[Matpar]

The M15 has a sonic signature owners of Questyle equipment love: strictly neutral [update: essentially uncoloured] with great extension at both ends, unparalleled resolution, clarity, transparency, and crisp dynamics – and all that without ever being strident or aggressive, sterile or analytical (Topping comes to mind). Almost like a little class-A amp in your pocket. If you have listened to the QP1R dap (still the reference of three of us) or the CMA 12 DAC/amp, you will know what I am talking about.

Spatial reconstruction is excellent in both single-ended and balanced circuits. No compromise has been made for the single-ended circuit, the only difference between the two is power. This is in contrast to some other models that sacrifice headroom in their single-ended circuit such as the EarMen Sparrow.

And that’s all you have to know.

More on my blog in a week or so, including comparison to AudioQuest DragonFly Cobalt and the almighty Apogee Groove.

I cannot agree more on basically every word here.

I have just starting using mine, will need some time to "settle", but so far I can say it reminds me a lot of stuff I had in the past that I really liked (from QLS and Aune mainly), without the bulk and limitation that kind of rig involved

The thing that leave me almost speechless is indeed the extension... top is clear and detailed yet never "offending" or sibilant, and bass is so controlled and deep it is making me enjoy again a long forgotten pair of earbuds I have.

It's weird since those are a pair made out of coax cable, hence very "clinical" yet normally a bit "sterile"... well with the M15 they maintain the "almost studio like" performance while having a body and a bass extension I've never reached with other mobile setups.

I will try with more demanding HPs but the combo is so perfect I think I might stop here a while..

Another thing I've noticed, is the PRAT, which to me is just damn right; plus, drums and percussions in general sounds as they should do (I am very picky on this one, and well "trained" by past experiences i.e. with R2R DACs).

Btw, I'm throwing everything at this dongle, from poorly mastered grunge songs, to chamber music, jazz up to Goa trance, and it's a constant surprise so far (better, a confirmation of expectations).

 

[rhart00]

joined the team today with an order for the M15. Have an M12 and love it. Can't wait to hear the M15!

 

[zolom]

Can anyone compare the sound quality and stage between the Questyle M15 and the iFi Go Bar?

Thanks

 

[Otto Motor]

I cannot agree more on basically every word here.

I have just starting using mine, will need some time to "settle", but so far I can say it reminds me a lot of stuff I had in the past that I really liked (from QLS and Aune mainly), without the bulk and limitation that kind of rig involved

The thing that leave me almost speechless is indeed the extension... top is clear and detailed yet never "offending" or sibilant, and bass is so controlled and deep it is making me enjoy again a long forgotten pair of earbuds I have.

It's weird since those are a pair made out of coax cable, hence very "clinical" yet normally a bit "sterile"... well with the M15 they maintain the "almost studio like" performance while having a body and a bass extension I've never reached with other mobile setups.

I will try with more demanding HPs but the combo is so perfect I think I might stop here a while..

Another thing I've noticed, is the PRAT, which to me is just damn right; plus, drums and percussions in general sounds as they should do (I am very picky on this one, and well "trained" by past experiences i.e. with R2R DACs).

Btw, I'm throwing everything at this dongle, from poorly mastered grunge songs, to chamber music, jazz up to Goa trance, and it's a constant surprise so far (better, a confirmation of expectations).

As to PRAT etc. the opposite of the M15 is the Topping L30 imho. Also uncoloured but as dead as a doorknob...with attenuated mids. The L30 measures well but did not satisfy my ears.

 

[manueljenkin]

As to PRAT etc. the opposite of the M15 is the Topping L30 imho. Also uncoloured but as dead as a doorknob...with attenuated mids. The L30 measures well but did not satisfy my ears.

Any idea how the m15 compares to Apogee groove, especially for driving headphones requiring significant current (my srh1540 requires quite a lot of current for full potential). I like the amplifier topology, the analog section implementation of the apogee groove but am not very fond of the sinc interpolator (generally feed a 192khz sample using a spline based interpolator, but it’s not possible to fully bypass the default interpolator beyond that). With the questyle I might have better chance of bypassing it, and also as an added bonus, use Mqa which also does a similar approach to spline based interpolation (probably better). Looking to replace the groove with the questyle but worried about power output and overall fidelity.

