HOLO Audio Spring DAC - R2R DSD512

[Superdad]

Well I jumped on the bandwagon and just purchased the Holo Level 3 dac. Unfortunately delivery wont be until late Jan or Feb. Merry xmas to me!

 

Cool tboooe! My new Level 3 has been warming up for a week in my system. Planning to put ears on it for the first time this weekend.

 

 

Sent from my iPad using Computer Audiophile

[Superdad]

Happy New Year Alex! Any initial impressions on your Holo Level 3 DAC yet? I ordered one just a few weeks ago and just got word from Tim that it was shipped out - about a full month EARLIER than Tim estimated! Awesome service!

 

Anyway... looking forward to hearing your impressions of your DAC.

 

Hi Gary! Great to see you here again. Yes, Tim has been terrific and I think he will go far with his good service.

 

Automotive repairs and other house chores took over my weekend--along with a ping-pong tournament with our kids--so I never managed to get an ear on the Spring DAC just yet. This week for sure.

 

All the best,

--Alex C.

[Superdad]

Note: Jesus and company are trying at their end. I just now got off a teamview with Jesus where we tried some alpha stuff to address this issue. There is still work to do.

 

Well I think they fixed the issue yesterday by breaking the ability to run direct, non-DoP DSD with the Holo Spring!

 

[To others reading this, this is sarcasm related to my posts today in the review thread.]

 

So Ted, did you ask Jesus about my issue and if the latest OrbiterOS update could be what is keeping me from doing direct SDM with mR/NAA just to the Spring (works fine with both my other DSD-capable DACs)?

 

Standing by. Thanks.

 

--Alex C.

[Superdad]

Of course Barrow and Scan are both correct!

I own a Holo Spring Level 3, and while I enjoy it, it is true that the clocks in it are very poor compared with the Crystek 575s in the SU-1.  

I am supposed to be receiving an SU-1 soon--specifically so I can use the I2S input.  With a short HDMI cable, hopefully the good Crysteks (as remote master) will still sound better than what is in the Spring.  Of course it is not exclusively about clocking (though it is tempting to consider putting really great clocks on the Spring's board; I've been thinking about getting a hot air rework station for a while anyway...)

 

[Superdad]

1 hour ago, tne said:

Alex,

When you refer to the clocks in the Holo as "very poor", what is this opinion based on? 

I am running mine primarily with AES input from a Mutec MC3+ USB with PCM/192kHz. It is sounding pretty good this way. 

 

 

 

Hi Thomas,

By no means did I intend to denigrate the Holo Spring!  I bought a full "Level 3" and have been enjoying it.

But the clocks in it are just $0.50 generic Asian items (I looked them up and there was no reference at all to them being low-jitter/low phase-noise pieces), and even Tim at Kitsune indicated that Holo said they put all the effort and money into the rest of the design and that at the Spring's price point (remember it starts at about $1,500) they did not have the budget for nicer clocks.  He also said that the follow-on model, the "May" DAC would have better clocks.

That's all I know.

 

Best,

--Alex C.

[Superdad]

Well I own a Holo Spring Level 3 and can assure you that the ISO REGEN is a terrific addition to it.  But obviously I am biased.  Yet there are a great many other Spring/ISO REGEN owners who will back me up on this...

[Superdad]

2 hours ago, PeteG said:

Will the DSD Cyan have a I2s input. 

 

By definition I2S is PCM.  But it could have a DSD over LVDS (w/HDMI jack) input...

[Superdad]

9 hours ago, GUTB said:

The I2S interface was only useful for bypassing the SRC stage anyway. Since there’s no SRC in the DSD version than USB is fine.

 

7 hours ago, pkane2001 said:

That's not the reason for I2S. It's to allow for external DDC or other I2S sources to connect to Holo with minimum overhead, bypassing other built-in interfaces such as USB, SPDIF, etc. Holo USB is fine, but that doesn't mean everyone wants to use it.

 

I own both an SU-1 and Spring L3.  The primary benefit to using the I2S input is that it supplants the Spring's dirt-cheap [audio sample] clocks with the Crystek CCHD-575 clocks of the SU-1.

Beyond that there is not a lot particularly better about the SU-1's USB input versus that of the Spring.  (Both USB inputs are bus-powered and benefit similarly from better than noisy, leakage-filled computer VBUS.)

[Superdad]

16 hours ago, R1200CL said:

I wonder how easy it is to have the pure DSD stream in from HQPlayer or Roon as ethernet interface maybe with RAAT ?

Can that be the ultimate solution ?

