Personal computing discussed

Moderators: Captain Ned, emkubed

 
setaG_lliB
Gerbil First Class
Topic Author
Posts: 135
Joined: Wed Mar 03, 2010 6:02 pm

Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 3:41 pm

The last two weeks have been cold, around -20 to -35C. The furnace is getting quite a workout and just sucking the moisture out of the air. Humidity is sitting at 20%, and I'm getting zapped by every metal object I touch.

Last week, my five year old Marantz receiver started sending a loud POP to the front left speaker upon startup. It's just a single pop, and the sound quality out of that channel hasn't been affected (yet). However, it's a pretty loud pop, which I can't imagine is very good for the speaker.

There are two relays inside the receiver that click when it's first turned on. The first click is the power supply coming on, and I believe the second one is the amplifier switching out of protected mode. The pop always occurs immediately after the second relay click.

Anyway, the recent thread about humidifiers had me wondering if the extremely dry air might have anything to do with it. Of course our long, cold and dry winters haven't been an issue before, so I dunno. What do y'all think? Coincidence?
 
kvndoom
Silver subscriber
Minister of Gerbil Affairs
Posts: 2743
Joined: Sat Feb 28, 2004 11:47 pm
Location: Communistwealth of Virginia

Re: Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 3:49 pm

The relay is supposed to delay connection to the speakers until the initial surge has run its course. I don't think i'ts humidity related, personally.

Is it feasible to just leave the receiver on at all times? Standby wattage shouldn't be too bad and there's less risk to your speakers.
A most unfortunate, Freudian, double entendre is that hotel named "Budget Inn."
 
The Egg
Gold subscriber
Minister of Gerbil Affairs
Posts: 2557
Joined: Sun Apr 06, 2008 4:46 pm

Re: Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 5:09 pm

I've never heard of electronics having issues just from low humidity itself. Of course I don't know everything, but I would expect it to be much more a topic of conversation for spaceflight (where there's not only no humidity, but also zero atmosphere) and desert environments. I don't recall once hearing low humidity mentioned.

Of course large static discharges can cause damage; hopefully this isn't what happened. I also have low humidity and lots of static in my place due to underfloor heating and carpets. Invest in a humidifier and always remember to frequently discharge.
 
Wirko
Gold subscriber
Gerbil First Class
Posts: 172
Joined: Fri Jun 15, 2007 4:38 am
Location: Central Europe

Re: Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 5:34 pm

Well, the loud "POP" is a pretty sure symptom of DC voltage at the output. Check it with a voltmeter. If you don't have one at hand, disconnect and then reconnect one of the speaker wires while the receiver is in operation (and take care to keep that wire away from other electrical contacts and receiver housing). If you hear the same pop again then it's DC voltage. It's probably not very large or it would already have triggered the DC protection in the amplifier. However, it may be a sign of a greater failure that's coming.

As for humidity ... if an electrical component is already failing then a big change in temperature or humidity could do additional harm.
 
Waco
Gold subscriber
Minister of Gerbil Affairs
Posts: 2731
Joined: Tue Jan 20, 2009 4:14 pm
Location: Los Alamos, NM

Re: Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 5:50 pm

My house sits at 15-30% humidity pretty much constantly. Static can be an issue, but I doubt that's what's causing the pops you're hearing (unless you don't have the receiver grounded?). Dried out caps, on the other hand, could be.

I wouldn't worry about it too much. If it starts to get worse, it's possible the receiver is on the way out anyway, but it is unlikely that the cause is low humidity directly IMO.
Desktop: Z170A Gaming Pro Carbon | 6700K @ 4.4 | 32 GB | Radeon VII | XSPC RX360 | Heatkiller R3 | Samsung 4K 40" | 2048 + 240 + LSI 9207-8i (128x8) SSD
NAS: 1950X | Designare EX | 32 GB ECC | 7x8 TB RAIDZ2 | 8x2 TB RAID10 | FreeNAS | ZFS | LSI SAS
 
DancinJack
Maximum Gerbil
Posts: 4351
Joined: Sat Nov 25, 2006 3:21 pm
Location: Kansas

Re: Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 5:59 pm

Waco wrote:
My house sits at 15-30% humidity pretty much constantly. Static can be an issue, but I doubt that's what's causing the pops you're hearing (unless you don't have the receiver grounded?). Dried out caps, on the other hand, could be.

I wouldn't worry about it too much. If it starts to get worse, it's possible the receiver is on the way out anyway, but it is unlikely that the cause is low humidity directly IMO.

I'll echo this. My house is generally 20-35% depending on the season. I also wouldn't worry too much unless something happens.
i7 6700K - Z170 - 16GiB DDR4 - GTX 1080 - 512GB SSD - 256GB SSD - 500GB SSD - 3TB HDD- 27" IPS G-sync - Win10 Pro x64 - Ubuntu/Mint x64 :: 2015 13" rMBP Sierra :: Canon EOS 80D/Sony RX100
 
ludi
Gold subscriber
Lord High Gerbil
Posts: 8254
Joined: Fri Jun 21, 2002 10:47 pm
Location: Sunny Colorado front range

Re: Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 6:24 pm

setaG_lliB wrote:
Last week, my five year old Marantz receiver started sending a loud POP to the front left speaker upon startup. It's just a single pop, and the sound quality out of that channel hasn't been affected (yet). However, it's a pretty loud pop, which I can't imagine is very good for the speaker.

