Fiio DAC cabled by mistake to phono in

[hybridauth_Facebook_1080975575266793]

Hello,

i recently moved my Denon PMA-520AE from my office and when i started cabling everything back

i plugged by mistake the line out connector from the Fiio DAC to phono in on the Denon amp.

The speakers made a very loud noise because everything was powered on and music was playing through the DAC.

The problem is that now i have some white noise on both channels and i don't know if this was caused by my cabling mismatch or if it is an expected behavior for this amp.

Please advise.

Thanks !

 

[MeanandGreen]

Always switch off the power on everything in the chain when making and breaking connections. Have you now plugged the DAC into a standard line input or is it still plugged into the phono stage?

 

[hybridauth_Facebook_1080975575266793]

Hi,

now i have everything plugged correctly.

the mismatch of the cables happened for about 2 minutes until i figured out that something is wrong ( i had no sound ).

Is it possible that i damaged the DAC/Amp during this process ?

Thanks for the reply !

 

[davedotco]

It is possible that you mistake has damaged your amplifier but unlikely. You need to go through a logical fault finding process and report your findings.

Start by disconnecting everything from your amplifier bar your speakers, double check the speaker connections and do turn the amp off first. Then turn the amp on and compare the noise level on each input as you turn up the volume, what can you hear with the amp at, say, half way and at full volume?

Then connect your source(s), one at a time and to the correct input, and do the same, with no music playing. Then with music playing at normal volumes, not at full volume, in fact no mare than half way. Report what you hear, that should give anyone on here a decent idea what is going on.

 

[hybridauth_Facebook_1080975575266793]

Ok, so i followed your advice and i disconnected everything, one step at i time, EXCEPT the speakers from the amp.

In all my tests i found the following:

1. Having just the amp + speakers without any line in inputs (DAC in my case) gives the same amount of noise on my tweeters (it's not a big amount but it's there).

2. Rotating the volume knob with the above setup gave some strange results. When the volume is all the way down, the noise is hearable. When the knob is at 12 o'clock, the noise dissappears. When the knob is at full volume, the noise is back again.

The impact on the sound quality is close to none, but i am still worried

Thanks alot for your reply !

 

[hybridauth_Facebook_1080975575266793]

Also, i forgot to mention, that i checked my cabling from the amp to the speakers and everything is correclty placed.

Thanks !

 

[Covenanter]

It doesn't sound like you have done any permanent damage but the input sensitivity on the phono input is about 50 times more than on the line input so it wasn't a wise thing to do! Please always switch everything off before changing any wires and a good rule is to turn the volume down to zero when reconnecting any wiring and then gradually turn it up afterwards.

I can't immediately explain your symptoms though!

Chris

 

[davedotco]

Ok, so i followed your advice and i disconnected everything, one step at i time, EXCEPT the speakers from the amp.

In all my tests i found the following:

1. Having just the amp + speakers without any line in inputs (DAC in my case) gives the same amount of noise on my tweeters (it's not a big amount but it's there).

2. Rotating the volume knob with the above setup gave some strange results. When the volume is all the way down, the noise is hearable. When the knob is at 12 o'clock, the noise dissappears. When the knob is at full volume, the noise is back again.

The impact on the sound quality is close to none, but i am still worried

Thanks alot for your reply !

What happens to the noise with the dac connected but no music playing?

I am slightly concerned with the variation in the noise, but it may be quite normal for this model...*unknw*

 

[hybridauth_Facebook_1080975575266793]

When the DAC is connected I get the same behavior as described in point 2 from my previous post.

Thanks!

 

[davedotco]

If the noise is inaudible at your normal listening levels, from low to high volume, then I would forget it and carry on as normal.

When amps fail or are broken, it is usually pretty obvious, take the lesson about switching things off and move on.

 

[hybridauth_Facebook_1080975575266793]

First of all, thank you all for your answers and support.

Meanwhile i observed another "strange" thing with my amp: there is noise from phono stage also and it ascends with the volume. The higher the volume, the higher the noise. This doesn't happen with the other inputs. Worth to mention that the phono stage didn't have anything plugged in at the time of my tests.

I think i will request RMA for this one very soon

Thanks again !

 

[MajorFubar]

there is noise from phono stage also and it ascends with the volume. The higher the volume, the higher the noise. This doesn't happen with the other inputs. Worth to mention that the phono stage didn't have anything plugged in at the time of my tests.

That's normal, you're worrying over nothing.