[jarnopp]

Hey guys,

I wanted to connect my Mojo to an external amp using the line level mode (press both volume buttons while switching on). As per the manual, the volume balls should illuminate light blue but mine doesn't, it lights up in purple. What gives? Also, if I turn it off and turn back on, it stays on purple when supposedly it should be reset back on previous volume before it was set to line level mode, no?

This is what line out looks like. (Picture taken on dimmed ball setting.) There can be some variation. If you adjust the volume at all after using line out, that will become the new setting when turning back on. Line level is just a shortcut to manually setting the volume.

https://www.head-fi.org/threads/cho...n-3rd-post-◄★☆.784602/page-2312#post-13902019

 

[bunkbail]

This is what line out looks like. (Picture taken on dimmed ball setting.) There can be some variation. If you adjust the volume at all after using line out, that will become the new setting when turning back on. Line level is just a shortcut to manually setting the volume.

https://www.head-fi.org/threads/chord-mojo-dac-amp-☆★►faq-in-3rd-post-◄★☆.784602/page-2312#post-13902019

Thanks. That cleared some things up. I guess line out just sets volume/voltage at 3V, but not bypass the amp section of Mojo (is there even an amp section in Mojo?).

 

[GreenBow]

Optical s/pdif isn't without it's problems and many would say it's much more jitter prone than USB whereas USB runs into problems on the receiving end if there is a lot of noise and it amps up the processing ... Schiit clearly seems to be going the USB route, choosing to clean up the USB and then outputs to coax s/pdif in the Eitr and recently adding in its Gen 5 USB. There's also rumors they're working on their own USB chipset to handle the processing load.

I started out using optical on the mojo out of my MacBook but have switched to USB as I notice no difference in light A/B testing and USB is just much more convenient. As for the Hugo, I just don't get the argument for it when you could buy endgame DAC & tube amp for the same price or multiple of them (e.g. woo audio WA2 and schiit gumby) or if you need transportable you could get woo WA8 and new set of nice headphones. But the heart wants what it wants.

Well Chord DACs are immune to jitter, as the samples are re-clocked inside the DAC at the correct sampling frequency. Therefor making optical the most likely to be most accurate, if file storage device is noise free.

I am exploring USB clean up, of the power lines. I think I am going to get a JitterBug, or WYRD. If it improves the signal even slightly, it will be worth it. The Chord Mojo is stunning, and I know it's signature well on USB, so I should spot any improvement. I think the noticeable gains are more solidity, and a bit more clarity. ..........

In the case of optical. I think it will be a matter of getting the signal through a device which creates the optical signal. One that doesn't suffer USB noise. I am actually thinking it might be best to get a sound card that specialises in being shielded. Or put a JitterBug or WYRD on an external USB to optical converter.

(There is a very strong argument for getting rid of noise. If it's the case that it messes up the signal processing or samples. I guess it only takes one bit (of a byte/packet/sample) to be off, and one sample is lost. ... I was recently doing some work in Cubase. I discovered that changing one sample point even fractionally was noticeable, if you knew previously how it should sound. .. Anyway that's all for another thread.)


I don't agree that for me, about what you said, about value for money spending. Or that there is an end game DAC and amplifier worth buying at the price range you suggest. Of Chord Hugo £1,400, or Hugo 2 £1,800. Maybe in the world of headphone amplifiers, but not in the world of regular hi-fi amplifiers. A headphone amplifier would be useless to me, as I only use headphones part of the time. Then when I use headphones I plug them into the DAC. Waste of money buying a headphone amplifier then, since you gain nothing from using one. The further you travel from DAC to headphones, the more signal you lose. If you are happy with Chord DAC, you use that.

In terms of DAC cost alone, the Hugo TT was widely regarded as setting the standard at its price, when reviewed at £3,000. Yet some feel the Hugo 2 outperforms the Hugo TT. I guess either DAC would make someone happy, but neither are acknowledged as end game. They are close enough, to be extremely happy to live with though, and 'feel end-game' though . However not end game, since everyone is aware of the Chord DAVE anyway.

