Review and Measurements of Okto DAC8 8Ch DAC & Amp

[Tachyon88]

I switched to linux mint 22 and I downloaded jriver and I'm not sure what settings to change in order to send all my audio through jriver. None have worked so far. Is that jriver function only possible on windows ? When I play a pc game I can not hear center diogloue or it is very low volume. All I want with movies and games is to send the center (and rear I guess) to stereo. I have 2.1 right now and I tried to map all channels to 1 on the dac itself like I did with the subwoofer in order to hear it, but no dice.

 

[StianG]

Hi all,

I recently bought a Okto dac 8 dsp second hand to use as dac and crossover for my L/R channels (spdif out from a trinnov altitude 16). When I hooked it up for the first time yesterday something strange happened. The two displays are mirrored, and it is not possible to access the menus. After a night without power connected the displays looked normal, and I could control volume etc. Then I powered down and moved it to the rack, and the same thing happened. I have reached out to Okto research, but since I am impatient I thought it wouldn't t hurt to ask if anybody here has experienced the same and know the remedy? Is there a reset procedure?

 

[Tom C]

I switched to linux mint 22 and I downloaded jriver and I'm not sure what settings to change in order to send all my audio through jriver. None have worked so far. Is that jriver function only possible on windows ? When I play a pc game I can not hear center diogloue or it is very low volume. All I want with movies and games is to send the center (and rear I guess) to stereo. I have 2.1 right now and I tried to map all channels to 1 on the dac itself like I did with the subwoofer in order to hear it, but no dice.

AFAIK, that is a windows only function. The WDM drivers required for that functionality are part of the JRiver software, and are specifically for Windows.

 

[DWPress]

Is there a reset procedure?

The Okto website has instructions for firmware updates. I'd try that to see if things return to normal - Pavil and Fabricio have both indicated that if the fw is not flashed successfully it will return to the firmware originally issued with it so little chance of screwing it up further if indeed there is something wrong.

 

[StianG]

Thanks for the suggestion, but this is the dac 8 dsp with the built in minidsp nanosharc board. I cannot find any FW update for that model.

 

[DWPress]

Best to wait and hear back from Okto then. Those early units had different hardware in them subcontracted from Minidsp, not sure if the newer firmwares are even applicable.

 

[dualazmak]

I received an important big news from OKTO Research today, "OKTO Reseach Autumn 2024 Newsletter".

In response to my and our intensive requests (I believe so), OKTO is announcing support for parallel operation of DAC8PRO (demonstration of three DAC8PRO), combined into a single USB device!

They said; "This setup delivers 24 channels of audio, supporting up to 192kHz/32-bit resolution. The clocks are synchronized via AES/EBU, ensuring zero clock drift and phase shift, while volume control is unified across all units and fully managed from the master DAC. This feature opens up many possibilities for home cinema and multichannel audio setups and will be included in the upcoming firmware release."

Since it looks the detailed information is still not yet available on OKTO's web site, I dare not to copy paste all of the contents of the Newsletter here in my post on this thread (including the diagram screen shot of the coming aggregate/combined device settings for three of DAC8PRO where the first DAC8PRO serves as master clock via AES/EBU enabling 24-Ch ins and 24-Ch outs).

 

[AudioJester]

In 10 plus years of running active multi-channel speakers with PC as source - had my first full volume incident. Genelecs, so speaker protection etc., plus very short duration - no damage done other than scaring the hell out of me and the dog!

So I tries the AES/EBU output from my Okto (some claim audible benefit of digital over analogue inputs on Genelec). Took it for granted the Okto would attenuate and did not adjust volume on Roon or GLM. Well the front volume control on the Okto does nothing for the AES/EBU output - which is not what I read. Is there some secret setting? I have latest firmware.

 

[dualazmak]

So I tries the AES/EBU output from my Okto (some claim audible benefit of digital over analogue inputs on Genelec).

