View Full Version : Keeping HDMI Connectors Clean


HiFiFun
05-29-09, 04:25 PM
Over the years I've been a proponent of keeping metal contacts clean as debris and oxidation can degrade sound and picture quality.
In a recent case I moved the XLR audio connectors around (with gain up and no-signal) and could hear a crackling noise. It was either a loose connection or oxidation. It wasn’t a loose connection!
So who stores cables with the ends exposed or throws them on the carpet?
In a second case cleaning my HDMI connectors resulting in an improvement in my picture quality. My screen had a slight yellow bias and did not look good at high brightness levels (30-40ft-l).
But usually it’s best to leave well-enough alone? (Especially for the tiny HDMI connectors). Not really as dust and very thin coats of oxidation are all too easy to contaminate.
So what is safe to gently clean but not destroy?
I successfully used QD Contact Cleaner followed by 2-26. Both CRC products are sold at Home Depot. I turn power off, and then open the doors for the contact cleaner squirts. It not that bad but better to be safe as it is flammable. I wait ~3 minutes then use the 2-26 lubricant (which seals and improves electrical properties.)
It’s easy to use too much of the 2-26 but it has a very benign composition.

I kept the cables unplugged on for a few minutes and then connected them to avoid reintroducing new contamination. In the end I treated every electrical connection. I noticed an improvement in picture fidelity over a three day period as the lubricant slowly evaporated.
Note: I’m not recommending anything here: just sharing my experience. All for $11.

HiFiFun
05-29-09, 04:31 PM
http://www.crcindustries.com/ei/content/prod_detail.aspx?S=Y&PN=02130
http://www.crcindustries.com/ei/content/prod_detail.aspx?PN=02004&S=Y
http://www.crcindustries.com/catalog/images/Cleaners%20and%20Degreasers/02130.jpg
http://www.crcindustries.com/catalog/images/Lubricant%20and%20Penetrant/02004.jpg

HiFiFun
06-10-09, 08:58 AM
It's now been several weeks since I’ve cleaned and protected every electrical contact: HDMI, A/C power, speakers, XLR, TRS and RCA pin in my system. I'm observing the best and most consistent audio and visual fidelity ever. Because of the clean and stable contacts I've made more fine-tuning progress than ever before.

But first here is a hilarious, ironic or sad finding depending on ones perspective:
Most reviewers over the decades are actually hearing diode effects of unoptimized electrical contacts. An untreated/protected contact will deteriorate over time. Plugging in new cables can sound better because they are clean and break through the very thin film, of contamination, oxidation or finger oils. It’s a vicious cycle which has lead generations of consumers on a never-ending upgrade path. Reviewers concluded that (especially PCM) digital sounded terrible. The industry went on wild goose chases such as SACD.

Here is what I’ve found is important:
Bi-amping all of my 5.1 speakers made a large difference in clarity and overall fidelity.

Always unplug the power from the wall for the entire system and reboot at least once a week (and after power interruptions) to remove any subtle degradations. Gear does suffer faults for this any many reasons until rebooted.

High power amplifiers should be plugged directly into the wall. Or even better plug'em into a Furman Power Factor Pro.

As a result advanced surround sound modes like Circle Sound II now have the same tonal quality and spectrum as in regular stereo. You want headphone effect from the back channels? You got it!

Other contact cleaners (like MDG) or not recommended as they did damage one on my HDMI contacts.

Monoprice cables are recommended. Monster Cable (especially the time-windings) are not as they do not sound natural.

If you sort through all the decades of mis-information and ignorance then this is what really matters to achieve consistent high fidelity. :)

PooperScooper
06-10-09, 11:01 AM
In a second case cleaning my HDMI connectors resulting in an improvement in my picture quality. My screen had a slight yellow bias and did not look good at high brightness levels (30-40ft-l). Can't happen.

larry

ccotenj
06-10-09, 12:09 PM
Can't happen.

larry

+1...

some of the "follow up items" fall into that category as well...

crutschow
06-10-09, 06:37 PM
As has been noted umpteen times (at least) by many, digital signals, such as HDMI and digital audio, do not subtly degrade. They either work perfectly or very badly. Effects such as "slight yellow bias" or "looks bad at high brightness levels", which can occur in analog systems, can not be caused by bad contacts in a digital system. The nature of digital signal processing precludes such effects.

If you believe otherwise than you do not understand digital systems and are the one pursuing a "wild goose chase".

PooperScooper
06-12-09, 10:44 AM
Well at least he was only out the price of a can of contact cleaner. Not a $300 1m HDMI. cable.

larry

Taldir
06-15-09, 09:02 AM
I would not even attempt to clean them. If they manage to get that dirty you may just want to buy a new cable!

mrgeekguy
06-16-09, 05:59 PM
I would not even attempt to clean them. If they manage to get that dirty you may just want to buy a new cable!

I'd go case by case, but if oxidation is big problem, it probably not a great cable to begin with, best to toss it.