HOLO Audio Spring DAC - R2R DSD512

[pkane2001]

40 minutes ago, matthias said:

 

The newer one should be this:

https://wildism-audio-hk.myshopify.com/blogs/news/holo-audio-xmos-xu208-spring-dsd-r2r-dac

 

Matt

 

Thanks, I think I may have the older one based on this, since I bought it in 2017. I also see the updated board available from Tim:

 

https://kitsunehifi.com/product/holoaudioxu208usbmodule/

 

But based on what I measured, I don't see the need to upgrade 

[pkane2001]

5 hours ago, Miska said:

 

Here's Spring 1 with the old USB interface:

 

And here's Spring 2 with the new USB interface (before firmware update):

 

So the USB/clocks have become better in the newer version. But the old one is certainly not bad either! So I doubt this explains differences, or at least I would want to see measurement data with Singxer before I would be ready to spend 500+ EUR extra with assumption that it would improve the performance in this respect.

 

But this is just on my system, in both cases Spring being driven from the same HP Xeon workstation running Ubuntu Studio, over bog standard 10€ blue USB3 cable.

 

 

I’ve measured the original Holo Spring (old USB interface) with Singxer over I2S and without. No major differences in terms of jitter or additional spurae, but the noise floor increased compared to the direct USB connection. I didn’t spend much time investigating it, since the increase was well below the audible range. I’ll try to dig up those measurements, or maybe redo them if I can’t find them.

[pkane2001]

5 hours ago, barrows said:

Thanks Jussi.  Yes the same measurement via I2S from a SingXer interface (or ultraDigital, etc) would be interesting to see for sake of this conversation.

 

Here are a few comparisons of SU-1 -> I2S -> Holo and USB->Holo direct.

 

1kHz signal over USB (blue) compared to SU-1 (black). You can see the slightly elevated noise floor, as well as worse THD+N performance by about 2-3dB. Obviously extremely small differences at that level:

 

20 tone test . Orange is the SU-1 trace:

 

Comparing 12kHz J-test (SU-1 is the black trace):

Very comparable performance, except for an apparent lower noise floor without SU-1. SU-1 was powered from a battery and has the Sparkos voltage regulator mod.

 

[pkane2001]

33 minutes ago, pkane2001 said:

 

Here are a few comparisons of SU-1 -> I2S -> Holo and USB->Holo direct.

 

1kHz signal over USB (blue) compared to SU-1 (black). You can see the slightly elevated noise floor, as well as worse THD+N performance by about 2-3dB. Obviously extremely small differences at that level:

 

20 tone test . Orange is the SU-1 trace:

 

Comparing 12kHz J-test (SU-1 is the black trace):

Very comparable performance, except for an apparent lower noise floor without SU-1. SU-1 was powered from a battery and has the Sparkos voltage regulator mod.

 

 

Adding a jitter test with Holo Spring and LKS Audio USB-100 DDC in place of SU-1:

 

 

The same slightly elevated noise floor seems to be caused by the I2S input on Holo Spring, rather than by SU-1 or USB-100 DDC. USB-100 was also powered by a battery but is unmodified from stock.

 

[pkane2001]

16 minutes ago, barrows said:

So it shows worse performance via I2S vs. USB, as I would expect to see.  I could see how say might suspect he differences to be low enough to be inaudible, but my experience comparing measured jitter levels with listening tests suggest that this would be audible.  Just from this, I could see that some might find the I2S connection to produce a sound with slightly more body, albeit lower resolution.  Some listeners might indeed prefer the I2S connection in a given system context...  I know what I would think about it.

Certainly there is nothing here that would confirm better performance for I2S vs. USB.

 

Thanks Paul!

 

I do think that the differences I measured  are well below audible, but, as you say, there is nothing in them that demonstrates any improvement with an I2S-connected DDC.

 

I started out using SU-1 and even made many of the suggested mods to try to improve it, but in the end, I went back to using the straight-in USB connection on Holo Spring. And that was all before I decided to measure it

 

[pkane2001]

15 minutes ago, exdmd said:

Holo Audio May is not officially released yet but ASR managed to get a pre-release review sample supposedly out later this year. Since ASR believes DACs that measure well all sound the same there is absolutely no indication of how it sounds.

It sounds transparent

 

[pkane2001]

3 hours ago, Miska said:

 

With ASR's measurements, you really cannot say...

 

You measured Spring, as did I and found it to be a good performing DAC. ASR measurements show that May measures better in all respects, so I’d like to think that it really is at least as good as the Spring, likely better. But yes, not everything was measured. And it’s also outside my audio budget, so I also have only a passing interest.