Random Noise On Powered Monitors

[manoy385]

Hi All,

I am randomly encountering some weird noise on my Genelec 8030Cs. My setup consists of an SMSL M300 MkII which feeds the 8030Cs through the XLR out and an SVS PB-1000 sub through the RCA outs. The noise is usually only on one speaker but it would sometimes move between left and right channels. I tried using different computers, usb and optical inputs on the M300, different XLR cables and adding ferrite chokes on the cables but the noise still remains. When I disconnect the XLR cable from the 8030Cs, there is no noise but I can hear a faint hiss if I stick my ears close to it which I think is normal. There are times where the noise would go away too but when it is there it is loud enough that I can hear it from more than a meter away when nothing is playing. Anyone know what could be causing this?

 

[AnalogSteph]

Do you see any correlation with where the noise appears and the location of your phone? It sounds like there might be RF interference from some sort of non-stationary source, and usually there's a very limited number of those around.

 

[manoy385]

Do you see any correlation with where the noise appears and the location of your phone? It sounds like there might be RF interference from some sort of non-stationary source, and usually there's a very limited number of those around.

Turned off my phone and disabled wifi on my router and there is still noise. I'm thinking there is something wrong with the M300 but I do not have another balanced DAC around to test.

 

[manoy385]

M300 MkII is going back to Amazon. Gustard X16 on order and will arrive in a week. Really hope it won't have the same issue as I don't want to spend any more money and just want a working setup.

 

[vlad335]

I dont know if returned the SMSL yet but I just got one and it is excellent. Might be a weird ground issue using both outputs. I have a similar setup, a pair of Adam A5X and a SB-1000. you could try to hook it up another way. Get XLR female out from the DAC to RCA to the sub then out from the RCA's of the SVS to the studio monitors. Dead quiet. I cannot even tell my system is on.

The SVS has a built in 80hz high pass and it sounds quite good. Surprisingly good actually. Your Genelecs will be high passed and will sound a lot better with the sub bass duties taken from them.

 

[vlad335]

Always wanted to try the Gustard but i hate shipping from China.

Been on a tear lately trying DAC's. The SMSL M300 is the latest and it's brand new today but I am really liking it.

So far i have the Hifi S2, Topping E30 and D50s, Sabaj D5, a couple sound cards and now the M300. Through my system I listed above they all sound very different. Its surprising how much so.

 

[Berwhale]

So far i have the Hifi S2, Topping E30 and D50s, Sabaj D5, a couple sound cards and now the M300. Through my system I listed above they all sound very different. Its surprising how much so.

Most of the DACs you mention have been tested on ASR and have measurements that show them to be 'audibly transparent'. Any differences you 'hear' are almost certainly down to the way you compared them and your brains inherrent cognitive biases.

Have you read this thread? Audibility thresholds of amp and DAC measurements | Audio Science Review (ASR) Forum

 

[Berwhale]

@manoy385 Does the noise go away when you disconnect the sub?

I recently swapped a pair of Tannoy Reveal 402 monitors (which had no safety ground i.e. figure of 8, 2 pin power connector) for a pair of iLoud MTM (which have a saftey ground i.e 3 pin power connector). I immediately created a ground loop between my PC and the monitors. The solution was to insert a cheap USB isolator between the PC and DAC...

Nobsound USB to USB Isolator Module Audio Noise: Amazon.co.uk: Electronics

 

[manoy385]

I dont know if returned the SMSL yet but I just got one and it is excellent. Might be a weird ground issue using both outputs. I have a similar setup, a pair of Adam A5X and a SB-1000. you could try to hook it up another way. Get XLR female out from the DAC to RCA to the sub then out from the RCA's of the SVS to the studio monitors. Dead quiet. I cannot even tell my system is on.

The SVS has a built in 80hz high pass and it sounds quite good. Surprisingly good actually. Your Genelecs will be high passed and will sound a lot better with the sub bass duties taken from them.

I already returned the M300. Isn't XLR balanced supposed to eliminate ground loop noise? I will try it without hooking up the sub if I still get noise with the Gustard. I actually think it might be the cables too since I'm using cheap ones that might not have sufficient shielding.

