[3stun]

 

- what are the diffs between v1-v2-v3 and how exactly do I recognize them?

 
From what I know, v1 has a black volume knob:
 

 
While v2 has a silver one and also a sticker saying "MyST 1866 port":
 

 
 

 
As for v3, I believe it looks just the same as v2, although not sure 100%.
 
Now about technical differences.
From what MyST revealed on russian forum:
- v1 has a very weak BT module, works fine only at close distance (30-40cm). v2 has improved BT module (probably this one).
- v1 and v2 drain your smartphone battery when connected to USB via OTG (unless you block +5V line on your OTG cable or use custom cable), v3 has a special mode where it doesn't drain USB source battery (instead works completely on internal battery).
As for sound hardware, it seems like all three versions are the same.
 
As a proud owner of OCUB 1866 v1, I welcome questions about it.
 
I've been comparing OCUB 1866 v1 via different inputs, and found that USB sounds noticably better than others. No idea why, since USB receiver is supposed to be inferior in quality to COAX and OPT. The difference is so big for me that I had to sell my COAX transport (kept specially for OCUB) and buy a cheap smartphone supporting "music-over-USB".
Some users on russian forum notice this difference, and some don't.
It is possible that v2/v3 have different receivers, so my observation could only be true for v1.
 
People say you can use Sony A15/A17 as transport for OCUB (with NWH10 cable, which you need to buy separately), but it didn't work for my OCUB v1. No idea why.

 

[prot]

Manx thx 3stun that's exactly what I wanted to know about the v1-2-3 differences.
Amd btw, what kind of cheap smartphone with Usb support can you recommend?

 

[3stun]

Manx thx @3stun that's exactly what I wanted to know about the v1-2-3 differences.
Amd btw, what kind of cheap smartphone with Usb support can you recommend?

I'm using Alcatel POP C7. To use it as USB transport you need to purchase & install USB Audio Player PRO.
The drawback is low battery life. With standard USB OTG, OCUB 1866 consumes smartphone's battery in a few (2-3) hours.
Using custom cable (5V line blocked) doubles (or more) battery life.
 
Also, you might want to check this thread.

 

[prot]

Finally found a relatively cheap Tento on ebay and been using it for the last month. Couldnt be happier.

It drives pretty much any hp I've thrown at it, even the sennheiser hd650 & hd800S sound good/loud enough out of it. Works best with hp-s with somewhat higher impedance .. and with planars. The he400i sounds just perfect out of it.
The sound is very enjoyable and I have no ear fatigue anymore (very sensitive ears here and most other portable Dacs were unconfy to my ears on long listening sessions) .. the highs are recessed according to measurements but I dont really feel like I am missing anything .. all the details are there, they are just not fatiguing anymore. And the bass is very strong, detailed & punchy .. matches perfectly with the hd650/800S.
Like said, very happy with it .. the new price is very high but this is the best portable I heard. I would say it's worth the money. And the bluetooth connection is very good, even on an older, no-aptx device like mine.

One question though. My device only accepts max 16/48 over Usb ... but the Tento website says 24/48 .. am I missing something? (settings, drivers, etc)

 

[shigzeo]

The USB receiver is capable of processing 24-bit at 96kHz but the DAC itself is 16-bit 48kHz. From what I understand, it is re-sampled. 

 

[prot]

The USB receiver is capable of processing 24-bit at 96kHz but the DAC itself is 16-bit 48kHz. From what I understand, it is re-sampled. 

Thanks for the info.
I find the specs/numbers quite confusing. According to some online info the device has an 24/192 receiver chip. And coax does accept 24/192 without issues.

Also the Dac chip is indeed 16 bit but the specs mention 8x oversampling so 192khz should be no problem and freq downsampling should not be needed... the 24 bits can be simply truncated to 16 (or dithered).

As about Usb, 24/96 would be very good but my device doesnt want to go over 16/48. Tried on 4-5 PCs already (win7 and win10) with the same results. Either I have an old model or my device has some issues. I may ask Tento about it.

Anyone who can bring some light here?

 

[Noloben]

I can see some misunderstanding here. Let me clarify. Optical and coaxial inputs are able to recieve up to 24/96 and 24/192 respectively even though it downsamples it to 44.1, but frequences multiple to 44.1 are better because it's the frequency DAC works with. However, USB and BT can't work with 44.1 by their specifications! So the DAC have to resample recieved stream to make it suitable for AD1866, and that's why you can see noticable sound degradation. By the way, that's also the reason why you should never use Fiio X3 (I) as a source of digital signal. It just doesn't support frequences multiple to 44.1.(Fixed in Fiio X3 II as I heard)