I'm creating this to answer all the repeat questions in the main Mojo threads.
Q. My Mojo gets noticeably warm while charging and playing music. Is this OK?
Yes. The Mojo uses 1.7W of power, so it will get comfortably warm during use, and has thermal cut-outs that prevent it overheating, even if charged at the same time.
Q. How do I know how much charge is left in the Mojo's battery?
Below the USB charging port is a small light. The colour of this light indicates the battery level. Fully charged is blue, green at 75%, yellow at 50% and red at 25% Flashing red means 10 minutes left.
Q. I hear a sound when the charger I'm using is connected to the charging port. Is this normal?
Short answer: Try a different charger. Longer answer from Rob below. Note that this is a separate issue to the one which affected an early batch of units which were faulty.
Quote:
Charger tested with no noise: Apple travel charger, Anker PowerPort 5
http://www.amazon.co.uk/dp/B00VTI8K9K
Recommended cable: Anker PowerLine, Chord Mojo's bundled cable
http://www.amazon.co.uk/dp/B014H3GKZ4
Q. The volume lights are now different colours. Is something wrong?
No. Below "red-red" the "+" volume button light will stay at brown and the "-" volume light will cycle through the colours of the rainbow again for very low volume levels for highly sensitive IEMs. A similar thing will happen at very high volume levels, with the "-" light staying static and the "+" light cycling through a few colours.
Q. How do I set line-level output?
Any volume level can be used for a line-level output. The Mojo will also remember the previously set volume when powering on. However, you can hold down both volume buttons when powering on to set the volume to a standard output level for typical line-out use.
Q. Is there anyway to bypass the amp on the Mojo but still utilize the DAC? Will the line out function accomplish a bypass?
Q. How do I get line-level output?
There are two ways: Hold down the volume buttons when you switch on to lock the Hugo to line-level output. Be careful not to have headphones plugged in when you do this!
The other way is to set the volume to, say, double-blue to give you 2V of output.
Q. Should I use the volume control on my computer/DAP/digital source or should I use the volume control on the Mojo?
Q. How do I know if the volume control on my computer/DAP is affecting the sound quality?
Q. What's the pinout for the COAX input?
You need a TS or TRS 3.5mm plug with the tip positive and sleeve negative. The ring on a TRS plug would not be connected.
A cheap way to connect a device that uses the same type of TS coax output (such as many Chinese-made DAPs) can be found in this post.
Q. How do I connect a FiiO X5II via coax?
The X5II uses a strange plug arrangement due to it sharing the output with the headphone socket. In the X5, the headphone socket has a TRRS (4-pole) arrangement with the tip and first ring not connected and the sleeve and last ring respectively "+" and "-". You'll either need to use the adaptor with a coax cable, or have a special cable made.
Q. How do I connect an iPhone, iPad or iPod to the Mojo?
If your iDevice can use a Camera Connection Kit (CCK) then you'll need to get the CCK cable from apple which has a USB A socket on one end and use a USB A to micro B cable. You cannot use old scroll-wheel type iPods.
Q. Can I use [this USB adaptor]?
John Franks of Chord doesn't recommend using hard USB adaptors, to avoid putting excessive strain on the USB port.
USB to micro USB port adaptors, such as the one below, don't stick out far enough of the CCK to be reliable.
Q. How do I connect a Sony DAP?
See these posts and the Amazon item mentioned:
www.head-fi.org/t/784602/chord-mojo-the-official-thread/555#post_11999231
www.head-fi.org/t/784602/chord-mojo-the-official-thread/1005#post_12005228
www.amazon.com/gp/product/B00FF086HE?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00
www.head-fi.org/t/784602/chord-mojo-the-official-thread/1035#post_12005341
www.head-fi.org/t/784602/chord-mojo-the-official-thread/1230#post_12008886
www.head-fi.org/t/784602/chord-mojo-the-official-thread/1455#post_12012351
It is recommended to NOT up-sample with any software. The Mojo has a powerful FPGA built-in with programming based on Rob Watts' 30 years of research which he states is far more capable than what any computer software is capable of. It is best to set the output of your computer, phone or player to the same bit rate and sample rate of the music being played. Many audiophile players will automatically do this.
