Okto 8 Owner’s Thread

[Kal Rubinson]

And there is no other known multichannel DAC that measures well.

exaSound? Merging Hapi?

Sometime I think I am the only one who cares about multichannel.

Nope.

 

[Dacapalooza]

exaSound does not have aes inputs. So not easily compatible for 4k blu rays. Nor Trinnov. Merging Hapi has been tested? What is the SINAD?

 

[mdsimon2]

I googled if I can use 3 DAC's if DAC8 goes out of biz and it claimed:
A 6-channel (or 8-channel) DAC is superior to using three separate stereo DACs for multichannel audio due to synchronization, phase alignment, & they often suffer from drift and independent clock issues. And I just do not have rack space for 3 DAC's so rather not. Plus 2 more power cables.

If you are using AES input DAC(s), there is very little risk of clock drift as they will be clocked from the AES clock. You only need to worry about drift if the DAC is an exotic design with a FIFO buffer and local asynchronous clock.

Using identical DACs should eliminate any issue with different phase response (as they should have identical frequency response) and synchronization (as they should have identical delay), but assuming you have DSP capability to correct for differences in delay and frequency response using different DACs isn't a huge concern, especially in a multichannel (5.1/7.1) setup.

Michael

 

[Neddy]

If I had more expendable income I'd get a second Okto as well, it's an indispensable part of my audio system

With you on that, as well.
My experience with Okto has been great, even with a few initial teething and software issues, long since resolved.
(Not to mention that when I asked for volume control on the AES outputs (apparently not part of the spec), they managed to implement that in short order.)
My background in electronics mfging and new product development, gave me a pretty good idea of what to look out for in terms of 'flim-flam' - and Pavel just kept delivering (though slowly, sometimes).
I always considered it to be a bargain, regardless. And still do.
Now having atmos 7.1 delivered to it via AES (in addition to PC/USB/Jriver) is a sheer delight.
The phrase 'Hog Heaven' comes to mind
And all from Amir's early reviews on these machines!!
Thanks Amir and Pavel.

 

[ZeDestructor]

exaSound does not have aes inputs. So not easily compatible for 4k blu rays. Nor Trinnov. Merging Hapi has been tested? What is the SINAD?

MiniDSP has entered the ring with their HT, HTx and Tide16, though with the caveat of having to send audio over HDMI rather than USB or AES.

 

[DaaDaa]

MiniDSP has entered the ring with their HT, HTx and Tide16, though with the caveat of having to send audio over HDMI rather than USB or AES.

Weird choice to go with hdmi over usb and aes.

 

[ZeDestructor]

Weird choice to go with hdmi over usb and aes.

Not that weird when you factor that the typical user of such would be on Windows where the only real way to get >7.1 is to bitstream the audio track directly to the AVR/AVP over HDMI.

 

[fabriceo]

Weird choice to go with hdmi over usb and aes.

if you implement long elastic buffer and extremely clean PLL then the HDMI transport "might" be OK ish.
Still the DAC needs to resample with an ASRC or DPLL if you want it to be clocked by a clean local crysteck for example.
Remember CD players in the 80's , they were all delivering bad sound despite "digital precision", until every one understood the importance of clock and jitter.
USB came in with beautiful Async possibility, and streamer were preferred to CDs...

so I hope they did their homework to implement hdmi correctly (with a fast fpga) in their 16 channels device.

 

[ZeDestructor]

if you implement long elastic buffer and extremely clean PLL then the HDMI transport "might" be OK ish.
Still the DAC needs to resample with an ASRC or DPLL if you want it to be clocked by a clean local crysteck for example.
Remember CD players in the 80's , they were all delivering bad sound despite "digital precision", until every one understood the importance of clock and jitter.
USB came in with beautiful Async possibility, and streamer were preferred to CDs...

so I hope they did their homework to implement hdmi correctly (with a fast fpga) in their 16 channels device.

