• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Review and Measurements of Okto DAC8 8Ch DAC & Amp

ernestcarl

Major Contributor
Joined
Sep 4, 2019
Messages
3,106
Likes
2,313
Location
Canada
I've been doing some searching and reading on the DAC8 Pro and I understand that the DAC8 Pro DSP version was discontinued due to an inability to procure more miniSHARC units? It appears however that the miniSHARC is now available from the miniDSP website.

I wonder therefore if more DAC8 Pro DSP units will be produced if the miniSHARCs are now available again?

Something with DSP for crossovers and EQ correction in-built/native to the unit would definitely be of more interest to me. Hopefully in the future...
 

Kennyknetter

Member
Joined
Oct 5, 2019
Messages
32
Likes
89
I've been doing some searching and reading on the DAC8 Pro and I understand that the DAC8 Pro DSP version was discontinued due to an inability to procure more miniSHARC units? It appears however that the miniSHARC is now available from the miniDSP website.

I wonder therefore if more DAC8 Pro DSP units will be produced if the miniSHARCs are now available again?
Something with DSP for crossovers and EQ correction in-built/native to the unit would definitely be of more interest to me. Hopefully in the future...
Okto has hinted on such a unit in the future, but have also announced that they now prefer to stay silent until the eventual unit is ready, rather than try to set a release date as early as possible. If you have a computer as your source, you can use that as you DSP instead, with great results.
 

josh358

Senior Member
Joined
Jun 13, 2017
Messages
493
Likes
387
True, though that would mean less flexibility for the DAC as if I were to use a different source I may not have a DSP.
You can get some amazingly powerful software for the computer, though -- Acourate, Audiolense, etc.
 

Ozymandias

Member
Joined
Jun 27, 2019
Messages
23
Likes
11
True, though that would mean less flexibility for the DAC as if I were to use a different source I may not have a DSP.
Based on my understanding of the manual (I’ve pasted the key sections below) if you use USB/AES input mode of the DAC8 Pro you could still use DSP.

On Mac OS and Linux, no driver is needed thanks to the USB Audio Class 2.0 standard used by the unit, and the DAC8 PRO will be recognized as an 8-channel playback device and an 8-channel recording device.

USB / AES is a unique mode of operation that does use the master clock recovered from the 1st AES/EBU to set the pace of the audio data transfer from the USB host. This means that the data recovered by the AES/EBU inputs are transported in a bit-perfect manner to a USB host via the 8 USB input channels, allowing them to be recorded or processed and sent back to the USB output channels to be replayed by the DAC8 PRO.

So I think it would be possible to connect your source to the AES inputs , and a computer (with DSP processing with low enough latency ) to the usb. In USB/AES mode the signal flow would be

source => DAC8 AES/EBU input => DAC8 USB host => computer DSP => DAC8 USB host => DAC8 D/A converter => analog outs

Hopefully @Okto Research can chime in here.
 

cjf

Active Member
Joined
Apr 20, 2016
Messages
160
Likes
58
Location
CO
What no Thunderbolt3? All new DAC's should come with this interface standard IMO or at least having both USB and TB3. Seems like without TB3 you are already introducing an outdated piece of kit.
 

Kennyknetter

Member
Joined
Oct 5, 2019
Messages
32
Likes
89
Based on my understanding of the manual (I’ve pasted the key sections below) if you use USB/AES input mode of the DAC8 Pro you could still use DSP.

As far as I've understood it, the DAC8 can be considered to be a soundcard that is integral with the computer, as much as any internal soundcard would be.
 

cord4

New Member
Joined
Dec 22, 2019
Messages
4
Likes
6
Received my DAC8 PRO today! Order number in the 50s. Could someone with a DAC8 in hand please share the settings to get native DSD / DoP working through Windows 10? I have tried a number of online guides and different software programs to no avail. Benchmark's DAC3 was configured and played native DSD on my same Win 10 PC within minutes but I can't get any sound output from the Okto DAC8 in DSD (works fine in PCM). The panel indicates DSD64 DoP but there's no sound.

