[tamtrum]

Two issues:

First:
Did anyone experience a loud volume peak, while connecting sensitive iem/headphone to the M15?
I am afraid that by switching from hard to drive HPs to sensitive/easy to drive HPs and not lowering the source phone's volume, the high volume or loud peak might damage the sensitve HP.

Second:
I did listen to the M15 connected to android phones (s22 ultra, s10, other) via several usb cables (very short and short) and noticably experirnced what seems to be electro magnetic interfernce (noise genersted by the phone)

Please advice

I've had this issue with my m15 + iPhone 12, can hear some static if the m15 gets close enough to the sides of the iPhone 12. I have to experiment with more cables but even when it's connected to my iPad and I place it near my iPhone 12, i still have this issue. Maybe we have bad units where they're not properly sealed.

 

[baskingshark]

Thanks.
Did you ever experienced any loud pop on connecting a sensitive HP or IEM to the M15 while its connected to an operating usb source?

I own a Focal Stellia and would'nt like to threaten it.

Thanks again.

I always mute my dongles/lower it to a very low volume before disconnecting and connecting a new transducer on all dongles, including the M15, just a habit I picked up from stage monitoring over the years.

I have some multi BA high sensitivity/low impedance IEMs and 300+ ohm power hungry gear that I routinely alternate on the M15, and if u don't lower the volume, yes u will get a pop if there is a vast differential volume between the 2.

 

[stormwrx]

I've had this issue with my m15 + iPhone 12, can hear some static if the m15 gets close enough to the sides of the iPhone 12. I have to experiment with more cables but even when it's connected to my iPad and I place it near my iPhone 12, i still have this issue. Maybe we have bad units where they're not properly sealed.

I’m experiencing the same issue when my iPhone is close to the M15. Otherwise, I love the sound.

 

[someyoungguy]

A few observations and impressions on the M15:

It isn't just an M12 with a balanced connection - the 3.5mm on the M15 sounds different than the M12's output. In brief, what I hear is the M15 having a feeling of the sound coming from a blacker, more spacious, background. Another obvious difference is the M15 has more sub-bass than the M12. On bass-heavy tracks it's actually possible to hear that the bass punch or emphasis is also a touch higher on the M12 - still in the sub/lower bass region, but higher up the tonal register than with the M15, where bass goes low and the weight of emphasis is low on the M15. One feature of Questyle's current amplification seems to be the ability to provide fantastic reach and extension at both ends of the frequency spectrum, and with the M15 you can hear the bass disappear right down into the lowest octaves. With my B&W P7s - which already have plenty of bass - the extra emphasis in sub-bass almost borders on too much - almost, as after a few minutes my brain manages to adjust and it doesn't seem overpowering.

The mids and some vocals can feel more forward and obvious on the M12. I think part of this impression is due the M15's extra sub-bass making the mids feel further back. But part of it also seems to come from a difference in attack: the M12's mids and lower treble have a little touch of grain or edge to them, whereas the M15 is a smidge smoother, so that particular details like vocals and guitar work seem more up front on the M12 as that extra edge catches your attention more.

So in total the M15 has a bigger sense of space, blacker background, more sub-bass and touch more smoothness even when comparing like with like in terms of the 3.5mm out from each.

I feel like many people would hear the M15 as a step up, but of course in this hobby it's all subjective and I think some people might even prefer the M12's presentation, where the bass punch or emphasis isn't quite as deep, and the mids and lower treble have more edge, even though the M15 has more space and separation and seems more 'refined', for lack of a better description.

For the balanced output, I hear the same changes that are typically described for balanced vs unbalanced connections on other sources: more separation, sharper outlines to each note or instrument, and bit more definition than the unbalanced connection when playing at the same volume. That doesn't necessarily translate into 'better' though as some people may prefer the 3.5mm sound, depending on synergy with headphones.

Since people have mentioned interference I will say that I've been switching between the M15 and Mojo while testing it's chops, and Mojo has often picked up interference when I heard none from the M15, so the M15 (and M12 for that matter) seem better than Mojo on that front. In general, I haven't really noticed interference with either M12 or M15, but it will depend on your environment obviously.

With both devices the dynamics are fantastic; Questyle seem to be able to bring out not only big dynamic swings of the music as a whole, but also accurate and realistic gradations of dynamics and volume of different instruments playing at the same time.

 

[Questyle]

@tamtrum @stormwrx @zolom I haven't forgotten about you all or this issue The engineers have been testing many M15's across many devices over the last couple days to replicate this issue, but so far we haven't been able to replicate it. I myself have an iPhone 13 Pro, and I've also been testing my M15 to try to replicate this issue, but nothing yet. I'll continue testing, as well as the engineers, and I'll let you know what we come up with. Sorry that you have been experiencing this issue, it's certainly not ideal and we are very sorry about it.

@someyoungguy Nice to meet you, I'm also some young guy Thank you for the detailed analysis here, it's very helpful to other customers and also good feedback for our engineering team! I'll translate and forward this to them

 

[someyoungguy]

@tamtrum @stormwrx @zolom I haven't forgotten about you all or this issue The engineers have been testing many M15's across many devices over the last couple days to replicate this issue, but so far we haven't been able to replicate it. I myself have an iPhone 13 Pro, and I've also been testing my M15 to try to replicate this issue, but nothing yet. I'll continue testing, as well as the engineers, and I'll let you know what we come up with. Sorry that you have been experiencing this issue, it's certainly not ideal and we are very sorry about it.

