Review and Measurements of Okto DAC8 8Ch DAC & Amp

[Dacapalooza]

BTW: The Furman ammeter works the best out of all the others I tried. It truly goes faster than human eye. I took movie of Tron and moved frame by frame. Tron is the loudest movie in history if Furman is correct. I'm 4.5 amps when mute. Movies rarely go above 10. I don't know how I didn't blow a fuze going up to 20 amps in Tron? Is power stored in the linear doughnut in the the Furman?
I got new service after Sandy destroyed last one and forgot to upgrade the media room's CB to 20a so only have 15. My new service is also always +-2 from 120. So using the voltmeter I got from Amazon, the Furman always outputs 120v as their spec claims. Admittedly, I got the Furman for its ammeter, so nice bonus that it always outputs 120v.

 

[bigjacko]

My custom cable came, so I am Okto install DAC . Came out very nice. Vanity has this weird termination, I made the diagram below. I already had custom cable but without DAC connection so made new one. This time I made them with labels that match the Oppo labels.

View attachment 62188

View attachment 62186

What is the connector in the end? By the way, okto research had some comment about xlr to rca, the pin three from xlr should be floating. Here is a quote rom okto research:


When interfacing XLR outputs to RCA inputs, you have these options:

1) The best one from a technical standpoint: retrofitting a XLR differential input to a legacy equipment
It might be either built inside or made as an outside box with separate power. The XLR shield and pin1 would need to be grounded to the chassis on the receiving side or the whole thing might be bolted to it. A company called THAT Corporation makes very good receiver chips that would fit this task and a module using those has even been a commercially available product at some point .
https://www.neurochrome.com/that-receiver-rev-1-0/

2) A drop-in solution if you don't mind some distortion: tranformers
The transformer-based approach (like with Neutrik NA2F-DOB-TX or much more expensive Jensen transformers) will work and avoid ground loop issues. Transformers also have higher common-mode rejection ratio than what can be achieved with semiconductors. The distortion might not matter for use with tube amplifiers that already have a transformer in the signal path or with subwoofers.

3) Off the shelf XLR-RCA cables
As mentioned, these short XLR pin 3 (cold) to pin 1 (ground). That makes them work both with direct-coupled and transformer-coupled XLR inputs/outputs, but the direct-coupled ones might not be happy about the short. While the outputs of DAC8 PRO are short-circuit proof, operational amplifiers do not like huge loading and will respond with increased distortion (by several orders of magnitude).

4) Cable with floating pin3 (cold)
Using just one of the signals from the XLR side to interface with RCA is a dirty and cheap solution. We cannot guarantee this will be hum-free (depends on circumstances) or that DAC8's output will be pop-free on turn on/off in this configuration, but it is certainly a better way than the previous one. There will still be an increased distortion compared to interfacing a regular XLR input since you will be picking up the common-mode distortion products that would otherwise be rejected. Because you are only taking half of the signal, you will lose 6dB. If you still want to go that way and don't have pliers, Benchmark already makes cables like that: https://benchmarkmedia.com/collecti...dapter-cable-pin-3-floating?variant=547761981

 

[Neddy]

I assume he's sending it AES from the Vanity (The 4 xlrs.)
Nice cables, by the way.
Mine also got stuck in customs ...Fedex had to call and ask what a DAC was too!
Cute furman ammeters - hadn't thought of that approach.

 

[jjk]

Dac,
Which Oppo do you have? A 93?
The connections are slightly different on a 103.

edit...maybe it is the 203?

 

[bigjacko]

Oh didn't realize the cable is for vanity board. What is the benefit of using vanity board?

 

[Neddy]

AES output from Oppo BR

 

[bigjacko]

The measurement is done by using USB and showed great result. Adding a vanity board would add cost. What is the benefit of using AES? Can you do some DSP on vanity board?

 

[Neddy]

As discussed earlier in this thread, the vanity boards add AES outputs to the Oppo BR players, which is the only way to get HiRes digital mch audio out of it.
That then gets fed to the Okto, re-routed to a PC for DSPing via USB, and then back to the Okto for DAC'ing.
A very slick solution...wish I could have found one of the vanities (bonfires or not), but have found what looks like a decent ADC (Motu Pre) to simply convert the Oppo's analog outs to USB. Won't be nearly as hi-res as the Vanity/AES, but I'll only use it for movies and Roku streaming.
Starting on ripping my SACDs and a few BRAudios per Kal's article today....

 

[lkong]

Ordered mine yesterday, now it's time to research digital crossover software. Any recommendations?

 

[dualazmak]

Ordered mine yesterday, now it's time to research digital crossover software. Any recommendations?

