[lwells]

Hello,

I have been using Mojo 2 for about ten days now and the white noise happened to me two times while listening to local files with Roon and a third time while watching a movie with VLC.
I have noticed that if you stop the song or movie and skip back a few seconds and then restart the song/movie the white noise goes away, without restarting the mojo 2. I’m using a Mac mini with M1 processor by the way. Hope it helps.

I have no idea if it is caused by some apps, I think I had at least Safari open in the background.
I will report it soon to Chord giving them as many details as possible.
Except this nuisance I’m very happy with my mojo 2.

I’m also using an m1 Mac (16” with m1 pro) with Roon. I haven’t seen this issue yet.

 

[iDesign]

Hello,

I have been using Mojo 2 for about ten days now and the white noise happened to me two times while listening to local files with Roon and a third time while watching a movie with VLC.
I have noticed that if you stop the song or movie and skip back a few seconds and then restart the song/movie the white noise goes away, without restarting the mojo 2. I’m using a Mac mini with M1 processor by the way. Hope it helps.

I have no idea if it is caused by some apps, I think I had at least Safari open in the background.
I will report it soon to Chord giving them as many details as possible.
Except this nuisance I’m very happy with my mojo 2.

I appreciate you posting this and pointing out it randomly happens during playback and not always when first connecting the devices. Interestingly, it does not happen when changing between tracks with different sample rates. There is almost certainly an issue with the way Chord DACs interface with Apple devices equipped with USB-C and the latest versions of MacOS and iPadOS. I haven’t seen or experienced this issue with iOS and that’s likely because those devices all use the Lightning port. I haven’t identified what it is that triggers these dropouts but everyone who has reported the problem thus far described the exact same behavior.

The best hope is that Apple will fix the issue through a software update— there’s nothing Chord can or will do since they don’t support simple firmware updates to their DACs.

 

[headfry]

So, having recently acquired a pair of Quad ERA-1 headphones, I find that the original AKM4495 based Shanling M6 DAP that I have is, for most listening, really good with the Quads, beautifully resolving, never harsh or fatiguing, but always very detailed, the music just flows through the setup and takes over. However, a couple of niggles have become apparent. The first is battery capacity. The M6 will generally only provide around 3.5 - 4.5 hours of streaming / SD card music listening pleasure before a recharge is needed. Secondly, the headphones need a bit more driving when the music gets lairy. The Shanling seems a little too polite for some tunes!

Bright idea, the Mojo 2 seems to perfectly fit my use case (stream from PC / Laptop / Shanling M6 or even the Oneplus 9 pro at a pinch). Lossless EQ sounds perfect for adding the last 2dB of heft to the bottom end of the Quads.

I’ve been using the Mojo 2 since last Tuesday and here are my impressions. A nicely packaged and presented bundle, the unit itself feels nicely hewn from a block of ally and the finish is excellent. The control interface balls are simple enough to learn and, for me, preferable to an LCD screen and menu system. Richard Of York Gave Battle In Vain is the simple key for adjustments. Nice touch! Brightness level is well considered, but the lower brightness still doubles as a decent night light. Micro USB? I know it is rated for 1A charging, but fast charge 3 phones were using it with 3A chargers years ago. Still have a Nexus 6 in the household using it daily.

The sonic tweaking available feels very well considered and highly useful. My guesstimate was that the Quads needed the 20Hz region boosted by 2dB and the result was perfect. Playing around with the settings, I think it would be possible to get a subtle and effective EQ for most headphones. Crossfeed is brilliant, especially for some older recordings or stuff that is heavily panned. Take Five and A Meeting By The River benefited hugely from it, with no apparent downsides.

Connectivity was simple with phone and DAP, with stored files and streaming (Amazon HD) working perfectly, with the exception of playing a DSD256 file, which stuttered and went into white noise. It was a test file, I don’t usually bother with DSD, so not an issue for me. Connection to the laptop and workstation were unusable. Serious noise problems and intermittent drops into white noise, so that is out.

