Review and Measurements of Okto DAC8 8Ch DAC & Amp

[nm4711]

Interesting learning from setting up the DAC8 DSP with LXmini+2: have to pay attention to the extremes. I'd copied over the settings from the miniDSP 4x10HD to the nanoSHARC. Everything seemed fine except for bass heavy tracks where I had massive distortion. I noticed the sub channels were outputting over 0dBFS which was the cause. As the nanoSHARC has no volume control everything is running full-bore, while the volume control for the 4x10 is done in the DSP.

Previously I'd thought the subs were reaching their max and distorting at higher levels, but it turned out I could get far more SPL out of them cleanly with the nanoSHARC setup. With my amps the 4x10 was exceeding 0dBFS with certain tracks when the volume was higher than ~-15dB. Makes me wonder how many other people are bumped in to that implementation issue and don't know it.

I'am using a miniSHARC (at full volume) with the DAC8 and a pair of LXmini+, not LXmini+2. I don't think I have this problem. But maybe I don't listen to bass heavy tracks or the +2 Subs are boosted more than the + subs. But I have to check it these days.

 

[g29]

...
And yes Aesthetics are last on the list,although they are very important as we do have to look at the device.
...

FWIW, OR stated they have 2 flashes and the ability to field update both for future firmware updates. If the display font software is upgradeable, maybe they can tweak the fonts in a subsequent firmware release if it becomes a issue. With that being said, I would rather them give any audio firmware related changes first priority.

 

[nm4711]

I'd love to see a great DSP crossover for the Linkwitz LX521 and other multi-driver systems. However, I'm not sure there's anything out there that will outperform an analog active crossover yet. Basic DACs are only now getting to the point where the distortion is inaudible. Digital audio is different than analog distortion, where it takes only a small amount of distortion to sound nasty and unnatural. Trying to do a multi-way crossover in real time using DSP would seem like a real engineering challenge to get it right. Hopefully, some of these new smaller manufacturers will surprise us with innovation in that area. I do wonder if there's enough demand for that to happen.

With DACs like the DAC8 and a proper DSP I don't see any problem.

 

[SpyB]

@SpyB Don't get me wrong - I'd love it if it were a full-color OLED display - and touchscreen at that - but I wouldn't expect to see it at this price point with this feature set. I could be wrong but to my knowledge this is the least expensive and most performant 8-channel DAC on the market currently (at least outside of horribly measuring AVR/PrePro versions) - and most of those have crappy displays as well.


It wouldn't cost $200 for them (Okto)... but there's two of them (one on each side) and if you add in volume requirements... $200 might actually be on the low side. You're welcome.

Yes horribly measuring is very appropriate comment, we can trust no reviews or sales people/if it was not for Amir and ASR we would still be in the dark.This site has made me so aware of all the times I have been ripped off,the consolation being that it will never happen again because of ASR and Amir
And I am deeply Thankful for that

 

[pos]

FWIW, OR stated they have 2 flashes and the ability to field update both for future firmware updates. If the display font software is upgradeable, maybe they can tweak the fonts in a subsequent firmware release if it becomes a issue.

Agreed, they could simply choose a font better suited for low DPI.

 

[SpyB]

FWIW, OR stated they have 2 flashes and the ability to field update both for future firmware updates. If the display font software is upgradeable, maybe they can tweak the fonts in a subsequent firmware release if it becomes a issue. With that being said, I would rather them give any audio firmware related changes first priority.

I like the way your mind works,a excellent suggestion

 

[SpyB]

Agreed, they could simply choose a font better suited for low DPI.

"choose a font better suited for low DPI"
another excellent suggestion

 

[Neddy]

Assuming Pavel had/has the time to consider display upgrades, the question would be, would you wait 6 more months (or a year) to get the DAC you've ordered, and pay more for it? I would NOT. In my view he should put this request on the back burner.

The design simplicity & elegance that he has achieved with these products (while maintaining world class performance) is not easy to do, so unless upgraded display boards were drop-in both hardware and software wise - more time, more money, more headaches for him...esp at at time when he has existing customers and likely new ones clamoring for product.

