Hi-Res+Esoteric K-01+USB input+JR Capri S2

With the addition of the Jeff Rowland Capri S2 preamp in my system, I revisited hi-res downloads from my PC to the USB input of the K-01.

My initial impressions of hi-res through the K-01's USB input and digital volume control were disappointing as noted in another thread.

But now with the JR Capri S2 preamp in place, playing hi-res through the K-01's USB input and its balanced analogue outputs, the difference is indeed night and day. Every sonic aspect is improved to another level by leaps and bounds.

The only logical explanation for this is that hi-res needs to be played through an analog preamp to maximize the potential of its resolution. When playing through the K-01's digital preamp, the loss of bits at less than maximum digital volume becomes readily apparent during listening.

Perhaps your findings and mine are system dependent. I also have found the same results after comparing the K-03 connected directly to amp vs MAC Mini to K-03 via USB Input and Balanced Analog out to Rowland SynergyIIi Pre.

The TAS review of the K-03 indicated as much during their review of the product. To my surprise additional refinement was achieved after inserting a USB Converter between computer and K-03 with S/PDIF (BNC Connector) out to K-03. It removed additional glare and improved micro/macro transients.

The K-03's CD playback of HiRez or Redbook CD's still yields the very best SQ when compared to my computer rig, however; have closed the performance gap with the changes made to date.
Hi John, I am not surprised... As much as I loved K-01, its attenuator sounded like a bit of an afterthought when it was demoed to me... While Capri S2 is an adorably sounding pre.

On a related note, what PCs are you using on K-01 and Capri? Shunyata has a new mid-cost Z-tron Alpha that is said to have been optimized for digital devices and devices with an SMPS... Capri S2 uses an SMPS.... And K-01 is a digital device of course.

I use PS Audio AC12 power cords for both the K-01 and the Capri. I may consider the Z-tron PC's when an opportunity for a home audition comes along.

Your observation about better sonics with USB to SPDIF converter is interesting. It is possible that SPDIF is superior to USB direct if the converter is designed well and with premium parts.
I am a bit puzzled when you say that your player's CD playback of hi-res is better than your computer rig. Do you mean SACD?

I am now fully convinced of the benefits of hi-res. When it is well implemented, it can indeed sound better than redbook cd.

Yes, I was referring to SACD's.


What USB to SPDIF converter are you using?
The MF and Bel Canto devices have been well received by the audio press and I hope to audition these at home.

I am using the Bel Canto REFlink. After comparing several USB Cables (Audioquest Diamond, Alethias, Transparent Performance, Silver Starlight ....) I felt the Audioquest Carbon provided the best results. The REFlink comes with a BNC to RCA Adapter.
Hi all,

I need help about 192/24 files played through the same set-up as above. With JRiver, the K-01 accepts the 192/24 signal via USB from my Windows 7 PC by flashing 192 on its display. But once playback begins, I hear continuous pops and crackles amidst the music. When I go back to 96/24 files, the pops and crackles are gone.
Does anyone have the same experience and is there a solution to this?

Many thanks in advance.
Perhaps this may help. Picked this from a forum at Computer Audiophile.

Why you hear Clicks and Pops:
Very grateful to Gordon Rankin to provide valuable information on why sometimes, we hear clicks and pops when using USB DACs. This question crops up regularly in these pages.

See the reason here.

The computer's flow of data to the DAC is not right.

Usual Culprits:

- Adjust the hardware buffer in the player software to a higher value
- Adjust the ASIO4all buffer in the supplied applet, if you use that software
- The computer's CPU is grossly overloaded
- There's another device on the same USB hub as the DAC
- The driver supplied is not working correctly (maybe corrupt)
- (Obscure) The 5V supply in the DAC circuit is not as it seems - contains spikes/crud or drops off
- You're listening to Rap music where this is fairly normal artistic content
- If the music files are on a NAS, especially over Wireless, the data flow can be incorrect

Good Luck!
I have solved the problem myself. Sheer dumb luck! In JRiver, under Options -> Output settings -> choose Wasapi. Viola! No more pops and crackles; just sweet, sweet 192/24 music! Enjoy!
Our posts crossed. I did try to increase the buffer with ASIOforAll but that didn't work.
I then remembered reading somewhere that Wasapi is the preferred way to go. So, I switched from ASIO to Wasapi, and that's all, folks!
Glad to hear you found a solution.
For anyone wondering what the differences are between ASIO and WASAPI, here's a link from a Computer Audiophile forum.