Do you mean the AES/EBU digital out of OKTO DAC8PRO?

If so, it is just a simple "through out" of Ch1+Ch2 digital-in which is not (and should not be) under DAC8PRO's volume/gain control by the front volume dial, but the AES/EBU digital out contains sync clock signal given by DAC8PRO for the receiving DAC gear.

I have tested the in-sync connection of this AES/EBU digital out (Ch1+Ch2) into second DAC gear (in my case I used ONKYO DAC-1000) (ref. here) confirming full synchronization, and also pointed that it is not under the volume/gain controller of DAC8PRO at that time (with my firmware ver.1.32).

 

[mdsimon2]

In 10 plus years of running active multi-channel speakers with PC as source - had my first full volume incident. Genelecs, so speaker protection etc., plus very short duration - no damage done other than scaring the hell out of me and the dog!

So I tries the AES/EBU output from my Okto (some claim audible benefit of digital over analogue inputs on Genelec). Took it for granted the Okto would attenuate and did not adjust volume on Roon or GLM. Well the front volume control on the Okto does nothing for the AES/EBU output - which is not what I read. Is there some secret setting? I have latest firmware.

Hmm...maybe they reverted the behavior for FW 1.6? They didn't update the manual for 1.6 so it would be very disappointing if that was the case.

Michael

 

[mkt]

I received an important big news from OKTO Research today, "OKTO Reseach Autumn 2024 Newsletter".

In response to my and our intensive requests (I believe so), OKTO is announcing support for parallel operation of DAC8PRO (demonstration of three DAC8PRO), combined into a single USB device!

They said; "This setup delivers 24 channels of audio, supporting up to 192kHz/32-bit resolution. The clocks are synchronized via AES/EBU, ensuring zero clock drift and phase shift, while volume control is unified across all units and fully managed from the master DAC. This feature opens up many possibilities for home cinema and multichannel audio setups and will be included in the upcoming firmware release."

Since it looks the detailed information is still not yet available on OKTO's web site, I dare not to copy paste all of the contents of the Newsletter here in my post on this thread (including the diagram screen shot of the coming aggregate/combined device settings for three of DAC8PRO where the first DAC8PRO serves as master clock via AES/EBU enabling 24-Ch ins and 24-Ch outs).

The screenshot in the email looks like a Mac aggregate device. I combine my DAC8PRO with a Focusrite 4i4 to get 12 channels (7.1.4), Maybe there is something fancier going on with the clock etc.

 

[dualazmak]

The screenshot in the email looks like a Mac aggregate device. I combine my DAC8PRO with a Focusrite 4i4 to get 12 channels (7.1.4), Maybe there is something fancier going on with the clock etc.
View attachment 402125

Yes, I agree with you, as I recently also discussed these aspects in my post #519 on the "Okto 8 Owner’s Thread" together with reference to @mdsimon2's kind post on my project thread.

I assume and hope Pavel of OKTO is now intensively working on the final test runs on multiple DAC8PROs' sync-aggregation using AES/EBU digital out (containing sync signals) into second (and third) DAC8PRO's AES/EBU input, and also the coming new ASIO driver should recognize multiple output destinations of aggregated DAC8PROs, i.e. 16 or 24 channels, through two or three USB 2.0 cables into all the DAC8PROs just like RME's multiple Fireface DAC/ADC aggregation (ref. my post here #842 on my project thread); these should work on Windows, MacOS and Linux, I hope, especially on Windows 11 which I use with JRiver and DSP EKIO.

According to Pavel's old comment here dated July 7 of 2020, it looks he prefers AES/EBU synchronization rather than outer word-clocking synchronization.

 

[dualazmak]

In 10 plus years of running active multi-channel speakers with PC as source - had my first full volume incident. Genelecs, so speaker protection etc., plus very short duration - no damage done other than scaring the hell out of me and the dog!

