Review and Measurements of Okto DAC8 8Ch DAC & Amp

[waynel]

I am hearing some hiss from the tweeter using the DAC8, something I didn't hear from the Topping D70 which I used before. It's very faint though, I need to bring my ear within 20cm or so to hear it.

This is strange considering the low noise of both, can I ask you what amp you are using? Anything else in the the signal path? Also is your DAC8 pro the standard 4V output? anything else change in the setup?

Wayne

 

[Honken]

Thank's for the reply.
If I got you right you can change perceived volume via ALSA but the display of the DAC doesn't reflect this change right?

Correct.

My DAC8 is standard voltage indeed.

Regarding the hiss, yeah it is very weird - but also a very minor problem. I connected my old D70 again today to see if I was imagining things, but no - with it connected my speakers are dead silent. But, while fiddling around I did notice something, the hiss in my speakers persist even without any input to the amps. I am guessing this is some sort of a ground loop but I'm not sure, the electrical side of things is not my forte.

Due to the width difference between the D70 and DAC8 I had to buy new interconnects anyway. We'll see, maybe the swap will help (but I doubt it).

My setup is as follows: Raspberry 4 -> USB -> DAC8 -> XLR -> Audiophonics NC400 Monos -> Elac DBR-62. All connected to the same power strip.

I wonder about the hiss! The DAC is the best ever measured here (1) Okto dac8 stereo DAC Review | Audio Science Review (ASR) Forum. Probably the output voltage of the DAC is too high for your amplifier. Can you go up with volume to 0dB without clipping the amp? If not you should get an XLR attenuator like that Amazon.com: Hosa XLR weiblich auf XLR männlich Eingangsdämpfungsregler: Electronics between the DAC and the Amp. This will decrease the hiss and increase the resolution of the DAC.

Well, the DAC8 seems to be about as loud as the D70, but I don't know how high I can go before the NC400 clips as the combo does get stupidly loud. I do eat up some of that loudness in my DSP though (which I haven't gotten up and running at the moment so no weirdness is coming from that).

 

[ChrisPL]

Thank's for the reply.
If I got you right you can change perceived volume via ALSA but the display of the DAC doesn't reflect this change right?

When I change either master volume ( numid=5) or individual channel volume (numid=6), there is no change to the DAC8PRO volume output or the DAC8PRO volume setting display. I have firmware 1.4. Amixer accepts the requested changes

pi@raspberrypi:~ $ amixer -c3 cset numid=5 10,10,10,10,10,10,10,10
numid=5,iface=MIXER,name='DAC8PRO Playback Volume'
; type=INTEGER,access=rw---R--,values=8,min=0,max=99,step=0
: values=10,10,10,10,10,10,10,10
| dBminmax-min=-99.00dB,max=0.00dB

but the volume output of the DAC8PRO is not changed.

I tried changing what I assume are
- master mute, numid 4
- individual channel mute, numid 3

same results, no effects on the DAC8PRO. The DAC8PRO mute, volume and chanel routing settings are not reflected in the amixer.

I don't know what the numid 8 'Keep Interface' is, maybe the keep display on setting ?, regardless, I dont see any difference with it set to on.

Should we expect the amixer to display and set the volume settings of the DAC8PRO ? if so, it does not seem to be working for me with firmware version 1.4 connected to a raspberry pi with raspbian OS

Christian

 

[ChrisPL]

[QUOTEIf it can be controlled does the volume you set in roon show up on the display of the DAC meaning is it in sync with the roon setting?][/QUOTE]

The DAC volume is not "in sync" with the roon setting. If you set the device volume as "fixed" in roon, then yo have to use the DAC8PRO to control volume. If you set the device volume as "device" in roon, roon will apply the volume from its vol slider setting before sending this to the DAC which will then apply its own volume control setting that it displays.

 

[DrCWO]

Just to clarify:
ChrisPl says that making changes with the amixer there is no percivable change at the volume of the speaker nor a change in the displayed number in front of the DAC. This is opposite what Honken says!? Honken, wht firmware did you use?
If you run the roobridge on your Raspberry the I expect the device volume will have no effect. To test if the roon volume created changes inside the DAC you should connect the DAC directly with the core.

