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Review and Measurements of Chord Mojo DAC and Amp

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Update: After removing the battery, irony struck - my mobile Mojo is now a decent desktop dec/amp.
First - it doesn't randomly shut down anymore. No clue how / why.
It doesn't heat anymore - barely warm. And the hissing stops a few minutes after I turn it on.
Yeah - who knew??? I find it comic- but now I am happy again with this DAC/AMP.
At least I have something that functions properly. I should have tried this 1 year ago and spare myself all the headaches.
 
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I seem to recall charging current was a good source of heat.
Correct! And a battery cramped on top of a hot chip would obstruct any airflow... Whatever the reasons were for the shutdowns - they are gone.
I'd guess some sort of overheating? Who knows? It still leaves me with a bad taste after spending 530$. At least I have something that works now. Knock on wood.
 

Jorj

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Update: After removing the battery, irony struck - my mobile Mojo is now a decent desktop dec/amp.
First - it doesn't randomly shut down anymore. No clue how / why.
It doesn't heat anymore - barely warm. And the hissing stops a few minutes after I turn it on.
Yeah - who knew??? I find it comic- but now I am happy again with this DAC/AMP.
At least I have something that functions properly. I should have tried this 1 year ago and spare myself all the headaches.
I wonder if a replacement battery would have the same issues? I suppose it is possible that a poorly performing\hotspotting battery was the cause of all your Mojo woes.

I'm thinking about ordering one of those batteries I linked previously to just in case they stop selling them. I'm curious to know how the quality is.
 
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I wonder if a replacement battery would have the same issues? I suppose it is possible that a poorly performing\hotspotting battery was the cause of all your Mojo woes.

I'm thinking about ordering one of those batteries I linked previously to just in case they stop selling them. I'm curious to know how the quality is.
The Mojo isn't a mainstream electronic hence I imagine there is one producer of such batteries in China. I'd say the battery should be fine. As for my Mojo - since I use it as a desktop dac I don't feel like trying another battery. Enough headaches :)
 
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In my experience the 'overheat' shutdown would only ever happen whilst charging and playing at the same time, basically the combination of the FPGA heat and the battery charging heat.
If I unplug the charger it would never shutdown, or even get very warm, even on hot summer days.
Since I only use this as a desktop DAC my solution in the end was just to use a timer switch on the USB charger, I have this set to come on a few hours in the middle of the night when I'm not using it.
Interesting that the you say the hissing stopped after a few minutes though, perhaps I need to reinvestgate this...
 
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mojocap.jpg
Here's my Mojo with supercapacitors. They fit juuust right, can't comment on sound because by the time I got this modded (by someone else who knows what they're doing), I hadn't been listening to it for a long time due to overheating battery (which turned out to be dangerously close to bursting out, check out your battery if it's getting too hot peeps!). It's operating normally and really cool for a year or so now, can still be used portably or transportably with an external power bank.

Caveat: they're not enough to supply power for the line out mode so you want to either make yourself a bigger case or go nude to fit bigger caps if you're using Mojo with an amp.
 

Veri

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Caveat: they're not enough to supply power for the line out mode so you want to either make yourself a bigger case or go nude to fit bigger caps if you're using Mojo with an amp.
So besides that negative what are the positives :p
 
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So besides that negative what are the positives :p
Well it runs cool now, and I don't have to worry about the battery exploding out of its case anymore since I'm using the thing exclusively as a desktop DAC for my IEMs without extra amp. :p

Got a Massdrop 789 here and for easy to drive phones, I feel like adding a new source of distortion to the chain, however small, is not really beneficial.
 
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Jorj

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You've piqued my interest with these mods. Can you tell me more? Is this now strictly for desktop use? What about those who run the Mojo sans battery minus the supercapacitors? What is the advantage here?
 
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Can't tell you anything technical as this is more like a fun curiosity project (inspired by Hugo TT) and I don't have the technical background, but apparently with supercaps, it can handle the load when it needs a sudden burst of power or something? Not sure, it may even actually do nothing lol

You can still take it with you on the go but you'll need to lug around a power bank, it works exactly like normal besides that addition (on desktop I've got it connected 24/7 to a charger or a power bank connected to a charger, which somehow helps with the ground hum). As for technical stuff, you'd want to ask the modder who did mine, he's a local modder in my country. I think he mentioned he reused Mojo's battery circuit or something.
 
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The Red is coming for review so we will have that data too.
Hello! I'm not sure if you've received my email, but I was told that after you review the Red, you could send it to me? A guy on Reddit who said he sent it to you said in a giveaway that he'd like to send it to me. I looked at your 'gear pending review' list and didn't see the Red on there, have you already reviewed it and posted it or am I missing something? I'm new to your site and still trying to figure out how it works, thank you so much.
 

Jorj

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Can't tell you anything technical as this is more like a fun curiosity project (inspired by Hugo TT) and I don't have the technical background, but apparently with supercaps, it can handle the load when it needs a sudden burst of power or something? Not sure, it may even actually do nothing lol

You can still take it with you on the go but you'll need to lug around a power bank, it works exactly like normal besides that addition (on desktop I've got it connected 24/7 to a charger or a power bank connected to a charger, which somehow helps with the ground hum). As for technical stuff, you'd want to ask the modder who did mine, he's a local modder in my country. I think he mentioned he reused Mojo's battery circuit or something.
OK, so you have just floated the first pics I've seen of a Mojo TT. :) Nice!

Any contact info for your modder buddy, maybe a website? I'm dying to pick your brain about why a supercap was used instead of just plan-old caps, given an apparent need for stiffening the 5V power supply to the Mojo during current swings.
 

amirm

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Hello! I'm not sure if you've received my email, but I was told that after you review the Red, you could send it to me? A guy on Reddit who said he sent it to you said in a giveaway that he'd like to send it to me. I looked at your 'gear pending review' list and didn't see the Red on there, have you already reviewed it and posted it or am I missing something? I'm new to your site and still trying to figure out how it works, thank you so much.
I actually have two of them for review now. :) After the review is done I will check with the owner to see where he wants me to send it.

My pending list is no longer updated unfortunately. Sorry about that.
 
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I actually have two of them for review now. :) After the review is done I will check with the owner to see where he wants me to send it.

My pending list is no longer updated unfortunately. Sorry about that.

Thanks mate, I saw you received it a while ago and was worried that he hadn't sent it to you at all. Thank you so much. I can't wait to receive the DAC. Do you happen to use Reddit at all, or is this your main forum you use? I love your reviews but haven't found them on Reddit at all.
 

amirm

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I can't wait to receive the DAC. Do you happen to use Reddit at all, or is this your main forum you use?
This is of course where I hang out. I occasionally go and post on reddit/headphones but mostly, what goes on reddit is someone crossposting my reviews there (which I appreciate).
 

Wombat

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Is it not considered poor form around here for vendors to trash other vendors products? Looks like we are seeing a pattern here. At least Chord actually designs their own products.
I see another pattern, here.
 

Wombat

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I see this:


imagesNOZB2GZ8.jpg
 
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