 

[musickid]

i don't think a usb to spdif interface will sound any different to optical straight out of a computer. in fact the convertor might introduce problems by messing up the clock reference used by the dac and the clock in the spdif of the computer. my description needs improving here.

 

[GreenBow]

i don't think a usb to spdif interface will sound any different to optical straight out of a computer. in fact the convertor might introduce problems by messing up the clock reference used by the dac and the clock in the spdif of the computer. my description needs improving here.

I am not sure whether putting a USB clean-up on a USB-to-optical device, would mess anything up. No idea. However I don't think that the DAC controls SPDIF asynchronously. I think the bits a totally sent and controlled by the computer. I think the DAC is simply sat on the end and sees the light patterns coming in. However the samples are iso-synchronously dealt with, by Chord DACs, (meaning clocked).

I presume this is the case with optical. I doubt my Mojo sends talk to my desktop digital radio, when it gets optical from it.

I don't have an optical output on my PC. Only a header on the motherboard. Or I will use a sound card, or an external USB>optical.

 

[Light - Man]

I was referring to the Mojo from the "off" position or cold state.

Indeed! It is fluffing freezing here also!

 

[GrussGott]

Well Chord DACs are immune to jitter, as the samples are re-clocked inside the DAC at the correct sampling frequency. Therefor making optical the most likely to be most accurate, if file storage device is noise free.

That doesn't sound consistent with what I know about USB versus s/pdif, i.e., USB agrees upfront versus s/pdif which has to agree with every sample, but I haven't dug into it much deeper than that. (actually I have I just don't remember the details) nevertheless, saying that any device is "immune" from jitter seems risky. I know Rob prefers the sound of optical, I've heard other say the opposite, but the industry is clearly going USB. That may be for convenience, but I've read (and forgotten) many technical arguments about why USB is the better standard.

 

[AndrewH13]

That doesn't sound consistent with what I know about USB versus s/pdif, i.e., USB agrees upfront versus s/pdif which has to agree with every sample, but I haven't dug into it much deeper than that. (actually I have I just don't remember the details) nevertheless, saying that any device is "immune" from jitter seems risky. I know Rob prefers the sound of optical, I've heard other say the opposite, but the industry is clearly going USB. That may be for convenience, but I've read (and forgotten) many technical arguments about why USB is the better standard.

Just to throw a spanner in the works, I always prefer s/pdif Coax
Talking Mojo and Hugo 1 and 2 with DAPs, and Hugo from Sonos into 2 channel hifi. But never use laptop for music which may be different. But no need for anything wrapped round cables, no limited bandwidth problems, just good sound.

 

[GreenBow]

I'd like to have USB, optical, and coaxial, as options to use. It makes sense to me then to have all the options working at their best.

I don't understand how you don't reason why Chord DACs are immune to jitter. Jitter is a timing error. Chord DACs re-clock all the samples using a very accurate clock. You're going to have to use the search function on the thread to find out. I can't explain it any other way. It's been covered because I remember double checking it myself, and Rob Watts answered.

I think you're right about USB needing to agree data sent was correct. I am sure I read that Chord DACs resend for data if there is an error. ... However my purpose of wanting to clean the USB line, isn't to corrects those kind of errors. It's to correct noise within the DAC, that gets in via USB power lines.

 

[GreenBow]

Just to throw a spanner in the works, I always prefer s/pdif Coax
Talking Mojo and Hugo 1 and 2 with DAPs, and Hugo from Sonos into 2 channel hifi. But never use laptop for music which may be different. But no need for anything wrapped round cables, no limited bandwidth problems, just good sound.

I think going off what the conversation has been recently, that you're right. Please could you remind me in a few words what USB vs optical, for you is like.

(Sorry, but I can't remember the qualities that people say get enhanced with optical. Probably though, just better overall. I would love to hear Mojo at it's absolute best. I sounds so good as I have it now with my amplifier and (my incredible to me) desktop speakers.)