 

[ChrisPL]

When I checked roon for you, my set up was roon core on a NAS > rpi running roon bridge > DAC8PRO

FYI my regular set up is roon core on NAS with src to 96k > RPI running roon bridge > roon bridge out to RPI loopback device> loopback capture to Camilla DSP FIR crossover > Alsa 8 ch DAC8PRO

Christian

 

[dualazmak]

[QUOTEIf it can be controlled does the volume you set in roon show up on the display of the DAC meaning is it in sync with the roon setting?]

The DAC volume is not "in sync" with the roon setting. If you set the device volume as "fixed" in roon, then yo have to use the DAC8PRO to control volume. If you set the device volume as "device" in roon, roon will apply the volume from its vol slider setting before sending this to the DAC which will then apply its own volume control setting that it displays.

I agree with you. "Where and how to control master volume and relative gains" is always one of the important issues in multichannel multi-amplifier systems, including my project using JRiver (or Roon), software crossover EKIO, DAC8PRO and multiple integrated and/or power amps.

Just for all of your reference, I prepare and use my "Check Sheets" like this in my project with integrated amps;

and for power amps, like this;

As you can see, I am just using JRiver MC's (or Roon's) volume controller as "Master Volume Controller" in the entire multichannel multi-amplifier system. And, in the downstream, all of the red numeric numbers are the adjustable/controllable gains and/or volumes.

The software crossover EKIO's many gain values can be saved as "EKIO configuration file" of any file name, and also the DAC8PRO's gains are saved on "hard and soft shutdown" and they are retrieved on next power-on.

If needed, please visit my thread post #283 and thereafter for further details.

 

[ChrisPL]

I think there were some problems with the DAC8PRO firmware 1.34 with linux. I expect there are a number of changes in firmware version 1.4 that affect compatibility with linux.

 

[dualazmak]

I think there were some problems with the DAC8PRO firmware 1.34 with linux. I expect there are a number of changes in firmware version 1.4 that affect compatibility with linux.

Noted, thanks.

Fortunately(?), my DAC8PRO's firmware is ver.1.32, and I have no problem at all as far as using full USB DIYNHK ASIO input from EKIO on Windows 10 PRO 64 bit PC and digital AES/EBU (CH1+CH2 through) + analog XLR output under its gain/volume control. I never used/tried my DAC8PRO with Linux.

 

[Honken]

Just to clarify:
ChrisPl says that making changes with the amixer there is no percivable change at the volume of the speaker nor a change in the displayed number in front of the DAC. This is opposite what Honken says!? Honken, wht firmware did you use?

Mine reports firmware 1.42.

Doesn't matter too much though, if you are set on controlling it with ALSA you can always slave the card to softvol/dmix in /etc/asound.conf like so:

pcm.softvol {
    type softvol
    slave.pcm "dmix"
    control.name "PCM"
    control.card 0
}
pcm.!default {
    type plug
    slave.pcm "softvol"
}

You will get a new control from ALSA called PCM, use that to change the volume. If you wish to set the channels individually it becomes a bit more involved but it is doable as well.

Personally I'm not too bothered since I use Pulse. And yes, changing the volume works just fine there as well

 

[DrCWO]

Thank's for the hint. As far as I know softvol is different than changing volume directly in the DAC. Changing volume directly in the DAC means changing ths volume of the ESS-Chips. My believe this will be "nearly" lossless and should be far better than softvol.
Therefore my wish is to control DAC volume via ALSA and as far as I undersood until now this is not possible.

 

[ChrisPL]

I think you will maintain a 32 bit path from roon to the DAC8PRO. There should be no fidelity loss using roon volume control vs DAC8PRO volume control.

Was not aware of softvol, interesting option thanks for the tip. Having said this, controlling DAC8PRO volume directly , if possible, would be much cleaner implementation with DAC8PRO display reflecting actual volume setting.

 

[Honken]

I'll admit to not fully understanding how ALSA operates under the hood, but I'm fairly certain that dmix would be involved in the case where using alsamixer works, but the changes aren't reflected on the DAC itself. Changing the volume in software has to happen somewhere, "pure" ALSA or not.

I personally don't bother worrying about bit depth and volume changes, but if I were paranoid I'd do it in my DSP as that is running in 32bit float mode.