Do you mean the AES/EBU digital out of OKTO DAC8PRO?
View attachment 402070
If so, it is just a simple "through out" of Ch1+Ch2 digital-in which is not (and should not be) under DAC8PRO's analog-level volume/gain control by the front volume dial, but the AES/EBU digital out contains sync clock signal given by DAC8PRO for the receiving DAC gear.

I have tested the in-sync connection of this AES/EBU digital out (Ch1+Ch2) into second DAC gear (in my case I used ONKYO DAC-1000) (ref. here) confirming full synchronization, and also pointed that it is not under the volume/gain controller of DAC8PRO at that time (with my firmware ver.1.32).

And, by the way, you may agree with me that we, members of the league of multichannel multi-amplifiers audio system, should be much carful about "startup/ignition sequences" and "shutdown sequences" (especially when we change our gears and/or signal routing), as I shared my latest practices at the bottom of my lengthy post here #931 on my project thread;

Spoiler: My "startup/ignition sequences" and "shutdown sequences"

At the bottom of my lengthy post here #931 on my project thread, I wrote as follows;

The latest "startup/ignition sequences" and "shutdown sequences" as of June 26, 2024
Having the latest system configuration as of June 26 in 2024 shared above, I also would like to update my post #776 dated August 7 2023 on “Startup/Ignition Sequences” and “Shutdown Sequencies”.

A few of my dear ASR friends have contacted me asking about standard startup/ignition sequences and shutdown sequences in the multichannel multi-amplifier system together with JRiver MC (or Roon) and software crossover EKIO running on Windows 11 PC.

They were a little bit concerned about the maximum protection of speaker drivers from possible unexpected accidental pop damage, and I fully understand their worries even though I have the protection capacitors for midrange Beryllium-dome-squawkers (MDs), Beryllium-dome-tweeters (TWs) and metal-horn-super-tweeters (STs).

Although I daily perform these very familiar (to me) sequences almost unconsciously, I believe it would be worthwhile sharing the sequences with all of you visiting this thread.

Standard "Startup/Ignition Sequences":
01. Wake-up the AC Circuit Breaker (100V/15A if it has been shut-down)
02. Power-on the root switch of 24-port AC power strip (series of four 6-port strips)
______This automatically wakes up DIY-12-VU-Meter-Array, KORG DS-CAC-10, BEHRINGER DS2800
03. Power-on YAMAHA A-S3000 after making sure the volume is at -infinity dB (no sound)
04. Power-on ACCUPHASE E-460 after making sure the volume is at -infinity dB (no sound)
05. Power-on SONY TA-A1ES after making sure the volume is at -infinity dB (no sound)
06. Power-on YAMAHA A-S301 after making sure the volume is at -infinity dB (no sound)
07. Power-on L&R sub-woofers YAMAHA YST-SW1000 by remote controller (preset volume 13:00 O'clock, 1 p.m.)
08. Power-on OKTO DAC8PRO; make sure the volume (master gain) is less than -75 dB
09. Power-on Windows 11 Pro PC
10. Check & confirm wake-up and running of VB-AUDIO MATRIX at taskbar
11. Check & confirm wake-up and ready of DIYINHK ASIO at taskbar
12. Check & confirm all the Window's sound I/O (KERNEL, WASAPI, WMD, Mic, etc.) are muted-off
13. Launch DSP EKIO having default preset configuration
14. Launch JRiver MC (or Roon); make sure the master volume is at about 5 % (-77.5 dB)
15. Properly layout VB-AUDIO MATRIX, its Routing Grid view, JRiver MC32 and EKIO’s I/O Panel on PC monitor screen so that all the peak bar-meters can be seen/monitored (as shown in Fig.15)
16. Start playing JRiver e.g. the 6th track of my music sampler/reference playlist (piano solo)
17. Slightly volume-up JRiver to around 10 % (-55.0 dB); check the JRiver's small VU-EQ meter is properly dancing
18. Start “playing” EKIO
19. Check and confirm that all the EKIO's I/O VU meter bars and all the VB-AUDIO MATRIX Routing Grid VU meter bars are properly moving in exceptionally low gain
20. Volume-up A-S3000 to 11:55 o'clock (-18 dB)
21. Volume-up E-460 to -19.0 dB
22. Volume-up TA-A1ES to -17.0 dB
23. Volume-up A-S301 to 09:45 o'clock (ca. -19 dB)
24. Volume-up DAC8PRO to -4 dB; check to properly hear the sound in small volume
25. Carefully and slowly volume-up JRiver MC (as master volume) to usual listening volume using mouse wheel or COOIDEA USB volume controller