 

[AndrewH13]

I think going off what the conversation has been recently, that you're right. Please could you remind me in a few words what USB vs optical, for you is like.

(Sorry, but I can't remember the qualities that people say get enhanced with optical. Probably though, just better overall. I would love to hear Mojo at it's absolute best. I sounds so good as I have it now with my amplifier and (my incredible) desktop speakers.)

My experience is there is little between the three, provided all are at their best. But coax just has so little to go wrong, so you know you don't need to modify it. I've used DACs in my hifi (improving CD and later streaming) from the first Arcam Black Box, liked Rob's Deltic DAC, to more recently Rega and Naim DACs, then Mojo and Hugos with a special word for TT that I had for review. Whenever there was the option of Optical and Coax, I always found Coax more engaging. I know Rob has a slight preference for Optical, but then Rob likes some warm headphones that I find a bit soft!

 

[AndrewH13]

Regarding USB, I've only recently used it, prefering Daps to computers as a source. Few months ago I bought a Pioneer Dap going cheap and use it alternating with a Questyle QP1R via Hugo into Tag McLaren hifi. The Pioneer uses USB, the Questyle Optical. I can't hear any difference, so believe I am hearing Hugo coping with a good signal from both.

But Mojo and Hugo II are connected to ibasso and fiio Daps via very short Coax for iem and headphone listening respectively.

Like you say, good to have a choice of all three methods of connectivity.

 

[GreenBow]

Regarding USB, I've only recently used it, prefering Daps to computers as a source. Few months ago I bought a Pioneer Dap going cheap and use it alternating with a Questyle QP1R via Hugo into Tag McLaren hifi. The Pioneer uses USB, the Questyle Optical. I can't hear any difference, so believe I am hearing Hugo coping with a good signal from both.

But Mojo and Hugo II are connected to ibasso and fiio Daps via very short Coax for iem and headphone listening respectively.

Like you say, good to have a choice of all three methods of connectivity.

Ahh, yes I think that USB on a computer is going to be substantially worse than a DAP. I clearly recall Rob Watts telling us that PCs are (very) noisy.

I also read him saying he found his laptop quiet, on the USB. Being due to laptops requiring less power as they have evolved. Also I think I recall him saying, something about being happy with optical and USB on it. ...... Overall though, I think the residing issue was that with noisier sources, that optical was better than USB. I think that's what it was.

Sorry I didn't mean to be nagging you for information or data. I just couldn't recall the words folk used to describe optical vs noisier USB, or USB generally.

No worries but thank you a lot, anyway.

 

[AndrewH13]

Ahh, yes I think that USB on a computer is going to be substantially worse than a DAP. I clearly recall Rob Watts telling us that PCs are (very) noisy.

I also read him saying he found his laptop quiet, on the USB. Being due to laptops requiring less power as they have evolved. Also I think I recall him saying, something about being happy with optical and USB on it. ...... Overall though, I think the residing issue was that with noisier sources, that optical was better than USB. I think that's what it was.

Sorry I didn't mean to be nagging you for information or data. I just couldn't recall the words folk used to describe optical vs noisier USB, or USB generally.

No worries but thank you a lot, anyway.

Just A Coincidence, but we both have made the same amount of HeadFi posts

 

[Rudivanb]

@Rudivanb

I think I may made a mistake over the battery charging, and reconditioning the battery issue.

I have found that my Mojo will give me 7hours 15 min from charge light going out.

However it gives me the full eight hours and fifteen minutes, that it did originally when new, under different charging. This is from full charge, where it's been left on charge after the charging light goes out.

Apparently once charged, the Mojo charging light goes off, then continues on trickle charge for a while. Thus topping up the battery further. I think this is what I understood from Rob Watts posts, but sorry if I am wrong.


Either using your technique did recondition the battery. Or when I was seeing about 7 hours fifteen minutes playing time. It was from only charge until the charging light goes out.


My apologies genuinely to anyone if I have misled.

Or it was sheer luck on my side.
BTW I do fully discharge the battery sometimes during normal use, as I forget the re-charge ;(