Possible coil whine in my nMP

[michaeljk]

I hear no whine on my nMP (standard 6-core config). This weekend, after reading through this thread, I turned everything else in my office off--the external HDDs, monitors, external speakers, all other electronics (midi and recording gear). I sat in the office with the door closed (door has pro-level soundproofing added), sat and waited. I heard the faint whir of the fan from the nMP. Nothing else. I put my ear to the top of the nMP, waited for a good 30-60 seconds. Nothing but a fan whir.

I'm not saying others don't have real issues with their nMP. I will say I think I have very good hearing, including at low levels. Back when I had the PowerMac G5, I had not one, but two hum eliminators in my audio signal path and used an external power block between the PowerPC and the rest of the home electronics to separate additional possible signal noise. And I still never eliminated its whining, chirping, strange signal noise issues. So, I was a bit paranoid when I read this thread, after finally venturing back to the land of the Pro-Mac market ten years later (I actually sold the PowerMac in part because I had wanted to use it as my sound studio Mac and found it useless due to its chirping and humming).

I am glad to report that, either my hearing has deteriorated considerably in the past ten years (not that likely, although some to be sure), or this is not a universal problem, because my nMP exhibits none of the whining issues reported by others.

 

[Riwam]

You are a lucky owner of a good nMP!

I hear no whine on my nMP (standard 6-core config). This weekend, after reading through this thread, I turned everything else in my office off--the external HDDs, monitors, external speakers, all other electronics (midi and recording gear). I sat in the office with the door closed (door has pro-level soundproofing added), sat and waited. I heard the faint whir of the fan from the nMP. Nothing else. I put my ear to the top of the nMP, waited for a good 30-60 seconds. Nothing but a fan whir.

I'm not saying others don't have real issues with their nMP. I will say I think I have very good hearing, including at low levels. Back when I had the PowerMac G5, I had not one, but two hum eliminators in my audio signal path and used an external power block between the PowerPC and the rest of the home electronics to separate additional possible signal noise. And I still never eliminated its whining, chirping, strange signal noise issues. So, I was a bit paranoid when I read this thread, after finally venturing back to the land of the Pro-Mac market ten years later (I actually sold the PowerMac in part because I had wanted to use it as my sound studio Mac and found it useless due to its chirping and humming).

I am glad to report that, either my hearing has deteriorated considerably in the past ten years (not that likely, although some to be sure), or this is not a universal problem, because my nMP exhibits none of the whining issues reported by others.

.............................................
I do not believe your hearing is deteriorated in any way.
You simply received a computer keeping the 12dB noise threshold promised by Apple, which for any practical use is equal to silence.
Congratulations!

 

[macourteau]

FWIW, I get a "whine" sound in my nMP (8c, D700, 64GB RAM upgrade from OWC) as well, but only when it's idling (doing nothing). As soon as it's doing something, the sound stops. I can hear it but not everyone does (I have good hearing at high frequencies). It's being used in a studio, so it quickly becomes annoying.

I made a quick recording of the sound a couple of inches from the top of the nMP, both when idling (first half of my recording) and doing something (second half of my recording). I had to amplify the sound a lot (and also filtered out LF noise), but looking at the spectrum view in Audacity (see attached screenshot), there are very clear noises around 8kHz, 12kHz-13.5kHz and 16kHz-17kHz, which are significantly quieter when not idling...

 

[saschke]

Interesting, thanks. Looks like "your" whine has to do with the CPU power consumption, possibly with the CPU idle states or general power draw of the PSU.

 

[Riwam]

Very interesting! Would be great to measure the dB of it!

FWIW, I get a "whine" sound in my nMP (8c, D700, 64GB RAM upgrade from OWC) as well, but only when it's idling (doing nothing). As soon as it's doing something, the sound stops. I can hear it but not everyone does (I have good hearing at high frequencies). It's being used in a studio, so it quickly becomes annoying.

I made a quick recording of the sound a couple of inches from the top of the nMP, both when idling (first half of my recording) and doing something (second half of my recording). I had to amplify the sound a lot (and also filtered out LF noise), but looking at the spectrum view in Audacity (see attached screenshot), there are very clear noises around 8kHz, 12kHz-13.5kHz and 16kHz-17kHz, which are significantly quieter when not idling...

..........................
Do I see right and there is also a noise around 4 KHz?
It would be great if you find a way to measure the intensity of the sound!
Apple pretends the threshold is 12 dB but if you hear the sound, it should be much, much higher than 12dB.
Would be great if you try to measure the dB value of it, even with one of those free Apps available for the iPad but of course much much better with a better noise recording device if possible!

