Chord Mojo(1) DAC-amp ☆★►FAQ in 3rd post!◄★☆
Dec 4, 2015 at 9:49 PM Post #6,258 of 42,765
Why do the higher end DAC's always use FPGA's? And whose design are they loading onto the FPGA? If it's their own then why not just make an ASIC out of it and sell it like the other brands do? All those Sabre's and etc are just FPGA's turned ASIC's for mass production.
 
It always makes it look fishy to me. Has anyone done double blind experiments on a $200 DAC vs. a $600 one? They all seem to have slightly differing sound signatures but in a double blind experiment I'm curious if audiophiles would consistently prefer the $600 one.
 
Dec 4, 2015 at 9:57 PM Post #6,259 of 42,765
Why do the higher end DAC's always use FPGA's? And whose design are they loading onto the FPGA? If it's their own then why not just make an ASIC out of it and sell it like the other brands do? All those Sabre's and etc are just FPGA's turned ASIC's for mass production.

It always makes it look fishy to me. Has anyone done double blind experiments on a $200 DAC vs. a $600 one? They all seem to have slightly differing sound signatures but in a double blind experiment I'm curious if audiophiles would consistently prefer the $600 one.


Not exactly an answer to your question but there may be some hints in Rob's post here:

http://www.head-fi.org/t/784602/chord-mojo-the-official-thread-read-the-first-post-for-updated-info/5745#post_121023


.....But by running the noise shaper at much faster rates you solve this problem too - indeed Mojo noise shapers exceed 200dB THD and noise digital performance - that's a thousand times more resolving power than high end DAC's.

If I get time today I hope to publish noise floor modulation measurements showing Mojo has zero measured noise floor modulation. This level of performance does not happen on any other non pulse array DAC's at any price, and its the primary reason why Mojo sounds so smooth and musical
.
 
Dec 4, 2015 at 10:01 PM Post #6,260 of 42,765
Why do the higher end DAC's always use FPGA's? And whose design are they loading onto the FPGA? If it's their own then why not just make an ASIC out of it and sell it like the other brands do? All those Sabre's and etc are just FPGA's turned ASIC's for mass production.

It always makes it look fishy to me. Has anyone done double blind experiments on a $200 DAC vs. a $600 one? They all seem to have slightly differing sound signatures but in a double blind experiment I'm curious if audiophiles would consistently prefer the $600 one.


Mass production is the key.

Fabbing a chip is not trivial. Even simple ASICs are only cost effective if you are able to sell them in mass quantities. And by "mass" I don't mean a few tens of thousands.

The production quantities required to do this are likely several times the combined sales of all vendors currently using FPGAs either as DACs, filters, both ... or even including additional functionality on the array (e.g. USB, SP/DIF etc.).

Also, some vendors, for example Linn (who use FPGAs for their filter implementations etc.) revise and upgrade their FPGA configuration over time. In fact there are constant discussions about which version of Linn's DS software sounds better.
 
Dec 4, 2015 at 10:02 PM Post #6,261 of 42,765
Has anyone compared between the Mojo & the X7?
I am looking to purchase either one.
 
The only reason why I am holding back on the mojo is because I very much prefer portability.
To me a stack is not as portable as a single box solution.
 
I will be using it mostly for Spotify and Tidal and using it with my SE846 and Sony ZX1.
 
Therefore, if the sq of the mojo is not a significant upgrade over the x7, I might just end up getting the x7 instead.
 
Thanks!
 
Dec 4, 2015 at 10:15 PM Post #6,262 of 42,765
Has anyone compared between the Mojo & the X7?
I am looking to purchase either one.

The only reason why I am holding back on the mojo is because I very much prefer portability.
To me a stack is not as portable as a single box solution.

I will be using it mostly for Spotify and Tidal and using it with my SE846 and Sony ZX1.

Therefore, if the sq of the mojo is not a significant upgrade over the x7, I might just end up getting the x7 instead.

Thanks!


I agree with what ClieOS replied to the same question you posted in the X7 thread. However, I don't agree with his assessment that the more texture and definition is slight, and I consider it not as trivial as he implies. The resolving strength of the DAC is its one purpose and for that the Mojo wins, hands down. The other thing is the Mojo's headphone output is much cleaner and less coloured than the amp module(s) attached to the X7. By this I mean the signal is more representative of the analogue output from the DAC because with the Mojo it strictly is the analogue output of the DAC.... no extra amps in the way. Read the link I just posted above.