If an upgrade kit were made available after he catches up with back-orders, I might consider it, but since mine will live in a rack, and the ability of my eyes to resolve details like that at 10' is questionable, I probably wouldn't spring for it.
(I wonder if adding color features would improve usability significantly - it might.)

When I was involved in new product dev and releases, a rough rule of thumb we used was that any new part added to the design late in it's development life would add at least 10x it's purchase cost to the product price.
So only (the very few) design 'adds' that improved several factors, like marketability (sales forecasts), ease of manufacturing, and (lastly) reliability/useability made it to the Maybe List. (Those that reduced cost of manufacture did get priority.)

On the other hand (to your point), ignoring good ideas/suggestions from potential buyers would be a very bad thing...though I'm not quite sure 'better display' qualifies as a seriously functional improvement, though it would be a minor aesthetic one for sure.
(The availability of 'second guessing' on product development via the innernet does bring to mind the old saw of 'an elephant is a mouse designed by a committee'!)

Last thought - I have other gear (also rack mount) that have what would be considered poor displays, but one of them is set and forget, while the other has 'an app' - so I never use either after initial set up.
Since this is an 'app-less' (hah hah) device, display use might be more frequent (certainly volume settings!), so in that respect improvements (esp ones that might improve readability at a distance) might be of interest.

Anyway, thanks for taking the time to make the case for it, and provide some very nice display examples.

 

[josh358]

Either way (USB or S/PDIF) the synchronization problems would exist. One would need some kind of master clock tying them all together.

There are synchronization problems with USB, to be sure, since the DAC's clock is the master. But SPDIF/AES3 is clocked by the input signal, with a PLL, so multiple DAC's will run synchronously. If they're of different makes, they will probably have different latencies, but this can be compensated in software (although latency can have varying relations to sample rate so probably best done at lower frequencies if different DAC's are involved).

I've used multiple DAC's of different kinds with AES3 and it works just fine.

 

[JP]

I'am using a miniSHARC (at full volume) with the DAC8 and a pair of LXmini+, not LXmini+2. I don't think I have this problem. But maybe I don't listen to bass heavy tracks or the +2 Subs are boosted more than the + subs. But I have to check it these days.

Try Hey Daddy by Usher. I had to attenuate the nanoSHARC inputs -14dB to get that to stop clipping. I ended up with +5dB in Roon due to volume normalization, -18dB at the nanoSHARC inputs, and +18dB boost turned on in the dac8. I've the AHB2 on low gain and the dac8 outputs +24dBu. That puts the volume control at -18dB at the loudest I'll listen, typically -22dB to -20dB. Leaves me some room for tracks where the normalization appears off, or vinyl that's cut a bit cold.

 

[SpyB]

Assuming Pavel had/has the time to consider display upgrades, the question would be, would you wait 6 more months (or a year) to get the DAC you've ordered, and pay more for it? I would NOT. In my view he should put this request on the back burner.

The design simplicity & elegance that he has achieved with these products (while maintaining world class performance) is not easy to do, so unless upgraded display boards were drop-in both hardware and software wise - more time, more money, more headaches for him...esp at at time when he has existing customers and likely new ones clamoring for product.

If an upgrade kit were made available after he catches up with back-orders, I might consider it, but since mine will live in a rack, and the ability of my eyes to resolve details like that at 10' is questionable, I probably wouldn't spring for it.
(I wonder if adding color features would improve usability significantly - it might.)

When I was involved in new product dev and releases, a rough rule of thumb we used was that any new part added to the design late in it's development life would add at least 10x it's purchase cost to the product price.
So only (the very few) design 'adds' that improved several factors, like marketability (sales forecasts), ease of manufacturing, and (lastly) reliability/useability made it to the Maybe List. (Those that reduced cost of manufacture did get priority.)

