Chord Mojo DAC-amp ☆★►FAQ in 3rd post!◄★☆
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damorgue

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Or you could repurpose it as a desktop unit (as it is, in any case, clinically deceased) and get Temple Audio to build a suitable supercap PSU (5V Supercharger)...
Ok, it is obvious that you are frustrated and angry about this, but bear with me while i try to provide a more balanced view on things.
3. If you are using your Mojo solely in desktop mode, it is possible to operate it without the battery. Note that the Mojo was not designed to be operated in this manner, so this is not covered by warranty, but Rob Watts has posted several times that he has now tested this battery-free mode of operation, and can confirm that technically it does work - so this is an option for anyone who has a Mojo that is out of warranty. @damorgue I suggest that you try this option, because it would be a means to identify if you have additional circuit board damage, that complicates the solution to your problems
I did have it connected at my work desktop during the work day sometimes, but I wouldn't consider it desktop mode as in permanently charging and connected to speakers or anything like that. I just considered it charging before the return trip home.

Your suggestions are interesting. It probably won't be useful to me, but it might mean that it still has some value to someone who do not want to use it as a portable unit then? There is a bit of a conflict in your statements though. Can it be used as desktop unit directly without any battery or other modifications? Does it become more sensitive to ripple w/o the battery and thus requires a really expensive 5V source or would any USB charger I have used in the past work?@CJG888 Has someone checked how high the peak powerdraw can get?

I opened mine up a few weeks ago, and there was no visible battery swelling.
I may end up going the other route, but if not, I would still appreaciate if you would be so kind as to opening it again and try to get measurements of the battery. If not for me, then maybe for someone else. The links I posted to hobbyking above seemed promising size-wise and are availible to both EU and US. If we can find one battery which fits the Mojo, this might be useful info to other Mojo users when they encounter a similar fate.
 
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miketlse

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damorgue

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Was in regards to whether a Mojo can work without battery with the same normal USB charger used in the past, or whether one needs to get some other power source. I would have guessed the charger inside charges the battery which in turn powers the circuitsboard, and that the battery thus sort of acts like a filter. The supercapacitor you mentioned, is that something necessary for it to evne run w/o a battery, or necessary for it not to sound crappy because of the lack of battery?

I will attempt to run it from a regular 5V USB charger without the battery shortly. If I understood you correctly, it should run then? (if maybe not with ideal performance caused by ripple in charger)

Hey guys! I recently converted my Mojo into a desktop amp after the battery died!
https://imgur.com/a/RO32L0j
I used it as a desktop amp for about 2 years and the battery took a beating, as expected. It damn near exploded as there was a ton of pressure when I opened it up. Since I use it primarily as a deskop dac, I decided to convert it to be used without the battery entirely. I put in a power supply port on the side to provide a full 7.5V of power (the battery inside is 7.4V). If you don't need the full power and don't want to do any soldering, you can simply open it, remove the battery and power it just from USB, which is usually 5V. This setup has been amazing so far and is much better for my usage. If I ever need to bring it on a plane or something, it can still be powered over USB with a battery, it just won't perform as well with hard to drive headphones
The 7,5V solution connected to where the battery connects would seem like the logical fix to me since it will become a permanent stationary unit anyways.

Thanks everyone, At least this way, it could end up getting a second life. I was prepared to throw it away.
 
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Audiotistic

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miketlse

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Was in regards to whether a Mojo can work without battery with the same normal USB charger used in the past, or whether one needs to get some other power source. I would have guessed the charger inside charges the battery which in turn powers the circuitsboard, and that the battery thus sort of acts like a filter. The supercapacitor you mentioned, is that something necessary for it to evne run w/o a battery, or necessary for it not to sound crappy because of the lack of battery?

I will attempt to run it from a regular 5V USB charger without the battery shortly. If I understood you correctly, it should run then? (if maybe not with ideal performance caused by ripple in charger)


The 7,5V solution connected to where the battery connects would seem like the logical fix to me since it will become a permanent stationary unit anyways.

Thanks everyone, At least this way, it could end up getting a second life. I was prepared to throw it away.
Rob Watts has posted that the Mojo can be operated without a battery, but the battery does add the capability to provide extra current to the dac, to enhance the performance when there are fast music transients.
Only a few Mojo owners have posted about operating without a battery, but they seem to be experiencing no problems so far.
In principle the supercapacitor is providing the same functionality as the battery, to enhance the performance when there are fast music transients (however normally a supercapacitor would respond faster than a battery). I think only one Mojo owner has pioneered this approach, but if there are no issues, then this is an interesting way to push the boundaries.
 
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damorgue

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Neat, thanks, although it worries me a bit that the one pictured has an old manufacturing date. Either way, non-Chord-branded LiPo batteries with similar spec seems to cost less than 10€ at hobbyking available in different sizes, so I will probably go that route if I don't end up selling it as a strictly stationary Mojo.


