[Erick Muller]

From my personal experience, the current setting is the only thing that has an effect on the heating (apart from room temperature). My unit goes from 28 °C to 62 °C (50 ma) or 69 °C (100 ma) within one hour of turning it on. Regardless if there any cables connected or not - this thing doesn't know if music is being played.

As for sound quality I need more time to be sure of my evaluation (I would say for now that my biggest gain was regarding dynamics - coming from a Chord Mojo 2 as DAC & Amp).

You need to put some airflow under that machine, have you try elevating a little bit from the surfarce you have your amp on like with some speaker feet or something like that?

 

[MiguelP]

Not exactly my experience Simon.

I've been running HD650s on my S17 regularly at high gain, full tilt on 100ma mode and it never gets above 65, even with my minisplit heating up the room, tho I don't really have high impedance planar cans to test this theory(only my LCD2Cs and those are like 70ohm planars, middle of the road when it comes to planar efficiency for what I have seen). Like I mentioned before, the two cases where I have noticed that temps spike up really fast is with the 3m long xlr cable that comes with the focal clear's connected to any of my focals, it gets the amp to 69 degrees relatively fast and the other even more fascinating case is with the koss khp40 with a balanced 4.4mm cable, it gets to 69 also but much faster. There's something weird going on with my unit or there's something about this cables that are casing some weird edge case issue with the amp or there's a weird issue with the amp itself.

I haven't read anyone else having this problem but I also haven't seen anyone else having tested this amp in the same way as I did, specially with the long xlr cable from focal because I think most people either throw away that cable or leave it in the box because is goddamn awful lol!!!. Zeos did try his S17 with the same set up of koss kph 40s running the same cable and it seem the temps went up fast for him also(btw, Zeos is right, the khp40 scale with this mofo and they sound amazing also, specially on 100ma mode, and also I was running them at low gain and it seems zeos was also running them at low gain)

Mine doesn't care about which (or if any) cables are connected. It heats just by being on. It's with raised feet (25mm), in top of a metal perfurated stand. Also tried two fans underneath but it was the same. 1 hour turned on in 50ma= 62 °C, 1 hour turned in in 100ma = 69 °C. The unit gets unconfortably hot to touch it (even the volume knob feels hot). I'm guessing most users will only notice it in the summer - where I am is winter but with 30° C day temperature

 

[MiguelP]

You need to put some airflow under that machine, have you try elevating a little bit from the surfarce you have your amp on like with some speaker feet or something like that?

I've tried everything.

 

[MiguelP]

 

[jinu117]

Loving the idea of S17/S9C chassis DAC only. I can see how it can be stacked nicely (with bit taller leg...) and look beautiful. Considering I myself ended up trying it based on merit of S9C I've experienced, I can only imagine what this will bring if DAC is worthy successor to complement prowess of S17 (I do expect DAC to be better than S9c obviously).

As for S17Pro, I have very mixed feeling at this point. Quite honestly though by addressing few things, I can see great things for this AMP (especially if there will be fellow DAC that goes with this... in future).
1. Handling of temperature - I am sure there need to be hardware change to really accommodate this if it is actually thermal issue. (I have suspicion that it might be calibration of temp sensor inside). For unit to unit variation being so high doesn't make sense to me unless the thermal solution was physically installed inconsistently. Regardless, it would be probably possible to use the big hunk of aluminum chassis itself as heatsink (I would imagine retooling needed for interfacing this to what I would assume heatsink or such inside the unit... just curious... does anyone have internal pic of the unit?)
2. Handling of defective, warranty, etc inside US. I noticed you have listed distributor in US which doesn't seem to be operating their website as listed nor can find it in google to see if such business exists. http://www.extremaudios.com.
While Amazon would be awesome for first month, what about after that? I myself had to return product bought from HIFIGO, both the vendor and I had to go through extra amount of effort and trouble to trying to return the defective unit I received and at the end of the day, I got my money back, HIFIGO probably lost whole bunch, and unit is stuck in customs in China and probably will be destroyed. It really left bad taste in my mouth.

I kind of wish S17 sounded bad/mediocre so I won't even have to bother with it at this point.. but it is such a alluring product with the look and performance. Looking forward to maybe minor updates and improvement to this great product into perfect solution for many.

