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O-Noorus D3 PRO - A new TPA3255 PFFB amplifier with DAC

It won't have parental controls, Roy.
What you can do is transfer only the safe functions to a universal remote control and keep the original remote control away from your child.
i'm really curious about that included heatsink
 
It won't have parental controls, Roy.
What you can do is transfer only the safe functions to a universal remote control and keep the original remote control away from your child.
The ok button cycles through to there but that's also needed to reach input selection...
 
Also these two modes are mystery and I am afraid to test now
 

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@Roy_D Could you control left/right speaker level chanel ?
 
Thermal pad on heatsink on amp at 20 volume temp heatsink 35 take it off temp case 40 so actual benefit I'd say not much unless a constant breeze was at play then the added surface area might bleed off more heat from the case.

On the bottom of the case there are 3 rows of 2 long vent slits but they are mostly closed as it appears a heatsink attached to the class D chips on the underside of the board is attached to a metal plate which is screwed tight into the bottom of the case which then closes off all but one slither of one of the 6 slits on the bottom.
Basically the whole case is heatsink.
I think a heatsink on the bottom night have been more practical but less effective. Heatsinks without steady drafts or fan are just buffers.
 

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Ok so one very unpleasant suprise; no manual is included with the amplifier @Alexander Lin and in going through the remote options I came across one that suddenly put the amp into full volume mode. I hope it did not damage my ears or speakers. I was exposed to the loudest sound ever for a short time. Highly unpleasant and worrisome.
If my son triggers that by accident for example. But for now I am really wondering whether my hearing was damaged by the incident. I was very close to one speaker.

The manual has not been produced yet, but SF Express (Shunfeng Express) logistics is much faster than we expected. We wanted to send you the electronic document manual before you received the goods, and it will be sent by email today.


The sound is good. I would response is flat as can be - as far as I can tell by ear.
Pleasant bass mids highs at 40dB. Some of the highs on this Kef Q100 are higher than usual of course but nothing the amp is doing is making that any worse is what I'm hearing.
Remote responsive. Lots of inputs. Nice clear display at a distance. No bitrate displayed but cant have everything.
Except for that incident with the it going full volume - and I hope there is a way to childlock that away @Alexander Lin !? - all in all pretty darn neat.
And warm. I wonder if placing that heatsink is a must for longevity. Or of perhaps we can apply a thermal pad to internal components and have in interface with the case, and make some more perforations?
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This is the internal heat sink, and it does not block the slot under the shell.
 
that might be it - I will try gently tomorrow lol..
The precision of the electronic volume is 0.5db. When the left and right channel balance is set to 0, the gain is 29db, and the channel balance changes by 5db from (-5) to (+5). For example, if the volume is set to 50, the left channel balance is set to (-5), and the right channel is set to (+5), the actual left channel is 45 and the right channel is 55. However, the volume display is still 50.
 
The manual has not been produced yet, but SF Express (Shunfeng Express) logistics is much faster than we expected. We wanted to send you the electronic document manual before you received the goods, and it will be sent by email today.



View attachment 457104View attachment 457105
This is the internal heat sink, and it does not block the slot under the shell.

Thank you I will keep an eye on my mailbox.
On closer inspection moving the amp back and forth for being able to gauge depth better and with a bright light I do see there is some clearance between the internal heatsink and the vent slits but was easy to miss. Was I wrong as well to assume the two screws in the vent slit/ heatsink area are to secure part of the heatsink to the shell of the amplifier?
 
One behaviour of the amplifier I hope can be remedied through an update is that when powering back up after having been disconnected from the mains is that the volume is set to 40 which if it were to pick up any input and start amplifiying at that level would not be pleasant. I have a mains power extension with on/off switch as many people do and use that to switch off all media equipment overnight. It seems not to recall I left it at 10 the previous evening and this default volume level given the amplifier efficiency is very high as a default.

But so far sonically very happily enjoying music - the amplifier is performing well
 
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One behaviour of the amplifier I hope can be remedied through an update is that when powering back up after having been disconnected from the mains is that the volume is set to 40 which if it were to pick up any input and start amplifiying at that level would not be pleasant. I have a mains power extension with on/off switch as many people do and use that to switch off all media equipment overnight. It seems not to recall I left it at 10 the previous evening and this default volume level given the amplifier efficiency is very high as a default.
When you shut down the machine with the remote control, all parameters will be remembered, just once.
Instead of directly cutting off the power.
 
When you shut down the machine with the remote control, all parameters will be remembered, just once.
Instead of directly cutting off the power.
I thought I had switched off using the main control button on the amplifier last night. I just repeated this with volume set to 6 at the moment, switched off the mains power and waited a minute or so, then switched mains power back on and powered on the amplifier longpressing the volume/on off button as before and yes volume 6!

**edit and again with a few hour hiatus tye D3 Pro started back up with volume set where I had left it

Nevertheless I think it may save some buyers some unpleasant surprises Alexander if the amplifier did not have a factory volume setting of 40 ^_^
 
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Yes I found the film.^^ Not un unattractive device this is. The display is clear and practical in living room situation being legible from a distance. Being able to set colour and brightness are welcome features.
The remote is responsive has a nice wide angle of range and all functions are easy and simple. Adjustable bass and treble for low listening levels is useful also. I note a little thin thump coming from speaker when going from +1 bass to 0 bass.
There are audible thin thumps switching the amp on and off and they happen with a few seconds of delay.
Input switching there are audible relais clicks in the back when selecting certain inputs and when switching the amp off.

Temperature seems independant of load. Playing for long period on volume 5 or 25 yields no meaningful difference in temperature which is around 42.5 maximum (highest near and at the display) (ambient temp is 24)

I've had set the amp on top of the included heatsink with the fins up and this has a bit if a positive effect on temperatures, basically by raising the amp off the surface. A C lower here and there. But temperature remains higher than I wish so I've set the d3 pro on top of a very quiet Be Quiet pwn fan which is inaudible at the level I set it to run at and the amp exterior now measures 35°C with ambient temperature of the room at 24.4.

Or is the amp case at 42C° fine and nothing to worry about @Alexander Lin ?

.
 
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I received the manual from O-Noorus in my emal - it is too large to share on the forum sadly though but I can share the google drive link I got from them.
@Alexander Lin the format of the manual is problematic: it is one large page and on desktop webbrowser for example it refuses to zoom in to page level.
Even print option is problematic - it is having great difficulty handling this file and this is a very new up to date pc.. It can only print all pages as one page which makes it totally illegible and unusable.

Please have them reformat the PDF so it can be read and viewed as page by page booklet?
Also I am interested to see the frequency response graph to see how effective the pffb measures up - they are not included in the set in the pdf?
 
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