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WolfX700 Measurements of Holo Audio Spring 2 Lv2

WolfX-700

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I've measured many Holo Audio products before, including DACs like Spring, May, and preamps / headphone amplifiers like Azure. But all these measurements are either borrowing a device from a friend or borrowing a device from a developer.

Today I'm finally going to measure the Holo Audio equipment I bought! Because of my personal values (and the money in my wallet), I did not buy May, but chose Spring2 Lv2.

Look at things first:

Photo.jpg


Rear.jpg


Because the difference between Spring 2 and Spring in the chassis is very small (and there is almost no improvement), I decided to directly copy the previous comments on Spring's chassis:

I think this is a big and heavy unit. The case is made of 5 mm thick aluminum alloy - I think it is 6061 from the touch.

I like the white dot matrix LED display. However, the color matching of the buttons and side panels should still be reconsidered.Because their colors are too bright and too light. It has an adverse effect on the overall texture. Make the entire seemingly serious unit frivolous.

The button doesn't feel good enough either. Pressed sounds and feedback are not enough to match the price.

The USB and I2S inputs accept PCM data up to 32/1536 and DSD1024, the S/PDIF inputs up to 24/192 and DSD64. The outputs are balanced (XLR) and single-ended (RCA).

Looks almost the same, right?

On Holo Audio's webpage, it is claimed that Spring2 improves small signal performance over Spring.

Let's take a look at the measurement:
Dashboard48.jpg


Dashboard96.jpg

I found three things in the dashboard:
First, the maximum output level has decreased compared to Spring
Second, the two channels are slightly different.
Third, the performance under 96K is better than 48K, and SINAD under 96K exceeds the number of 110

In this age of constantly increasing output levels, it is quite rare for a modified product to reduce the output level.

As for the difference between channels, the developer said that it is because of the need to "Run in". Regardless of him, there is a difference in the correctness.


I was impressed by the low power supply noise on the dashboard, so I did a 1.2M length FFT (16 averages):
1K-FFT-Spectrum.jpg


Wow! I have to say that this image looks much better than Spring!

Let's continue:

Dynamic-Range---No.jpg

Linearity-(-20.jpg

THD+N-Ratio.jpg
SMPTE-Ratio.jpg
Multitone.jpg


As a discrete R2R, the performance of this device (if I haven't measured May and Spring before) is impressive enough.

As for the discrete R2R itself, is there any better sound? I don't want to discuss this kind of problem ...

I bought it as a "measurement device"-considering that it has no PLL, the jitter from the front-end equipment can be easily seen, and there are many interfaces that can be connected to various front-ends for analysis. It should be a good "detector".
 
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Thank you @WolfX-700
Is there a J-Test as on Spring 1 :)?

I listened to this Spring 2 and have nothing bad to say about its sound !
 
Interesting how this device has spiky distortion, but virtually zero mains noise. But also from the same company, a device with virtually zero harmonic distortions, but spiky mains noise..

One day we'll get both sides equalized ;P
 
Interesting how this device has spiky distortion, but virtually zero mains noise. But also from the same company, a device with virtually zero harmonic distortions, but spiky mains noise..

One day we'll get both sides equalized ;P
Yes, I am very dissatisfied with the power noise performance of Azure!
 
I bought it as a "measurement device"-considering that it has no PLL, the jitter from the front-end equipment can be easily seen

Huh? The AK4118 chip is very much doing PLL. Not to mention the AK4137 ASRC. What am I missing? These are Spring 1 pictures, did things change in Spring 2?
 

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Since that you own the unit itself, I hope you'll revisit the idea of running an FFT at DSD1024 bitrate. I guess you can use Sox to generate the needed tones.
 
How much did this thing cost you?

Still more harmonics than I'd like to see, despite the low THD number.
 
And? The fact that abnormal jitter gets through doesn't mean there is no PLL.
 
And? The fact that abnormal jitter gets through doesn't mean there is no PLL.

For me, the fact is that when encountering jitter, Spring and Spring2 can be directly reflected in the spectrum and other measurement results.
 
For me, the fact is that when encountering jitter, Spring and Spring2 can be directly reflected in the spectrum and other measurement results.

I think the same can be said about any DAC that doesn't employ ASRC or special 2 step PLLs. Some ESS based DACs allow to disable jitter correction and run the ESS chip clocked by SPDIF, pretty much to the same effect.
 
I think the same can be said about any DAC that doesn't employ ASRC or special 2 step PLLs. Some ESS based DACs allow to disable jitter correction and run the ESS chip clocked by SPDIF, pretty much to the same effect.

You're right, and the point of the question is-I have to make up a little reason to buy something to make my wife complain less;)
 
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You're right, and the point of the question is-you have to make up a little reason to buy something to make my wife complain less;)
Lol :p now the truth comes out.

I understand though. If I'd buy one pricy DAC it'd be a holo spring. They look (and weigh!) the part.
 
Years after it's release, this still takes the cake for me (and I feel will for more years still) in terms of build quality:

00067426.jpg
There is no doubt that Matrix's chassis build quality is one of the best in China-made DACs.
 
Interesting how this device has spiky distortion, but virtually zero mains noise. But also from the same company, a device with virtually zero harmonic distortions, but spiky mains noise..

One day we'll get both sides equalized ;P
Maybe having both transformer and IEC inlet in it's own section helps reduce mains noise?
holo-spring.jpg
 
There is no doubt that Matrix's chassis build quality is one of the best in China-made DACs.

Best period, if you ask me personally. Most others look like a generation behind if you ask me. Sure maybe you can dig up expensive multi $10,000 devices, but even then I'd still take the gamble and wouldn't say it's this clean, or well finished inside and out.
 
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