or Connect
AVS › AVS Forum › Audio › Audio theory, Setup and Chat › USB DAC/Amp pop when mini fridge in same room turns on/off
New Posts  All Forums:Forum Nav:

USB DAC/Amp pop when mini fridge in same room turns on/off

post #1 of 19
Thread Starter 
Hey guys, I have been having this problem for some time now where when my mini fridge kicks on my speakers pop and the light on my HRT music streamer II dac either shuts off or flicks on and off. When the dac flicks on and off sometimes I'll hear a slight popping in the audio until I unplug it from the computer and wait a few seconds then plug it back in. Last year I had this problem in my previous apartment with my dac hooked up to my laptop using a denon stereo receiver; however this year I'm in a new apartment with a new desktop I built using a Dayton audio DTA-100a amplifier.

Last year I was able to run an extension cord from an outlet in a different room to my laptop and that fixed the problem however my computer now draws much more power and wouldn't be suited to run on an extension cord. I was looking into maybe getting some sort of UPS or line conditioner with automatic voltage regulation but I was looking for what you guys think would be best.
post #2 of 19
Quote:
Originally Posted by Hoovie59 View Post


Last year I was able to run an extension cord from an outlet in a different room to my laptop and that fixed the problem however my computer now draws much more power and wouldn't be suited to run on an extension cord.

How do you know that your computer uses that much more power?

If you obtain a Kill-A-Watt and actually measure it, I'll believe what you say based on that, but if you start talking about your 800 watt power supply I will remain skeptical.

It would take a lot of weird stuff to make a computer draw so much power that it couldn't be happy with a 12 gauge extension cord.

t would take a lot of weird stuff to make a computer draw so much power that it couldn't be happy with a 16 gauge extension cord, to tell the truth.
post #3 of 19
Quote:
Originally Posted by Hoovie59 View Post

Hey guys, I have been having this problem for some time now where when my mini fridge kicks on my speakers pop and the light on my HRT music streamer II dac either shuts off or flicks on and off. When the dac flicks on and off sometimes I'll hear a slight popping in the audio until I unplug it from the computer and wait a few seconds then plug it back in. Last year I had this problem in my previous apartment with my dac hooked up to my laptop using a denon stereo receiver; however this year I'm in a new apartment with a new desktop I built using a Dayton audio DTA-100a amplifier.

You probably have an $80 minifridge that is screwing up a DAC that cost you from $180 to $350 depending on which model Streamer you really have. Any fridge that generates that much EMI is a POS!

Frankly, if a mere small power line transient is causing the DAC lasting distress such that you have to power cycle it to restore normal operation, it is a bit of a POS itself.

One option is to simply get a minifridge that doesn't mess up the power like that.

Another option is to separate the fridge and its power cord and power source as much as you can from the audio gear.

It is possilbe that the pop is being picked up by the piece of coax that supplies it with a digital signal. You don't say how you connect the two so you are forcing me to speculate. TOSlink has wonderful rejection of EMI like what you are experiencing. If your PC lacks a toslink output, you can get a coax to toslnk adapator for less then $20 and when you use it minimize the length of the coax.
post #4 of 19
Thread Starter 
Its actually an 860 watt thank you wink.gif however you are correct, while it does draw more power from the wall than my laptop around 400 watts avg peak from the wall (measured from the power supplies internal voltage measurement); the main reason I really don't want to run an extension cord is the possibility of it becoming unplugged by one of my roommates.

Also while I appreciate the help if you could read as well as you speculate about what I have then you would see that I have the DAC hooked up via USB.
And with the EMI rejection; I thought it could be that as well so I bought a better usb cable with more shielding however it still doesn't make sense since the popping stopped last year when the fridge remained in the same space but the laptop was plugged in via an extension cord.

Last note, I'm a fourth year mechanical engineering student living off an internship budget so please be kind to my "POS" hardware.
post #5 of 19
Quote:
Originally Posted by Hoovie59 View Post

I have the DAC hooked up via USB.