On the other hand (to your point), ignoring good ideas/suggestions from potential buyers would be a very bad thing...though I'm not quite sure 'better display' qualifies as a seriously functional improvement, though it would be a minor aesthetic one for sure.
(The availability of 'second guessing' on product development via the innernet does bring to mind the old saw of 'an elephant is a mouse designed by a committee'!)

Last thought - I have other gear (also rack mount) that have what would be considered poor displays, but one of them is set and forget, while the other has 'an app' - so I never use either after initial set up.
Since this is an 'app-less' (hah hah) device, display use might be more frequent (certainly volume settings!), so in that respect improvements (esp ones that might improve readability at a distance) might be of interest.

Anyway, thanks for taking the time to make the case for it, and provide some very nice display examples.

Hi Neddy,
you have put a lot of thought into this post/with a lot of positive comments.
Thank you for the time you have taken to compose it

 

[Rja4000]

I've had the RME ADI-2 DAC now for about 3 months and really love it with my current setup (MacBook pro with JRiver streaming music over usb to the DAC, DAC directly driving a Benchmark AHB2 amp, and Buchardt S400 speakers). 2 of the features on the RME I've come to rely on are the auto ref level (mechanism to set the reference level automatically in order to maximize SNR as volume is adjusted) and the loudness feature (they allow the user to set the level at which the loudness adjustment starts to be gradually applied making it easy to tailor the adjustment to your listening environment). @Okto Research Are there any plans in the roadmap to implement features like the RME's auto reference level and loudness for the DAC8? Also is there a manual available for the DAC8? I couldn't find one on the website.

I'm about to upgrade my setup to 4.0 . I already have the rear speakers ordered and have a second AHB2 that just arrived. All I need now is a multi-channel DAC. I'm trying to choose between the Okto DAC8 or buying an RME ADI-2 Pro FS which can be combined with my ADI-2 DAC to form a multi-channel DAC (the Pro FS can act as master and sync clock of the ADI-2 DAC over SPDIF and I can use CoreAudio to aggregate the 2 into a single device for JRiver).

Are you aware that the RME ADI-2 pro has four independent analog outputs ?
(when the source is USB)

 

[Ozymandias]

Are you aware that the RME ADI-2 pro has four independent analog outputs ?
(when the source is USB)

Yes I am. Though only channels 1/2 are available via XLR/TS outputs at the back. The second pair of independent analog outputs is only available via the the 3/4 headphone jack at the front (though a splitter cable can be used for
non-headphone connection). I was considering the combination of the pro fs wth my existing adi-2 dac since I’ll need to support 5.1 in future. However the okto dac8 seems a more straightforward fit for my needs. I just wish the manual for the currently shipping version of the okto dac8 were available. That would help in making a decision

 

[nm4711]

Try Hey Daddy by Usher. I had to attenuate the nanoSHARC inputs -14dB to get that to stop clipping. I ended up with +5dB in Roon due to volume normalization, -18dB at the nanoSHARC inputs, and +18dB boost turned on in the dac8. I've the AHB2 on low gain and the dac8 outputs +24dBu. That puts the volume control at -18dB at the loudest I'll listen, typically -22dB to -20dB. Leaves me some room for tracks where the normalization appears off, or vinyl that's cut a bit cold.

I've tried it. Most of the times my woofer channels are nearer to digital clipping but do not clip. They reach like -2 or -3 dB. The sub channels are typically much lower, but 4 or 5 times they reach -1 dB for a fraction of a second. So no digital clipping as far as I can tell. Interestingly the left woofer and sub channels are sometimes 5 dB higher than the right channels and both drivers are doing some heavy excursion. So there seems to be some subsonic content in the left channel..

I don't use any kind of dynamic normalization and the digital signal is not boosted or attenuated on it's way to the DSP. DSP inputs are at 0 dB and the subs are boosted by ~15 dB at the low end.

If you want to do some more investigation we should open a separate thread I guess.

Greetings

 

[Okto Research]

So I think OKTO are putting a lot of effort into the electrical and mechanical design
of their DAC,and the display should not let it down.

