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

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Pink Floyd Dark Side of the moon mastered at Abbey Roads studio with Alan Parsons and the gang using every tool at their disposal. There are several versions (compression or lossless) the 24/192 Vinyl rip is awesome.

Just catching up on my 'back issue' reading here
:
 
I agree wholeheatedly re the vinyl rip option -> out of curiosity what kind of equipment did you use to do the DSOM rip? 
 
There are many more variables in that procedure - cartridge, 'table, phono preamp, A/D converter, cables, etc and hence many different possible outcomes quality-wise.
 
I've done this myself several times with progressively better equipment over the years [using the Mo-Fi mastering] and the results were excellent.
 
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x RELIC x

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This topic might be already discussed before but I didn't find one.

Does anyone know the type of rechargeable battery inside Mojo? How many ampere hour is the capacity? What's the maximum watt for charging?

The battery is a Lithium Polymer battery designed specifically only for the Mojo over three years. Chord has said it's using new battery tech (I know Lithium Polymer is not new by itself), but hasn't specifically said what that is besides thermal and lifespan improvements. Indeed they expect it to last 10 years or more.

Your questions specifically about ampere hour and maximum watts has not been revealed, but a full charge is 8.4V.

All relevant information about the battery that is known is in the battery section of the third post, which I just recently read every link and there is no other information available from Chord.
 
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Xacxac

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The battery is a Lithium Polymer battery designed specifically only for the Mojo over three years. Chord has said it's using new battery tech (I know Lithium Polymer is not new by itself), but hasn't specifically said what that is besides thermal and lifespan improvements. Indeed they expect it to last 10 years or more.

Your questions specifically about ampere hour and maximum watts has not been revealed, but a full charge is 8.4V.

All relevant information about the battery that is known is in the battery section of the third post, which I just recently read every link and there is no other information available from Chord.

I read #3 post & there isn't any detailed information about the battery. I'm just curious because I often use external battery pack to charge Mojo on the go.
 
Thanks for your reply!
 
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tracyca

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Mojo, pico slim make for a small powerful stack. Makes my k3003i sing!
 
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x RELIC x

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Mojo, pico slim make for a small powerful stack. Makes my k3003i sing!

Glad you're liking it. I do have to wonder why you are using the Pico slim as the Mojo is much more powerful with a much cleaner signal. Just curious what the Pico Slim brings to the mix for you.
 
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jmills8

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sharon124

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GOOD HINT :

I am use my mojo with iphone(6s). Last evening i just download ONKYO player and turn ON it upsampling option.
Wow great !!!! I found that there were huge improvement in sound quality from my iphone +mojo+se846.Actually sound quality improved both flac and even 192 mp3 as well...

Then i google .. And try to find the reason. Then i found that its not new thing and most audiophiles use that technique to improve sound quality.
From theory i found that to get max sound quality you have to upsample integer multiple of original song sampling frequency. For example if you have cd ripped flacs sampling freq is 44.1 so you have to upsample it to 88.2 or 176.4 to get max sound quality.( actually ONKYO player do it automatically)

Hope this will help our friends!!!!!

Theoretical explanations can found here.

https://www.audioholics.com/audio-technologies/upsampling-vs-oversampling-for-digital-audio

http://www.mlssa.com/pdf/Upsampling-theory-rev-2.pdf
 
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Mython

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GOOD HINT :

I am use my mojo with iphone(6s). Last evening i just download ONKYO player and turn ON it upsampling option.
Wow great !!!! I found that there were huge improvement in sound quality from my iphone +mojo+se846.Actually sound quality improved both flac and even 192 mp3 as well...

Then i google .. And try to find the reason. Then i found that its not new thing and most audiophiles use that technique to improve sound quality.
From theory i found that to get max sound quality you have to upsample integer multiple of original song sampling frequency. For example if you have cd ripped flacs sampling freq is 44.1 so you have to upsample it to 88.2 or 176.4 to get max sound quality.( actually ONKYO player do it automatically)

Hope this will help our friends!!!!!

Theoretical explanations can found here.

https://www.audioholics.com/audio-technologies/upsampling-vs-oversampling-for-digital-audio

http://www.mlssa.com/pdf/Upsampling-theory-rev-2.pdf
 
I would say you should definitely do whatever gives you the most pleasure

 
 
However, the designer of Mojo has discussed upsampling, previously, in the thread:
 
  Converting the original file into DSD or up-sampling is a very bad idea. The rule of thumb is to always maintain the original data as Mojo's processing power is way more complex and capable than any PC or mobile device.
 
