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Okto dac8 stereo DAC Review

Matias

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@amirm would you mind measuring jitter and multitone for the Ethernet and wifi inputs, just to compare the onboard Pi4 to the excellent measurements of the USB input? Thanks!
 
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Thread Starter #122
@amirm would you mind measuring jitter and multitone for the Ethernet and wifi inputs, just to compare the onboard Pi4 to the excellent measurements of the USB input? Thanks!
I can't. My jitter test is 24 bits and airplay truncates that to 16. It also resamples it to 44 kHz which really screws it up.
 

beefkabob

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Yes the only thing that matters is the SINAD coming out of the binding posts of the final amp in the system. That result will be identical from the binding posts of the Purifi or Benchmark AHB2 regardless if the $20 Meizu or the Okto DAC was used as a source.
I'd like to see the test, just to make the point. A Purifi and an ABH2 hooked up to a steller vs merely fantastic DAC, and measure the output.

What this DAC lacks is room correction.

Is it still possible to get the Dirac laptop software?
 
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Is it still possible to get the Dirac laptop software?
Yes, but it only comes as a VST plug-in so you need a host app for it.
 

RichB

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Since I’ve been only using Roon lately, I plan to set it up with RoPiee XL like I currently do with my Pi 3b+.
I tried that and it crashed my network when using WiFi, so I switched to Volumio.

- Rich
 

RichB

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I can't. My jitter test is 24 bits and airplay truncates that to 16. It also resamples it to 44 kHz which really screws it up.
I had trouble consistently connecting to the Roon endpoint because Roon was selecting AirPlay.

You should be able to get Volumio to accept full resolution by adjusting the settings as shown below:

Install the Roon Bridge
1594773589346.png

Disable other sources:
1594773778754.png

Once enabled in Roon, you can stream full resolution audio files.

- Rich
 

JohnYang1997

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@amirm Was the bandwidth correct for the dashboard? Would you provide a full screen screen shot where you have the settings for the input?
Thanks in advance.
 

JohnYang1997

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4270056f465aa319.png
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These are AP loopback with different bandwidths. As I measured yesterday the output noise is far lower than the equivalent input noise. So the limitation should apply to DAC measurements too. Is the 1 extra dB coming from the different bandwidth?
Another thing is that the dynamic range measurement only showed 127dB, which is the same as element x. So it can't be that noise is far lower on this.
@amirm Is the bandwidth used for dashboard correct?
 
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View attachment 73368 View attachment 73369
These are AP loopback with different bandwidths. As I measured yesterday the output noise is far lower than the equivalent input noise. So the limitation should apply to DAC measurements too. Is the 1 extra dB coming from the different bandwidth?
Another thing is that the dynamic range measurement only showed 127dB, which is the same as element x. So it can't be that noise is far lower on this.
Not sure why people pay $30k for an APx-555. I can measure SINAD up to 128 up to 24v, and 116 SINAD up to 100v up to from 20hz to 100khz. And I have only $5K into my setup. Lots of suckers out there!
 

JohnYang1997

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Not sure why people pay $30k for an APx-555. I can measure SINAD up to 128 up to 24v, and 116 SINAD up to 100v up to fromm20hz to 100khz. And I have only $5K into my setup. Lots of suckers out there!
What about THD of -140dB? And you can build a noise amplifier for 30 bucks. Then you can measure 140db of SINAD indirectly across wide range of frequencies.
And highly precise frequency, highly precise amplitude. And many more
Maybe you don't really need it for designing a great product but you can't say it sucks and people who have those are suckers....
 

pozz

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Not sure why people pay $30k for an APx-555. I can measure SINAD up to 128 up to 24v, and 116 SINAD up to 100v up to from 20hz to 100khz. And I have only $5K into my setup. Lots of suckers out there!
Please prove your results by starting a new thread and showing measurements.
 
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What about THD of -140dB? And you can build a noise amplifier for 30 bucks. Then you can measure 140db of SINAD indirectly across wide range of frequencies.
And highly precise frequency, highly precise amplitude. And many more
Maybe you don't really need it for designing a great product but you can't say it sucks and people who have those are suckers....
My rig can outperform the APx-555 in every area up to 100khz. Far far beyond the threshold of audibility for $5k.
 

Doodski

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Not sure why people pay $30k for an APx-555. I can measure SINAD up to 128 up to 24v, and 116 SINAD up to 100v up to from 20hz to 100khz. And I have only $5K into my setup. Lots of suckers out there!
The value of metrology sometimes appears bloated but standards are to be referenced and that costs bigger money.
 

YSC

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Given that the only amp whose SINAD exceeds the Eval 1 with its buffer bypassed (108 db) is the Benchmark AHB2 (113db), are you saying that this unit is overbuilt for absolutely every amp out there?
As a tech noob I am thinking of one question:
Shouldn’t the source SINAD is always higher the better even the amp is less competent than it? As we have no absolute distortion free stuffs and what we hear is the SINAD sum from dac to amp to speaker or headphone. As the distortion at any frequency can be distorted multiple times. So it won’t be a 100db SINAD amp should only use a dac at same grade ?
 
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The value of metrology sometimes appears bloated but standards are to be referenced and that costs bigger money.
My rig is perfectly calibrated against a reference far beyond an APx-555. Every analyzer manufacturer has a reference rig they use for calibration.
 

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