Rob Watts has posted that the Mojo can be operated without a battery, but the battery does add the capability to provide extra current to the dac, to enhance the performance when there are fast music transients.
Only a few Mojo owners have posted about operating without a battery, but they seem to be experiencing no problems so far.
In principle the supercapacitor is providing the same functionality as the battery, to enhance the performance when there are fast music transients (however normally a supercapacitor would respond faster than a battery). I think only one Mojo owner has pioneered this approach, but if there are no issues, then this is an interesting way to push the boundaries.
Am I oversimplifying it by assuming I could place something like a 12V+ electrolytic capacitor, as big capacitance as I can fit in there in parallell with wires to a 7,5V powersupply. What makes a supercapacitor a supercapacitor?

Edit: BTW, what is the best way to dispose of a badly swollen LiPo? Is it a terrible idea to throw it in the battery bin?
 
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miketlse

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What makes a supercapacitor a supercapacitor?
It is basically a much larger physical size than normal circuit board capacitors, so can hold far more charge than those capacitors.

Batteries and supercapacitors are both solutions to the product design requirement 'Must include a means to store energy, to enable the product to operate'
  • batteries can store enough charge to allow many hours of operation, but do release that charge relatively slowly
  • supercapacitors can store only enough charge (in the case of the TT2) to allow 10s of operation, but do release that charge very quickly
The original TT contained both batteries and capacitors, to ensure both the power baseload was supplied by battery, and the fast transients were supplied by supercapacitor.
In contrast the TT2 is connected to mains power all the time, so the use of batteries adds no value, and the supercapacitors can satisfy the baseload power for up to 10s, plus the very fast musical transients.

It is only my personal design engineering view, but the experience gained with the TT2 should point the way ahead to a future, where desktop only devices use supercapacitors, and mobile devices use batteries (plus supercapacitors if desired).
 
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damorgue

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I opened mine up a few weeks ago, and there was no visible battery swelling.
I am assuming yours is less conical and more rectangular and could be described by height, width and length? Maybe my glorious paint image could be useful in explaining the dimensions



I can sort of see how the aluminium pouches are pushing eachother apart (and it can balance on that side) but the other end looks better, maybe good enough for me to take measurements from? Is it a dumb idea to throw it in the battery bin at my apartment complex? It is made for batteries, but seems reckless judging by videos of LiPo batteries bursting,
 
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Dexter22

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I used to carry an iPhone+Oppo HA2 combo for a long time so I don’t really mind the portability concerns.
But speaking about remote controlling with the phone, could I use the Poly to do that?
Yes. But look at the prices. If u want to feed lossless to mojo while letting another device control it, I think fiio m6, cayin n3 are options under 150 bucks. Poly alone is 400 bucks. Again, when mojo is out of juice may be for another 1 or 2 hours those devicea will have battery for continuing listening on a long trip if it matters.
 
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dakanao

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Or you could repurpose it as a desktop unit (as it is, in any case, clinically deceased) and get Temple Audio to build a suitable supercap PSU (5V Supercharger)...
Would there be a sound quality improvement, when building a suitable supercap in the Mojo, as compared as to running it out of the internal battery?
 
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delancyst

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Yes. But look at the prices. If u want to feed lossless to mojo while letting another device control it, I think fiio m6, cayin n3 are options under 150 bucks. Poly alone is 400 bucks. Again, when mojo is out of juice may be for another 1 or 2 hours those devicea will have battery for continuing listening on a long trip if it matters.
Did you use the iOS Hiby Music app to control the Shanling M0 through Hiby Link?
I couldn't get Hiby Link to work on my iBasso DX220 through Bluetooth with the iPhone.
 
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harpo1

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Yes. But look at the prices. If u want to feed lossless to mojo while letting another device control it, I think fiio m6, cayin n3 are options under 150 bucks. Poly alone is 400 bucks. Again, when mojo is out of juice may be for another 1 or 2 hours those devicea will have battery for continuing listening on a long trip if it matters.
Not sure where your getting your pricing from but the Poly is $700 plus.
 
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miketlse

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Would there be a sound quality improvement, when building a suitable supercap in the Mojo, as compared as to running it out of the internal battery?
I suspect for 99% of most music files, then no.
However for the other 1% of music files, then it is worth pursuing.
Please don't misinterpret this statement, because I am open minded as to the way forward - the as:is Mojo does an excellent job with 99% of music tracks.
Potentially supercapacitors help push the envelope for the remaining 1%.
You will have to believe me that Chord do read your posts, and consider these proposals for future product improvements.
 
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greenkiwi

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@damorgue I see you've seen the super cap comments above, I think there was a link to a part further back too.

At the very least, I'd fire it up directly from USB to see if there are any other issues, to see whether it's worth swapping batteries. Good luck.
 
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Dexter22

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Not sure where your getting your pricing from but the Poly is $700 plus.
Sorry about the pricing. I meant only above 400 , For what its doing, i only meant its heavenly overpriced.if a wireless source is all u need. of course its not as neat as the poly but insanely cost effective in comparison. Anyway, I never fancied getting one so sorry about false info.
 
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