 

Are you suggesting incorporation of an internal, Roon-endpoint, Ethernet>I2S/DSD interface board?  Care to name one available for OEMs?

 

Careful with that can of worms my friend.  

[Superdad]

11 hours ago, Miska said:

Do you have measurement data (Jtest-24 plots) if it actually improves performance? Because the clocks in my Spring L2 work fine (I posted the Jtest result earlier). Sending clock over a cable doesn't necessarily improve the end result...

 

I don't.  Obviously one would need to measure the combination of SU-1>Spring via I2S to compare to just the Spring alone.  

I suspect that a combination of factors is what results in better SQ with the SU-1>Spring. It is not huge, but it is noticeable.  Especially with power supply upgrades.  And this is fairly widely reported.

 

In the end, I enjoy the Holo Spring--it is flexible, musical, and reliable. But there are aspects of if that leave room for improvement (thinking of the analog output stage; and better clocking on-board).  Perhaps Jeff's next design---the "May" DAC I think--will carry it further. 

[Superdad]

22 hours ago, Miska said:

 

Probably not, but since the computer interface defaults to 32-bit, it is better to use something that actually matches the converter hardware instead of 32-bit... I have not seen clear spec about the conversion section, but I've understood from the posts that it would be 28-bit.

 

You could also try to set the DAC Bits to 20/21 to improve linearity, possibly with noise shaping. I need to run linearity test sweep on the PCM side at some point...

 

 

Hi Jussi:

 

Do you think setting DAC Bits lower also applies to those of us using the Singxer SU-1 DDC to output I2S to the Spring?

 

With past DACs (e.g. WaveIO>NOS PCM1704>discrete FET opamp) I had major revelations by reducing DAC bits as it really enabled HQ Player's dithering options to work and shine through.

 

I am traveling, so I can not look to check what DAC Bits setting I have been using with my SU-1>Spring Level 3.

 

Best holiday wishes to all,

--Alex C.

[Superdad]

3 hours ago, Bimmer100 said:

Please be sure you are loading the firmware to the correct usb module. Instructions are included. This firmware update applies to models that have the Xu208 xmos module. Not the earlier xmos U8 module found in early Spring v1 dacs. 

 

Does it have any effect on the DAC (SQ?) if one is using the Spring's I2S input?  In other words, is this only firmware for the XMOS chip? I am assuming so.

[Superdad]

4 hours ago, barrows said:

Oh yeah, I live in a rural area on 3 acres, so if I want to play TOOL (or Anne-Sophie Mutter) at 2 AM at 90 dB average levels, i can, and often do.

Oh come on Barrows, we know that you play TOOL at a LOT louder than 90 dB! 

[Superdad]

7 hours ago, barrows said:

I am fine with using HQP volume control, as long as there is no risk of it going to full scale via a computer software glitch.

 

Well the scary part of using the HQP volume control is that it allows you to go around the bottom of the "horn."  That is, if you turn it all the way down, the GUI allows you to accidentally keep going counter-clockwise--right to max volume!  I truly wish Jussi would fix that at I can not see any useful purpose served by allowing such.

[Superdad]

12 hours ago, asdf1000 said:

Is the Spring1 and Spring2 based on your open DSC1 Open Hardware design

4 hours ago, Miska said:

So you need to differentiate between actual design and principle of operation.

Shift-register DAC design can be executed in a number of ways (and to different levels), including choice to do the FIR in analog or digital domain.

[Superdad]

I see that Holo uses Intel/Altera FPGAs—on both their main board and on the USB input board.  There is a severe global shortage of Altera MAX FPGAs as Intel is using their production spots (with their fab house partners) for larger processors and CPUs. Lead times for Altera. FPGAs now stretch into 2024.

Unless Holo bought enough stock to carry them forward, they may soon need to pause, learn a different development platform, and rewrite all their code to suit a more readily available FPGA series from a different manufacturer. And that takes time.
 

This is what happened to UpTone recently—which forced the discontinuation (for now) of our popular UltraCap LPS-1.2 and has slowed down design work on a important new USB product we have been developing for nearly a year. [We are in the process of shifting to the small, innovative FPGA-focused firm Efinix (https://www.efinixinc.com/)?]
 

The Holo Spring 3 looks terrific, but those on the fence may be wise to get one sooner than later… 

[Superdad]

3 hours ago, Miska said:

macOS CoreAudio engine is doing the rate conversion.

And last I checked--about 10 years ago--CoreAudio SRC sounds truly dreadful. Any insight into what sort of filter parameters they use?