Review and Measurements of Okto DAC8 8Ch DAC & Amp

[Mario Sanchez]

I wonder if they fit 8 XLR & SE outputs on the back?

No, there are only TRS balanced outputs, plus a pair of 12V trigger and USB in, the unit does have internal power supply though.

 

[MCH]

Any close to 1000 eur would be a mistake no matter how it measures, the okto has plenty more features. But looks too similar to the 850 eur D90....

 

[Mario Sanchez]

Any close to 1000 eur would be a mistake no matter how it measures, the okto has plenty more features. But looks too similar to the 850 eur D90....

I *heard* that it's going to be priced a fair bit lower than the price of D90SE (which is 899USD), we'll know for sure in a few hours.

 

[Sokel]

I *heard* that it's going to be priced a fair bit lower than the price of D90SE (which is 899USD), we'll know for sure in a few hours.

For 800 euros it better be built like a tank inside and have mil spec'd components and lots of DSP,the difference will be small to the octo which is a proven value so far.

 

[Labjr]

No, there are only TRS balanced outputs, plus a pair of 12V trigger and USB in, the unit does have internal power supply though.

I prefer XLR. Especially to plastic TRS jacks. And functionality over form factor. Oh, and can the OLED display. I guess it's basically an ESS pro chip configured with 8 outputs?

 

[dualazmak]

No I'm not referring to the usual little problems,I'm referring to a windows crash for example which will make the pc-based crossover obsolete and the full force of the known (rare but still) brrrrrrrrrrrrrrrrrrr pass through the dac-crossover (essentially),specially when the attenuation is also in the same side.
I'm asking because I have know such an issue but with a normal multichannel pc card (asus) which is the same principle.
So,is there any special care taken against such (rare but more than sure over the time) event?

Even though I assume my info here in this post would not be fully satisfactory for your concern,,,
You would please look at my latest system configuration with DAC8PRO. Here, I past only one diagram from that post.

Within my upstream Windows PC, I use JRiver MC's volume control as "Master Volume Controller" for which I usually set volume/gain protection of max. 85 % (-7.5 dB) during my daily music listening sessions.

I always set the main input gain at -4 dB in software digital DSP (XO/EQ) "EKIO", and the OKTO DAC8PRO's preamp gain is always set at -4 dB.

One of the unique features of my setup is utilization of four HiFi "integrated amplifiers", i.e. each of them has its own volume/gain controller. Last week in this post, I pointed again about the pros of using "integrated amplifiers" in our active multichannel systems.

My active L&R sub-woofers also have own built-in amplifiers and volume/gain controllers.

Of course, during the procedures of Windows Update and other major OS maintenance and JRiver/EKIO upgrade, I set all of the volume/gain controllers at sound-off (minus infinity dB) positions.

Also please note that I use "EKIO" as OS-system-wide DSP (XO/EQ) center (which can be mute-off or shutdown any time if I like), and I feel this is better in terms of "safety concern" than using JRiver's (or Roon's) built-in DSP(XO/EQ) functionalities.

As you can see in my latest system setup, I have been using protection capacitors in SP high level signals going into my treasure Beryllium Squawkers, Beryllium Tweeters and metal horn Super-Tweeters.

Furthermore, all of you may agree that we should be very careful enough in our "Shutdown Sequences" and "Ignition (Start-Up) Sequences" of our multichannel setup so that we should avoid/minimize any possible pop damage to our gears including DACs, amplifiers and SP drivers. Just for your reference, therefore, you would please find my post;
- Startup (ignition) sequences and shutdown sequences of multichannel multi-amplifier system: #426

Having these self-defensive measures and careful operations, I never experienced "destructive high-gain incident" in my multichannel multi-driver multi-way multi-amplifier stereo audio system using DAC8PRO.

 

[Mario Sanchez]

I prefer XLR. Especially to plastic TRS jacks. And functionality over form factor. Oh, and can the OLED display. I guess it's basically an ESS pro chip configured with 8 outputs?