Standard "Shutdown Sequences":
01. Stop playing JRiver MC
02. Volume-down the "Master Volume" of JRiver MC to less than 5% (-77.5 dB)
03. Stop playing DSP EKIO
04. Volume-down OKTO DAC8PRO to -99 dB
05. Volume-down YAMAHA A-S301 to -infinity dB (no sound)
06. Volume-down SONY TA-A1ES to -infinity dB (no sound)
07. Volume-down ACCUPHASE E-460 to -infinity dB (no sound)
08. Volume-down YAMAHA A-S3000 to -infinity dB (no sound)
09. Power-off A-S301
10. Power-off TA-A1ES
11. Power-off E-460
12. Power-off A-S3000
13. Power-off L and R active sub-woofers YAMAHA YST-SW1000 by remote controller
14. Exit/Shutdown JRiver MC
15. Exit/Shutdown EKIO
16. Shutdown VB-AUDIO MATRIX
17. Shutdown Windows 11 Pro PC
18. Soft-shutdown (Mute-off) OKTO DAC8PRO by remote controller
19. Switch-off the root switch of 24-port AC power strip (series of four 6-port strips)
______This automatically shutdowns DIY-12-VU-Meter-Array, KORG DS-CAC-10, BEHRINGER DS2800
20. Down the AC Circuit Breaker (100V/15 A, if needed for prolonged shutdown; longer than a week or so)

Although these sequences may look somewhat complicated at your first glance, I usually complete the startup/ignition sequences in less than 3 minutes, and I complete the shutdown sequences in less than 1 minute. I believe you can agree with me that triggered simultaneous startup/power-on with pre-fixed audible gain/volume levels should be definitely avoided at least in my multichannel multi-amplifier audio setup.

 

[poopy]

Hmm...maybe they reverted the behavior for FW 1.6? They didn't update the manual for 1.6 so it would be very disappointing if that was the case.

Michael

Well, looks like I did well not to update to the latest firmware. I’ve been using the aes/ebu outputs for my active speakers for some time with same master volume control.
Specified as such on pp.10 of the user guide. It hasn’t been updated after the release of FW1.6.

 

[dualazmak]

I’ve been using the aes/ebu outputs for my active speakers for some time with same volume control.

May I ask your firmware version number when you tested such AES/EBU digital output under the volume control?

 

[poopy]

May I ask your firmware version number when you tested such AES/EBU digital output under the volume control?

FW 1.5

 

[poopy]

FW 1.5 - I have been using the master volume control for about a year now. Works petfectly. Won’t update to FW 1.6 if this has been removed.

 

[mdsimon2]

In 10 plus years of running active multi-channel speakers with PC as source - had my first full volume incident. Genelecs, so speaker protection etc., plus very short duration - no damage done other than scaring the hell out of me and the dog!

So I tries the AES/EBU output from my Okto (some claim audible benefit of digital over analogue inputs on Genelec). Took it for granted the Okto would attenuate and did not adjust volume on Roon or GLM. Well the front volume control on the Okto does nothing for the AES/EBU output - which is not what I read. Is there some secret setting? I have latest firmware.

