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Review and Measurements of Okto DAC8 8Ch DAC & Amp

josh358

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So completely irrelevant in casual listening and that there are no "night and day" differences between competently engineered DACs unlike what faith-based audiophiles like to claim all the damn time?
Absolutely. As Amir pointed out, audiophiles are often surprised when the major differences they thought they heard disappear in a blind test, or for that matter any level-matched A/B test. I've experienced that phenomenon myself, even though I'm aware of it.
 
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somebodyelse

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Isn't WSL just a virtual machine/emulation layer (similar to WINE on Linux or Parallels on MAC) ? Cygwin has been around for decades. Installing a VM isn't replacing the underlying core OS.

Also, the variance between BSD and Linux is about the same as in different Unix (BSD and non-BSD) variants. Linux and Unix are basically the same thing (except for the open/closed free/pay source aspect). Porting code between Linux/Unix/BSD is a lot easier than between (Linux/Unix/BSD) and Windoze.
If you want a detailed answer please start a new thread for it - we're well off topic here.
 
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Okto Research

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Hi
Thanks for your answer.
I'm not sure I understand it though.
I'm interested to be able to either use it in stereo mode, with maximum SNR, or in 8 channels mode when needed.
What's required to be able to do that then?
I guess only the Pro model has 8 channels AES, so that's the one I'm interested in.
Is there a way to increase its performance on a single stereo output? And, if yes, how?
We have thought about implementing this in the DAC8 PRO, but it would require relays with their shortcomings (since I am not aware of any semiconductor-based analog switch with low-enough THD).

The easiest way is just to simply connect the required number of channels together externally (DAC8 PRO outputs don't mind that). Each doubling of the number of summed channels will cause sqrt(2)-times decrease in RMS noise value due to its uncorrelated nature and normal distribution.

Because the full-scale output voltage remains the same, this results in 3dB dynamic range improvement for 2 summed channels, 6dB for 4 channels and 9dB for 8 channels (mono operation), pushing the dynamic range from the original 125dB to 128dB, 131dB or 134dB respectively (or reducing the RMS noise value from the original 2.4uV RMS to 1.7uV, 1.2uV or 0.84uV). Channel routing needs to be set appropriately in the menu.

By the way, I'm a bit puzzled by your rack mount.
Does that mean the device will require 2U???
That's a bit if a show stopper if that's the case.

The DAC8 front panel is 50mm in height, so 1U mounting is not possible unfortunately. The provided mounting brackets are 2U, but if there is enough interest, we could make a 1U variant for racks with sliding mounting points where equipment can be mounted offset from each other.

Pavel, Okto Research
 
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Bliman

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We have thought about implementing this in the DAC8 PRO, but it would require relays with their shortcomings (since I am not aware of any semiconductor-based analog switch with low-enough THD).

The easiest way is just to simply connect the required number of channels together externally (DAC8 PRO outputs don't mind that). Each doubling of the number of summed channels will cause sqrt(2)-times decrease in RMS noise value due to its uncorrelated nature and normal distribution.

Because the full-scale output voltage remains the same, this results in 3dB dynamic range improvement for 2 summed channels, 6dB for 4 channels and 9dB for 8 channels (mono operation), pushing the dynamic range from the original 125dB to 128dB, 131dB or 134dB respectively (or reducing the RMS noise value from the original 2.4uV RMS to 1.7uV, 1.2uV or 0.84uV). Channel routing needs to be set appropriately in the menu.



The DAC8 front panel is 50mm in height, so 1U mounting is not possible unfortunately. The provided mounting brackets are 2U, but if there is enough interest, we could make a 1U variant for racks with sliding mounting points where equipment can be mounted offset from each other.

Pavel, Okto Research
First thanks for the information. Can you give information if the volume knob will be different on the stereo dac?
 

Okto Research

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First thanks for the information. Can you give information if the volume knob will be different on the stereo dac?
Mentor, the current knob manufacturer, left our messages without a reply and the only good looking knob for our use case in their catalog seems to be just a render, not an actual product. We are thinking about designing and making our own knob.

@Okto Research

Question: would the trigger output of the DAC8 be able to power a relay? Something like this [link]? I cannot find the trigger voltage on your website, but in case of 5V the max specified current is 190mA.

Is the trigger output fully isolated from the rest of the unit? I am curious whether this scheme could introduce noise inside the unit.