Q. Can the Mojo accept DSD?
Yes, it can over any of the inputs using DSD over PCM (DoP). Your player will need to support this for it to work. DSD music isn't needed for good sound quality with the Mojo.
Q. Do I need a driver for Macs? (OSX)
No. OSX supports high-res PCM playback. You will want to match the output sample rate with the music sample rate. You can set this in Audio Midi Setup. Many "audiophile" players (Audirvana Plus, Amarra, VOX etc.) will auto-switch the sample rate to match the music. You don't want OSX re-sampling the music!
Q. Which driver should I use in Windows? DirectSound, ASIO or WASAPI?
ASIO or WASAPI to avoid Windows mixing in system sounds.
Q. Can I listen to it while it's charging?
Yes. However the charge will take longer than charging with the Mojo powered off.
Q. I saw someone connect their headphones with the left channel plugged into one headphone socket and one plugged into the right socket. They reckoned they were getting balanced output. Is this true?
No. Both headphone sockets are connected to the same output. The Mojo only has a single-ended output.
Q. Why doesn't the Mojo have balanced output?
For the best performance for the design, a single-ended output is best. A balanced output would require double the circuitry and would reduce the objective performance, not increase it. The Mojo can output 5V, which is more than enough to generate up to 120 dB of sound cleanly into most headphones.
Q. Are there independent measurements of the Mojo?
Yes, on Stereophile: http://www.stereophile.com/content/chord-electronics-mojo-da-headphone-amplifier-measurements
And on OhmImage: http://ohm-image.net/data/audio/rmaa-chord-mojo-24-bit
Q. What is the Mojo made out of?
The Mojo is made from aluminum and comes with small rubber feet pre-installed on the bottom.
Q. What do the different colours on the power button refer to?
They represent the output encoding or sample frequency rate it is fed.
Sample frequencies are in KHz.
Power
Q. My Mojo gets noticeably warm while charging and playing music. Is this OK?
Yes. The Mojo uses 1.7W of power, so it will get comfortably warm during use, and has thermal cut-outs that prevent it overheating, even if charged at the same time.
Q. How do I know how much charge is left in the Mojo's battery?
Below the USB charging port is a small light. The colour of this light indicates the battery level. Fully charged is blue, green at 75%, yellow at 50% and red at 25% Flashing red means 10 minutes left.
Q. I hear a sound when the charger I'm using is connected to the charging port. Is this normal?
Short answer: Try a different charger. Longer answer from Rob below. Note that this is a separate issue to the one which affected an early batch of units which were faulty.
Quote:
Charger tested with no noise: Apple travel charger, Anker PowerPort 5
http://www.amazon.co.uk/dp/B00VTI8K9K
Recommended cable: Anker PowerLine, Chord Mojo's bundled cable
http://www.amazon.co.uk/dp/B014H3GKZ4
Volume
Q. The volume lights are now different colours. Is something wrong?
No. Below "red-red" the "+" volume button light will stay at brown and the "-" volume light will cycle through the colours of the rainbow again for very low volume levels for highly sensitive IEMs. A similar thing will happen at very high volume levels, with the "-" light staying static and the "+" light cycling through a few colours.
Q. How do I set line-level output?
Any volume level can be used for a line-level output. The Mojo will also remember the previously set volume when powering on. However, you can hold down both volume buttons when powering on to set the volume to a standard output level for typical line-out use.
Q. Is there anyway to bypass the amp on the Mojo but still utilize the DAC? Will the line out function accomplish a bypass?
Q. How do I get line-level output?
There are two ways: Hold down the volume buttons when you switch on to lock the Hugo to line-level output. Be careful not to have headphones plugged in when you do this!
The other way is to set the volume to, say, double-blue to give you 2V of output.