So, to the sound then. I suspect I’m not going to be popular here! Having read the eulogising posts and looked at numerous online reviews, I was expecting more. Particularly, I was expecting substantial across the board improvements over the Shanling M6. Charged, played until battery hit 20% and charged again, it was time for the initial listen. Something of a recent favourite of mine, Jon Hassell’s Listening to Pictures album, has complex textures and lots of spatial trickery in the production. Initially, it felt dull and flat. Stuff was all there, or thereabouts, but the space was missing, the textures and vibrancy reduced, the magic gone.

What followed was an extensive listening session leading to the realization that although the Mojo 2 is a very good DAC, a huge improvement on my workstation output stage for example (with Asus Crystal Sound 3 no less!) it only surpasses the Shanling M6 in driving power and perhaps is a little better rhythmically with some music. In general, resolution across the frequency spectrum seems to be lower, the sound somehow thicker and the portrayal of subtle tonal and dynamic shifts compressed. Textures are less vibrant, bass seems heftier, but with reduced detail. It could simply be a lack of synergy with the Quad ERA-1 I guess? I don’t have any other decent headphones to try. Experimenting with EQ could not retrieve the missing magic.

I suspect I am going to have to reach deeper into my pocket. The descriptions I have read of the Hugo 2 sound, look to be heading in the right direction for my tastes. On the plus side, I knew the Shanling M6 was good. When I was auditioning the ERA-1 I tried them on a much more expensive front end to see how they scaled. Hooked up to a Naim / Accuphase setup, there was not much difference from the little DAP! Perhaps the ERA-1 looks a little too closely? I’m worried that a Hugo 2 sized hole is about to appear in my bank account.

Listening notes / deranged ramblings below:

All files .flac 16 bit 44.1KHz unless otherwise stated. Impressions are how the Mojo 2 sounds with the M6 as the control standard.

John McLaughlin, My goals beyond, Peace 1: Opening, as intro builds, brushed cymbals and sitar less texture and less audible. Guitar slightly thicker sounding, violins a little more body but less texture.

Vishwar Mohan Bhatt / Ry Cooder, A meeting by the river: Subtle differences. I get the sense that the Mojo is slightly brushing over the tonal contrasts and subtle pitch and amplitude variations in the worked strings. Crossfeed is brilliant here.

David Sylvian, Secrets of the beehive, When Poets dream of angels: Opening, less air and more fullness in guitars. Voice has more body, less texture. Voice and strings, both give impression of reduced modulation.

The Orb, No sounds are out of bounds, The end of the end: Sounds in lower mids with amplitude modulation seem somewhat compressed, like the sounds occupy a smaller dynamic range within the mix. Details on voice reverberations less apparent. Less texture, space and air around the top end. More punchy and pacey.

Wolfbane: Intro, bass more emphatically present, but thicker with less detail. Less texture size, height and shape to synthesized vocal crescendo.

Other blue worlds: less texture on top of bass on intro gives darker sound creating narrower space.

Nick Cave and the Bad Seeds, Stagger Lee: Clear improvement in pace and timing. Ramshackle intro beautifully conveyed, epic when it all comes together with the vocal. Livens up the Quad ERA-1 nicely. Captures the visceral nature and drive of the track, very, very big improvement.

Cardiacs, On land and in the sea, The duck and Roger the horse: Smaller stage, obviously bigger macrodynamics, more pace and drive to the rhythm. Comparative loss of texture in sax that lives in top right hand side of the mix. Some congestion through mids.

Eberhard Weber, Sand 24 bit 192KHz: Very very close. Slightly less vibrant, similar texture, atmosphere, snappier sense of timing?

Nursrat Fateh Ali Khan, Mustt Mustt, Fault lines: Opening panned / modulated guitar strum reduced sense of modulation. Voice very similar. Less expansive stage. Lowest bass notes more emphatically presented.

