[audionewbi]

I noticed certain things that I dislike when I pair mojo with headphones like the hd600. the sound is plenty loud but it feels like the sound produced is sucked in and collapsed, not dynamic at all.

 

[rwelles]

@Arpiben the volume required to reach a certain dB level will rely heavily on the mastered volume level of the track. Most modern pop songs may need around 10 clicks less than a well recorded older track mastered at a lower level. Chord can't give a guideline as there are entirely too many variables to weed through for every track and every headphone for every user.

For me, I listen to the ETHER C (22 Om, 92 dB) at 35 clicks from zero on average and I've measured (with a spl meter app from my smartphone - which certainly isn't the most accurate) an average reading of anywhere around 75-80 dB (with peaks from 85-90) with most of my tracks. Some tracks I go up about 5 clicks and some I go down about five clicks, based solely on my listening comfort level.




The JH Angie (17 Ohm impedance, 117 dB) I listen at around 15 clicks from zero which gives me an average level roughly around 80 dB on most tracks. Again, depending on the track's volume I'll adjust the level up or down a couple clicks.




I want to re-iterate that this is with my headphones/IEMs and my ears and comfort level, yours will likely vary. If you are concerned then you should get a spl meter (an actual spl meter, or at least smartphone app) to measure what your output is through the headphones/IEMs. The smartphone app may not be super accurate but it should get you in the ballpark. Just make sure to place the mic right at the IEM nozzle or in a sealed ear cup for the best measurement.

 
 
I've found that I set my Mojo significantly higher when using it with JH custom Angie's. So I've made some crude (but direct) measurements.
 
Source: AudioTest on a Mac Mini sending pink noise at 0.0 dBFS 
 
Measuring: AudioControl CM-20 calibrated mic > iAudioInterface2 > iPad Pro. The mic was as close to the earphone as I could get it without actually touching.
 
Ambient noise was around 35 dB (A Weighted). 
 
At 40 clicks up from 0, I measured less than 80 dB (A Weighted).
 
 

 
I thoroughly cleaned the nozzles on my Angie's before the test.
 
I realize that this is by no means a professional test, but at least I'm doing a direct measurement with calibrated equipment. Estimates by @x RELIC x and @Arpiben were based on theoretical calculations. But my results are very, very different, so I'm wondering what I did wrong...
 
(Hey Guys! If you can see ways I can conduct a more accurate test, PLEASE let me know!!)

 

[Mython]

I noticed certain things that I dislike when I pair mojo with headphones like the hd600. the sound is plenty loud but it feels like the sound produced is sucked in and collapsed, not dynamic at all.

 
 
Are you sure your headphone cable or plug haven't developed a short-circuit?

 

[esm87]

What changes are you looking for?

Nothing, pure query. Maybe as MQA is going to be available at some point, perhaps a release to support it? For such a successful product, any improvement would make it even more desirable I imagine. I dont have a mojo but have tried one. Maybe I will pick one up

 

[Mython]

 

What changes are you looking for?

Nothing, pure query. Maybe as MQA is going to be available at some point, perhaps a release to support it? For such a successful product, any improvement would make it even more desirable I imagine. I dont have a mojo but have tried one. Maybe I will pick one up

 
 
I'm no expert on MQA, so please don't quote me on this, but I'm currently under the impression that the majority of MQA implementation is probably on the transport side of things, although there would (AFAIK) need to be some way of 'calibrating' to take account of the DAC one is using, since the MQA process seeks to minimise colouration at any point in the reproduction chain, in an effort to attain reproduction as close as possible to the original performance.

 

[x RELIC x]

Spoiler: Warning: Spoiler!

I've found that I set my Mojo significantly higher when using it with JH custom Angie's. So I've made some crude (but direct) measurements.

Source: AudioTest on a Mac Mini sending pink noise at 0.0 dBFS 

Measuring: AudioControl CM-20 calibrated mic > iAudioInterface2 > iPad Pro. The mic was as close to the earphone as I could get it without actually touching.

Ambient noise was around 35 dB (A Weighted). 

At 40 clicks up from 0, I measured less than 80 dB (A Weighted).





I thoroughly cleaned the nozzles on my Angie's before the test.

I realize that this is by no means a professional test, but at least I'm doing a direct measurement with calibrated equipment. Estimates by @x RELIC x
 and @Arpiben
 were based on theoretical calculations. But my results are very, very different, so I'm wondering what I did wrong...

(Hey Guys! If you can see ways I can conduct a more accurate test, PLEASE let me know!!)