Pavel, maybe you could share the settings you used when testing DSD playback on a Windows PC?
 

josh358

Senior Member
Joined
Jun 13, 2017
Messages
493
Likes
387
Received my DAC8 PRO today! Order number in the 50s. Could someone with a DAC8 in hand please share the settings to get native DSD / DoP working through Windows 10? I have tried a number of online guides and different software programs to no avail. Benchmark's DAC3 was configured and played native DSD on my same Win 10 PC within minutes but I can't get any sound output from the Okto DAC8 in DSD (works fine in PCM). The panel indicates DSD64 DoP but there's no sound.

Pavel, maybe you could share the settings you used when testing DSD playback on a Windows PC?
Mine came too, also in the 50s.
 

cord4

New Member
Joined
Dec 22, 2019
Messages
4
Likes
6
Also in addition to the ASIO issue above I have a strange grounding/buzzing issue on mine if anything is plugged into outputs 5 or 7 on my DAC8 Pro. Currently everything is dead silent (when no audio is playing) with those channels having no connection (I just moved my two rear connections of my 5.1 setup, previously in ports 5 and 6, to ports 6 and 8 on my DAC8 Pro). Alas I am using unbalanced equipment (Odyssey Stratos HT-3 and Odyssey Kismet Stereo in Khartago case) and have read this thread, the manual, and various forums about hum problems with unbalanced equipment. The buzzing occurs even when the DAC8 is powered off and unplugged from the power source (everything is connected to one wall outlet).

As an update to my above note, the Benchmark DAC3 in my setup played native DSD with WASAPI output (is that supported by DAC8 Pro? It did not work with any audio in my testing with Foobar2000).

My DAC8 with Asio4all was producing garbled PCM output until I set the Asio4all option Buffer Offset to the max (20ms). You have to click DAC8Pro in the WDM device list first before adjusting the buffer offset option. Hope that helps others.
 

Okto Research

Member
Joined
Dec 4, 2018
Messages
55
Likes
588
Location
Prague
@Okto Research used to have that option on their website, but it has been removed. Maybe @Okto Research can chime in and let us know if it is still available.
Custom output voltage still available as an off-menu option. May turn into a paid extra in future.

I have noticed a very slight pop at turn on/off but it is very minimal and I am not at all concerned about it. My amplifier is not balanced though so in this case there is no guarantee to be pop free.
With balanced amplifier inputs, output pop at turn on/off should be abysmal and only related to DC offset (typically 1-2mV).

The buzzing occurs even when the DAC8 is powered off and unplugged from the power source (everything is connected to one wall outlet).
Well, this is self-answering. There is no buzzing coming from the DAC8 PRO, your amplifiers' unbalanced inputs pick up the result of equalizing ground currents that flow between themselves (through the DAC8 PRO enclosure) if you close the loop by connecting something else grounded to the additional outputs. But it seems like at least one of your amplifier models does have balanced inputs. If these are properly designed (without the "pin1 problem" that some older gear had), the issue should go away.

I must stress again that although it might work in some configurations, we strongly discourage from using the DAC8 PRO with XLR-RCA cables. Not only it makes one of the DAC8 PRO output leads shorted (by design of these cables) so the distortion skyrockets, but you also loose 1/2 of the dynamic range, some degree of EMI issues is likely to happen and additionally, pop-free turn on and off is not guaranteed.

As an update to my above note, the Benchmark DAC3 in my setup played native DSD with WASAPI output (is that supported by DAC8 Pro? It did not work with any audio in my testing with Foobar2000).

JRiver's WASAPI works with DAC8 PRO for PCM without any drivers installed, but it requires 7.1 output channels to be selected. For some reason, JRiver doesn't allow 2-channel output setting with an 8-channel DAC with WASAPI, while on the other hand, it doesn't allow other than 2-channel setting for DSD and DoP. We need to contact JRiver to ask them whether this could be fixed. Currently, we have an alternative option for DSD in JRiver that works very well. We've provided it to cord4 already, anyone else interested please e-mail us.

dac8pro_jriver_wasapi.png
Based on my understanding of the manual (I’ve pasted the key sections below) if you use USB/AES input mode of the DAC8 Pro you could still use DSP.