Well, I don't have anything about the menu functionality, but I'm pretty sure this is just a simple DAC w/o fancy stuff like surround codec decode and such, so you could say that this is, indeed, "just" an ESS90x8pro configured to have 8 separate outputs, but so is the Okto DAC reviewed in this thread. (the pro version of the Okto DAC has AES in, though, which might be an attraction for some wanting PC-based DSP but not playback).
As for the TRS/XLR difference...TRS connections were used on a lot of pro interfaces to save space, and I think this is the case here. I don't think Topping can stuff 8 XLRs on that rear panel even if they wanted to. I would agree, however, that XLR are sturdier than TRS connections, 1/4in TRS/TS is still generally more workable and better than friction-fit connectors like RCA in my mind.
EDIT: Someone was kind enough to inform me that Okto's using ESS9028pro and not ESS9038pro, edited to reflect that.

 

[Doodski]

Even though I assume my info here in this post would not be fully satisfactory for your concern,,,
You would please look at my latest system configuration with DAC8PRO. Here, I past only one diagram from that post.
View attachment 217839

With in my upstream Windows PC, I use JRiver MC's volume control as "Master Volume Controller" for which I usually set volume/gain protection of max. 85 % (-7.5 dB) during my daily music listening sessions.

I always set the main input gain at -4 dB in software digital DSP (XO/EQ) "EKIO", and the OCTO DAC8PRO's preamp gain is always set at -4 dB.

One of the unique features of my setup is utilization of four HiFi "integrated amplifiers", i.e. each of them has its own volume/gain controller. Last week in this post, I pointed again about the pros of using "integrated amplifiers" in our active multichannel systems.

My active L&R sub-woofers also have own built-in amplifiers and volume/gain controllers.

Of course, during the procedures of Windows Update and other major OS maintenance and JRiver/EKIO upgrade, I set all of the volume/gain controllers at sound-off (minus infinity dB) positions.

Also please note that I use "EKIO" as OS-system-wide DSP (XO/EQ) center (which can be mute-off or shutdown any time if I like), and I feel this is better in terms of "safety concern" than using JRiver's (or Roon's) built-in DSP(XO/EQ) functionalities.

As you can see in my latest system setup, I have been using protection capacitors in SP high level signals going into my treasure Beryllium Squawkers, Beryllium Tweeters and metal horn Super-Tweeters.

Furthermore, all of you may agree that we should be very careful enough in our "Shutdown Sequences" and "Ignition (Start-Up) Sequences" of our multichannel setup so that we should avoid/minimize any possible pop damage to our gears including DACs, amplifiers and SP drivers. Just for your reference, therefore, you would please find my post;
- Startup (ignition) sequences and shutdown sequences of multichannel multi-amplifier system: #426

With these self-defensive measures and careful operations, I never experienced "destructive high-gain incident" in my multichannel multi-driver multi-way multi-amplifier stereo audio system using DAC8PRO.

Your system just keeps getting better and better. It must be a lot of fun to operate and listen to.

 

[Labjr]

@dualazmak Any reason why you chose different amps? I'm not familiar with EKIO.

 

[Labjr]

Well, I don't have anything about the menu functionality, but I'm pretty sure this is just a simple DAC w/o fancy stuff like surround codec decode and such, so you could say that this is, indeed, "just" an ESS9038pro configured to have 8 separate outputs, but so is the Okto DAC reviewed in this thread. (the pro version of the Okto DAC has AES in, though, which might be an attraction for some wanting PC-based DSP but not playback).
As for the TRS/XLR difference...TRS connections were used on a lot of pro interfaces to save space, and I think this is the case here. I don't think Topping can stuff 8 XLRs on that rear panel even if they wanted to. I would agree, however, that XLR are sturdier than TRS connections, 1/4in TRS/TS is still generally more workable and better than friction-fit connectors like RCA in my mind.

I've pondered over building Linkwitz LX521.4 and using an Analog vs DSP crossover. Not sure there's currently any affordable DSP which will exceed the performance of the ASP. Now that I've been on ASR for a couple years, I'm also interested in room correction and EQ for other purposes. Would be nice to have the whole ball of wax in one piece of software or DSP box.