You need a seal (as much as possible) to get as accurate reading as possible. If I don't cover the ETHER C cup with my hand and the iPhone mic poking through my fingers the readings are about 7-10 dB lower. Same with the Angie, it needs to right against the mic.

I realize using my smartphone isn't calibrated, and far from professional, but if I listened to the Angie at 40 clicks from zero with my music in my setup I'd rip them out of my ears faster than you can say ear damage. I'm happy with the ballpark volume I listen to on my setup with the Angie (15 clicks), and don't feel like it's quiet in the least. Actually, sometimes it feels a bit loud to me.

Given that your ambient room measurements are 35 dB (that's lower than average for a quiet room, but not suspiciously so) then there must be something attenuating the volume in your chain. My ambient room measurements are 40-45 dB late at night when everyone is gone to bed, like 2:00 a.m..

Perhaps your pink noise test track is recorded at a low level, or all your music has a digital preamp applied before reaching the Mojo. I think that as long as the ambient room measurements and your measured Mojo volume correlate somewhat then you should be safe. It's common sense. Look at dB level charts for real world loud noises like traffic noise, jackhammer noise, etc., and if those seem loud then you should be able to judge how loud you are listening with your IEM. 40 clicks from zero would be like standing right next to a jet taking off for me.

 

[Xacxac]

You need a seal (as much as possible) to get as accurate reading as possible. If I don't cover the ETHER C cup with my hand and the iPhone mic poking through my fingers the readings are about 7-10 dB lower. Same with the Angie, it needs to right against the mic.

I realize using my smartphone isn't calibrated, and far from professional, but if I listened to the Angie at 40 clicks from zero with my music in my setup I'd rip them out of my ears faster than you can say ear damage. I'm happy with the ballpark volume I listen to on my setup with the Angie (15 clicks), and don't feel like it's quiet in the least. Actually, sometimes it feels a bit loud to me.

Given that your ambient room measurements are 35 dB (that's lower than average for a quiet room, but not suspiciously so) then there must be something attenuating the volume in your chain. My ambient room measurements are 40-45 dB late at night when everyone is gone to bed, like 2:00 a.m..

Perhaps your pink noise test track is recorded at a low level, or all your music has a digital preamp applied before reaching the Mojo. I think that as long as the ambient room measurements and your measured Mojo volume correlate somewhat then you should be safe. It's common sense. Look at dB level charts for real world loud noises like traffic noise, jackhammer noise, etc., and if those seem loud then you should be able to judge how loud you are listening with your IEM. 40 clicks from zero would be like standing right next to a jet taking off for me.

Despite I don't own Angie, I can confirm this. My not-so-sensitive customs (36 ohm, 110dB) comfortable listening level is 31 clicks from 0. 36 clicks, my ears start to hurt. 40 clicks? :basshead:

 

[gnarlsagan]

Just thought I'd stop in to mention that I've jumped on the Mojo bandwagon. It's probably the one of the cleanest sources I've heard. Got to try it out with the SE846 and the Rockets. Gotta say that the Rockets + Mojo combo is really TOTL. This is coming from a Leckerton UHA760, which will be going up for sale shortly.
 
Seeing as the Mojo I heard wasn't mine, I'll be picking up my own hopefully sooner than later. 
 
Has anyone had any luck trying different materials wedged in between the phone and Mojo to eliminate RF issues? 

 

[rwelles]

I'll try to re-create my crude test over the weekend, after I've figured out a way to get a good seal between the mic and the Angie.
 
You're right, 40 is waaaaay too loud for iems, but I'm usually over 20 clicks. This concerns me. For the interim, I've decided to take some time off from phones and stick with speakers for a few days, with my spl meter in hand. Maybe enjoying my phones so much has thrown off my internal loudness meter. 
 
Just want to help insure that my hearing will last me for a lifetime...

 

[Xacxac]

Just thought I'd stop in to mention that I've jumped on the Mojo bandwagon. It's probably the one of the cleanest sources I've heard. Got to try it out with the SE846 and the Rockets. Gotta say that the Rockets + Mojo combo is really TOTL. This is coming from a Leckerton UHA760, which will be going up for sale shortly.

Seeing as the Mojo I heard wasn't mine, I'll be picking up my own hopefully sooner than later. 

Has anyone had any luck trying different materials wedged in between the phone and Mojo to eliminate RF issues? 

Practically, none so far. Maybe Audioquest Jitterbug but I haven't read much about it here (anyone?). OTOH, any RFI diminishes on certain distance and/or relative position from Mojo; but unless you're happy with (10 cm) stack, it's not practical. I tried to slip my palm between them, it eliminates the RFI. Well, putting pork chop/beef steak in between isn't practical too.