 

[Otto Motor]

Any idea how the m15 compares to Apogee groove, especially for driving headphones requiring significant current (my srh1540 requires quite a lot of current for full potential). I like the amplifier topology, the analog section implementation of the apogee groove but am not very fond of the sinc interpolator (generally feed a 192khz sample using a spline based interpolator, but it’s not possible to fully bypass the default interpolator beyond that). With the questyle I might have better chance of bypassing it, and also as an added bonus, use Mqa which also does a similar approach to spline based interpolation (probably better). Looking to replace the groove with the questyle but worried about power output and overall fidelity.

Groove is way more powerful, warmer, and has better spatial reconstruction, most notably stage depth. But it cannot be used with hybrids and does not work with phones. The Groove draws almost four times the M15's current and will run current-hungry headphones with more ease.

I am presently waiting for a balanced cable for my 300 ohm HD 600 to compare with both.

Update: I received the balanced cable...calanced circuit on high gain has more than enough power to driver 300 ohm headphones. Though the Groove has more pizazz because of its higher power.

 

[manueljenkin]

Groove is way more powerful, warmer, and has better spatial reconstruction, most notably stage depth. But it cannot be used with hybrids and does not work with phones. The Groove draws almost four times the M15's current and will run current-hungry headphones with more ease.

I am presently waiting for a balanced cable for my 300 ohm HD 600 to compare with both.

Groove does work with phones but the output will be limited by the transient current supply capability of the phone, and hence generally sounds more controlled on a PC with respect to power.

Anyway, my main target is full size headphones so more clean power is what I desire first and foremost. Let me know how the differential output stacks up in terms of power delivery.

I don’t believe too much in specification numbers of the max power output since topology determines the efficiency of power delivery into the transducer and so it’s hard to compare (best way is to just listen and find out). I’ll have to see if I can find a demo unit to try with my srh1540.

 

[Otto Motor]

Groove does work with phones but the output will be limited by the transient current supply capability of the phone, and hence generally sounds more controlled on a PC with respect to power.

Anyway, my main target is full size headphones so more clean power is what I desire first and foremost. Let me know how the differential output stacks up in terms of power delivery.

I don’t believe too much in specification numbers of the max power output since topology determines the efficiency of power delivery into the transducer and so it’s hard to compare (best way is to just listen and find out). I’ll have to see if I can find a demo unit to try with my srh1540.

OK, Groove may somewhat work with Android phones...but not for long between charges . Kinda pointless. It does not work with iPhone at all as it draws three times the current Apple allows.

 

[noplsestar]

Which Lightning to USB-c cable do you guys use and where have you bought it?

 

[Otto Motor]

Which Lightning to USB-c cable do you guys use and where have you bought it?

This is a very good one: https://oeaudio.shop/products/oeotg-digital-cable?variant=40577134624821

I have this one and a couple of others...they all appear to have the same MFI chip as they all add to the power consumption the same way (compared to the Apple camera adapter).

 

[Questyle]

Does anyone know if trutone is an official distributor? I tried using the message box on Questyle's site but haven't gotten a reply. https://www.trutone.ca/products/view/questyle-m15-mobile-lossless-dac-with-headphone-amplifier Or is there another Canadian retailer?

Just following up here, yes Trutone is indeed an official distributor of ours All good!

 

[Nikola]

Which Lightning to USB-c cable do you guys use and where have you bought it?

I use this cable, works fine: https://www.fiio.com/newsinfo/503267.html

 

[t69p]

I use this cable, works also fine: https://www.aliexpress.com/item/1005004267677420.html?spm=a2g0o.order_list.0.0.43df1802LK4XqA

 

[noplsestar]

Thanks guys for the cable tips!

 

[LakeOfTheWyles]

I’ve had good luck with the Ddhifi Tc28i lightning to usb c adaptor. It’s reliable and able to squeeze out as much current as is possible with the lightning port. They just released the Tc28i pro. It’s almost double the price but has two USB ports (1 for data and one for power), and it’s still cheaper and less bulky than the apple otg powered adapter. A jump from $29 to $49 seems a bit high though