If it costs more to implement a very high resolution display,so be it
do it, and charge a bit more to compensate for the cost, or give the purchaser
the option

Here are some DAC's that have very good display's,and I am not referring to the size
or color of the display,only to the clean font's presented to show that such a display
exists.

I do not think these DAC's are worth the money,
Ideon about 18,000US
resonessencelabs $6000US

Although they do show that a clean clear display is possible,and I do not think
the purchase price is because of the display.

I could have posted images,although images can be deceptive/so here are video's
that show the display's mentioned in the flesh.

(Ideon Absolute DAC)

(Ideon Absolute DAC)

(Invicta) display is at 4m 30sec

The OPPO HA-1 also had a very good display and did not cost anywhere near the asking price of these DAC's
So I think that a better display is not a big cost factor in the design of a DAC or any device needing a display.

For too long we have been made to accept the antiquated dot matrix type of display or the jagged rendition
of fonts and numerals.

Time to change/Time to say NO!! I do not accept this and I want a better display

The decision to go with these displays was mainly because we really wanted OLEDs for their high contrast ratio and black rendering, so the entire active area of the display wouldn't produce a grey-ish glow when viewed in the dark as an LCD (albeit high-resolution) would. That is not something that can be judged by comparing pictures/videos on the internet unless a camera with fixed exposure was used. Another aspect is an optical bonding between the display itself and an acrylic/glass cover, so the light doesn't bounce back and forth between the two, which would again make the black background rather grey-ish.

The decision was not cost-driven, in fact OLEDs of this size are not particularly cheap. The scaling with 128x64 resolution is by no means intended for a close-up view, but instead to be viewed from a listening position, from where it provides a pretty good and crisp look we believe, especially in the dark.

So no plans to change the displays anytime soon, in fact there is a lot we can do with the existing ones thanks to the possibility of field SW updates (for the DAC8 PRO and the upcoming DAC8 Stereo).

I just wish the manual for the currently shipping version of the okto dac8 were available.

Yes, the manual is in progress and will soon appear on the website.

Cheers,
Pavel, Okto Research

 

[777]

Wich op-amp is used for I/V conversion ?

 

[SpyB]

The decision to go with these displays was mainly because we really wanted OLEDs for their high contrast ratio and black rendering, so the entire active area of the display wouldn't produce a grey-ish glow when viewed in the dark as an LCD (albeit high-resolution) would. That is not something that can be judged by comparing pictures/videos on the internet unless a camera with fixed exposure was used. Another aspect is an optical bonding between the display itself and an acrylic/glass cover, so the light doesn't bounce back and forth between the two, which would again make the black background rather grey-ish.

The decision was not cost-driven, in fact OLEDs of this size are not particularly cheap. The scaling with 128x64 resolution is by no means intended for a close-up view, but instead to be viewed from a listening position, from where it provides a pretty good and crisp look we believe, especially in the dark.

So no plans to change the displays anytime soon, in fact there is a lot we can do with the existing ones thanks to the possibility of field SW updates (for the DAC8 PRO and the upcoming DAC8 Stereo).


Yes, the manual is in progress and will soon appear on the website.

Cheers,
Pavel, Okto Research

Thank you,for your explanation of the Okto display/in my case I would be using in a desktop situation and it would be very hard to use it
with the jagged looking font. Has the display the option to turn it of when not needed.

And although you have no plans to change the display,and I would not expect that to happen,
do you think that the jagged font could be improved on/or is that how it will always be.

Once again,thank you for your response

 

[wineds]

Thank you,for your explanation of the Okto display/in my case I would be using in a desktop situation and it would be very hard to use it
with the jagged looking font. Has the display the option to turn it of when not needed.

And although you have no plans to change the display,and I would not expect that to happen,
do you think that the jagged font could be improved on/or is that how it will always be.

Once again,thank you for your response

Very hard to use it? Seriously?

 

[SpyB]

Very hard to use it? Seriously?

I was referring to reading the display close up/not to actually using the DAC.
I guess I should have been more specific.

 

[wineds]

You think the display will be hard to read up close? You cannot be serious?