So I think it would be possible to connect your source to the AES inputs , and a computer (with DSP processing with low enough latency ) to the usb. In USB/AES mode the signal flow would be

source => DAC8 AES/EBU input => DAC8 USB host => computer DSP => DAC8 USB host => DAC8 D/A converter => analog outs

Hopefully @Okto Research can chime in here.

Yes, that is exactly what we had in mind when implementing the AES/EBU to USB functionality. The planned Owner's manual update is going to bring some examples of usage.

Merry Christmas to everyone! DAC8 Stereo unveiling to take place within several days. Also, one more batch of DAC8 PROs is about to ship by the end of the year.
 

pma

Major Contributor
Joined
Feb 23, 2019
Messages
4,591
Likes
10,727
Location
Prague
@Okto Research , I wonder why the floating balanced output (like in DRV134)
https://www.ti.com/lit/ds/symlink/drv134.pdf
is used so rarely. Not only it brings a notable improvement thanks to output CMR capability, but after you put one of the outputs to the ground, voltage on the second one doubles and there are no issues with XLR==>RCA adapters.
 

cord4

New Member
Joined
Dec 22, 2019
Messages
4
Likes
6
Thanks for your replies and support, Pavel. The DAC8 PRO sounds great in my setup!

Pavel, I am curious by your note "if you close the loop by connecting something else grounded to the additional outputs." What is the easiest/most cost-effective way to do that? Is it a matter of cutting open 2 old XLR cables and attaching pin 1 of each cable to the metal case of the amp? It is confusing to me that I'd need to do that while connected to DAC8 outputs 5 and 6 but not outputs 6 and 8.

I can confirm that native DSD 64 and 128 work with the driver Pavel provided me. DSD DoP still does not work in foobar2000 though I do not mind.

To hopefully save hours of time, below are my notes for getting DAC8 native DSD to work on foobar2000 (copied and modified from the DIYINHK web site). The newest foo_input_sacd and ASIOProxy do not work with native DSD.

1) After installing a fresh copy of foobar2000, use Pavel's driver

2) ONLY USE foo_input_sacd-0.8.4 of Super Audio CD Decoder plug-in for Foobar2000. Do not use later versions as native DSD doesn't seem to work.

http://sourceforge.net/projects/sacddecoder/files/foo_input_sacd/

3a) unzip and double click to install ASIOProxyInstall-x.x.x.x.exe (contained in 0.8.4 download)

3b) Foobar > Files > Perferences > Components > Install > foo_input_sacd.fb2k-component

4. Configure the output device: Foobar > Files > Preferences > Playback > Output > Device (ASIO: foo_dsd_asio)

5. Configure the ASIO output: Foobar > Files > Preferences > Playback > Output > ASIO > foo_dsd_asio(double click)

5a) ASIO Driver: set to ASIO Driver provided by Pavel

5b) DSD Playback Method: ASIO Native

6. Foobar > Files > Perferences > Tools > SACD > ASIO Driver Mode: DSD

7. click playback - output - asio. click foo_dsd_asio, click add new in the custom channel mappings area. ok to click use 64 bit asio driver checkmark. set custom channel mapping for foo_dsd_asio (in my setup L,R,C,LFE,LS,RS for outputs 1-6) and then select this mapping in Playback-output
 

ppataki

Major Contributor
Joined
Aug 7, 2019
Messages
1,216
Likes
1,356
Location
Budapest
JRiver's WASAPI works with DAC8 PRO for PCM without any drivers installed, but it requires 7.1 output channels to be selected. For some reason, JRiver doesn't allow 2-channel output setting with an 8-channel DAC with WASAPI, while on the other hand, it doesn't allow other than 2-channel setting for DSD and DoP. We need to contact JRiver to ask them whether this could be fixed. Currently, we have an alternative option for DSD in JRiver that works very well. We've provided it to cord4 already, anyone else interested please e-mail us.

View attachment 43466

@Okto Research
Please let us know once Jriver fixes this issues with WASAPI mode - I am planning to buy a DAC8 Pro but will use it in 4.0 mode hence it will be important for me too

Thank you & Merry Christmas!
 