 

[Erick Muller]

Mine doesn't care about which (or if any) cables are connected. It heats just by being on. It's with raised feet (25mm), in top of a metal perfurated stand. Also tried two fans underneath but it was the same. 1 hour turned on in 50ma= 62 °C, 1 hour turned in in 100ma = 69 °C. The unit gets unconfortably hot to touch it (even the volume knob feels hot). I'm guessing most users will only notice it in the summer - where I am is winter but with 30° C day temperature

Mine doesn't do that Miguel.

I do have it supported on 4 of these

I leave the amp on all the time, but when I'm not using it I leave at low gain at 50ma mode and it stays in the middle 40s, tho I do have a window right in front of my desk and a leave it a little bit open, but even with the window closed, it never gets above 49 degrees when not in use and with the settings I mentioned before.

 

[Erick Muller]

Yep, you have even better airflow than my setup, the amp shouldn't be exhibiting that behavior imho, you need to get in contact with aune.

 

[Erick Muller]

Loving the idea of S17/S9C chassis DAC only. I can see how it can be stacked nicely (with bit taller leg...) and look beautiful. Considering I myself ended up trying it based on merit of S9C I've experienced, I can only imagine what this will bring if DAC is worthy successor to complement prowess of S17 (I do expect DAC to be better than S9c obviously).

As for S17Pro, I have very mixed feeling at this point. Quite honestly though by addressing few things, I can see great things for this AMP (especially if there will be fellow DAC that goes with this... in future).
1. Handling of temperature - I am sure there need to be hardware change to really accommodate this if it is actually thermal issue. (I have suspicion that it might be calibration of temp sensor inside). For unit to unit variation being so high doesn't make sense to me unless the thermal solution was physically installed inconsistently. Regardless, it would be probably possible to use the big hunk of aluminum chassis itself as heatsink (I would imagine retooling needed for interfacing this to what I would assume heatsink or such inside the unit... just curious... does anyone have internal pic of the unit?)
2. Handling of defective, warranty, etc inside US. I noticed you have listed distributor in US which doesn't seem to be operating their website as listed nor can find it in google to see if such business exists. http://www.extremaudios.com.
While Amazon would be awesome for first month, what about after that? I myself had to return product bought from HIFIGO, both the vendor and I had to go through extra amount of effort and trouble to trying to return the defective unit I received and at the end of the day, I got my money back, HIFIGO probably lost whole bunch, and unit is stuck in customs in China and probably will be destroyed. It really left bad taste in my mouth.

I kind of wish S17 sounded bad/mediocre so I won't even have to bother with it at this point.. but it is such a alluring product with the look and performance. Looking forward to maybe minor updates and improvement to this great product into perfect solution for many.

That's really unfortunate Jinu, really sad to hear that.

I had a couple of issues with my particular amp but for what I can gather, they're probably edge cases like a mentioned before, but other than that, temp stability hasn't been much of an issue for me with the rest of my headphone collection and in the case of my focals, I just needed to change the cables, that just leaves the super weird case of my koss kph 40s, but the amp does seem to be a little bit temperamental tbh.

 

[Erick Muller]

Btw Miguel, where did you get that metal rack? I would like to get something like that for my setup

 

[Erick Muller]

@jinu117 @MiguelP I ordered my S17 from HIFIGO on the 7th of November, when and from where did you get your amp?

Also maybe @AuneAudio could clarify if there was a revision to the S17 in newer batches and that's why we're experiencing different behaviors from this amp?

 

[TheFritz]

I had mine in a similar, very well ventilated setup at the beginning, always in 100mA mode and it never reached the 69 deg C limit. I never noticed any dependency of the temperature on the cables or the headphone impedance.
But it the meantime I moved the aune S17pro to a much more confined space to have it directly at my workplace/favorite listening location. It is still on a metal shelf an I raised it by 2cm but there it broke the temperature barrier in about an hour (room temp. is 21 deg C). Inspired by one post here, I placed 4 massive aluminium discs underneath, touching the enclosure and the metal shelf and the shelf got warm aswell, transporting some heat away but that only delayed the 69deg switch-over by approx. 30 minutes. I finally resorted to 2 USB-fans (I have a burson soloist 3xGT with built-in fan so I am not completely against active cooling). Placing them on top of the device kept it below 69 deg C but just barely at 68deg. Raising it more and placing the fans behind was an improvement, keeping the temperature at 65/66. The best solution is to place the S17 directly on the fans (with spacers obviously); this way it reaches only 63deg. I plotted the temperature curves but did not watch it every minute and the time axis (x) is not time after switching it on but a bit arbitrary.
Green is with aluminium plates as heat bridge, blue is fans above the S17, yellow fans behind it with it 3cm raised and dark green with the S17 placed on the fans... all in 100mA mode.