USB is about the worst when it comes to EMI rejection.
Quote:
And with the EMI rejection; I thought it could be that as well so I bought a better usb cable with more shielding

The shielding can't address all of the possible sources of EMI. What makes coax and USB more EMI prone than Toslink is the fact that they are based on a metallic connection between the two pieces of equipment.while Toslink uses optical that is for all practical purposes invulnerable to EMI.
Quote:
However it still doesn't make sense since the popping stopped last year when the fridge remained in the same space but the laptop was plugged in via an extension cord.

I've never thought of a garden-variety extension cord as an EMI filter!

One possible approach might be to put an EMI filter on the power cord for the fridge.

Somethng like:

http://www.newegg.com/Product/Product.aspx?Item=N82E16882303042
Edited by arnyk - 11/4/13 at 9:32am
post #6 of 19
Thread Starter 
Unfortunately the HRT music streamer II only offers usb as an input or I would be using toslink. Thank you for the suggestion on the EMI filter, so you think it would be best to filter out to refrigerator as opposed to filtering the computer from it?

It just seems so weird that a usb peripheral device can be affected even though it has no external power supply and its not coming through the air via electromagnetic interference from the compressor. I think I'm going to run some tests to see if I can isolate the fridge and the computer and see if the problem persists. .
post #7 of 19
Quote:
Originally Posted by Hoovie59 View Post

Unfortunately the HRT music streamer II only offers usb as an input or I would be using toslink. Thank you for the suggestion on the EMI filter, so you think it would be best to filter out to refrigerator as opposed to filtering the computer from it?

I'd filter the source.
Quote:
It just seems so weird that a usb peripheral device can be affected even though it has no external power supply and its not coming through the air via electromagnetic interference from the compressor. I think I'm going to run some tests to see if I can isolate the fridge and the computer and see if the problem persists. .

Welcome to EMI! I used to get EMI on a turntable input from an AM station that was more than a mile away.
post #8 of 19
Quote:
Originally Posted by Hoovie59 View Post

you think it would be best to filter out to refrigerator as opposed to filtering the computer from it?

I agree with Arny that it's better to filter the fridge. The filter he linked to is probably okay, though I didn't see any specs for RF rejection. The filter shown in this article costs about $25 if you're up to sticking it in a plastic case yourself:

Hum and Buzz, Clicks and Pops

--Ethan
Edited by Ethan Winer - 11/6/13 at 10:43am
post #9 of 19
Another option might be to get a *powered* USB hub and put it in front of the Streamer. Buy it from a local store so you can return it if it doesn't cure the problem. The hub power supply may be more immune to power line noise.
post #10 of 19
Thread Starter 
@Ethan I'll take a look into that filter, I don't mind saving some money and project boxes are cheap anyway.

@Amirm I have been thinking about getting a powered usb hub because people seem to noticed increased sound quality using a powered hub as opposed to running off the computers usb ports.
post #11 of 19
Quote:
Originally Posted by Hoovie59 View Post

@Ethan I'll take a look into that filter, I don't mind saving some money and project boxes are cheap anyway.

One big source of power line filters for roll-your-own box projects like this is

http://www.jameco.com/webapp/wcs/stores/servlet/StoreCatalogDrillDownView?langId=-1&storeId=10001&catalogId=10001&categoryName=cat_3035&subCategoryName=Interconnects%20%2F%20Power%20Connectors%20%2F%20AC%20Power%20Line%20Filters&category=303512

You can get great power line filters for way under $10 which makes the price of the commercial boxed products look a little strange.

Warning! These roll-your-own filters involve lethal voltages (120 vac or 220 volt power line) and can literally blow up in your face if you don't know what you are doing. If you've been there,done that and got the tee shirt, not to worry so much! ;-) Just be careful!