They have published some of their AP measurements and so far, so good (though nothing on Jitter.. though being 2026 and miniDSP, I would not be worried about such basic deficiencies). Would be nice to see the full results and external validation of their claims though.

 

[Kal Rubinson]

exaSound does not have aes inputs. So not easily compatible for 4k blu rays. Nor Trinnov. Merging Hapi has been tested? What is the SINAD?

Figure it out. https://www.stereophile.com/content/merging-hapi-mkii-multichannel-digital-processor-measurements

 

[dziemian]

Wow. $8000 for a 16 channel dac? Audient Oria seems to be a more resonable choice.

 

[Extreme_Boky]

My Dac8 Pro broke after 6 years. Along with a few other devices. No fault of Okto. My electric company. They came down & fixed.

Dac8 won't power up. The Dac8 nor my Wifi equipment.
My Benchmark AHB's had some sotra protection & shut it self down. Too bad Dac8 has no protection.

I cannot find any other 8 channel DAC that has AES and that was measured, so ordered another one. I use it with the Vanity -> Trinnov Demon-> Dac8. Hurts buying same tech 6 years later. I normally replace things that are that old. LOL

I am hoping 2 things got fixed since my last purchase. Someone said the channels were not synced perfect? Has this been addressed? What about the bit depth screen for AES?

I figured out how I can use the Oppo to get the bit depth limited for it plays physical media. If I hold down the info button it gives the audio bit rate. But it depends on the channel count on what to expect. For DTS-HD Master Audio 5.1 will be 3-5mb for 24-bit. And 1-2mb for 16. Would be nice to see it without clicking buttons. Dolby Atmos seams to always be 16-bit. So in terms of bit-depth I guess we went backwards.

Okto uses a readily available mains transformer from Talema. I am not sure if your DAC model uses an IEC RF filter... if it does, the in-built fuse could be blown??

The whole power supply section seems very straightforward as well, with TO220 "simple" (cheap) voltage regs. Maybe lift the lid and check if you are getting those +15, -15 and +5V DC voltage rails..??

Getting a new DAC seems a bit drastic...

... unless your household suffered a lightning strike... those are really bad because they damage everything/everywhere/all at once... in which case a new DAC is a great move.

 

[Kal Rubinson]

Wow. $8000 for a 16 channel dac? Audient Oria seems to be a more resonable choice.

The Oria is a good value for what it is but they are not really comparable.

 

[Dacapalooza]

Figure it out. https://www.stereophile.com/content/merging-hapi-mkii-multichannel-digital-processor-measurements

Wow what a cool website. Thanks! I would not have thought a stereo enthusiast place would care about multichannel. Extra points for not mentioning jet-black backgrounds or anything like that. There is way to figure out the SINAD based on the supplied data? I doubt even for $8K it would match the DAC8. But that is just a hunch.

And Google failed me. I always google multichannel DAC reviews and it never found that one. Even google is not a fan of multichannel DAC's . Or it could just be that site does not have SEO tools.

 

[Dacapalooza]

Getting a new DAC seems a bit drastic.

It did not occur to me it was fixable. It actually broke a few months ago. I should have whined then. To the one forum that would be sympathetic even if it was not fixable. I do love this forum. I love the vibe. I should hang out here more often.

Just not sure if I should deal with selling it. I am not money rich and I could use the $ even if I sold it at a loss. I do have 5 kids...

They are obviously not making many dedicated multichannel DAC's. People are obviously not buying them. I am concerned Okto will stop making them. Also maybe one day a pre pro will beat a dedicated multichannel DAC. I imagine not much research is going into dedicated multichannel DAC's. But even if one did would it have the right room correction? Trinnov I can watch movies/listen to music for hours. Dirac maybe 2 movies. In fact I am concerned that maybe my Trinnov is somehow removing too much bass. I just got the perlisten sub that I nickednamed big mama. Still I can watch for hours straight.

My current system retails for $50K. Every single gear I have was once measured as the least distortion ever at one point in time in recent years. By the tester anyway. So it would be shame that if just my DAC did not match distortion wise.