 

[macourteau]

Interesting, thanks. Looks like "your" whine has to do with the CPU power consumption, possibly with the CPU idle states or general power draw of the PSU.

That's possible. Are there settings for this anywhere?

..........................
Do I see right and there is also a noise around 4 KHz?

That could be the room or some of the spread-spectrum noise from the fan (the phone was directly over the nMP so it also picked up "wind" noise from the fan blowing air out). It could also be the phone's microphone/ADC amplifying those frequencies (I don't know their frequency response but I'd bet it's not flat).

It would be great if you find a way to measure the intensity of the sound!
Apple pretends the threshold is 12 dB but if you hear the sound, it should be much, much higher than 12dB.
Would be great if you try to measure the dB value of it, even with one of those free Apps available for the iPad but of course much much better with a better noise recording device if possible!

I doubt it would be possible to really measure that. I have a real SPL meter but it can't measure anything below 40dBA so there's no point in even trying. Just handholding it will affect the measurement at those levels. Plus, even top-of-the-line meters can't measure much below 30dBA.

Also, Apple only specifies 12dBA at "operator position", which doesn't mean much (compared to e.g. "12dBA at 1m").

What I can say though is that the computer is inaudible from where I sit, except for that sound. Sometimes it's louder, and sometimes I can't hear it at all.

 

[Average Pro]

dB vz Hz

And when someone gets the equipment to measure the dBs, don't forget to also measure the Hz. Ask anyone in the music/recording industry and they'll tell you they've suffered hearing degradation. Mowing the lawn without hearing protection will degrade your ability to hear higher Hz. Fifteen years ago, I didn't wear hearing protection unless it was required.

Not taking both dB and Hz into account is like saying, "I have perfect vision, but I only see in black and white."

By the way, this is a great thread. I'm really hopeful someone can capture both. Also, I am curious if anyone who hears this sound is over the age of 30.

 

[Riwam]

It's not a very high frequency!

That's possible. Are there settings for this anywhere?



That could be the room or some of the spread-spectrum noise from the fan (the phone was directly over the nMP so it also picked up "wind" noise from the fan blowing air out). It could also be the phone's microphone/ADC amplifying those frequencies (I don't know their frequency response but I'd bet it's not flat).



I doubt it would be possible to really measure that. I have a real SPL meter but it can't measure anything below 40dBA so there's no point in even trying. Just handholding it will affect the measurement at those levels. Plus, even top-of-the-line meters can't measure much below 30dBA.

Also, Apple only specifies 12dBA at "operator position", which doesn't mean much (compared to e.g. "12dBA at 1m").

What I can say though is that the computer is inaudible from where I sit, except for that sound. Sometimes it's louder, and sometimes I can't hear it at all.

And when someone gets the equipment to measure the dBs, don't forget to also measure the Hz. Ask anyone in the music/recording industry and they'll tell you they've suffered hearing degradation. Mowing the lawn without hearing protection will degrade your ability to hear higher Hz. Fifteen years ago, I didn't wear hearing protection unless it was required.

Not taking both dB and Hz into account is like saying, "I have perfect vision, but I only see in black and white."

By the way, this is a great thread. I'm really hopeful someone can capture both. Also, I am curious if anyone who hears this sound is over the age of 30.

.........................................

I am sorry to disappoint those believing the sound of some nMP is a high frequency sound.
I could hear all the sound files in this forum with the noise made by different nMP.
I am 69 and a simple test showed me that my present limit is about 10KHz.
Therefore the annoying sound must be just a few KHz high.
Unfortunately humans are particularly sensitive to sounds in that part of the spectrum.
Therefore the noise does not need to be loud to be heard.
If the user has not a slave operating the computer at a distance, or is not a Gorilla with very very long arms, the nMP will have to be no further than about 1 meter from his ears.
Since this is the first MacPro built to be placed ON TOP OF THE TABLE instead of under it on the carpet, the need of a truly silent machine with all that power condensed in a small enclosure is vital.
Any continuous or intermittent noise is a BIG PROBLEM, not a minor nuisance!
Someone pointed here that even sensitive noise measuring devices begin registering noise at about 30dB.
Apple promised a threshold of 12 dB and that would mean a truly silent machine...if kept!
It seems however that not all the delivered nMP meet that standard...unfortunately.
Otherwise nobody would had any reason to complain about a noisy nMP.
Let's hope that Apple finds very soon a solution.

