Chord Mojo(1) DAC-amp ☆★►FAQ in 3rd post!◄★☆
Jul 31, 2019 at 5:50 PM Post #38,986 of 42,765
My condolences.

I love Chord but feel the desktop solution at the $1k mark or below is missing in the lineup.

I found an open box RME ADI-2 DAC a few weeks ago at a good enough price to try and it's an immense upgrade to a Mojo or Hugo 1, as much as I've enjoyed the Mojo and Hugo 1 it's a "hearing your music for the first time again" kind of detail difference. I'll just stick to the RME for a few years and see if Chord wants to compete in the reasonably priced desktop category. I'm sure the Qutest and a good HPA is at the same level and possibly better, but that's too many boxes and too much money just to get rid of the battery power.

Thanks for the recommendation. I will definitely check out the RME ADI-2!

I totally agree that Chord needs a good standalone DAC that competes in the $500 - 1k range! No more batteries for me!
 
Jul 31, 2019 at 6:35 PM Post #38,987 of 42,765
Hello! Assistance is required, the ATSAM3UCB-AU microcontroller, which is responsible for the usb connection, burned down (burned due to self-unscrewing of the screws holding the board and the closing of these controller legs). Need firmware from the working body, dump the flash area and the eeprom area
 
Jul 31, 2019 at 9:04 PM Post #38,988 of 42,765
Thanks for the recommendation. I will definitely check out the RME ADI-2!

I totally agree that Chord needs a good standalone DAC that competes in the $500 - 1k range! No more batteries for me!

Have you tried your Mojo without the battery and plugged in? As a desktop dac that may work and it hours the pressure from th swollen battery, your Mojo may sound ok.
 
Jul 31, 2019 at 10:16 PM Post #38,989 of 42,765


I figured out kinda what was wrong. The battery swelled and appears to have damaged something on the board (will dispose of the battery properly). Chord already graciously replaced my first Mojo (same problem). I am going to call this a loss and move onto something else. I don't think the Mojo battery could handle being a dedicated computer DAC. I did not have the money for the Hugo so I attempted to make the Mojo my dedicated DAC. I don't think the battery could take it.

My mojo needed a battery replacement but it's out of warranty so instead of buying my friends mojo that's up for sale I decided to grab a dragonfly cobalt for portable use, I don't have to worry about batteries and charging that way.
 
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Jul 31, 2019 at 11:07 PM Post #38,990 of 42,765
My mojo needed a battery replacement but it's out of warranty so instead of buying my friends mojo that's up for sale I decided to grab a dragonfly cobalt for portable use, I don't have to worry about batteries and charging that way.

How does it sound?

BTW, you can get a battery in the US for $75 shipped, and the replacement is easy.
 
Jul 31, 2019 at 11:15 PM Post #38,991 of 42,765
On a serious note, how frequent is the battery swelling? I know that problems are more frequently reported on online forums than none, However, I'm curious if there is an actual percentage failure. Thanks.
 
Jul 31, 2019 at 11:19 PM Post #38,992 of 42,765
On a serious note, how frequent is the battery swelling? I know that problems are more frequently reported on online forums than none, However, I'm curious if there is an actual percentage failure. Thanks.

I think the swelling occurs when people play and charge from red often, it will get quite hot this way and the battery will start to swell after being hot for long periods of time. Batteries don't like being hot or cold so it's best to try to keep them close to room temperature for maximum capacity and overall health. Many people won't know unless they open their Mojo.
 
Jul 31, 2019 at 11:25 PM Post #38,993 of 42,765
How does it sound?

BTW, you can get a battery in the US for $75 shipped, and the replacement is easy.

I was surprised how good it sounds coming straight from Mojo, Its too early to say if i think it's better just yet.

I could have purchased a new battery that's true but I've owned one since launch and I just wanted a change, also feels good not having to charge an extra device most nights, you can just pick up and go anytime and also don't need to worry about battery running out when your really enjoying the music.
 
Aug 1, 2019 at 3:46 AM Post #38,994 of 42,765
I think the swelling occurs when people play and charge from red often, it will get quite hot this way and the battery will start to swell after being hot for long periods of time. Batteries don't like being hot or cold so it's best to try to keep them close to room temperature for maximum capacity and overall health. Many people won't know unless they open their Mojo.

