[Whitigir]

I tried Onkyo app with mojo. It only stutter when up converting. The bad thing is that up converting is standard, just go into setting and don't up convert it, just turn the option off

 

[Dobrescu George]

George - As far as I know there's no packet verification when transmitting audio signals from a transport to a DAC like there is with traditional digital data transmission. It's a live, one way stream - there's no error correction or resend requests or such. That's one reason why sources and cables do make a difference in this type of USB use in audio application as compared to TCP/IP, etc. Happy to be corrected but that's how I've always understood it. Cheers

Wow. I never thought that data transmitted to USB DACs will not ask for packet verification. 
 
It seems that it is true and handshake packets are different in USB when used in Isochronus transfers. Because audio is supposed to be in real time, they do not verify packet integrity, so data can be lost along the cable, or worse, or interference. I was not aware of that, thanks for pointing it out. In fact, I always believed that all usb work the same. Also, with USB 2.0 and 3.0 out (over 10mb/s or bulk data possible) why was this never changed to everything-bulk-transfer?
 
When used in BULK, USB connections will not take latency into account, and will verify files for integrity, each packet gets a handshake for verification, and data rate is not taken into account. 
 
In this situation, it seems simple to me, how it should be done 

. The company who builds a USB DAC should use a large buffer RAM inside the DAC, to store the file (like 256mb) , transfer the file using BULK connection, then use Interrupt transfers to communicate with the software which does the decoding, to ensure something like changing the song, or seek in file. This should work wonders, and then cables would not matter any more. The downside would be that something like a Fiio X5II, which does not output BULK but rather co-aux data stream would not be able to serve as a source for files, and only devices which can transfer files would be able to be used. 
 
[ / RANT! / Why the heck did co-aux ever started to be used if it was flawed from the design? I mean, really, come on, data is lost in the process, like it or not. Why not send the files in Bulk instead of Isochronus, and use pointers for other file operations? That is just messed up. This will be hard to clean later, opening the market for overpriced audiophile cables /End of Rant/ ]
 
You know, actually, if a company really cared, would implement the ideea stated above, but most will not, because implementing that would mean that transport will not make a difference, and cables will not make a difference. Come on.I was better not knowing this and dreaming that everything was perfect 

.
 
But now, for real, I can make a few things in my software to make sure that data is never lost, so much work to be done, and so much things to make listening to music better.  Yet software takes a lot of time to write, and I can see why big companies with lots of software development have a lot going on for them.

 

[rkt31]

hi, sorry it is very difficult to check the complete thread, can anybody please tell about the polarity of 2 pole 3.5mm pin for coaxial input of mojo ? i want to feed from fiiox3 2nd gen and i already have the pin out diagram of trrs connector for fiio x3 2nd gen. thanks !

 

[GreenBow]

  I am considering the Mojo for use mainly as a USB DAC connected to my laptop. How does the battery behave when fully charged and the device is working at the same time that the charging USB is connected? Does it keep draining the battery and charging it at the same time or does it bypass the battery and function from the power received via USB?

Also, what life expectancy would this battery have? Would it be easily replaceable by the user?

 

  It won
It won't by pass, mojo takes power only from Battery.
According to John Frank, Life expectancy of Battery in Mojo is around 10/15 Years.
And yes, it's easily replaceable. 

 
The Mojo does not only take power from the battery.
 
If plugged in and charging the Mojo takes power from the charger to both play music and charge. If the battery is full, the charging circuit swithces off, until the battery level drops 0.2V from full. If the Mojo is plugged in, the battery full and playing music, power is drawn from the charger to play music.
 
Read the third post. I guess the link to Rob Watts's explanation of this is linked there.

 

[adobotj]

I'm using ak100ii to mojo and found out that it can only play up to 24 / 96 using toslink. Since I have a generic toslink (1.5m) that is too long, I decided to shorten it using my very limited skill and try to see if it will work.

And to my surprise, not only did it work, but now it plays 24/192 and most surprisingly, it now plays up to DSD 5.6MHz!!!

DSD 5.6MHz (note the color of the power button)


DSD 2.8MHz


24/192kHz


I'm just used a cheap 'generic' toslink cable


Of course the ak100ii uses DoP but to be able to play higher than 24/92 over toslink... is beyond my expectations for a spontaneous DIY cable project

 

[x RELIC x]

I'm using ak100ii to mojo and found out that it can only play up to 24 / 96 using toslink. Since I have a generic toslink (1.5m) that is too long, I decided to shorten it using my very limited skill and try to see if it will work.

And to my surprise, not only did it work, but now it plays 24/192 and most surprisingly, it now plays up to DSD 5.6MHz!!!

Spoiler

DSD 5.6MHz (note the color of the power button)


DSD 2.8MHz


24/192kHz


I'm just used a cheap 'generic' toslink cable

Of course the ak100ii uses DoP but to be able to play higher than 24/92 over toslink... is beyond my expectations for a spontaneous DIY cable project

Sorry but DSD is white. The Mojo is displaying 176kHz PCM (cyan colour) converted from DSD to PCM by the AK100ii.

Still, very impressive for DIY on the optical cable! Congrats!

Edit: Believe me, nothing wrong with PCM on the Mojo!

 

[adobotj]

Sorry but DSD is white. The Mojo is displaying 176kHz PCM (cyan colour) converted from DSD to PCM by the AK100ii.

Still, very impressive for DIY on the optical cable! Congrats!

Edit: Believe me, nothing wrong with PCM on the Mojo!

Yup, that's right! Thank @Relic! I was just ecstatic that I can now play music files from my ak100ii higher than 24/96 but yes, since ak uses DoP, the dsd files are converted to pcm. But still, it's so good. Ak to mojo to rhapsodio rti2 is a match made in (my) heaven!

 

[koziakauzu]

Stamina mode is disabled.

I have similar issues with my old Z1 reconverted into mojo transport.
I got rid of the problem I think, by letting the onkyo HF player upsampling the files.

 

[mscott58]

George, there are some DACs that use the buffer approach you describe, like the PSAudio Wave DAC if I remember correctly. Cheers

 

[Maus]

Has anyone had the chance to compare mojo to vali 2? Are they on equal ground?

 

[Ike1985]

Can someone whose using one of the sheathed RF shielded USB cables such as the qed reference comment on if they remove all RF/EMI? Please specify your source and proximity of source as well.

 

[jarnopp]

is there any difference in SQ between via cck and via Taobao lightning-micro-USB cable? im still waiting for that cable from taobao too.

I honestly haven't given it more than 2 minutes listen, but barring phone interference, I tend to believe there wouldn't be.

 

[rmullins08]

Has anyone had the chance to compare mojo to vali 2? Are they on equal ground?

 
One's an amp and one is a dac/amp.  Can't really compare them

 

[Ike1985]

Onkyo is OK but it doeant load cover art ~70% of the time and none of the mp3's I transfer via iTunes appear in the app.

 

[masterpfa]

I'm using ak100ii to mojo and found out that it can only play up to 24 / 96 using toslink. Since I have a generic toslink (1.5m) that is too long, I decided to shorten it using my very limited skill and try to see if it will work.

And to my surprise, not only did it work, but now it plays 24/192  

OK here's my order
2.2CM with 90 degree bend at both ends could you also coverit in Red sheathing?

Very impressed for a DIY project