New Practical Devices XM6 Amp/DAC (The Complete Review)

[Armaegis]

Thanks for the impressions. I've always been curious about this, but have not been into portables as much lately. 

 

[Mark-sf]

I have just tried using the XM6 with my Beyerdynamic DT1350's I use in my office. Unfortunately the XM6 has a "Low Gain" setting of +10db which does not play well with the 1350's 109db efficiency. As a result I can only use the initial 10-15% of the volume control's rotation. Fortunately the pot has no tracking problems in that range. Now the 75ohm load switch does significantly knock the gain down but since the 1350's impedance is 80 ohms it rolls off the high end. I normally use my iBasso D-Zero which only has a low gain setting of +3db and works extremely well as it uses the same Wolfson DAC family in the 8740. 
 
Even with this volume control issue, the combo really establishes the bass end and demonstrates how truly low the 1350's can go. It's quite visceral. 

 

[fuzzy1969]

I got the xm6 today, initial impressions very positive, out of curiousity I hooked it up to my samsung s3 phone via the usb OTG cable and it works well, I suspect the DAC stage is drawing power from the phone but its below or equal to the phone limit (I think about a 100ma).

 

[Mark-sf]

I have been using my XM6 for about 10 days with a variety of headphones/IEMs. I can say at this point that it works great with on-ear and over the ear cans of moderate to high impedance. I have had hours of enjoyment with both my DT1350's and HD700's. Due to its high low-gain setting of 10db, it is not a good match for sensitive IEM's such as my TripleFi 10's. You end up with very little volume control range (7-8 o'clock) though the amp is dead silent. I would much rather of seen the gain to be more in the range of 3-5db for Low and 10-12 for high. 
 
One thing I noticed on mine, is that when I use it as a DAC/AMP on either my Macbook or Thinkpad, it gets quite warm even though it is not charging and I do notice an electronics high temp smell from the back. Is this unique to my unit or are others here noticing this?

 

[Armaegis]

I think you should definitely email them about that smell... 

 

[Mark-sf]

Did some serious troubleshooting tonight and discovered the issue was the PD supplied USB cable! Not sure why but substituting it eliminated both the heat and the smell.  I will send a email to James and see what he has to say.

 

[Armaegis]

That is very peculiar... hope it didn't fry anything inside 

 

[fuzzy1969]

Mine gets warm Im driving 300ohm hd650's I havn't noticed a smell though, I got it off ebay with a reported 400 hours use. Ill try to spend more time with it.

 

[dryvadeum]

Quote:

I got the xm6 today, initial impressions very positive, out of curiousity I hooked it up to my samsung s3 phone via the usb OTG cable and it works well, I suspect the DAC stage is drawing power from the phone but its below or equal to the phone limit (I think about a 100ma).

Would you say your PCStep is better overall in sound quality?

 

[fuzzy1969]

I havn't spent much time with the xm6 to be honest, its certainly good in its own right from the brief time Ive spent with it, I seem to have acquired to many DAC's in a short space of time. The PCSteps presentation is quite a bit different to the apex and xm6 in regards to authority the PCStep has in the bass department. Ill give the xm6 a listen over the weekend.

 

[dryvadeum]

I havn't spent much time with the xm6 to be honest, its certainly good in its own right from the brief time Ive spent with it, I seem to have acquired to many DAC's in a short space of time. The PCSteps presentation is quite a bit different to the apex and xm6 in regards to authority the PCStep has in the bass department. Ill give the xm6 a listen over the weekend.

Thanks for that info. So the XM6 is compatible with the S3 through USB OTG?

 

[fuzzy1969]

Yes works a treat, the one I picked up has the wolfson 8741 installed and came with a AD8397 op-amp/buffer to swap in, I should really spend some time with it.

 

[dryvadeum]

Quote:

Yes works a treat, the one I picked up has the wolfson 8741 installed and came with a AD8397 op-amp/buffer to swap in, I should really spend some time with it.

Yeah, I like the features it has. Does the bass boost affect the definition of the bass or make it muddy?

 

[fuzzy1969]

Seems to give the bass more emphasis, makes it deeper with the hd650's doesn't seem muddy just louder.

 

[Jesterphile]

Just (Hopefully) picked one of these up second hand - pretty excited to hear it. Has the WM8471 and AD8397 upgrades too.
 
Hoping it works nicely with my Nexus 7 and laptop