Hello lkong,

In my mutli-channel project with DAC8PRO, I am using digital software crossover EKIO which features very much flexible unlimited I/O routing. Even though EKIO's processing is in 192 kHz 24 bit, the overall sound quality is really nice, and we can do almost everything with EKIO on Windows 10 PC, just like the extraordinary expensive TRINNOV ALTITUDE 32 which also runs in 192 kHz on UNIX. Your visit and participation in my thread entitled "Multi-Channel, Multi-Amplifier Audio System Using Software Crossover and Multichannel-DAC" will be quite welcome.

 

[Kal Rubinson]

As discussed earlier in this thread, the vanity boards add AES outputs to the Oppo BR players, which is the only way to get HiRes digital mch audio out of it.

In addition to HDMI, of course.

 

[Neddy]

Ordered mine yesterday, now it's time to research digital crossover software. Any recommendations?

In a way, it's nice there's a bit of a lead time for delivery to give you time to prepare!
There are probably hundreds of options for xovers, so knowing more about your setup might help narrow it down.
Are you ok with steep learning curves on complex software? PC software, or is an outboard (or even downstream, like mine) solution ok?

Kal, you are of course correct about HDMI (duh).
My 'solution' to 'how to get DTS/TruHD decoded Mch audio into my OktoDAC' arrived today.
More on that later...if it works:>

 

[lkong]

In a way, it's nice there's a bit of a lead time for delivery to give you time to prepare!
There are probably hundreds of options for xovers, so knowing more about your setup might help narrow it down.
Are you ok with steep learning curves on complex software? PC software, or is an outboard (or even downstream, like mine) solution ok?

Kal, you are of course correct about HDMI (duh).
My 'solution' to 'how to get DTS/TruHD decoded Mch audio into my OktoDAC' arrived today.
More on that later...if it works:>

So yeah, some background of my setup here:
full range: quad ESL-63
dual-sub: linkwitz dipole.
software: HQplayer + HQplayer NAA
I'd prefer something which is compatible with HQplayer for "serious listening". Also, should run with streamer OS like volumio for "casual listening".

 

[bigjacko]

As discussed earlier in this thread, the vanity boards add AES outputs to the Oppo BR players, which is the only way to get HiRes digital mch audio out of it.
That then gets fed to the Okto, re-routed to a PC for DSPing via USB, and then back to the Okto for DAC'ing.
A very slick solution...wish I could have found one of the vanities (bonfires or not), but have found what looks like a decent ADC (Motu Pre) to simply convert the Oppo's analog outs to USB. Won't be nearly as hi-res as the Vanity/AES, but I'll only use it for movies and Roku streaming.
Starting on ripping my SACDs and a few BRAudios per Kal's article today....

Thanks for explaining, but I still don't understand the benefit of using vanity board or using AES output. I think we can use USB to PC and then use DSP software like Equalizer APO to do xover. Is this a valid way? I am also interested in active xover so want to explore more.

 

[dualazmak]

So yeah, some background of my setup here:
full range: quad ESL-63
dual-sub: linkwitz dipole.
software: HQplayer + HQplayer NAA
I'd prefer something which is compatible with HQplayer for "serious listening". Also, should run with streamer OS like volumio for "casual listening".

Hello again, lkong,

Please take your time for research on your selection and trials of software/hardware crossover solutions. Just for your info, the flexible I/O of EKIO enables "serious listening", and also "casual listening" including streaming web radio as well as YouTube.

As for the lead time to get DAC8PRO, in my case, I placed my order on February 15 and will receive it on Monday May 11 here in Chiba Prefecture, Japan, even under the serious COVID-19 pandemic status. It is now at FedEx Office at Tokyo Narita International Airport, and FedEx just informed me they will deliver it to my home on Monday.

 

[Neddy]

Thanks for explaining, but I still don't understand the benefit of using vanity board or using AES output. I think we can use USB to PC and then use DSP software like Equalizer APO to do xover. Is this a valid way? I am also interested in active xover so want to explore more.

For multichannel systems, the issue is about decoding TruHD/DTS-HD Mch audio from Bluray discs, which can only be done on either a bluray player (Oppo, for instance), or an AVR/Pre-pro (or other devices that have the licensed decoders). It's an HDMI copy protection limitation.

Those devices only output HDMI or analog -no digital 'hi-res' mch, so, no way to get that into a PC and thence to the OktoDAC via USB.
The Vanity board modification does (did) that, via AES, and happily (for some) the OktoDAC accepts that...AND can route it back to a PC for further manipulation.

The other route would be to convert the player/AVRs decoded analog outputs back to digital via USB, and then route that to the Okto - this the approach I'm taking (I'm only using that for movies, not as concerned about HQ audio there, and will (trying to) rip my BRAudio and SACDs to files. Lip sync may be an issue with that - I should know soon.