It isn't. As wirko noted above, it means there's some DC offset floating on that channel when the relay closes, which can crash the speaker voicecoil if it gets bad enough. Moreover, that offset might still be there during normal operation, heating the voicecoil in the speaker. If it were me I would pull that receiver from service immediately before the eventual cascade failure occurs, and begin a repair investigation.
Abacus Model 2.5 | Quad-Row FX with 256 Cherry Red Slider Beads | Applewood Frame | Water Cooling by Brita Filtration
 
just brew it!
Gold subscriber
Administrator
Posts: 52436
Joined: Tue Aug 20, 2002 10:51 pm
Location: Somewhere, having a beer

Re: Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 6:53 pm

Unless the "pop" coincides with you touching the receiver I doubt it is a static electricity issue.

A few years ago I fried a keyboard, but that was a massive spark jumping from my fingertip into the keyboard right after taking off my coat (so I was really charged up).
Nostalgia isn't what it used to be.
 
setaG_lliB
Gerbil First Class
Topic Author
Posts: 135
Joined: Wed Mar 03, 2010 6:02 pm

Re: Low humidity and electronics (in this case, AV receivers)

Mon Feb 18, 2019 9:34 pm

So I tried disconnecting and reconnecting the speaker while the receiver was on and didn't hear anything unusual.

However I noticed something interesting. When the receiver is connected to a silent source, the loud bang doesn't occur immediately. The amplifier relay will close, but the left speaker doesn't go POP until 3-10 seconds later. However, when the receiver is connected to an active source (eg, radio tuner or cable box), the speaker pops immediately after the relay closes.

Are the surround channels on these newer receivers equal in quality to the front channels? I still have an old Sony Pro-Logic receiver from the early 90s that outputs 110 watts to the front channels, but only 40 wpc to the surrounds. Now, Marantz claims that each channel on this model can output 100 W, so I'm assuming that they've used identical amp ICs for each channel? My grand plan is to connect my front speakers to the currently unused Rear Surround outputs. Pretty sure I saw an option to remap speakers in the setup menu.
 
notfred
Maximum Gerbil
Posts: 4559
Joined: Tue Aug 10, 2004 10:10 am
Location: Ottawa, Canada

Re: Low humidity and electronics (in this case, AV receivers)

Tue Feb 19, 2019 9:02 am

I suspect that you have a dead chip or transistor somewhere in the circuit. It possibly got fried by the static from low humidity, or it could just have been a normal failure.

You need to get this fixed before it destroys your speakers.
 
Waco
Gold subscriber
Minister of Gerbil Affairs
Posts: 2731
Joined: Tue Jan 20, 2009 4:14 pm
Location: Los Alamos, NM

Re: Low humidity and electronics (in this case, AV receivers)

Tue Feb 19, 2019 11:04 am

Unless you have very stout speakers pops like that can be pretty damaging. My old Hafler power amp did the same thing when the main supply caps were dried out (granted, it was also 30 years old at the time) - it would push the woofers on my towers out a good 3/4" before settling down.

If you can remap the outputs it's probably worth checking the specs - the rear channels might be reduced power but potentially still more than enough for your normal listening levels.
Desktop: Z170A Gaming Pro Carbon | 6700K @ 4.4 | 32 GB | Radeon VII | XSPC RX360 | Heatkiller R3 | Samsung 4K 40" | 2048 + 240 + LSI 9207-8i (128x8) SSD
NAS: 1950X | Designare EX | 32 GB ECC | 7x8 TB RAIDZ2 | 8x2 TB RAID10 | FreeNAS | ZFS | LSI SAS
 
setaG_lliB
Gerbil First Class
Topic Author
Posts: 135
Joined: Wed Mar 03, 2010 6:02 pm

Re: Low humidity and electronics (in this case, AV receivers)

Tue Feb 19, 2019 1:38 pm

I'll open it up and take a look at the caps today. It's a little disheartening that Marantz is using cheap caps and/or not cooling their products adequately. This thing runs much hotter than my Sony and Denon (I know Denon and Marantz are built in the same factory, but the Denon at least has a couple of fans under the amp sinks). Marantz used to be the crème de la crème!

My old Sony Pro-Logic receiver from 1991 is on its original caps and still going strong as a retro games console/computer amp. And early Dolby receivers weren't exactly high quality products, at least when compared to the stereo-only stuff of the day.

/rant
 
ludi
Gold subscriber
Lord High Gerbil
Posts: 8254
Joined: Fri Jun 21, 2002 10:47 pm
Location: Sunny Colorado front range

Re: Low humidity and electronics (in this case, AV receivers)

Tue Feb 19, 2019 1:49 pm

setaG_lliB wrote:
I'll open it up and take a look at the caps today. It's a little disheartening that Marantz is using cheap caps and/or not cooling their products adequately. This thing runs much hotter than my Sony and Denon (I know Denon and Marantz are built in the same factory, but the Denon at least has a couple of fans under the amp sinks). Marantz used to be the crème de la crème!

My old Sony Pro-Logic receiver from 1991 is on its original caps and still going strong as a retro games console/computer amp. And early Dolby receivers weren't exactly high quality products, at least when compared to the stereo-only stuff of the day.

/rant

I don't want fans humming in the background. I want the vendor to use enough heatsink and airflow space to cool passively. So far I've not found a Yamaha that wasn't well designed although I haven't shopped their offerings in the past 4-5 years.

In my experience, stereo receivers usually do better because people expect a home A/V equipment footprint that's typically far too large for a 2-channel unit and a bit too small for a multi-channel unit, meaning you end up with a cyberpunk diorama of either rural America or the Kowloon Walled City. The latter isn't great for heat dissipation.
Abacus Model 2.5 | Quad-Row FX with 256 Cherry Red Slider Beads | Applewood Frame | Water Cooling by Brita Filtration

Who is online

Users browsing this forum: No registered users and 9 guests