Future sound of London, Lifeforms, Ill flower: Upper mid metallic texture in cascade rendered nearer to white noise. Detail / texture reduced. Texture can't be EQ'd in. Throughout the album, FSOL’s sculpted lower frequency events seem to have reduced spatial and amplitude information resulting in loss of shape and shape changes.

Björk, Vespertine, Undo: Richer bass, slightly more body to voice, reduced detail in mid high atmospherics. Bell sustain audible for less time in busy mix. Multitracked voice less separated.

Pagan Poetry: when things get really busy, separation / resolution of multiple sounds partially blend into one to a greater extent.

Fantasia on a theme by Thomas Tallis (The new queens hall orchestra / Barry Wordsworth): Bowing on higher strings less rendered. More weight in lower strings. Imaging / placement as rest of orchestra comes in similar. Position of each section slightly less well defined?

Listening to Pictures Jon Hassell, Dreaming: Less texture in bass, reduced metallic character in upper mid synth sound. Trumpet through effects not as spacious. Loses atmosphere substantially.

Radiohead, A moon shaped pool, Burn the witch (24 bit 44.1KHz): Less separation of plucked / bowed strings. Much better rythmic cohesion throughout song.

Ok Computer, Subterranean Homesick Alien (24 bit 96KHz): Closer than 44.1KHz material, still some loss of texture and reduced portrayal of dynamic shading.

Thanks for the very impressive detailed review/comparison! May I ask what cable(s) you're using to connect Mojo 2?

 

[ChrisGB]

Thanks for the very impressive detailed review/comparison! May I ask what cable(s) you're using to connect Mojo 2?

For the laptop / phone / M6 / PC, I've tried two different USB C cables and for the PC, two different USB A to USB micro cables. I've also used the M6 in USB DAC mode from the laptop via the same USB C-C cable where it sounds much the same as it does providing it's own digital input, so I am happy that the cables are not a significant factor. The cables are generic, nothing special.

I don't think there is anything wrong with the Mojo 2, it is excellent, but the M6 is punching so far above it's price point in so many ways. The Shanling Windows USB driver is not without issues mind you, but I never had the dropout into white noise with it.

 

[kumar402]

Btw, why is everyone their Mojo 1 sounding "warm"? My Mojo 1 (with the Poly) sounds harsh.

Warm can sound harsh. Warmth comes from mid bass boost and harshness comes from sparkly treble and higher frequency. Warm doesn’t mean smooth and dark. Mojo 1 is warm but has enough energy in treble that if paired with bright IEM it may sound harsh.

 

[kumar402]

Should I splurge for the M2? I'm totally satisfied with the M1 in my current setup and don't see using the M2 EQ.

No. Don’t try to change or fix something that ain’t broken just for the sake of it. After getting M2 you may just end up using bass shelf to sound it like M1

 

[adamjohari]

How do I use the Chord Mojo to connect to my amp? Can I use the 3.5mm to RCA adapter? I saw the Audioquest Hard Mini. This should work right? And what Voltage output should I be using? Thanks in advance.

 

[Rob Watts]

Dear @Rob Watts

How does lossless EQ in Mojo 2 differs from Qudelix 5K parametric EQ and Schiit Loki Mini in term of sound degradation wise?

I can't comment upon individual products, but I can comment upon the technical side of implementations.

64 bit DSP is, in my opinion, inadequate to transparently do EQ. The issue here is with small signals, and with noise floor modulation. With noise floor modulation, floating point implementations create noise floor modulation, and at a level that is audible; this adds an artificial brightness and hardness to the sound.

The issue with small signals is more involved - if the amplitude of small signals changes with respect to large signals (it will be smaller than it should) this will degrade the perception of depth. Moreover, if the phase shift of the small signal is different to large signals this too is audible. Based on lots of listening tests, I have conclude that for small signals to be perfectly reproduced then it must be able to reproduce a -301 dB signal with amplitude accuracy of +/-0.001dB and phase accuracy of +/-0.001 degrees. If it doesn't do that, then it will affect the sound quality and will not be transparent. To do this you need to do 3 things - use a lot more bits than 64 (104 bits in Mojo 2), and use fixed point processing, and use noise shaping on all internal nodes of the DSP at 705/768k or greater. None of the current EQ DSP's do any of these essential things - excepting of course Mojo 2.