DSD as a format has major problems with it; in particular it has two major and serious flaws:
 
1. Timing. The noise shapers used with DSD have severe timing errors. You can see this easily using Verilog simulations. If you use a step change transient (op is zero, then goes high) with a large signal, then do the same with a small signal, then you get major differences in the analogue output - the large signal has no delay, the small signal has a much larger delay. This is simply due to the noise shaper requiring time for the internal integrators to respond to the error. This amplitude related timing error is of the order of micro seconds and is very audible. Whenever there is a timing inaccuracy, the brain has problems making sense of the sound, and perceives the timing error has a softness to the transient; in short timing errors screw up the ability to hear the starting and stopping of notes.
 
2. Small signal accuracy. Noise shapers have problems with very small signals in that the 64 times 1 bit output (DSD 64) does not have enough innate resolution to accurately resolve small signals. What happens when small signals are not properly reproduced? You get a big degradation in the ability to perceive depth information, and this makes the sound flat with no layering of instruments in space. Now there is no limit to how accurate the noise shaper needs to be; with the noise shaper that is with Mojo I have 1000 times more small signal resolution than conventional DAC's - and against DSD 64 its 10,000 times more resolving power. This is why some many users have reported that Mojo has so much better space and sounds more 3D with better layering - and its mostly down to the resolving power of the pulse array noise shaper. This problem of depth perception is unlimited in the sense that to perfectly reproduce depth you need no limit to the resolving power of the noise shaper. 
 
So if you take a PCM signal and convert it to DSD you hear two problems - a softness to the sound, as you can no longer perceive the starting and stopping of notes; and a very flat sound-stage with no layering as the small signals are not reproduced accurately enough, so the brain can't use the very small signals that are used to give depth perception.
 
The second issue in using the transport to up-sample (44.1 to 176.4 say) is that the up-samplers in a PC or mobile device are very crude, with very limited processing power and poor algorithms. This results in timing problems, and like with DSD you can't hear the starting and stopping of notes correctly. These timing problems also screw up the perception of timbre (how bright or dark instruments sound), the pitch reproduction of bass (starting transients of bass lets you follow the bass tune), and of course stereo imagery (left right placement is handled by the brain using timing differences from the ears). Now Mojo has a very advanced algorithm (WTA) that is designed to maximise timing reconstruction (the missing timing information from one sample to the next) and huge processing power to more accurately calculate what the original analogue values are from one sample to the next. Its got 500 times more processing power than normal, and this allows much more accurate reconstruction of the original analogue signal.
 
So the long and the short is don't let the source mess with the signal (except perhaps with a good EQ program) and let Mojo deal with the original data, as Mojo is way more capable.
 
Rob
 
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jmills8

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GOOD HINT :

I am use my mojo with iphone(6s). Last evening i just download ONKYO player and turn ON it upsampling option.
Wow great !!!! I found that there were huge improvement in sound quality from my iphone +mojo+se846.Actually sound quality improved both flac and even 192 mp3 as well...

Then i google .. And try to find the reason. Then i found that its not new thing and most audiophiles use that technique to improve sound quality.
From theory i found that to get max sound quality you have to upsample integer multiple of original song sampling frequency. For example if you have cd ripped flacs sampling freq is 44.1 so you have to upsample it to 88.2 or 176.4 to get max sound quality.( actually ONKYO player do it automatically)

Hope this will help our friends!!!!!

Theoretical explanations can found here.

https://www.audioholics.com/audio-technologies/upsampling-vs-oversampling-for-digital-audio

http://www.mlssa.com/pdf/Upsampling-theory-rev-2.pdf
onkyo unsampling? Where do I go to push unsampling on the Onkyo?
 
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jmills8

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I would say you should definitely do whatever gives you the most pleasure :blink:


However, the designer of Mojo has discussed upsampling, previously, in the thread:
"except perhaps with a good EQ program)" which one ?
 
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GOOD HINT :

I am use my mojo with iphone(6s). Last evening i just download ONKYO player and turn ON it upsampling option.
Wow great !!!! I found that there were huge improvement in sound quality from my iphone +mojo+se846.Actually sound quality improved both flac and even 192 mp3 as well...

Then i google .. And try to find the reason. Then i found that its not new thing and most audiophiles use that technique to improve sound quality.
From theory i found that to get max sound quality you have to upsample integer multiple of original song sampling frequency. For example if you have cd ripped flacs sampling freq is 44.1 so you have to upsample it to 88.2 or 176.4 to get max sound quality.( actually ONKYO player do it automatically)

Hope this will help our friends!!!!!

Theoretical explanations can found here.

https://www.audioholics.com/audio-technologies/upsampling-vs-oversampling-for-digital-audio

http://www.mlssa.com/pdf/Upsampling-theory-rev-2.pdf
i dont believe up sampling will improve sound as the audio data wont change from the sampling method imo
 
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jmills8

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