 

[vlad335]

Most of the DACs you mention have been tested on ASR and have measurements that show them to be 'audibly transparent'. Any differences you 'hear' are almost certainly down to the way you compared them and your brains inherrent cognitive biases.

Have you read this thread? Audibility thresholds of amp and DAC measurements | Audio Science Review (ASR) Forum

Ok, this has been done on the internet and this forum a million times. There are differences and no one will ever convince me that there is not. To me, mostly in the bass. ( they all sound pretty much the same in the high frequencies to me.) Perhaps its how the different DAC's react with my speakers and sub IDK but i am not going to get into this because it's endless.

 

[manoy385]

@manoy385 Does the noise go away when you disconnect the sub?

I recently swapped a pair of Tannoy Reveal 402 monitors (which had no safety ground i.e. figure of 8, 2 pin power connector) for a pair of iLoud MTM (which have a saftey ground i.e 3 pin power connector). I immediately created a ground loop between my PC and the monitors. The solution was to insert a cheap USB isolator between the PC and DAC...

Nobsound USB to USB Isolator Module Audio Noise: Amazon.co.uk: Electronics

It can't be the USB port since I tried it with multiple PCs and also with optical out from my desktop and they all still get the noise.

 

[vlad335]

I already returned the M300. Isn't XLR balanced supposed to eliminate ground loop noise? I will try it without hooking up the sub if I still get noise with the Gustard. I actually think it might be the cables too since I'm using cheap ones that might not have sufficient shielding.

Yeah, XLR should take care of that. The suggestion for the USB isolator above is excellent

 

[BDWoody]

Ok, this has been done on the internet and this forum a million times. There are differences and no one will ever convince me that there is not. ... i am not going to get into this because it's endless.

Then don't start, if you don't expect someone to remind you that this is a science forum, and making extraordinary claims will generally get called out as such.

 

[Berwhale]

I already returned the M300. Isn't XLR balanced supposed to eliminate ground loop noise? I will try it without hooking up the sub if I still get noise with the Gustard. I actually think it might be the cables too since I'm using cheap ones that might not have sufficient shielding.

I don't know how the RCA and XLR connections are wired internally, but connecting the RCA cables to the DAC creates an opportunity for a ground loop. So it would certainly be worth temporarily disconnecting the RCA to test if it made a difference.

 

[manoy385]

I don't know how the RCA and XLR connections are wired internally, but connecting the RCA cables to the DAC creates an opportunity for a ground loop. So it would certainly be worth temporarily disconnecting the RCA to test if it made a difference.

Before I had the Genelecs, I used the M300 RCA out to an Emotiva A100 which powered a pair of KEF Q150s and never got any noise from them.

 

[Berwhale]

Before I had the Genelecs, I used the M300 RCA out to an Emotiva A100 which powered a pair of KEF Q150s and never got any noise from them.

The Emotiva A-100 has a 2 pin figure of 8 power connector, so no safety ground connection or path for a ground loop to form...

The speakers are irrelevant because they have no connection to ground.

 

[vlad335]

Then don't start, if you don't expect someone to remind you that this is a science forum, and making extraordinary claims will generally get called out as such.

Extraordinary?

Ok. They all sound exactly the same.

 

[BDWoody]

Extraordinary?

Ok. They all sound exactly the same.

You can go straight to disingenuous if you like, but if you actually controlled your subjective listening process, that's very likely the conclusion you would come to.

If you don't want to bother with the controlled listening part (level matched, filter matched, blind test), boldly stating otherwise is the extraordinary claim, at least around here.

 

[manoy385]

The Emotiva A-100 has a 2 pin figure of 8 power connector, so no safety ground connection or path for a ground loop to form...

The PB-1000 also uses the same 2 pin figure 8 power connector so no ground loop there. The only component in my setup now with 3 prongs on the power connectors now are the Genelecs. The Gustard X16 has 3 prongs too so will that affect it too?. The X16 should arrive next week and I will update this thread if I get noise from it too.

 

[manoy385]

Welp my X16 just got delayed 2 weeks because of Chinese new year. Looks like I won't be using my Genelecs for almost a month.