, I shall try to duck any "metralla", as Sabai would say in Spain, that comes my way. :)
Thanks for your kind words.

With regard to your comment about the Esoteric being disadvantaged by the Marantz, it is true with the redbook format.
But with hi-rez files, the Marantz does better than the Esoteric. This outcome, of course, should be taken only in the context of the 2 set-ups described and the reasons for this could be any or a combination of any of those listed above.
Since I don't know in which threads you were attacked, I will not go into that conversation.
But it could be very well that people do not see a "system pic" for you, whereas they are clearly able to see that Jon202 has a system page and that he has the "real" experience. I am not saying that your experience is not real, but having to "show" some experience is much different than just "saying" about your experience.
I would never attack a person, whether he has a system to show or not, since everyone has a different experience. I personally prefer not to respond to system pages that do not have pics. Sorry - but that is my take. It happened after a person on whose page (without pic) I responded replied back saying that - oh, that would be something I would love to get. So why the hell did you put that in your system page and not indicate that you do not own it!!

So maybe if you have a system page, you "could" have been well received. Just saying.
I agree that more $ does not mean better sound especially in the realm of chips and digits. If digital players progress as computers have, they should become cheaper as they get better.

Jon 2020, have you compared playing an SACD in each player?
The Marantz does not have a disc spinner for CD/SACD. But comparing an SACD played through the K-01 with analog out to hi-rez played from a usb flash drive through the Marantz's internal dac, the SQ comes very close. It all boils down to the quality of the recording in each format. As we all know, some hi-rez recordings are of questionable origin or mastering and so too are some SACD's.
Sorry about that, I was thinking SA8005 instead of NA8005.

You hit on a good point, the quality of recordings. I think that we could get major improvements in sound quality out of our systems if record labels would make it a priority. Maybe they will as the high-res download market matures, we'll see.
This is a rather belated update but as always, better late than never.

After at least 200 hundred hours of burn-in for the Marantz hi-res dac, it trumps that of the K-01's in every way. The K-01's internal dac sadly has indeed seen better times.
My current set-up is as follows :-
1. Redbook CD's spinning in K-01 as transport alone > Marantz dac > preamp
2. Hi-res pcm/dsd files in usb memory stick > Marantz dac > preamp

I am in audio heaven.

Cheers! J.
Great news Jon2020. Now if they would lower the prices on downloads, we'd all be in audio heaven!
I feel the same way, Tomcy6. Those hi-res prices are still hard to swallow; I only download favorite tracks, not whole albums. Linn Records and a few other download sites allow this while HD Tracks doesn't.

It's really unfortunate that you are not finding your k01 usable as a Dac.

I have not compared the NA8005, presumable the NA11 would be very nice.

The K-01 trashed the Marantz Sa11s2 by a fair margin and never looked back.

I like the Marantz product. very good value, construction and sound. It was beautiful sounding which did everything very well, but was not as open refined and detailed in the highs and lows. It doesnt have the grip of the K-01.

You should try a really good digital cable, it's a waste not using it in you setup.
The K-01 for Redbook cd as a standalone player is very good but when used as a transport driving the Marantz dac, cd reproduction is at a different level altogether. A better digital cable will make the combo sound even better but sadly won't make the dac of the K-01 better than that of the Marantz. I guess the oft-quoted adage that the transport is more important than the dac holds true here. The K-01 with its VRDS Neo drive remains a very formidable transport for any high-end dac. That it can make the "lowly" Marantz sound so good for Redbook cd is revelatory.
I have been wondering how the K-01 can sound better following your suggestion to upgrade my digital cable.
Just yesterday, I had a "lightbulb" moment and downloaded the usb driver. I had done this before some time back but wasn't impressed and forgot all about it. But with the new K-01X and upgradeability by software and hardware for the good old K-01, I was hoping that the latest driver may "do" something.
Well, I couldn't be more surprised. The latest usb driver was ear-popping in a very positive way, to say the least. The sound of hi-res material wis now vastly improved. It's like having a totally new dac.
I can't imagine Esoteric could have upgraded the firmware together with the usb driver but that is what I suspect. There is no other way to explain this. Even cd's and sacd's sound better.
SQ got better when I used the iFi usb-converter to the coax input and even better still with the Gemini dual-headed usb cable and iPower to separate the audio signal from the dirty pc usb power. SQ went up a notch again with the iPower plugged into the Shunyata Triton and another notch when I played hi-res files from a thumbdrive rather than from the pc hard disc drive. And so, here I am at the next level of audio heaven.
Needless to say, the Marantz is now relegated to player/headphone amp duties in the bedroom.
To all K-01 owners thinking of selling theirs, hold on tight to these babies until you have downloaded the latest usb driver. With this, the 'new' dac section is not only very good but shockingly good.
Cheers! J.
Hi John, your report is fascinating. After drivers update, have you tried to feed K-01 directly to your amp? ... Results? G.
Will try out your suggestion and revert.
I remember someone posting here that data retrieved from the K-01's transport goes through a dsp engine first before the D-A conversion. As dsp is software-driven, this would explain the change in SQ. No matter how it is done, it has been a truly magical transformation. :)
I have tried direct to amps but SQ was taken a few notches down compared to via preamp. I can think of 2 reasons for this :-
1. The output impedance of the K-01 does not synergise well with the input impedance of the Bryston monos as have been in the past
2. Digital attenuation for hi-res 24-bit material is not as forgiving as with 16-bit redbook. That said, redbook still sounds better without digital attenuation.