The X7 has a wider sound stage, but some may think it's too wide and holographic. I don't think it goes that far but I do prefer the Mojo's presentation more. To me the Mojo sounds more like a live performance and the X7 sounds like I'm listening at the mixing board where each note is more unnaturally separated out but at the same time, in comparison, not as natural, slightly forced. Some people love this. YMMV.

The X7 is great, and performs very well, especially for its price, but to my ears isn't as good as the Mojo. There really are two things to consider here. 1). The Mojo needs a source and the X7 does not. 2). The Mojo can drive a vast range of headphones, the X7 requires different amp modules to perform best with different headphones / IEMs. Each of these units will be a good purchase, you just need to figure out what your needs are.
 
Dec 4, 2015 at 10:24 PM Post #6,263 of 42,765
The Mojo has very, very good layering and a flowing natural sound that does well to mimic what live sound is like. As Relic mentions, the notes are not forced they rise and decay as part of the musical landscape and engross you in the event so that many times, you are part of it. 
 
Dec 4, 2015 at 10:27 PM Post #6,264 of 42,765
Why do the higher end DAC's always use FPGA's? And whose design are they loading onto the FPGA? If it's their own then why not just make an ASIC out of it and sell it like the other brands do? All those Sabre's and etc are just FPGA's turned ASIC's for mass production.

It always makes it look fishy to me. Has anyone done double blind experiments on a $200 DAC vs. a $600 one? They all seem to have slightly differing sound signatures but in a double blind experiment I'm curious if audiophiles would consistently prefer the $600 one.


The same question could have been asked of Apple back in 1985 with the Macintosh. Why didn't Apple license the software to third party computer makers instead of allowing Microsoft to steal it for Windows? It is not just Rob Watts brilliant FPGA programming but the implementation with the amplifier that makes the Mojo sing. If you want a Rob Watts FPGA or the Apple OS you have to buy the Chord or Apple device as the case may be.
 
Dec 4, 2015 at 11:12 PM Post #6,266 of 42,765
Plus it's not just the FPGA filtering but the pulse array DACs as well. Also, the analogue stage. The system as whole has been designed in one house with some very special and complex filters and algorithms to work with the hardware from input to output. You can't get that without doing the entire design from scratch.
 
Dec 5, 2015 at 12:44 AM Post #6,267 of 42,765
Plus it's not just the FPGA filtering but the pulse array DACs as well. Also, the analogue stage. The system as whole has been designed in one house with some very special and complex filters and algorithms to work with the hardware from input to output. You can't get that without doing the entire design from scratch.


Yes, read Rob's posts. Better yet, just listen and compare. It's not subtle and I was quite surprised. Mojo is pretty awesome, compared to almost anything else.
 
Dec 5, 2015 at 12:56 AM Post #6,268 of 42,765
Yes, read Rob's posts. Better yet, just listen and compare. It's not subtle and I was quite surprised. Mojo is pretty awesome, compared to almost anything else.


True, but not all have the luxury. :)
 
Dec 5, 2015 at 3:09 AM Post #6,270 of 42,765
I have the same issue with the m8. Mojo doesn't seem to be supported natively. I have found that you need to use uapp with the screen permanently left on and set the option 'one packet per transfer' otherwise there are is a wierd crackling sound..

It doesn't happen on my nvidia shield tablet (where the mojo seems to integrate well and allow Spotify and native tidal support).

I suspect this means it is an m8 specific issue. Hopefully marshmallow will fix it?

Ade



Hi guys, newbie here need some help. I am using the HTC one M8 phone to pair with Mojo. The phone is stock Lollipop rom 5.0, I am not getting native USB audio out when it paired with the Mojo. Basically, I need to use either Onkyo HF player or UAPP to play my songs. Even worse, I am getting random clicking or shudder noise every 1 or 2 minutes which is not there when using the headphone out. Mojo is fine with PC or MAC. So it is the problem of the phone. I wonder if anybody use M8 here? Any suggestions?
 

Users who are viewing this thread

Back
Top