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Review and Measurements of Chord Mojo DAC and Amp

pkane

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For those that need convincing, same test on battery power.

Now run it through an audio band frequency sweep with a speaker next to it. Let's see if there are any resonant frequencies that multiply the microphonic response or if it's mostly linear :)
 

March Audio

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Now run it through an audio band frequency sweep with a speaker next to it. Let's see if there are any resonant frequencies that multiply the microphonic response or if it's mostly linear :)
For the purpose of?

It will have natural frequencies :) but yes I suppose interesting to show it :)
 
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Thomas savage

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To see if it can really be used as a microphone?
DAC and microphone, the mojo is a bargain.. “ roll up roll up we have a perfect gift for all you digital audio karaoke lovers out there “
 

Jorj

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Forgive my layman's ignorance, but how is this possible? The FPGA handles all the digital stuff, which would be immune to such vibration, and Chord's claim is that there is no analog 'section' of the design....

How did they manage to botch that? I find this as unconscionable as Schiit and their synchronous USB design that you have to pay extra to get rid of with Gen. 5.
 

graz_lag

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Forgive my layman's ignorance, but how is this possible? The FPGA handles all the digital stuff, which would be immune to such vibration, and Chord's claim is that there is no analog 'section' of the design....

How did they manage to botch that? I find this as unconscionable as Schiit and their synchronous USB design that you have to pay extra to get rid of with Gen. 5.
Well Chord claims a lot of things...

This is my second Mojo. The first I had sounded great, but had a hum when the power usb was plugged in. You just had to disconnect and play off battery which had a clean noise floor. I noticed the 2nd one did not have a hum when the usb was plugged in. I didn't notice the microphony of the mojo because I only use it for desktop DAC work. I have a much thinner dac/amp I can take on the go.

The only sad thing here is that they market the Mojo as SOTA and they can't even put in loop isolators and design a portable product that doesn't go up in distortion when you move it.
 

Jorj

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The only sad thing here is that they market the Mojo as SOTA and they can't even put in loop isolators and design a portable product that doesn't go up in distortion when you move it.
If this is a portable device that you'd listen to on the plane, train, automobile or shanks-mare, having audible microphonics is a total failure. Abysmal. I know it tests pretty respectably, but this is another matter entirely, and is completely unacceptable. I own very expensive custom IEMs that I use to exclude ambient noise, and my supposedly SOTA DAC\amp is happily pumping the ambient right on in. Granted, this is a bit of an extreme demonstration (thanks, @March Audio), but still. My respect for Chord had fallen, and is now entirely gone.
 
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If this is a portable device that you'd listen to on the plane, train, automobile or shanks-mare, having audible microphonics is a total failure. Abysmal. I know it tests pretty respectably, but this is another matter entirely, and is completely unacceptable. I own very expensive custom IEMs that I use to exclude ambient noise, and my supposedly SOTA DAC\amp is happily pumping the ambient right on in. Granted, this is a bit of an extreme demonstration (thanks, @March Audio), but still. My respect for Chord had fallen, and is now entirely gone.
Quick question: can you actually hear the taps in the phone output?
 

Jorj

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Quick question: can you actually hear the taps in the phone output?
LOL, I was just digging out my Mojo and my Noble K10's to check it....brb.

--edit--

Nope, not that I can tell. My ears are admittedly not what they once were, but I cannot hear it. Tried pure test tones and some nice quiet sections of well recorded classical. I could hear some transmitted microphonics of the tapping via the headphone cable, but once I properly damped it, there was nothing I could discern.

Nevertheless, this does not excuse the lack of engineering diligence that I expect in a device that costs this much.
 
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LOL, I was just digging out my Mojo and my Noble K10's to check it....brb.

--edit--

Nope, not that I can tell. My ears are admittedly not what they once were, but I cannot hear it. Tried pure test tones and some nice quiet sections of well recorded classical. I could hear some transmitted microphonics of the tapping via the headphone cable, but once I properly damped it, there was nothing I could discern.

Nevertheless, this does not excuse the lack of engineering diligence that I expect in a device that costs this much.
The noise from the microphonics is low from the video from March_Audio. Is it possible that not all Mojos have this?
 

graz_lag

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Nevertheless, this does not excuse the lack of engineering diligence that I expect in a device that costs this much.
Well, we have been fortunate enough not to board on airplanes for which Mr. John Franks, Chief Designer and Managing Director at Chord Electronics, was involved in electronics designing before he founded Chord.
According to some of his interviews, he was greatly influenced by that time, because no mistake was allowed without a perfect fix, no workarounds are accepted.
This also is the philosophy of Chord Electronics.
Don’t accept anything but the very best possible ... :p
 

Jorj

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Could be. Also some Mojos are a couple of years old and may have acquired the microphony over time.
I'm fairly certain you're joking. Electronics are not like my knees, which make all kinds of noises they never used to. I think they need to be re-capped.

Apologies, gang, I take full blame for that one. @Thomas savage, I stand ready to accept my punishment.
 

graz_lag

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I'm fairly certain you're joking. Electronics are not like my knees, which make all kinds of noises they never used to. I think they need to be re-capped.
Well, also the cheese wheels sound better with the aging ... not only your knees or the MOJOs ... :p
Sorry guys in France we love cheeses that sound well ...
the sound of a cheese wheel_a.jpg
the sound of a cheese wheel_a.jpg
 

Thomas savage

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I'm fairly certain you're joking. Electronics are not like my knees, which make all kinds of noises they never used to. I think they need to be re-capped.

Apologies, gang, I take full blame for that one. @Thomas savage, I stand ready to accept my punishment.
Your middle aging decrepitude is punishment enough.
 

Thomas savage

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