One very inexpensive source of robust project boxes for a project like this is the electrical wiring aisle of your favorite hardware store or big-box home improvement store. Be sure that the box is connected to power line safety ground (third pin/green wire)
post #12 of 19
Thread Starter 
Thanks Arny, I didn't even think of turning this into a DIY project but I've done my fair share of small home wiring projects in the past so I'm pretty familiar with the feeling of grabbing on to that hot 110 wire someone forgot to turn off. I will definitely look into this as a solution, I just need to figure out the current draw from the fridge when the compressor kicks on.
post #13 of 19
Thread Starter 
Alright, Ethan I ordered on of the 10 amp RFI filters from that article. I have a short 3x12 extension cord I can splice it in to, I will follow up on how it works out.
post #14 of 19
^^^ Yes, please let us know how it goes. Arny is correct about working with power line voltages, but it's not that difficult to follow the Input and Output markings on the filter. biggrin.gif

--Ethan
post #15 of 19
Quote:
Originally Posted by Hoovie59 View Post


@Amirm I have been thinking about getting a powered usb hub because people seem to noticed increased sound quality using a powered hub as opposed to running off the computers USB ports.

Rule number 1 in audio is that someone, someplace is going to notice an improvement after making even the most improbable change. Remember green pens and CDs? Two words: sighted evaluations.

The specific claim is the usual mixed bag. Engineers play all sorts of games with USB power - some build devices that go over the top for power drain, and others cut back as much as possible on power supply available to USB ports, with laptops being a leading area of this kind of margin cutting.

So, is there someone someplace who plugged a power-hungry USB device into a power-starved USB port, and then moved to a more competent USB port on a hub and noticed a difference? Obviously yes. Are there USB hubs that are even more current starved than a laptop? Probably yes. Remember that USB power is limited by both the USB port itself and its power supply. So, plugging a USB hub into a 5 volt 40 amp power supply can be as futile as anything.

Is moving in a USB hub a long shot? Probably yes, and yes for sure if your PC is a desktop, and also yes for a well-designed laptop particularly if it is running off of AC power.
post #16 of 19
Thread Starter 
Quote:
Rule number 1 in audio is that someone, someplace is going to notice an improvement after making even the most improbable change.

Yeah I don't even know if I'd be able to notice a difference on my Energy RC-10s as much as I love those little guys for the money. This would solely be for a test that's why I would buy the usb hub at a local shop so I can return it if I hear nothing different.
Quote:
The specific claim is the usual mixed bag. Engineers play all sorts of games with USB power - some build devices that go over the top for power drain, and others cut back as much as possible on power supply available to USB ports, with laptops being a leading area of this kind of margin cutting.

Yeah I know most of my usb ports on my motherboard are rated at 5v ~1A with one being a charging port running at 5v ~1.5A for charging tablets and such. I have hooked my DAC up to the charging port before but have not done any critical listening comparing between the two so I guess I could always start with that and then go from there.
post #17 of 19
I wonder if this could be other than a transient spike, as in a cycle or two, but more like a short term brown out, as in a second or two. In other words it's causing a temporary low voltage condition, enough so that components are changing their state.

In residential situations compressors are guilty of the biggest percent of current increase at turn on. This is especially true with 120 volt devices impacting one phase of your breaker panel. You might try plugging that fridge into a receptacle that is on the opposite phase.

Like others, when you find the solution, I would like to hear what it is.
post #18 of 19
Thread Starter 
Alright, so I got the EMI/RFI filter installed and that seems to have fixed the problem. I can plug either my computer into it or the fridge and I still get no popping, even when the computer and the fridge are plugged into the same outlet. I have only been testing it for a little under 24 hours so I'll let you know if anything changes but for now it seems to have fixed the problem. So thank you guys for the help, I appreciate it especially since it saved me a considerable amount of money as opposed to buying an expensive brand name filter.
post #19 of 19
Excellent! Thanks for letting us know.

--Ethan
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Audio theory, Setup and Chat
AVS › AVS Forum › Audio › Audio theory, Setup and Chat › USB DAC/Amp pop when mini fridge in same room turns on/off