Not just heat, but the simple fact that it's plugged in for extended periods of time and topped up above 4.10V per cel consistently is very stressful for any lithium battery. Hugo2's desktop mode avoids this. And I'm not talking about dangerous overcharging above 4.20 V per cel.
 
Aug 1, 2019 at 4:21 AM Post #38,996 of 42,765
I don't find the charging separate from listening to be much of an annoyance, it's more a feeling of "why am I cycling a (-n expensive) battery with limited lifespan when 99% of my listening takes place in the quiet of my home?".

I used to buy "because battery power sounds better", but along came the RME and showed me that all of my past devices that sounded bad form a SMPS were poorly engineered, it's not off the wall power that is the problem. The RMEs stand out quality vs the Mojo and Hugo is precisely less noise and distortion, from a SMPS. And seeing that the Qutest measures better still means that Chord sits on all the pieces needed to make a truly excellent Mojo 2 TT equivalent with SMPS, should they choose to go that route. I would be very excited about such a product.
 
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Aug 1, 2019 at 5:15 AM Post #38,997 of 42,765
On a serious note, how frequent is the battery swelling? I know that problems are more frequently reported on online forums than none, However, I'm curious if there is an actual percentage failure. Thanks.
Chord have shipped 100,000+ Mojos so the current percentage failure rate will still be low.
Read the early posts on this thread, and I think it becomes clear that Chord had requested the battery manufacturer to design/supply a battery that had a predicted design life of 10 years.
At the time I expected that to mean that there should be few, if any, battery failures for many years, so I was surprised when the posts about swollen batteries started to appear after so few years.
I can only assume that the battery manufacturers predictive life model, does not 100% accurately match the use cases of all Mojo owners.

Over the 3+ years lifetime of this thread, some suggestions for minimizing the risk factors have evolved, including post #38994.
Charging from red, and listening at the same time will maximise the temperature, so try and avoid this use case.
 
Aug 1, 2019 at 7:28 AM Post #38,998 of 42,765
I can only assume that the battery manufacturers predictive life model, does not 100% accurately match the use cases of all Mojo owners.

I work for a company that's into battery development and testing for cars, and I can confirm that the industry is still learning about the aging charcteristics of batteries.
Standard testing was for loss of capacity over cycles under controlled conditions and different temperatures, and this number of cycles was stated as battery life.
These tests are done rather fast, say with 1C charge/discharge, so a 1000 cycles would be less than 2 months continuous testing.

Experience has now shown that exposing LiPo batteries to elevated temperatures can decrease their lifetime significantly, independent from cycles.
That's why car batteries now are conditioned to moderate temperatures even when the car is parked. In winter they are heated, in summer they are cooled.

Considering that the Mojo gets pretty warm when permanently charged and used, this would be an explanation for premature aging of the battery.
 
Aug 1, 2019 at 8:00 AM Post #38,999 of 42,765
Chord have shipped 100,000+ Mojos so the current percentage failure rate will still be low.
Read the early posts on this thread, and I think it becomes clear that Chord had requested the battery manufacturer to design/supply a battery that had a predicted design life of 10 years.
At the time I expected that to mean that there should be few, if any, battery failures for many years, so I was surprised when the posts about swollen batteries started to appear after so few years.
I can only assume that the battery manufacturers predictive life model, does not 100% accurately match the use cases of all Mojo owners.

Over the 3+ years lifetime of this thread, some suggestions for minimizing the risk factors have evolved, including post #38994.
Charging from red, and listening at the same time will maximise the temperature, so try and avoid this use case.

Thanks. I read most of not all the thread. I use the poly some days for a few hours as a desktop setup. Some days I use it as a dlna server. And often I use it as a portable Roon endpoint. When it’s dlna server or on the desktop, I usually plug it in at yellow.

I was more reaching for a percentage of failure “in the wild”. There’s probably a higher concentration of failure reports on this thread.
 
Aug 1, 2019 at 8:22 AM Post #39,000 of 42,765
Good day everyone,
I'm thinking of upgrading my DragonFly Red and a used Mojo is the only sub-$500 AMP/DAC that I can think of.
Can any give me a comparison between these units? Sound differences? I'm hoping to get a wider soundstage and more bass physicality with an upgrade.

It's either the Mojo or ALO CV5, which would cost more..

Thanks!
 

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