 

[dualazmak]

@dualazmak Any reason why you chose different amps? I'm not familiar with EKIO.

First, you would please read my post here!
- (Provisional) Decision on amplifiers selection and photos of the listening environments: #311

I actually had long and intensive "amplifier exploration" journey in my multichannel project.

You would please find here (on this my project thread) and here (remote independent thread post) the Hyperlink Index of my project thread and some of my related posts in remote threads.

 

[dualazmak]

Hello @Labjr,

As for your point on amplifier selection in multichannel systems, my post here and here would be also of your interest...

 

[lewdish]

Given the new DM7 I hope eventually companies like Topping and SMSL get into the AVR game~

 

[Labjr]

Given the new DM7 I hope eventually companies like Topping and SMSL get into the AVR game~

Or surround sound processor game.

 

[wineds]

Or electric dog polisher game.

 

[wisechoice]

I have meridian hd621 and dac8pro.
I use spdif meridian output to an spdif to xlr adapter to the dac8pro.
I have a dropout every 5-10 second or so. So it is not usable.
So I assume the spdif signal level of the meridian is not enough for the dac8pro AES input.
The meridian spdif output to another dac with an spdif input does not have dropout.

FYI, I was able to get a second hand HD621 working with S/PDIF out to the Dac8 Pro with a combination of adapter + cables of different lengths:

10' XLR male to RCA for Ch1-2
1.5ft digital audio RCA + Amazon XLR male to RCA adapter for Ch3-4
5' XLR male to RCA for Ch5-6

I thought that I was SOL with the HD621 until I tried swapping for different cables. It's possible that using all short RCA digital audio cables would work as well with an RCA to XLR adapter, but I only had one.

Other combinations worked with a direct HDMI source, but I needed a splitter for 4K (possibly because my HD621 has older firmware and I can't find the latest anywhere.) With the splitter, only the combination above worked reliably. Other arrangements consistently produced digital artifacts (pops and crackling) in one of the channel pairs.

My guess is that HDMI introduces jitter, the HDMI splitter makes it even worse, and after a certain amount of signal loss, either the HD621 or the Okto can't recover a bit perfect signal, producing dropouts and/or artifacts. So different cables at the final hop might give you better results. For that matter, a different HDMI cable might, as well.

 

[wisechoice]

FYI, I was able to get a second hand HD621 working with S/PDIF out to the Dac8 Pro with a combination of adapter + cables of different lengths:

10' XLR male to RCA for Ch1-2
1.5ft digital audio RCA + Amazon XLR male to RCA adapter for Ch3-4
5' XLR male to RCA for Ch5-6

I thought that I was SOL with the HD621 until I tried swapping for different cables. It's possible that using all short RCA digital audio cables would work as well with an RCA to XLR adapter, but I only had one.

Other combinations worked with a direct HDMI source, but I needed a splitter for 4K (possibly because my HD621 has older firmware and I can't find the latest anywhere.) With the splitter, only the combination above worked reliably. Other arrangements consistently produced digital artifacts (pops and crackling) in one of the channel pairs.

My guess is that HDMI introduces jitter, the HDMI splitter makes it even worse, and after a certain amount of signal loss, either the HD621 or the Okto can't recover a bit perfect signal, producing dropouts and/or artifacts. So different cables at the final hop might give you better results. For that matter, a different HDMI cable might, as well.

Oh, and I also had to disable upsampling to 96k on the Meridian, fwiw.

[EDIT: and disabled MMHR, as well -- thanks to @Kal Rubinson for the suggestion to try the HD 621 btw]

 

[mdsimon2]

FYI, I was able to get a second hand HD621 working with S/PDIF out to the Dac8 Pro with a combination of adapter + cables of different lengths:

10' XLR male to RCA for Ch1-2
1.5ft digital audio RCA + Amazon XLR male to RCA adapter for Ch3-4
5' XLR male to RCA for Ch5-6

I thought that I was SOL with the HD621 until I tried swapping for different cables. It's possible that using all short RCA digital audio cables would work as well with an RCA to XLR adapter, but I only had one.