EDIT: The fans below it:

 

[jinu117]

@jinu117 @MiguelP I ordered my S17 from HIFIGO on the 7th of November, when and from where did you get your amp?

Also maybe @AuneAudio could clarify if there was a revision to the S17 in newer batches and that's why we're experiencing different behaviors from this amp?

Ordered on Nov 25th and received it on 12/12. Got it from HIFIGO. Mine had no volume control issue, only 4.4mm Jack defect and quicker over heating than the subsequent unit I got from Amazon. Basically these 2 unit have totally different heat characteristics despite being positioned at same location, used by same equipment and same room temp. (in excess of about 8c or so).

PS) Aluminum plate idea only increases thermal mass to slow down initial heating to be honest... you are not increasing surface area by much at all.. Also, I am wondering if heat is conducted directly to casing in first place. I am assuming it is radiating and convective heat, not conductive to chasis.

 

[Erick Muller]

I had mine in a similar, very well ventilated setup at the beginning, always in 100mA mode and it never reached the 69 deg C limit. I never noticed any dependency of the temperature on the cables or the headphone impedance.
But it the meantime I moved the aune S17pro to a much more confined space to have it directly at my workplace/favorite listening location. It is still on a metal shelf an I raised it by 2cm but there it broke the temperature barrier in about an hour (room temp. is 21 deg C). Inspired by one post here, I placed 4 massive aluminium discs underneath, touching the enclosure and the metal shelf and the shelf got warm aswell, transporting some heat away but that only delayed the 69deg switch-over by approx. 30 minutes. I finally resorted to 2 USB-fans (I have a burson soloist 3xGT with built-in fan so I am not completely against active cooling). Placing them on top of the device kept it below 69 deg C but just barely at 68deg. Raising it more and placing the fans behind was an improvement, keeping the temperature at 65/66. The best solution is to place the S17 directly on the fans (with spacers obviously); this way it reaches only 63deg. I plotted the temperature curves but did not watch it every minute and the time axis (x) is not time after switching it on but a bit arbitrary.
Green is with aluminium plates as heat bridge, blue is fans above the S17, yellow behind with it 3cm raised and green with the S17 placed on the fans... all in 100mA mode.


EDIT: The fans below it:

In the last photo with the fans bellow, is there still a heat bridge using the large aluminum plates?

This seems like the best solution to keep temp stability on the amp, but it's a bit cumbersome tbh and I don't see a lot of people going to such extends to keep it cool.

 

[Erick Muller]

Ordered on Nov 25th and received it on 12/12. Got it from HIFIGO. Mine had no volume control issue, only 4.4mm Jack defect and quicker over heating than the subsequent unit I got from Amazon. Basically these 2 unit have totally different heat characteristics despite being positioned at same location, used by same equipment and same room temp. (in excess of about 8c or so).

PS) Aluminum plate idea only increases thermal mass to slow down initial heating to be honest... you are not increasing surface area by much at all.. Also, I am wondering if heat is conducted directly to casing in first place. I am assuming it is radiating and convective heat, not conductive to chasis.

I can understand how this whole experience has left a sour taste in your mouth regarding this amp, it's unfortunate really because the sound that this amp produces is just amazing and it's a shame that it has been plagued by so many issues for so many users.

 

[TheFritz]

In the last photo with the fans bellow, is there still a heat bridge using the large aluminum plates?

This seems like the best solution to keep temp stability on the amp, but it's a bit cumbersome tbh and I don't see a lot of people going to such extends to keep it cool.

No. I removed the aluminium discs. The spacers are shock absorbers to prevent this construction from slipping around and to allow air to flow. I should also mention that the two USB-fans are much quieter than the expensive one in the burson 3xGT and only at the lowest of their 3 speed setting. I barely notice them without headphones and not at all with headphone on.