The DAC8 PRO trigger provides 5V logic output referenced to the PE (chassis) and is able to supply 15mA of current. It is not isolated and there is no need for that - it is up to the receiving side to do that if the isolation is needed. The module from your link should work just fine as it seems to need 5mA and it even has an optocoupler on the trigger input. It has does need a separate power supply though (like a wall adapter).
 

Bliman

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Mentor, the current knob manufacturer, left our messages without a reply and the only good looking knob for our use case in their catalog seems to be just a render, not an actual product. We are thinking about designing and making our own knob.



The DAC8 PRO trigger provides 5V logic output referenced to the PE (chassis) and is able to supply 15mA of current. It is not isolated and there is no need for that - it is up to the receiving side to do that if the isolation is needed. The module from your link should work just fine as it seems to need 5mA and it even has an optocoupler on the trigger input. It has does need a separate power supply though (like a wall adapter).
Thank you for the info
 

6speed

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Without the option for an onboard Nanosharc, what are the best options for feeding stand alone DSP (not a PC) output into the DAC8?
 

digitalfrost

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Anything with analog inputs is out of the question, else you wouldn't need to buy DAC8 if you put an inferior AD/DA strage in front of it. So any standalone DSP with digital inputs. Something like miniDSP 2x4 HD maybe? Of course for 8 channels, you'd need multiple.
 

g29

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Mentor, the current knob manufacturer, left our messages without a reply and the only good looking knob for our use case in their catalog seems to be just a render, not an actual product. We are thinking about designing and making our own knob.

What is the knob in your image below ? Is it just a rendering ?

What other things are holding up the production shipments ?

index.php
 

Labjr

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Anything with analog inputs is out of the question, else you wouldn't need to buy DAC8 if you put an inferior AD/DA strage in front of it. So any standalone DSP with digital inputs. Something like miniDSP 2x4 HD maybe? Of course for 8 channels, you'd need multiple.

Mini DSP doesn't outperform an analog active crossover. So pretty useless. Would be good to see a DSP crossover that has the specs of some of these inexpensive DACs, to use with the Linkwitz LX521 speakers.
 
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6speed

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The trick is getting 8 channel digital output from any DSP into the Okto
 

audimus

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What is the canonical (typical or common) usage scenario of this unit? What connects to it for in and for out?

Who is the target customer?
 

escalibur

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What is the canonical (typical or common) usage scenario of this unit? What connects to it for in and for out?

Who is the target customer?
I wish they would release a smaller / basic version for stereo and headphone usage only. Nothing less nothing more.
 

mk1classic

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What is the canonical (typical or common) usage scenario of this unit? What connects to it for in and for out?

Who is the target customer?
This is the ideal product for us who build active speaker with computer based DSP. 8-channels of individual input through either USB or via a sound-card with digital output according to AES-EBU standard. This is not your standard DAC for use with a pre-amp or integrated amplifier.
 
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6speed

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DSP and DAC would likely need to be integrated.

Right, which is why it made sense when they had a version with an integrated Nanosharc. On the other hand, I would prefer to have the flexibility of separating the DSP and DAC separate because I think the DAC may have a longer lifespan in my system (DSP technology is advancing more rapidly). However, I can't find a suitable DSP to use with the Okto. The older Minisharc is still available, and one may be able to add 4x Digi-FP boards to get AES/EBU out to the Okto.
 

Kal Rubinson

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What is the canonical (typical or common) usage scenario of this unit? What connects to it for in and for OUT?
Out is easy. Either (1) a multichannel speaker array, (2) a couple of multiway speakers or (3) a pair of 3ways + subs.
For IN, I see any computer-based DSP processing with multiAES3 outputs (rare) or USB output via a miniDSP U-DIO8.

Who is the target customer?
Me, for one. :)
 

Labjr

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Right, which is why it made sense when they had a version with an integrated Nanosharc. On the other hand, I would prefer to have the flexibility of separating the DSP and DAC separate because I think the DAC may have a longer lifespan in my system (DSP technology is advancing more rapidly). However, I can't find a suitable DSP to use with the Okto. The older Minisharc is still available, and one may be able to add 4x Digi-FP boards to get AES/EBU out to the Okto.

Metric Halo and other companies make boxes with integrated DSP and ADC/DACs. Metric Halo makes upgrade modules available every few years. Great company. But really pro level stuff.
 

MWC

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I'm considering the Okto DAC8 for use with:
OUTs = 4x Adam A7 (powered monitors with xlr input)
INs = PC/NAS LAN > USB using Foobar2000, ASIO driver, Custom Channel Mapping

I hope I have understood that this would work. Otherwise please enlighten me.
 
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