Q. Should I use the volume control on my computer/DAP/digital source or should I use the volume control on the Mojo?
Q. How do I know if the volume control on my computer/DAP is affecting the sound quality?
Inputs
Q. What's the pinout for the COAX input?
You need a TS or TRS 3.5mm plug with the tip positive and sleeve negative. The ring on a TRS plug would not be connected.
A cheap way to connect a device that uses the same type of TS coax output (such as many Chinese-made DAPs) can be found in this post.
Q. How do I connect a FiiO X5II via coax?
The X5II uses a strange plug arrangement due to it sharing the output with the headphone socket. In the X5, the headphone socket has a TRRS (4-pole) arrangement with the tip and first ring not connected and the sleeve and last ring respectively "+" and "-". You'll either need to use the adaptor with a coax cable, or have a special cable made.
Q. How do I connect an iPhone, iPad or iPod to the Mojo?
If your iDevice can use a Camera Connection Kit (CCK) then you'll need to get the CCK cable from apple which has a USB A socket on one end and use a USB A to micro B cable. You cannot use old scroll-wheel type iPods.
Q. Can I use [this USB adaptor]?
John Franks of Chord doesn't recommend using hard USB adaptors, to avoid putting excessive strain on the USB port.
USB to micro USB port adaptors, such as the one below, don't stick out far enough of the CCK to be reliable.
Q. How do I connect a Sony DAP?
See these posts and the Amazon item mentioned:
www.head-fi.org/t/784602/chord-mojo-the-official-thread/555#post_11999231
www.head-fi.org/t/784602/chord-mojo-the-official-thread/1005#post_12005228
www.amazon.com/gp/product/B00FF086HE?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00
www.head-fi.org/t/784602/chord-mojo-the-official-thread/1035#post_12005341
www.head-fi.org/t/784602/chord-mojo-the-official-thread/1230#post_12008886
www.head-fi.org/t/784602/chord-mojo-the-official-thread/1455#post_12012351
Playing Music
Q. My computer (or phone) has up-sampling built into the player. What should I set it to for best quality?It is recommended to NOT up-sample with any software. The Mojo has a powerful FPGA built-in with programming based on Rob Watts' 30 years of research which he states is far more capable than what any computer software is capable of. It is best to set the output of your computer, phone or player to the same bit rate and sample rate of the music being played. Many audiophile players will automatically do this.
Q. Can the Mojo accept DSD?
Yes, it can over any of the inputs using DSD over PCM (DoP). Your player will need to support this for it to work. DSD music isn't needed for good sound quality with the Mojo.
Q. Do I need a driver for Macs? (OSX)
No. OSX supports high-res PCM playback. You will want to match the output sample rate with the music sample rate. You can set this in Audio Midi Setup. Many "audiophile" players (Audirvana Plus, Amarra, VOX etc.) will auto-switch the sample rate to match the music. You don't want OSX re-sampling the music!
Q. Which driver should I use in Windows? DirectSound, ASIO or WASAPI?
ASIO or WASAPI to avoid Windows mixing in system sounds.
Q. Can I listen to it while it's charging?
Yes. However the charge will take longer than charging with the Mojo powered off.
Misc
Q. I saw someone connect their headphones with the left channel plugged into one headphone socket and one plugged into the right socket. They reckoned they were getting balanced output. Is this true?
No. Both headphone sockets are connected to the same output. The Mojo only has a single-ended output.
Q. Why doesn't the Mojo have balanced output?
For the best performance for the design, a single-ended output is best. A balanced output would require double the circuitry and would reduce the objective performance, not increase it. The Mojo can output 5V, which is more than enough to generate up to 120 dB of sound cleanly into most headphones.
Q. Are there independent measurements of the Mojo?
Yes, on Stereophile: http://www.stereophile.com/content/chord-electronics-mojo-da-headphone-amplifier-measurements
And on OhmImage: http://ohm-image.net/data/audio/rmaa-chord-mojo-24-bit
Q. What is the Mojo made out of?
The Mojo is made from aluminum and comes with small rubber feet pre-installed on the bottom.
Q. What do the different colours on the power button refer to?
They represent the output encoding or sample frequency rate it is fed.
Sample frequencies are in KHz.