 

[ppxb]

A classical "Me, too" :-(

Hey, I'm 21 and own a nMP (

) since about one month. Connected is a Lacie Thunderbolt RAID System via Thunderbolt (TB), my Dell 2709 via TB (mDP), my Wacom Intuos4 L tablet via USB and a digital audio out cable. I didn't change anything regarding power supply or I/O configuration.

The whining sound was definitely NOT there from the beginning. I hear it now for about four days. With "idle" state it's about once a minute with a specific configuration I use I can get it to be permanent (I searched for such a solution in order to be able to reproduce it at my local ASP):

Open the OpenGL extension viewer, click on test section, choose multiple cubes and use the default parameters. Click on test.
At the same time open up Cinebench R15 and run a GPU test with it. Now the strange part: having Cinebench open as the FRONT window (that means the OpenGL extension viewer window is behind the cinebench window and completely hidden) the sound becomes permanent having the other apps window the front window almost makes no sound. Somehow crazy I assume.

Could you use that configuration, too, and post your results? Maybe it's not even related to that issue and a completely different sound ... but I really fear it isn't. The high whining sound drives me mad... :-(

 

[richard371]

I can really replicate it in photoshop using the blur filter. If I move the photoshop app more to the right of the screen it doesn't do it. Strange.

Hey, I'm 21 and own a nMP (Image) since about one month. Connected is a Lacie Thunderbolt RAID System via Thunderbolt (TB), my Dell 2709 via TB (mDP), my Wacom Intuos4 L tablet via USB and a digital audio out cable. I didn't change anything regarding power supply or I/O configuration.

The whining sound was definitely NOT there from the beginning. I hear it now for about four days. With "idle" state it's about once a minute with a specific configuration I use I can get it to be permanent (I searched for such a solution in order to be able to reproduce it at my local ASP):

Open the OpenGL extension viewer, click on test section, choose multiple cubes and use the default parameters. Click on test.
At the same time open up Cinebench R15 and run a GPU test with it. Now the strange part: having Cinebench open as the FRONT window (that means the OpenGL extension viewer window is behind the cinebench window and completely hidden) the sound becomes permanent having the other apps window the front window almost makes no sound. Somehow crazy I assume.

Could you use that configuration, too, and post your results? Maybe it's not even related to that issue and a completely different sound ... but I really fear it isn't. The high whining sound drives me mad... :-(

 

[ppxb]

Maybe another idea: Could the increase I noticed be connected to the Mac Pro 2.0 Firmware Update? Before I did this update there were NO problems. Might be a simple coincidence but maybe it's the reason. Who of you did this update too?

 

[ppxb]

Me again

This whining absolutely drives me crazy. I noticed something interesting as well with the aid of iStat Menus.

With annoying permanent noise (see my previous post about Cinebench et al.):

and without noise:

Do you notice the interesting increase regarding GPU 1 - Core Lowside? All other values are about the same. This value is three times higher. Is this correlation with Photoshop Blur as well noticeable?

 

[Riwam]

Congratulations for your effort!

This whining absolutely drives me crazy. I noticed something interesting as well with the aid of iStat Menus.

With annoying permanent noise (see my previous post about Cinebench et al.): Image

and without noise: Image

Do you notice the interesting increase regarding GPU 1 - Core Lowside? All other values are about the same. This value is three times higher. Is this correlation with Photoshop Blur as well noticeable?

......................................................................
I must congratulate you.
Finally someone is trying to find something, instead of either resigning or (worse) minimizing the noise problem.
I do not know if that points to the right direction but wouldn't be a good idea to contact the Apple customer help and ask them about this strange difference you found out, appearing to be related at least in time, to noise On an Off?
They should pass this info to a Senior and to the engineers building these machines.
Maybe you found something useful to solve this problem!
Anyway i admire people like you who fight against a problem instead of giving up.

 

[ppxb]

Thanks a lot for your very kind feedback!

To be honest, I was somehow thrilled when finding this little anomaly but now I fear it could be a simple (meaningless) coincidence...The problem is: The sound that comes regularly once or twice a minute for half a second seems not to have an influence on this specific described value (GPU 1 - Lowside). This could mean two things:

1.) There is no connection between my observation and the technical reason causing this issue for all of us who have (too) good ears
2.) The increase and decrease regarding this value is *that* fast that iStat Menus background task isn't even able to notice it because it happens within a period that is much too short to be noticed and displayed. I now set the update "frequency" from medium to fast and are waiting again for the next noise.

But I have to admit: It's some kind of disappointing anyhow. Paying 3k euros or more for a device that makes you wish to be partly deaf...