@someyoungguy Nice to meet you, I'm also some young guy Thank you for the detailed analysis here, it's very helpful to other customers and also good feedback for our engineering team! I'll translate and forward this to them

没事， 很高兴认识你

If you talk to the engineering team, give them a big thanks from me for making great products Have to say it's great being able to interact with the company on here, and seeing the customer service engagement. Keep up the good work!

 

[Questyle]

没事， 很高兴认识你

If you talk to the engineering team, give them a big thanks from me for making great products Have to say it's great being able to interact with the company on here, and seeing the customer service engagement. Keep up the good work!

@someyoungguy 哈哈哈 你是中国人的话 或者中文方便的话 给他们写几句话中文 我直接发到他们私人微信吧

And thank you for the kind words, the least we can do for our loyal customers is to answer their questions and interact with them! Next time you come down to Shenzhen from Shanghai, let me know and you can come visit the offices and lab right in the heart of Shenzhen!

---

@tamtrum @stormwrx @zolom As for you all, I've been listening to the M15 off my iPhone 13 Pro all day these past two days, trying different orientations and such, haven't heard any interference though. If there's a way to capture what you're seeing via video, if at all possible, please do. Perhaps link the M15 to your phone, and then connect the output to a pair of monitors so the camera's microphone can capture the noise/interference. If possible. You can send it to my email address (zach.bielak@questyle.com) whereupon I'll forward it directly to the engineers to help the diagnose the issue.

 

[stormwrx]

@tamtrum @stormwrx @zolom As for you all, I've been listening to the M15 off my iPhone 13 Pro all day these past two days, trying different orientations and such, haven't heard any interference though. If there's a way to capture what you're seeing via video, if at all possible, please do. Perhaps link the M15 to your phone, and then connect the output to a pair of monitors so the camera's microphone can capture the noise/interference. If possible. You can send it to my email address (zach.bielak@questyle.com) whereupon I'll forward it directly to the engineers to help the diagnose the issue.

Thank you! For what it's worth, I switched cables and have not heard any interference the past few days. Will keep you updated if the issue resurfaces! Otherwise, I love the sound.

 

[Questyle]

Ah interesting! @stormwrx what kind/brand of cable were you using before, and which one did you switch to? Good information to tell other customers.

 

[manueljenkin]

Thank you! For what it's worth, I switched cables and have not heard any interference the past few days. Will keep you updated if the issue resurfaces! Otherwise, I love the sound.

The earlier cable might have not had enough shielding I guess. Might be possible to probe and check too.

 

[productred]

EDIT: Problem seems to be resolved, fingers crossed

 

[Questyle]

@productred Was just about to message you here with the updates, but it seems my colleagues beat me to it! In the future, probably the fastest way to hear back from us is info@questyle.com

If anybody else has any recommendations on which are the best off-shelf Type-C to Lighting cables for the M15, please let us know! Always good to hear customer recommendations given how many options there are out there.

 

[someyoungguy]

@someyoungguy 哈哈哈 你是中国人的话 或者中文方便的话 给他们写几句话中文 我直接发到他们私人微信吧

And thank you for the kind words, the least we can do for our loyal customers is to answer their questions and interact with them! Next time you come down to Shenzhen from Shanghai, let me know and you can come visit the offices and lab right in the heart of Shenzhen!

---

@tamtrum @stormwrx @zolom As for you all, I've been listening to the M15 off my iPhone 13 Pro all day these past two days, trying different orientations and such, haven't heard any interference though. If there's a way to capture what you're seeing via video, if at all possible, please do. Perhaps link the M15 to your phone, and then connect the output to a pair of monitors so the camera's microphone can capture the noise/interference. If possible. You can send it to my email address (zach.bielak@questyle.com) whereupon I'll forward it directly to the engineers to help the diagnose the issue.

我的中文不是那么好 Thanks for the offer, I’ll keep it in mind - I still haven’t made it to Shenzhen yet, but travel hasn’t been that easy over the last few years!

Has anyone with the M15 (or M12 for that matter) heard the QPM or earlier iterations like the QP2R? Just wondering how their sound compares.

 

[subguy812]

我的中文不是那么好 Thanks for the offer, I’ll keep it in mind - I still haven’t made it to Shenzhen yet, but travel hasn’t been that easy over the last few years!

Has anyone with the M15 (or M12 for that matter) heard the QPM or earlier iterations like the QP2R? Just wondering how their sound compares.

I always wanted to hear the QPM. I reviewed the QP2R. The QP2R became my reference player 4-5 years ago. The sq is stellar. The M15 is a great dongle, but the QP2R is one stop shopping.

 

[someyoungguy]

I always wanted to hear the QPM. I reviewed the QP2R. The QP2R became my reference player 4-5 years ago. The sq is stellar. The M15 is a great dongle, but the QP2R is one stop shopping.

Interesting. There's a few QPM's going second hand around here for quite reasonble prices (and QP2Rs even cheaper). I'm certainly tempted.

Thanks for the input