As regards my suspicion of a firmware upgrade being incorporated in the usb driver download, this is strengthened by a change of one particular aspect - where it used to be that if the K-01 was not locked onto a signal for any input other than CD/SACD, the chosen input options for Coax/Opt/Usb would blink forever until a signal is received. But now, after the driver download, for any chosen input without yet a signal lock, there is nary a blink.
Cheers! J.
Hi Jon, very interesting...

* What is the balanced output impedance of K-01... And what is the input impedance of your Bryston?

* what parameters of K-01 direct to amp fall short, vs it going through your linestage?

It is also entirely possible that Esoteric has implemented DAC volume attenuation as an afterthought -- to be used only in a pinch -- rather than the direct connection to amp being core/primary functionality.

Thanks, Guido
The output imp for the K-01 is 100 ohms balanced while the input imp of the Bryston monos is 15 kOhm - not a good match.

How is SQ better via preamp? Let me count the ways :-
1. More body/tone/color to instruments
2. More air and space around instruments
3. Bigger soundstage, more depth with a heightened consciousness of the dimensions of the recording venue
4. Sam Tellig - more "there there"
5. Harry Pearson - more "continuousness"
6. Robert Harley - a "stunning achievement"
7. John Atkinson - it would be "churlish to nitpick"
:) :) :)
Cheers! J.
Hi Jon, I agree, impedance match is not the best.

The way you describe K-01 directly on amp is exactly how I had experienced it on my system in olden days... Good in a pinch, while one waits for the cavalry to come to the rescue *grins*

I am thinking that the major problem might not be one of impedance mismatch, but a lack of focus/attention on the design of the attenuation subsystem... More than likely a deliberate marketing decision, as so many DAC manufacturers are doing a superb job with direct-to-amp connection, at redbook resolution and above.

But... Never say never again... We still might see the day when Esoteric Dac volume control rises to the proverbial occasion... Here's to Hope!

Hi Jon,

What network player are you using now in place of the marantz ?
You find that the new drivers with usb superior to coax.
I have never really used the network feature of the Marantz as I do not want to run a 30m ethernet cable to my router. So the Marantz is now used only as a dsd decoder.
Yes, even with the new usb driver, the coax input still sounds better than the usb input. I guess this has to do with the original usb hardware. I can still send it off for an upgrade to the new usb board. But that would mean shipping it to Japan and no music for a few months.
The interesting thing about this driver download and incorporated firmware is that it makes the K-01 sound like a different dac. As stated elsewhere, data from the transport goes through dsp first before final d-a conversion. Does this make it similar to FPGA? Can't say for sure.

Well, the sound has indeed changed. If I maintained the same settings as before, ie ORG upsampling and OFF filter, things are tilted slightly to the warmish side with a mild blunting of transients. But transients perk up again with SLDY1 for filter. SLDY2 sounds a bit too sharp for my system. So, I have settled on ORG/SLDY1 for now. I still prefer no Upsampling to 2x/4x.

There are 2 striking changes to the sound. Firstly, there is a vast increase in the soundstage in all dimensions with precise imaging and placement of instruments on the stage. You are more aware of the acoustic environment esp with orchestral works. It makes one curious as to where the orchestra is playing.
Secondly, instrument body is now more fleshed out and there is more weight and bass foundation to orchestral works. Classical pieces on redbook, sacd and hi-res all become more there there.
Cheers! J.
I am confused here after reading your threads. Did you upgrade your K-01 to full K-01X specifications at the factory or did you just download the new K-01X driver that is getting you better results?

Sorry man....I know the confusion is mine.

I have not upgraded the K-01 to full K-01X, just downloaded the latest version of the usb driver for the K-01. This has improved SQ for all formats - cd, sacd and hi-res, which seems like a firmware upgrade to its internal dsp engine.
As I rediscover more and more of my cd collection, I switch filters between OFF/SLDY1 and upsampling between ORG/DSD depending on the recording, and in the context of my system.
For hi-res, it's ORG/OFF every time - not messing with tbe native signal gives the best SQ.

You are very likely right and prescient in a previous post above :-

"......That said, the K-01/03s do use a DSP chip to resample/process the signals before feeding the AKM DACs and I think there could potentially be improvements from a firmware update on the DSP."

Cheers! J.
Thanks Jon,
Seems for Mac users there are no new drivers for the K03, as the original driver (Driver software for Mac "Version 273.4.1") is the only driver available. For Windows OS they have a newer downloadable driver for "X" upgrade....is that your take?

Hi Mark,

From the Esoteric link below, I downloaded the hi-speed usb driver for the K-01, not the K-01X. Officially, the download does not say that it is an upgrade to the K-01X but by the improvement in SQ, it looks like it could be a firmware update as predicted by Doggiehowser.