What's your source? Sources have various RF outputs.

 

[SearchOfSub]

Anyone have any experience with VRM spread spectrum? It's supposed to reduce EMI but it sounds worse enabled?

 

[gnarlsagan]

Practically, none so far. Maybe Audioquest Jitterbug but I haven't read much about it here (anyone?). OTOH, any RFI diminishes on certain distance and/or relative position from Mojo; but unless you're happy with (10 cm) stack, it's not practical. I tried to slip my palm between them, it eliminates the RFI. Well, putting pork chop/beef steak in between isn't practical too.

What's your source? Sources have various RF outputs.

 
Source is a Nexus 5 for now, although I haven't used it with a Mojo yet to confirm if RF issues exist. My question is mainly for planning ahead. I checked out some additional info through this link and RFI shielding looks a lot less simple than it would initially seem. Thanks for the feedback.
 
Maybe we could get a list of phones/sources know to cause or not cause RFI? 

 

[Xacxac]

Source is a Nexus 5 for now, although I haven't used it with a Mojo yet to confirm if RF issues exist. My question is mainly for planning ahead. I checked out some additional info through this link and RFI shielding looks a lot less simple than it would initially seem. Thanks for the feedback.

Maybe we could get a list of phones/sources know to cause or not cause RFI? 

You're right, totally eliminating EMI is painful. Sorry I never have any experience with android devices. iPhone 6s outputs minimal EMI, I had it for a week, thanks to EMI shield covering the PCB (search few previous pages). Now I own iPhone SE, really noisy.

The best solution is to visit local audio shop (if any) and try mojo with your phone.

 

[x RELIC x]

Source is a Nexus 5 for now, although I haven't used it with a Mojo yet to confirm if RF issues exist. My question is mainly for planning ahead. I checked out some additional info through this link and RFI shielding looks a lot less simple than it would initially seem. Thanks for the feedback.

Maybe we could get a list of phones/sources know to cause or not cause RFI? 

Anything that receives and transmits a wireless signal will have the potential to cause EMI/RF noise with any device. It's not just limited to the Mojo. I've been reading similar reports for a while with the HA-2, DP-X1, FiiO X7, etc.. I'm not trying to defend the Mojo here, but there needs to be certain expectations when using a portable device in conjunction with a wireless signal. There are so many factors that could be the cause, such as signal strength, frequency band, distance to wireless router/cel tower, internal antennae quality, cable RF rejection/sensitivity, etc..

My iPhone 5S has zero EMI/RF (that I can hear) when on LTE with the Mojo, but as soon as I switch to 3G (or worse 2G) I get a lot of interference. I understand that on it's own the iPhone doesn't cause issues with itself, but it's obviously built with the appropriate internal shielding. Using an external device, no matter the device, all bets are off. Some have found that using a Ferrite core could choke some of the EMI/RF but then again some have reported little success. There is no bullet proof solution for any device except to simply use the smartphone as a standalone unit. As was just recommended the safest bet is to test it in a store before purchasing if possible.

 

[Xacxac]

Anything that receives and transmits a wireless signal will have the potential to cause EMI/RF noise with any device. It's not just limited to the Mojo. I've been reading similar reports for a while with the HA-2, DP-X1, FiiO X7, etc.. I'm not trying to defend the Mojo here, but there needs to be certain expectations when using a portable device in conjunction with a wireless signal. There are so many factors that could be the cause, such as signal strength, frequency band, distance to wireless router/cel tower, internal antennae quality, cable RF rejection/sensitivity, etc..

My iPhone 5S has zero EMI/RF (that I can hear) when on LTE with the Mojo, but as soon as I switch to 3G (or worse 2G) I get a lot of interference. I understand that on it's own the iPhone doesn't cause issues with itself, but it's obviously built with the appropriate internal shielding. Using an external device, no matter the device, all bets are off. Some have found that using a Ferrite core could choke some of the EMI/RF but then again some have reported little success. There is no bullet proof solution for any device except to simply use the smartphone as a standalone unit. As was just recommended the safest bet is to test it in a store before purchasing if possible.

Just want to add: we're living in super-dense RFI space nowadays. Microwave? RMI. Bluetooh mouse? RMI. Wifi router? RMI. Lightning bolt? EMI. Cordless phone? EMI. Technically, totally eliminating EMI is almost impossible. But those EMI waves are inaudible due to strength&distance. The best way to eliminate audible EMI is by putting phone to airplane mode & listen to the music offline.