 

[Dacapalooza]

There is way to figure out the SINAD based on the supplied data?

Speaking of SINAD-ifying things. Can we SINAD-ify speaker measurements? Are speaker equivalent of SINAD's worse than DAC's? AMP's? Pre Pros? Would that not be funny if the best speaker distortion measurements are worse than the worse Pre Pro?

 

[staticV3]

Speaking of SINAD-ifying things. Can we SINAD-ify speaker measurements?

Please don't. A single "performance metric" would be even more reductive and misleading than SINAD already is for electronics.

See e.g. the Sean Olive/Todd Welti Loudspeaker Preference score.

Are speaker equivalent of SINAD's worse than DAC's? AMP's? Pre Pros? Would that not be funny if the best speaker disortion measuresment are worse than the worse Pre Pro?

Amir posts speaker "SINAD" in every review:


You can convert Percent to dB here: https://sengpielaudio.com/calculator-thd.htm

And SINAD is just the resulting dB number times -1.

Or you can look at the absolute SPL data:


The distance in dB between Fundamental and THD at any given frequency is "SINAD".

 

[mdsimon2]

Wow what a cool website. Thanks! I would not have thought a stereo enthusiast place would care about multichannel. Extra points for not mentioning jet-black backgrounds or anything like that. There is way to figure out the SINAD based on the supplied data? I doubt even for $8K it would match the DAC8. But that is just a hunch.

And Google failed me. I always google multichannel DAC reviews and it never found that one. Even google is not a fan of multichannel DAC's . Or it could just be that site does not have SEO tools.

If you want to compare apples-to-apples, here are the Okto dac8 PRO measurements from Stereophile -> https://stereophile.com/content/okto-research-dac8-pro-da-processor-measurements.

In terms of noise and distortion performance, they are pretty similar.

Hapi looks to have slightly better dynamic range (look at -90 dBFS FFT) but also has a higher output level (6.55 V vs 4.24 V), which should provide a slight advantage (3-4 dB), although it also looks like the Hapi beats the Okto by a bit more than that (5-6 dB) which implies it has lower residual noise.

For distortion we don't have an exact comparison because Hapi used 1 kHz in to 200 kOhm (fig 12) and Okto used 50 Hz in 200 kOhm (fig 3). Again, Hapi may be a bit better here but both show objectively very low harmonics.

Michael

 

[Dacapalooza]

Please don't. A single "performance metric" would be even more reductive and misleading than SINAD already is for electronics.

See e.g. the Sean Olive/Todd Welti Loudspeaker Preference score.


Amir posts speaker "SINAD" in every review:
View attachment 527042

You can convert Percent to dB here: https://sengpielaudio.com/calculator-thd.htm

And SINAD is just the resulting dB number times -1.

Or you can look at the absolute SPL data:
View attachment 527043

The distance in dB between Fundamental and THD at any given frequency is "SINAD".

I was asking a question. So answer is no. One should not SINAD-ify speaker. If I understood your reply, One cannot because:

..most are still measuring a loudspeaker's non-linear distortion as if it was an amplifier. This is in my opinion [is] wrong...

But if one insists measuring a loudspeaker's non-linear distortion as if it was an amplifier, the SINAD in some frequencies are 50db for good speaker which is worse than the worse Pre Pro if I did the calc correct, but I am not 100% sure...

 

[Kal Rubinson]

Wow what a cool website. Thanks! I would not have thought a stereo enthusiast place would care about multichannel.

Thanks.

Please don't. A single "performance metric" would be even more reductive and misleading than SINAD already is for electronics.

Definitely.

In terms of noise and distortion performance, they are pretty similar.

And, of course, they are not audibly different although the feature sets differ.

But if one insists measuring a loudspeaker's non-linear distortion as if it was an amplifier, the SINAD in some frequencies are 50db for good speaker which is worse than the worse Pre Pro if I did the calc correct, but I am not 100% sure...

One can question the effective significance of "a loudspeaker's non-linear distortion" compared to other parameters.