Okto Research

Member
Joined
Dec 4, 2018
Messages
55
Likes
588
Location
Prague
After months of hard work, we are here on the very end of the year to share what we have accomplished with our new product, the DAC8 Stereo!
dac8stereo_front.jpg

Connectivity
dac8stereo_back.jpg

We received many questions about a possibility of a a second optical input, so we decided to make it a last-minute addition. The full set of DAC8 Stereo inputs now is:
  • USB
  • 2x optical (TOSLINK)
  • 2x coaxial (SPDIF)
  • 1x AES/EBU (compatible with SPDIF voltage levels)
  • Ethernet and Wi-Fi (through Raspberry Pi 4)
The unit also features a trigger output (pulsed/continuous) to turn on your amplifier. Together with the auto on&off functions of the DAC8 Stereo, you don't need to worry about powering your gear anymore, just play the music and the magic happens.

Each of the DAC8 Stereo's analog outputs is available on 2 XLR connectors, which you may find useful for connecting a powered subwoofer or a second amplifier with a separate pair of speakers.

However, you will not find an unbalanced outputs on the product. We keep staying away from those since they are prone to hum and interference pickup due to using ground conductor as a signal path. To those who already didn't do so, we highly recommend switching to balanced analog connections that will save you a lot of headaches.


Analog performance

The PRO series Sabre DAC chips have 8 analog output channels. While the vast majority of D/A converters on the market have the chip's legs connected together, turning 8 channels into 2, which are then followed by an analog I/V stages, the DAC8 Stereo features a separate high-performance analog stage for each of the 8 outputs. Thanks to this approach, not only the noise of Sabre outputs, but also the noise of each of these stages gets averaged and reduced. The other benefits include reduced output impedance (to just 50 ohms), increased drive capability and increased noise immunity.

The DAC8 Stereo's outputs only have 1.2 microvolts of residual noise, which translates to a dynamic range of almost 131dB or 21.75 bits.

At the moment, we are unable to provide an exact SINAD number since it is beyond capabilities of the Rohde & Schwarz audio analyzer we use. However, it is well over 120dB and we hope it is going to make the AudioScienceReview's pink panther very very happy!


Mechanical design
dac8stereo_detail1.jpg

As well as our other product, the 8-channel DAC8 PRO, the DAC8 Stereo comes in a solid enclosure made from AW6082 aluminium alloy. The products also share cooling with a heatsink directly mounted under the whole area of the DAC board that dissipates heat evenly to the enclosure.

Each 10mm (0.4") thick front panel starts its life as a part of a large and heavy sheet. After being laser-cut, it receives our signature, hand-made brushed finish. Then it is precisely CNC machined and anodized, while the last step is laser marking. All the production takes place locally, either in Prague or at our suppliers in nearby parts of Bohemia. The front plate is available in silver (natural anodized) or black (black anodized).

And yes, there is a new knob! In-house designed and made to fit the overall design of the product better than the off-the-shelf one we used before. Thanks to a new way of attachment, it provides a rock-solid feel without wobble.

Enjoy your End of Year celebrations!

Pavel, Okto Research
 

Attachments

  • dac8stereo_detail2.jpg
    dac8stereo_detail2.jpg
    639.2 KB · Views: 231
Last edited:

Hemi-Demon

Senior Member
Joined
Jan 17, 2019
Messages
435
Likes
514
Is a 9028Pro still the chip inside the Dac8 Stereo? Why the increase in price for less output channels?
 

Feyire

Active Member
Joined
Mar 9, 2019
Messages
272
Likes
314
Location
Netherlands
ive-been-looking-forward-to-this-when-you-needed-more-47798955__01.png


At last.
 

Panelhead

Senior Member
Forum Donor
Joined
Apr 3, 2018
Messages
348
Likes
137
What no Thunderbolt3? All new DAC's should come with this interface standard IMO or at least having both USB and TB3. Seems like without TB3 you are already introducing an outdated piece of kit.
I think you are beating a dead horse. I have two Thunderbolt interfaces. Do not know if anyone else here has one.
It is like my desire for a 20 - 25 watt version of the Benchmark AHB2. Market size of one.
I do like multi channel capability. I might buy one If the chips were configurable as 2, four,or 8 channel balanced output using a FPGA. With a single digital volume pot.The ESS attenuator function is SOTA, 32 bit.
 
Top Bottom