Here is another link.

I just discovered something and would like to share it with you and other K-01/K-03 owners out there.
Apparently the K-01 has a built-in USB to SPDIF converter. If you go to the Digital Out menu and choose THRU, the player cnverts the usb signal to spdif before routing it to the DAC.
I tried it and find the sonics way better than before. Since you have the Bel Canto Ref link, you can compare with and without it in the chain.
On a related note, playing music from an ultra fast SD card in the SD slot sounds better than from the computer's own hard disk or from a Usb thumbdrive in a usb port.
Also, if you use JRiver, Wasapi - Event style is the best output mode setting.
Happy listening!
Seems I set the Digital Out to ON when I originally landed on the preferred settings. I performed an A/B comparison again after reading your post and adjusting the Digital Out to THRU. I currently use Amarra for playback.

I chose two high quality/dynamic recordings (Redbook CD's) for the listening session. Emmet Cohen "In the Element" - Track #7 and Juan Manuel Certo "The Puerto Padre" - Track #3.

Tracks were loaded into Amarra Playlist w/Cache on. Then closed iTunes.

Scenario #1 - MacMini Music Server > K-03 USB Input (Using Audioquest Carbon USB)
Scenario #2 -MacMini Music Server > BelCanto REFLink (Using Audioquest Carbon USB) > K-03 Digital Input (Transparent Reference 75Ohm digital link)

My Findings: The REFLink provided better overall SQ in every facet
- Improvement in overall timbre
- Better attack-decay
- Improvement in micro/macro transients
- Bass was a bit more defined/authoritative with just a tad less bloom
- Sound stage extended out R/L of speakers an add'l 2-3 feet

Equipment used: Jeff Rowland M312, JR SynergyIIi Pre, & Avalon Indra's.

I was hoping for the settings change to result in a sale of the BelCanto; Dang! looks like it is staying put for now. Thanks for the heads up though Jon.


I was hoping to hear that the Ref link was blown away by the player's digital throughput but ..... Dang! Looks like I will be now forking out dough for the Ref link. Thanks to you for the heads up, Mark! :)
Cheers! Jon.
I use a Berkeley USB converter to a K03 and found similar improvements.

Hi sfstereo,
Thanks for your input.
Tell us more about your set-up :
Mac or Windows, software, usb cables, etc.
Hi Jon,

My system is a combined HT and 2 channel:
DACs- Berkeley Alpha DAC 2 with USB converter.
Also an Audio Research DAC8
CD players with DAC- ESOTERIC K0-3 and ARC CD9.

Preamp - ARC REF5SE
HT processor - Krell S1200

Amps - ARC REF 250 and Krell Evolution 430E, S275
Speakers - Revel Salon 2
Cables- AQ WEL, Wild Blue Yonder, Diamond USB.
Shunyata Triton with ZiTron Anaconda and Python cords.

Computer is Apple Mac Mini with Pure Music.
USB Converters are abundant now days. The Berkley converter that sfstereo is using is also highly regarded. I have attached a link to a forum at Computeraudiophile.com that includes a detailed review of 15 USB Converters. Unfortunately, the BelCanto USB Converters were introduced after this individuals review. Would love to have a chance to trial the Berkley unit at some point as well.

My advice is to find a local BelCanto dealer and request a unit for a 15 day trial before purchasing as did. I can safely conclude with the research I have conducted that they are certainly system dependent like most gear in the audio chain....clearly the Bel Canto is not the only quality player here in the USB market.


Hope this helps,

You guys have to try this. I initially played all my hi-res files with ORG upsampling and no filter on. While sticking to no filter on so as not to limit the higher frequencies, I switched upsampling to DSD. It was a jaw-dropping experience for me and I hope it us for you too. I tried this with 24/44.1, 24/96, 24/192 files and the improvement was across the board for all sonic parameters. It is as if Esotetic made the DSD upsampling option solely for computer audio.
Happy listening!

Thanks for the heads up, Mark.

sfstereo, I am sure you are a happy camper with your Berkeley unit which had the highest score in the review.

Was curious as to your impressions/critique of your ARC CD9 vs K-03.

I have never owned AudioResearch gear, but; always admired the sound of their CD/SACD players I have heard at local dealers.