For analogue implementations of EQ, you need lots of resistors, capacitors, inductors, contacts, potentiometers, amplifiers and all of these things on their own seriously damages transparency. That's why audiophiles since the 1970's have eschewed using EQ and tone controls.

From a circuit perspective the resistance of the components will alter in temperature, and the engineers will always design equipment with this in mind. As resistance can vary somewhat this could be noticeable, but without knowing the innards of the Mojo it's hard to tell and we'd have to have the engineers themselves tell us. A fairly typical change in resistance for 30C is 10% or so.

Dismissing the youtubers comment offhand suggests a lack of understanding of how circuits work. It's entirely possible from a scientific perspective, but whether those changes are audible is hard to tell. Here's a good discussion.

https://www.superbestaudiofriends.o...be-warmed-up-for-a-while-fact-or-fiction.156/

You are wrong by 1000 times. The critical resistors in Mojo 2 are rated at 10 ppm. That is a 0.01% change in resistance going from 20 deg C to 30 deg C. Moreover, that change would have zero affect upon Mojo's measured and listening performance.

For sure conventional DACs do need warm up time, for a number of complex reasons, and you can see it in the measurements. All the measurements do not change in any detectable manner upon turn on with Mojo 2.

My DACs do not have any significant warm up time, nor do they have a break-in period - any changes to SQ is your brain adjusting to the new sound. As someone posted on the Dave thread recently a 5 year old Dave sounds the same as a new Dave. I achieve this by solving a large number of individual issues, solutions to which gets applied on every DAC I design.

 

[kumar402]

How do I use the Chord Mojo to connect to my amp? Can I use the 3.5mm to RCA adapter? I saw the Audioquest Hard Mini. This should work right? And what Voltage output should I be using? Thanks in advance.

Yes, that will work. Make sure you put Mojo in 2v out using the chart.

 

[Amberlamps]

So, whats the consensus, does mojo 2 walk all over the original mojo ?

I’m really interested in buying one, but only if it kicks mojo’s ass majorly, so whats the verdict ?

 

[Another Audiophile]

So, whats the consensus, does mojo 2 walk all over the original mojo ?

I’m really interested in buying one, but only if it kicks mojo’s ass majorly, so whats the verdict ?

My verdict is simple. Mojo 2 is more dynamic, better controlled bass and higher transparency. Also mojo 1 is one sounding unit while the Mojo 2 can be any sounding unit you want it to be.

 

[jinx20001]

I can't comment upon individual products, but I can comment upon the technical side of implementations.

64 bit DSP is, in my opinion, inadequate to transparently do EQ. The issue here is with small signals, and with noise floor modulation. With noise floor modulation, floating point implementations create noise floor modulation, and at a level that is audible; this adds an artificial brightness and hardness to the sound.

The issue with small signals is more involved - if the amplitude of small signals changes with respect to large signals (it will be smaller than it should) this will degrade the perception of depth. Moreover, if the phase shift of the small signal is different to large signals this too is audible. Based on lots of listening tests, I have conclude that for small signals to be perfectly reproduced then it must be able to reproduce a -301 dB signal with amplitude accuracy of +/-0.001dB and phase accuracy of +/-0.001 degrees. If it doesn't do that, then it will affect the sound quality and will not be transparent. To do this you need to do 3 things - use a lot more bits than 64 (104 bits in Mojo 2), and use fixed point processing, and use noise shaping on all internal nodes of the DSP at 705/768k or greater. None of the current EQ DSP's do any of these essential things - excepting of course Mojo 2.

For analogue implementations of EQ, you need lots of resistors, capacitors, inductors, contacts, potentiometers, amplifiers and all of these things on their own seriously damages transparency. That's why audiophiles since the 1970's have eschewed using EQ and tone controls.