Remark: Today I called Apple and even talked to the escalation management within the technical division. They "don't know about this issue yet" *sigh*. I would have loved to have your Apple Care case numbers. Just to prove I am not the only one with this problem. They were extremely unfriendly and said the maximum they could do is sending me to a local ASP - but I shouldn't be too thrilled as the problem isn't even recognized and probably couldn't be corrected for this reason. Yeah... :-(

 

[impay]

it's so bad

ok first post. I feel like I'm migrating to following the "I just bough" thread...to this one...

I can hear the whine from about 3 feet away in a room with some moderate background noise from a road nearby. I'm 22 and have base 4 core model with upgrade to 16gb ram. I downloaded the update right away.

As far as I can tell with some dumb basic tests, the noise is consistent and at an equal volume whether idling or at extended >90% cpu loads.

Good thing is I can't hear it at all when I wear noise canceling headphones.

 

[tozz]

Thanks a lot for your very kind feedback!

To be honest, I was somehow thrilled when finding this little anomaly but now I fear it could be a simple (meaningless) coincidence...The problem is: The sound that comes regularly once or twice a minute for half a second seems not to have an influence on this specific described value (GPU 1 - Lowside). This could mean two things:

1.) There is no connection between my observation and the technical reason causing this issue for all of us who have (too) good ears
2.) The increase and decrease regarding this value is *that* fast that iStat Menus background task isn't even able to notice it because it happens within a period that is much too short to be noticed and displayed. I now set the update "frequency" from medium to fast and are waiting again for the next noise.

But I have to admit: It's some kind of disappointing anyhow. Paying 3k euros or more for a device that makes you wish to be partly deaf...

Remark: Today I called Apple and even talked to the escalation management within the technical division. They "don't know about this issue yet" *sigh*. I would have loved to have your Apple Care case numbers. Just to prove I am not the only one with this problem. They were extremely unfriendly and said the maximum they could do is sending me to a local ASP - but I shouldn't be too thrilled as the problem isn't even recognized and probably couldn't be corrected for this reason. Yeah... :-(

I actually sent an e-mail about this to tcook@apple and someone from Executive Relations called me two days ago, he sounded very serious about giving me a good experience, waiting for a callback today (he needed to talk with the engineers, like everyone else, seems like a popular position these days )

 

[Riwam]

The common elements to all noisy nMP...and if logic helps?

I actually sent an e-mail about this to tcook@apple and someone from Executive Relations called me two days ago, he sounded very serious about giving me a good experience, waiting for a callback today (he needed to talk with the engineers, like everyone else, seems like a popular position these days )

................................

Not being unfortunately any kind of computer expert, I do not know if logic can be applied to problems regarding computers.
Assuming that might be the case, we know from the different reports, that not all owners of a nMP hear any annoying noise, but this of course is a subjective element depending on the noise surrounding them and their auditive sensibility.

Then, those who DO hear it and are annoyed by it, have different configurations of nMP!

That would conduct us to the little probable conclusion that either all the 4 types of CPU, or all the 3 types of GPU, or all the 3 sizes of SSD, have a common bug, responsible on some nMPs for that annoying noise.
However "little probable" does not mean "impossible".

The other way to think about it is taking into account the FEW COMMON PARTS TO ALL nMPs.
As far as I know, besides the case, they are:
1) the single optimized fan
2) the logic board and it's connections to the panels with the CPU and the 2 GPU.
3) the power supply unit (PSU)

The fan, being the only moving part, would be easy to identify if faulty.
The logic board is, as far as I know, not commonly associated with noise problems, but as I acknowledged, I am by no means an expert!
PSUs however are often blamed for causing noises on PCs.
However, precisely for that very reason, Apple would have checked it when a nMP is returned for exchange, as several people in this forum report to have done, (although in some cases the new nMP had the same noise problem).

To sum up, if Apple still has not noticed that there is such a problem (as the unfriendly Apple employee pretended in one post in this thread, and in my opinion must be his personal ignorance instead of the actual situation regarding Apple) it remains that only Apple can gather a representative amount of nMPs of different configurations and check their common noise behavior with appropriate equipment under objective laboratory conditions.

Till that happens, users suffering from this problem can only resign (which I personally will not do once I receive my nMP in a month or so and if I do not get a 12dB noise threshold computer as advertised by Apple), or return their nMPs to Apple for exchange, and this as many times as necessary until they are satisfied with the nMP they receive, not a methodical approach and not a way to solve the problem but the only possibility in self defense.
Our customer's satisfaction is un undeniable right for every one of us since we do not get a nMP for free but must pay a lot of money (and wait a lot of time) to obtain one.