 

[ChrisPL]

Maybe this will be useful for those that are more familiare with ALSA than I am. I noticed the type S16 for the volume control, is volume control then limited to 16 bit ? For the playback , this confirms wha i have found DAC8PRO only accepts either S32_LE or S16_LE format. For S32_LE, not sure what the implicatiosn of the Bits=24 is.

pi@raspberrypi:/proc/asound/card3 $ cat usbmixer
USB Mixer: usb_id=0x20b12009, ctrlif=0, ctlerr=0
Card: OKTO RESEARCH DAC8PRO at usb-0000:01:00.0-1.1, high speed
Unit: 10
Control: name="DAC8PRO Playback Volume", index=1
Info: id=10, control=2, cmask=0x0, channels=1, type="S16"
Volume: min=-25344, max=0, dBmin=-9900, dBmax=0
Unit: 10
Control: name="DAC8PRO Playback Volume", index=0
Info: id=10, control=2, cmask=0xff, channels=8, type="S16"
Volume: min=-25344, max=0, dBmin=-9900, dBmax=0
Unit: 10
Control: name="DAC8PRO Playback Switch", index=1
Info: id=10, control=1, cmask=0x0, channels=1, type="INV_BOOLEAN"
Volume: min=0, max=1, dBmin=0, dBmax=0
Unit: 10
Control: name="DAC8PRO Playback Switch", index=0
Info: id=10, control=1, cmask=0xff, channels=8, type="INV_BOOLEAN"
Volume: min=0, max=1, dBmin=0, dBmax=0
Unit: 41
Control: name="OKTO RESEARCH Internal Clock Validity", index=0
Info: id=41, control=2, cmask=0x0, channels=1, type="BOOLEAN"
Volume: min=0, max=1, dBmin=0, dBmax=0

and

pi@raspberrypi:/usr/share/alsa/cards $ cat /proc/asound/card3/stream0
OKTO RESEARCH DAC8PRO at usb-0000:01:00.0-1.1, high speed : USB Audio

Playback:
Status: Stop
Interface 1
Altset 1
Format: S32_LE
Channels: 8
Endpoint: 1 OUT (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 24
Interface 1
Altset 2
Format: S16_LE
Channels: 8
Endpoint: 1 OUT (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 16
Interface 1
Altset 3
Format: SPECIAL DSD_U32_BE
Channels: 8
Endpoint: 1 OUT (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 32

 

[phoenixdogfan]

I agree with you. "Where and how to control master volume and relative gains" is always one of the important issues in multichannel multi-amplifier systems, including my project using JRiver (or Roon), software crossover EKIO, DAC8PRO and multiple integrated and/or power amps.

Just for all of your reference, I prepare and use my "Check Sheets" like this in my project with integrated amps;
View attachment 97271

and for power amps, like this; View attachment 97272

As you can see, I am just using JRiver MC's (or Roon's) volume controller as "Master Volume Controller" in the entire multichannel multi-amplifier system. And, in the downstream, all of the red numeric numbers are the adjustable/controllable gains and/or volumes.

The software crossover EKIO's many gain values can be saved as "EKIO configuration file" of any file name, and also the DAC8PRO's gains are saved on "hard and soft shutdown" and they are retrieved on next power-on.

If needed, please visit my thread post #283 and thereafter for further details.

I notice you're using Asio for all and/or VB Audio Virtual Cable to connect JRiver to Ekio. Is that necessary? Couldn't Wasapi Exclusive mode be employed instead? What are the advantages of using your approach vs. Wasapi?

 

[dualazmak]

I notice you're using Asio for all and/or VB Audio Virtual Cable to connect JRiver to Ekio. Is that necessary? Couldn't Wasapi Exclusive mode be employed instead? What are the advantages of using your approach vs. Wasapi?

Well, I have "historical" and "practical" reasons for sticking to "all in ASIO I/O" in my PC based multichannel audio system.

I started to use 192kHz 24bit USB DAC in 2009, the first one was RATOC RAL-24192UT1 on Windows 7 Pro 64 bit PC. After that I purchased ONKYO DAC-1000, KORG DS-DAC-10, OPPO SONICA DAC and finally OKTO DAC8PRO, with Windows 7, Windows Vista, Windows XP and Windows 10.

Throughout the usage of these DACs with Windows PC, I have been always sticking to ASIO I/O fully independent from Windows OS audio services including Kernel Streaming, Direct Sound and WASAPI; as you may know, there have been several confusions, change of policies and inconsistency problems with Windows audio services especially associated with the major version-up of the OS, i.e. 7 to Vista, Vista to XP and also XP to 10.

