D802C has Bluetooth ....straying in everywhere (like most devices with BT). It is not as good as D802. Best tip is to avoid D802C. Bluetooth has no use in quality audio so it does not offer anything extra except convenience for smart phone users. We all know what we trade in for convenience 
Last edited:
Same hiss in all inputs also same with an external cd player.
My speakers is 90db.
Its go to automute when no connection.
My D802 also has a bit of noise but not really noticeable unless there is very very quiet passage. However I did some mod to lower the noise floor (now I have to get close to my 85db efficient speaker to hear it )
I believe the problem is the power supply for the digital section, both the 3.3v of the st326 and the digital input/processor which uses a lm2956 buck converter to step down to around 11v and then to 2 x lm317 for the 3.3v used in the st326 and other ic (ak4113, usb ic, and processor).
D802 made it worse by splitting the digital supply off very close to the st326 supply (in fact from the closest power cap), imagine all the noise from the st326 switching injecting into the digital section. From the underside of board I cut off the digital section power trace and directly solder a wire from power input to the cut off point with a 10R resistor in series and add few 10uf/50v smd decoupling. The result is a quieter amp and reduce digital glare in some less well recorded music.
I believe the problem is the power supply for the digital section, both the 3.3v of the st326 and the digital input/processor which uses a lm2956 buck converter to step down to around 11v and then to 2 x lm317 for the 3.3v used in the st326 and other ic (ak4113, usb ic, and processor).
D802 made it worse by splitting the digital supply off very close to the st326 supply (in fact from the closest power cap), imagine all the noise from the st326 switching injecting into the digital section. From the underside of board I cut off the digital section power trace and directly solder a wire from power input to the cut off point with a 10R resistor in series and add few 10uf/50v smd decoupling. The result is a quieter amp and reduce digital glare in some less well recorded music.
Thanks for the info Chuck.
I think I know now why I have never heard any hiss at all from my 802. My speakers are 86db and I play gapless so there are generally no silent passages for me to hear hiss, if there are any they are only during music play when I am in my normal listening position, from where hiss is too low to be audible.
If the amp is automuting with no signa as describedl that might explain why I haven't heard hiss when operating the equipment and closer to the speakers. Out of interest - how does one tell if the amp is
muting? (apart from the useless 'mute' light which is for me permanently on even if playing)
Anyway- still enjoying hiss free music here
I think I know now why I have never heard any hiss at all from my 802. My speakers are 86db and I play gapless so there are generally no silent passages for me to hear hiss, if there are any they are only during music play when I am in my normal listening position, from where hiss is too low to be audible.
If the amp is automuting with no signa as describedl that might explain why I haven't heard hiss when operating the equipment and closer to the speakers. Out of interest - how does one tell if the amp is
muting? (apart from the useless 'mute' light which is for me permanently on even if playing)
Anyway- still enjoying hiss free music here
As I read it, the "hiss" described by Launagis is not as serious as the problems of hiss/auto-muting/low-gain described by Solve.
OK, this isolates the problem to the amplifier. Either there's a really bad setting in the menu, otherwise I think your unit is faulty.
Mine mute when no connections and volume at zero.Thanks for the info Chuck.
I think I know now why I have never heard any hiss at all from my 802. My speakers are 86db and I play gapless so there are generally no silent passages for me to hear hiss, if there are any they are only during music play when I am in my normal listening position, from where hiss is too low to be audible.
If the amp is automuting with no signa as describedl that might explain why I haven't heard hiss when operating the equipment and closer to the speakers. Out of interest - how does one tell if the amp is
muting? (apart from the useless 'mute' light which is for me permanently on even if playing)
Anyway- still enjoying hiss free music here
Also my led is constant lightning.
Also mute between songs in the little gap with an click.
Not very nice.
Yes It maybe a faulty amp.
Read at Amazone one had similar problem.
Bad firmware?
Thanks gwingn, I forgot to reply. Since my initial question I have done some Googling on this subject.
I found some reports on the web that the D802 does not perform well with 4 ohm speakers - increased noise, distortion.
But from your answer I wonder if those problems were with a higher voltage power supply - 32V or so? And the fix would simply be to use a 24V supply instead?
In any case, my NS3-193 speaker drivers are available as an 8ohm version, so maybe I will play it safe and use those instead.
That's what I would do as the 802 should actually be best with 8 ohm, although that would require a 30+V supply to attain maximum output. The amp comes OOB with a 24V supply - which is ideal for 4 ohm speakers but still works with 8.
On last sanity check though. When you play conventional CD player straight into amp, do you still need 04 gain levels on the amp or is it 10->20+ depending on your volume preferences?
Thanks. This system is just for TV/blu-ray viewing (I'm building a more high end system for music). So 24V should be fine.
Similar with 802C. Silent at 0, and same level hiss from 1 to max i could go, at around 20 it stops being noticeable. Mute between songs and gentle pop is also audible.
And another check
You have got the EQ set to flat and not some other 'music enhancing' value haven't you? I'm suspicious of the 'tone' button on the remote as well but haven't figured out what it is actually doing yet.
And another check
Yes have it on flat,the others just sound bad.
My bad. The standard supply on my 802 is 32V|5A which is good for 8 ohm. 4 Ohms would only need 24V.
And another check
'tone' button is used to toggle the DSP in ON and OFF
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.