You are wrong by 1000 times. The critical resistors in Mojo 2 are rated at 10 ppm. That is a 0.01% change in resistance going from 20 deg C to 30 deg C. Moreover, that change would have zero affect upon Mojo's measured and listening performance.

For sure conventional DACs do need warm up time, for a number of complex reasons, and you can see it in the measurements. All the measurements do not change in any detectable manner upon turn on with Mojo 2.

My DACs do not have any significant warm up time, nor do they have a break-in period - any changes to SQ is your brain adjusting to the new sound. As someone posted on the Dave thread recently a 5 year old Dave sounds the same as a new Dave. I achieve this by solving a large number of individual issues, solutions to which gets applied on every DAC I design.

Great reply and response, good to see you are active on these forums and willing to engage even though it likely takes valuable time so thanks for that.

Would you have any input on the white noise issue many members are having with the mojo 2?

It has only happened to me once In the week or so I've owned it but it was pretty extreme and loud and could only be solved with a switch off and on of the mojo 2. It does not seem to matter what other hardware people are using, I use a PC, some use apple devices, many varying headsets and earphones but many of us have encountered the same issue, something seems to trigger the mojo 2 and cause only white noise output, for me I was listening to music on my pc with the mojo 2 in desktop mode ( maybe this is where the problem occurs, not seen any reports of it happening in mobile mode ), I simply opened up my emails while listening to music and that seemed to be the trigger, the white noise would stop when i paused the audio but continue when unpaused, as I say the solution was a restart of mojo.

Seems to be quite a big issue with the mojo 2 unit itself I'm hoping can be a driver fix.

Thanks for any reply and I'm sure I speak for everyone here when I say we appreciate your responses and we love the products.

Best regards.

 

[Kentajalli]

From a circuit perspective the resistance of the components will alter in temperature, and the engineers will always design equipment with this in mind. As resistance can vary somewhat this could be noticeable, but without knowing the innards of the Mojo it's hard to tell and we'd have to have the engineers themselves tell us. A fairly typical change in resistance for 30C is 10% or so.

Dismissing the youtubers comment offhand suggests a lack of understanding of how circuits work. It's entirely possible from a scientific perspective, but whether those changes are audible is hard to tell. Here's a good discussion.

https://www.superbestaudiofriends.o...be-warmed-up-for-a-while-fact-or-fiction.156/

@Rob Watts has already answered this, this is just a follow up.
In my draw of components I do indeed have some devices (resistors in particular) rated at 50 ppm - that is 50 part per million for one degree C. So they are widely available, and designers can design circuits that even this low value shouldn't matter, by balancing the topology, say, if one resistor goes down, another would compensate.
I am not familiar with Mojo2 circuit, but Mr. Watts has been proven to be thorough, if I can think of it, he had a solution for it ten years ago.
Consider this, many DACs employed ever more precise clocks, even +1K $ outboard ones, temperature compensated, super clean supplies, expensive cabling to achieve low jitter values - Mr. Watts designs (years ago) irradicated jitter practically.
A simple temperature variation compensation is childs play to the man.

 

[evhvis]

So, whats the consensus, does mojo 2 walk all over the original mojo ?

I’m really interested in buying one, but only if it kicks mojo’s ass majorly, so whats the verdict ?

Depends on the headphones from my testing. The better the headphones the larger the gap is. Headphones with lots of distortion in the bass area don't seem benefit as much from the upgrades. E.g. the HD650 didn't benefit that much (minor improvement), but the Denon AH-D7200 and Focal Elear with Elex pads sounded significantly better on the Mojo 2. Those headphones were the outer edges, but several others were somewhere inbetween in improvement. You basically have to try both in A-B with the headphones/IEMs you plan to use to know if it is a large upgrade or not.

Mojo 2 seems to be more resistant to noise over USB. The difference were larger when running from an iphone instead of optical.

 

[evhvis]

Does anyone know the latency from input to output on the mojo 2 on optical and USB?