I explored this a bit more today and at least on V1.61 DSP firmware it works as expected, the AES output is attenuated by the front knob volume control in PureAES, PureUSB and USB/AES modes. I also tried with my DSP program engaged in PureAES mode and that also worked fine. For reference here is the output of "xmosusb --dacstatus".

michael4@raspberrypi4:~ $ sudo xmosusb --dacstatus

This utility is using libusb v1.0.26.11724


[0] > VID 152A, PID 88C4, BCD 0161 : OKTO RESEARCH  DAC8PRODSP7  000096
      (0)  usb Audio Control
      (1)  usb Audio Streaming
      (2)  usb Audio Streaming
      (3)  usb DFU


printing dac status:
usb vendor ID       = 0x152A
usb product ID      = 0x88C4
xmos BCD version    = 1.61 DSP enabled
front panel version = 161
front panel status  = -5 Device running ok
maximum frequency   = 192000hz

DAC mode            = 0xB PureAES + DSP
I2S Audio config    = 0xA1 48000hz, PCM, 24b
USB Audio config    = 0xC1 48000hz, PCM, 32b
Sound presence      = 0x F
trigger/sleep       = 0x 7
usb volume          = 0dB
front panel volume  = -49dB

maximum DSP tasks   = 7
DSP program number  = 1
decimation factor   = 1
DSP Core 1: load    = 116
DSP Core 2: load    = 299
DSP Core 3: load    = 256
DSP Core 4: load    = 339
DSP Core 5: load    = 299
DSP Core 6: load    = 256
DSP Core 7: load    = 352
DSP max load        = 352 / 2199 = 16%fs
Device running ok

Is anyone else out there running vanilla FW1.6 that can test the AES attenuation? @fabriceo is there any reason there would be a difference between the regular and DSP FW in regards to attenuation of the AES output?

Michael

 

[AudioJester]

I explored this a bit more today and at least on V1.61 DSP firmware it works as expected, the AES output is attenuated by the front knob volume control in PureAES, PureUSB and USB/AES modes. I also tried with my DSP program engaged in PureAES mode and that also worked fine. For reference here is the output of "xmosusb --dacstatus".

michael4@raspberrypi4:~ $ sudo xmosusb --dacstatus

This utility is using libusb v1.0.26.11724


[0] > VID 152A, PID 88C4, BCD 0161 : OKTO RESEARCH  DAC8PRODSP7  000096
      (0)  usb Audio Control
      (1)  usb Audio Streaming
      (2)  usb Audio Streaming
      (3)  usb DFU


printing dac status:
usb vendor ID       = 0x152A
usb product ID      = 0x88C4
xmos BCD version    = 1.61 DSP enabled
front panel version = 161
front panel status  = -5 Device running ok
maximum frequency   = 192000hz

DAC mode            = 0xB PureAES + DSP
I2S Audio config    = 0xA1 48000hz, PCM, 24b
USB Audio config    = 0xC1 48000hz, PCM, 32b
Sound presence      = 0x F
trigger/sleep       = 0x 7
usb volume          = 0dB
front panel volume  = -49dB

maximum DSP tasks   = 7
DSP program number  = 1
decimation factor   = 1
DSP Core 1: load    = 116
DSP Core 2: load    = 299
DSP Core 3: load    = 256
DSP Core 4: load    = 339
DSP Core 5: load    = 299
DSP Core 6: load    = 256
DSP Core 7: load    = 352
DSP max load        = 352 / 2199 = 16%fs
Device running ok

Is anyone else out there running vanilla FW1.6 that can test the AES attenuation? @fabriceo is there any reason there would be a difference between the regular and DSP FW in regards to attenuation of the AES output?

Michael

Thanks. I will try again this weekend.

 

[fabriceo]

@fabriceo is there any reason there would be a difference between the regular and DSP FW in regards to attenuation of the AES output?

Michael

Hi Guys
quick review of the V1.6 and V1.61 source code show that the knob volume is always applied on the AES output for DAC8PRO with or without DSP extension. we have planned for a possible exception for future version but this option is not yet implemented in the front panel menu.

please share any different findings