If you have no interest or need to get multichannel hi-res output from Bluray (movies or audio), or SACDs to your OktoDAC, then it is NOT an issue.
(As pointed out previously ripping Bluray or SACDs to file is another alternative, but seems to be a laborious process I have not gotten to work yet...but would be fine for BRAudio/SACDs and the few movies I think are worth the effort.)

Hope this helps - also discussed in more detail/accuracy in these threads:
https://www.audiosciencereview.com/...are-blu-ray-players-still-worth-buying.12061/
https://www.audiosciencereview.com/...-and-understanding-some-basic-concepts.11346/

On the active xover topic, don't forget that the OktoDAC also outputs AES (Ch1 & 2), which can be routed to compatible hardware devices downstream of the Okto, which is what I have done, for xovers and roomEQ for my mains. Just one of lots of options, there.

Hope this helps?

 

[Kal Rubinson]

(As pointed out previously ripping Bluray or SACDs to file is another alternative, but seems to be a laborious process I have not gotten to work yet...but would be fine for BRAudio/SACDs and the few movies I think are worth the effort.)

Depending on what Oppo you have, it can be trivial, imho.

 

[Neddy]

Kal, sure sounds straightforward, but I keep getting errors when it tries to read the Oppo103.
Where's the best place to get detailed advice/help on this?
- Oppo can read file shares on either PC
- Oppo reacts properly to the boot-loader
- ISO2DSD runs fine, but errors out with 'can't access device' errors, on either PC (W7, W10); acts like an IP address error, but can see it fine from both PCs, and vice versa.
- Bummed.
Thanks for the great instructions in your article, BTW, very helpful!

 

[Dacapalooza]

Dac,
Which Oppo do you have?

I have 1 * 103 & Vanity HD 103
I have 2 * 203 & @ Vanity HD 203 v1.4
The second 203 is for backup as my entire system depends on the Vanity. I expect all to fail within 7-8 years. I hope by then a decent processor will exist. Although, my goals will never be achieved again. I want dedicated DAC.

I assume he's sending it AES from the Vanity (The 4 xlrs.)
...Cute furman ammeters - hadn't thought of that approach.

I use AES. The latest Vanity 203, version 1.4 is user configurable for SPDIF/AES. Previous versions you had to specify when ordering.
Ammeter is essential. Great debugging tool. I know instantaneously when something is wrong when I don't have the normal power usage. Also most important in calibrating. Post calibration, I test movies with high power usage. When Scenes use too little/much power I know something went wrong with the readings. Ambient noise, SNR, cabinet resonances, PC background processes, etc. A lot goes wrong with readings.

Oh didn't realize the cable is for vanity board. What is the benefit of using vanity board?

Many. The most important being is I can route my Blu Ray's to any component I want. To a DAC of my choice. To RC device of my choice. Audio geek wise, Vanity is the best way to get audio signal from BD. Not using transformerless evil HDMI, & the transformer coupled AES audio is decoupled from AV by buffer/re-clocking.

The measurement is done by using USB and showed great result. Adding a vanity board would add cost. What is the benefit of using AES? Can you do some DSP on vanity board?

PC software still can't do 4K correctly so USB won't help.
I suppose USB is useful for audio only, but I imagine no one cares? Who just sits in a room and listens to music? Anyway, I would never put a PC in my audio chain. I want the best components made from the ground up for a singular purpose that humanity has to offer. PC's are hardly dedicated.
Vanity is cheaper than a decent PC. AES is what mission critical pros use. Music/movies are created using AES. Arguably the best audio connection there is.
Yes, the vanity has access to DSP. The Vanity hijacks the signal intended for the DAC, so Oppo's crossover, trims & volume is available if you want it. If you use a PC you have to +10db from LFE as BD has this weird habit of using -10db in BD's. Sometimes I feel Hollywood is just messing with us. So even though, Vanity advertises bit perfect from source, there is no way to defeat oppo's LFE +10db correction when needed.

 

[Dacapalooza]

In addition to HDMI, of course.

Kal, you are of course correct about HDMI (duh).

Yes & no. Technically you can use HDMI for MCH and seemingly work. But all HDMI DAC implementations are broken except for an Anthem model & usually worse than the Apple dongle according to the host. I don't think any HDMI DAC clears 24 bit rate, so the DAC is down-rezing. So HDMI high rez audio is impossible today.

Also HDMI is a closed system. So it's like saying Jail is also option to live. Actually a broken jail at that.

Discontinued Correction: For full high-rez HDMI DAC: You can use HDMI input of the discontinued Oppo 205. You can even have room correction with the discontinued HDMI NanoAVR providing you don't actually use the Oppo for BD . Also no crossover is possible so not really a solution. I have the NanoAvr an if you do crossover downstream the calibration breaks.