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Musings on Switching Power Supplies (LPS for Oppo / DirecTV/ Radiance)

So, this whole story begins about a couple months ago when I was watching a satellite television show on my HT system.  While I was watching, I noticed that my Oppo bluray player was still on (I often turn everything on in the beginning to warm stuff up and/or listen to music).  Well, I hit the remote button to turn off the Oppo and a weird thing happened.  The sound got a little bit better.  It lost a small bit of that digital “solid-state” harshness / brightness.  I then thought, “wait a minute, something is going on here”.  The next thing I did was, even though my Oppo was powered off in “stand-by” mode, I went and just unplugged it completely.  The sound actually got a tiny bit better after that.  Now I have read postings that say switching power supplies can cause noise in other devices when they share the same circuit/outlet.  I never really gave it much thought, but apparently this is definitely a thing.  My Oppo is plugged into the same outlet as me left surround amp, which is a completely different circuit than my HT processor and other amps.  However, the switching power supply in my Oppo BDP-103 was still causing havoc in the system!

I have four dedicated 20 amp circuits for my HT equipment.  I also had two other devices that still contain switching power supplies:  DirecTV Genie satellite receiver and a Lumagen Radiance video processor.  My DirecTV was plugged into the right surround outlet and the Radiance was plugged into the same outlet as my Krell S1200 HT processor.  So the next step was to pull those out and connect them to regular house outlets (which are different circuits and not even in the same subpanel).  I could see immediately that I lost some of the video quality through HDMI.  The picture was not as sharp and it introduce a little bit of noise into the image.  However, it did improve the sound even more (got rid of more of that digital harshness).

So what to do next?  Well, of course get rid of all these switching power supplies and, somehow, implement linear power supplies!

auxinput

Showing 3 responses by nonoise

nonoise's avatar
nonoise
11,226 posts
 
Although this is a bit off topic, it still deals with digital noise, and what I'd like to add is to get a very good HDMI cable for viewing. 

I just swapped out a generic, though highly rated, HDMI cable that you can get on Amazon for about $20 and inserted a WireWorld Chroma 7 HDMI cable and it's in another league. Not incremental to anyone with a good set of peepers but Yuuuge. I see now why they say politics is for people too ugly for Hollywood. All the pores and blemishes stand out now. 

Ugh.

Being a news junkie the first thing I noticed is the chyron at the bottom of the screen and how sharp it is along with the scrolling type. Clothing has amazing detail as well. What really surprised me was the catch light in the hosts eyes. You can clearly see the three different spot lights from above reflected in her eyes. And the three fluorescent lights from inside her desk show up individually in her cornea and the whites of her eyes as rectangular. Quite impressive.

The rep at The Cable Co. told me that the 7 series has better insulation than the 6 series and you can consider each line of the 7 to be the equivalent of the next higher line in the 6. Whatever it is, the digital noise is gone from the screen. My plasma used to have that somewhat soft focus compared to a newer LED screen but now it's very competitive, if not their equal. Colors are better saturated and blacks are deeper with finer gradations. I may just put off getting that new OLED but I still can't stand the heat coming off the set.

Tonight I'm going to watch and see what the WireWorld Ultraviolet 7 HDMI does for my blu-ray viewing. It should be nice.

All the best,
Nonoise
nonoise's avatar
nonoise
11,226 posts
 
The only thing that's keeping me from splurging on a LPM for my OPPO is the results that Dan got over at Modwright. He tried to come up with one himself and it wasn't worth the hassle. He claimed it ran way too hot so he got one of Mr. Lee's unit (like the one that auxinput has) and found it to be good, but still too hot for his tastes.

He says he got very little in the way of measurable differences between the SMPS and the LPM units but that could be written off as sour grapes since auxinout says the LPM unit has started to cool off as it broke in.

The one work around that I"ve done before is to take the upper lid to a shop and have them drill some holes in it to aid in ventilation. You can also go further and carefully have some vent holes drilled in the bottom of the unit for better air flow but just doing the lid top should be good enough.

All the best,
Nonoise
nonoise's avatar
nonoise
11,226 posts
 
@auxinput, I'm beginning to think you can read my mind lately. 🤔

I wanted to go the same route as you with a replacement LPM power unit for my OPPO 103 but Funjoe over at Clones Audio only makes them for the 205 series. The SE unit from that eBay site is supposed to run cooler than their standard version but I went with the Furutech IEC inlet with the Mundorf wiring and that made an appreciable difference so I left it at that. Here is the site if anyone is interested. I'm sure someone with better skills than me can build it for less. 👍

Since I'm only using the OPPO for movie watching, I contacted OPPO and asked their opinion on whether or not the newer line of 4K blu-ray players will out perform my old 103 if I forgo 4K and stick to standard blu-ray and they told me no, keep your 103. So, maybe someday I'll look into that SE LPM unit in the future.

Thanks for your pioneering spirit and all the best,
Nonoise
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