 

[ppxb]

I actually sent an e-mail about this to tcook@apple and someone from Executive Relations called me two days ago, he sounded very serious about giving me a good experience, waiting for a callback today (he needed to talk with the engineers, like everyone else, seems like a popular position these days )

I did this as well about 1,5 days ago. How long did they need in order to reply to you? I often had the impression they only respond to a very few people writing to this address ...

----------

................................
As far as I know, besides the case, they are:
1) the single optimized fan
2) the logic board and it's connections to the panels with the CPU and the 2 GPU.
3) the power supply unit (PSU)

I'm not a technical expert either but you could be right regarding your logic deduction. One point you might have missed is: The problem must come over time. With me the sound definitely wasn't there from the beginning. The first 30 days of usage were perfectly quiet without this "angry screaming cat" inside my nMP...

 

[Riwam]

The factor time is very interesting...as well as the cat!

I did this as well about 1,5 days ago. How long did they need in order to reply to you? I often had the impression they only respond to a very few people writing to this address ...

----------


I'm not a technical expert either but you could be right regarding your logic deduction. One point you might have missed is: The problem must come over time. With me the sound definitely wasn't there from the beginning. The first 30 days of usage were perfectly quiet without this "angry screaming cat" inside my nMP...

.....................................
Thank you for pointing to something I missed it: time.
This was because not every user complaining about the noise mentioned this time factor although most mentioned the "idle" condition against the "stress" one.
Strangely however one of them said the noise came while it was "idle"...but most said it happened while using a certain software and even detailed it.
I congratulate you for your interesting formulation of "a angry screaming cat".
The "coil whine" used by most people until now referred to something too closely related to an actual coil while we do not know at all the faulty component.
At least nobody will pretend the noise does not exist since no cat is included in the building process of a nMP.
You hit a point!

 

[tozz]

I did this as well about 1,5 days ago. How long did they need in order to reply to you? I often had the impression they only respond to a very few people writing to this address ...

2 days, sent the e-mail last Thursday, got the call this Monday. Impressive considering they redirected from some filtering process to the Swedish handler in that time too.

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I'm not a technical expert either but you could be right regarding your logic deduction. One point you might have missed is: The problem must come over time. With me the sound definitely wasn't there from the beginning. The first 30 days of usage were perfectly quiet without this "angry screaming cat" inside my nMP...

Coil whine can potentially happen over time, or disappear over time, so it's not unthinkable that it will come to affect more machines. Both mine had it from the second I booted them.

 

[Cubemmal]

I can hear the whine from about 3 feet away in a room with some moderate background noise from a road nearby ...

As far as I can tell with some dumb basic tests, the noise is consistent and at an equal volume whether idling or at extended >90% cpu loads.

That's a definite problem then, that should be looked in to.

 

[wildmac]

I did this as well about 1,5 days ago. How long did they need in order to reply to you? I often had the impression they only respond to a very few people writing to this address ...

----------


I'm not a technical expert either but you could be right regarding your logic deduction. One point you might have missed is: The problem must come over time. With me the sound definitely wasn't there from the beginning. The first 30 days of usage were perfectly quiet without this "angry screaming cat" inside my nMP...

It's a screaming cat now?

I'm still not hearing anything over the noise of the stream outside, my oMP, or the tinittus in my one ear..

 

[ppxb]

Coil whine can potentially happen over time, or disappear over time, so it's not unthinkable that it will come to affect more machines. Both mine had it from the second I booted them.

Interesting. I absolutely didn't know that (especially that it could also disappear after a specific time range).

Maybe the Executive Relations members only call customers with D500 upwards...who knows. ;-)

----------

It's a screaming cat now?

I'm still not hearing anything over the noise of the stream outside, my oMP, or the tinittus in my one ear..

At least when it is permanent. Then it's quite unbearable for me. I'm very sensitive to such kind of high noises. The fan sound itself is very pleasing and makes no problem to my view.

 

[antonis]

Coil whine can potentially happen over time, or disappear over time, so it's not unthinkable that it will come to affect more machines. Both mine had it from the second I booted them.

Is there any explanation of how it can disappear when it's initially there ? Sounds really strange issue.

 

[tozz]

Is there any explanation of how it can disappear when it's initially there ? Sounds really strange issue.

I'm not sure, but I think it has something to do with the heat generated. Don't quote me on it, I just have a vague memory that I read something about it.