Other combinations worked with a direct HDMI source, but I needed a splitter for 4K (possibly because my HD621 has older firmware and I can't find the latest anywhere.) With the splitter, only the combination above worked reliably. Other arrangements consistently produced digital artifacts (pops and crackling) in one of the channel pairs.

My guess is that HDMI introduces jitter, the HDMI splitter makes it even worse, and after a certain amount of signal loss, either the HD621 or the Okto can't recover a bit perfect signal, producing dropouts and/or artifacts. So different cables at the final hop might give you better results. For that matter, a different HDMI cable might, as well.

Very interesting, thank you for sharing. What cables did you try initially that gave you drop outs?

Michael

 

[wisechoice]

Very interesting, thank you for sharing. What cables did you try initially that gave you drop outs?

Michael

A bunch of different cables, including the the ones I listed but in a different configuration (e.g. 2x5’ and 2x10’ at various outputs).

I was almost always able to get Ch1-2 and Ch3-4 working without issue by themselves. The problems would start when 3 or more spdif outputs were in use, but the vexing thing was that known good cables would produce the problem on some outputs and not others. And that introducing the splitter would produce unpredictable but repeatable error much further downstream.

I started with just some old stereo RCA cables and the XLR adapters, which worked fine for the first two outputs. It was weird, because I had been using those cables to feed 4 separate DACs without issue before (from a Blackmagic SDI to Audio converter). One of them was longer than the other. I also had issues with the BM converter plus Okto, but managed to get it working as well, in the end.

From what I understand, digital and analog audio cables have different impedances and so do SPDIF vs AES (I think). And cable length but also device sensitivity on the receiving end can make a difference in whether analog cables and passive converters will work to carry a clear signal between them. So some devices may work with certain cables while others won’t. Interference generated from the Meridian or other equipment or cables could have also been a factor. The SPDIF signal is unbalanced, so no CMR.

 

[mdsimon2]

A bunch of different cables, including the the ones I listed but in a different configuration (e.g. 2x5’ and 2x10’ at various outputs).

I was almost always able to get Ch1-2 and Ch3-4 working without issue by themselves. The problems would start when 3 or more spdif outputs were in use, but the vexing thing was that known good cables would produce the problem on some outputs and not others. And that introducing the splitter would produce unpredictable but repeatable error much further downstream.

I started with just some old stereo RCA cables and the XLR adapters, which worked fine for the first two outputs. It was weird, because I had been using the cables to feed 4 separate DACs without issue before (from a Blackmagic SDI to Audio converter). One of them was longer than the other. I also had issues with the BM converter plus Okto, but managed to get it working as well, in the end.

From what I understand, digital and analog audio cables have different impedances and so do SPDIF vs AES (I think). And cable length but also device sensitivity on the receiving end can make a difference in whether analog cables and passive converters will work to carry a clear signal between them. So some devices may work with certain cables while others won’t. Interference generated from the Meridian or other equipment or cables could have also been a factor. The SPDIF signal is unbalanced, so no CMR.

The reason I ask is I had a very similar experience when using a miniDSP nanoDIGI with the Okto, 6 channels were OK but 8 would not work. I tried many different RCA to XLR cables as well as RCA to BNC cables in to SPDIF to AES transformers but could never get it to work with all 8 channels. Others had used the nanoDIGI with the Okto successfully in the past but had since upgraded the Okto firmware and were seeing the same issues as me. There is more discussion here -> https://www.audiosciencereview.com/forum/index.php?threads/okto-8-owner’s-thread.13899/post-684285.

I've also heard of issues with the Audiopraise VanityPro requiring an Okto firwmare upgrade but apparently the solution is very hush-hush -> https://www.audiosciencereview.com/...eview-hdmi-audio-extractor.30440/post-1240789.

I guess I was just surprised that you had issues but were able to get it to work with such an inconsistent selection of cables, although re-reading your post it seems like you are only using 6 channels which was the max I could get with the nanoDIGI.

Michael