Even though current WASAPI Exclusive mode on Windows 10 maybe be quite OK, I experienced uncomfortable and sometimes nearly harmful (to my speakers) kernel sound intrusion incidents when I used Kernel Streaming, Direct sound or WASAPI (non-exclusive), and therefore, I still do not fully trust Windows OS oriented sound I/O services including WASAPI Exclusive. I also heard in Japanese audio enthu forums that several recent major update of Windows 10 caused unexpected initialization(?) and/or inconsistency problems with WASAPI service.

As far as we use full USB ASIO I/O with using each of the specific DAC dedicated ASIO driver, we can avoid any problems/issues associated with Windows updates. In other words, I always would like to eliminate (or minimize) Microsoft's direct involvement in audio I/O.

As for ASIO4ALL....
ASIO4ALL is a quite unique "software/driver", and looking from music player software including JRiver and Roon, it also behaves as if one (virtual) USB hardware audio "device".

ASIO4ALL sits/dominates in front of all the available other ASIO drivers, and together with VB Audio Hi-Fi Cable and ASIO Bridge, we can establish very flexible unlimited number of I/O routings with "independent" crossover software EKIO which has simple intuitive GUI capabilities. Almost all of the EKIO's DSP features, including the XO filter configurations, can be changed while listening to the music.

Especially I like the flexible EKIO-ASIO4ALL output capabilities; with ASIO4ALL, we can assign any of the available USB ASIO drivers for output channel of EKIO, and with EKIO's unlimited number of I/O settings, if needed, we can assign multiple channels into one single DAC, or one output channel into multiple DACs, and the mixture of these. Of course, if we like (even the synchronization issue exists), we may simultaneously assign outputs into multiple DACs, e.g. 8 channels of DAC8PRO plus OPPO SONICA DAC plus DS-DAC1000 plus DS-DAC-10. Or we may very easily inter-change these multiple DACs.

Since this is "DAC8PRO review" thread, I feel, if needed, we may better to continue this discussion in my multichannel multi-amplifier thread.

 

[ChrisPL]

If you set the device volume as "device" in roon, roon will apply the volume from its vol slider setting before sending this to the DAC which will then apply its own volume control setting that it displays.

I was mistaken, when roon "My Device" volume control is selected, the volume slider does not affect the actual output but it does changes the amixer volume values for all 8 channels of the DAC8PRO. Sorry for the confusion.

Maybe firmware version 1.42 would then have roon control the actual volume output. You can display the individual channel volume values via the DAC8PRO volume menu, it would be interesting to see if these values compare to the amixer values with firmware 1.42.

This is what I get after setting the roon vol slider to 49% with roon DAC8PRO volume configured to "my device"

pi@raspberrypi:~ $ amixer -c3
Simple mixer control 'DAC8PRO ',0
Capabilities: pvolume pswitch
Playback channels: Front Left - Front Right - Rear Left - Rear Right - Front Center - Woofer - Side Left - Side Right
Limits: Playback 0 - 99
Mono:
Front Left: Playback 81 [82%] [-18.00dB] [on]
Front Right: Playback 81 [82%] [-18.00dB] [on]
Rear Left: Playback 81 [82%] [-18.00dB] [on]
Rear Right: Playback 81 [82%] [-18.00dB] [on]
Front Center: Playback 81 [82%] [-18.00dB] [on]
Woofer: Playback 81 [82%] [-18.00dB] [on]
Side Left: Playback 81 [82%] [-18.00dB] [on]
Side Right: Playback 81 [82%] [-18.00dB] [on]
Simple mixer control 'DAC8PRO ',1
Capabilities: pvolume pvolume-joined pswitch pswitch-joined
Playback channels: Mono
Limits: Playback 0 - 99
Mono: Playback 10 [10%] [-89.00dB] [on]

Looks like roon sees the 'DAC8PRO ',0 and controls all channel vol values.

 

[DrCWO]

This really looks promising, so roon can change the volume inside the DAC. Did you also hear the volume change, meaning the level uf the percieved music decreases?
If yes, is there a change at the display?

 

[ChrisPL]

No, unfortunately not with my unit, firmware version 1.4

In my case, both master and individual channel play back volume controls appear to be available via usb driver however they do not work as changing the playback volume values has no effect on the DAC8PRO ( no change on volume output or displayed volume ) .

Maybe some of this has been further implemented or fixed in firmware version 1.42 ?

 

[Vincentponcet]

Any news for the firmware update tool ?

No news of the firmware update tool?