Monday, May 13, 2013

More on Line Conditioning and Power Demands

I have owned an OPPO BDP-105 for several months now and I am continually impressed by its visual and sonic images (yes, I mean sonic images). Although my OPPO had a nasty firmware glitch, one that had to be corrected by returning the unit to the factory (argh!), all is well new in my home entertainment system.  I am pleased to report that a few minor additional changes to my rig has resolved some other annoying issues.

To provide some much-needed background, my darling wife is a stickler for parasitic power consumption (hates to leave things on that could otherwise be turned off) and our power conditioner turned out to be the rig's Master Switch.  However, powering down the rig in the correct sequence was a challenge for her to remember so we decided to do away with that and just compromise by leaving the system on continuously in whatever standby modes each piece of gear offered.  Most people understand that leaving your gear on improves thermal stability and this is what we first observed.  Things sound better right away and we do not have to wait the obligatory 30-60 minutes for the rig to warm up.

Another issue was caused by the huge number of power losses normally experienced in central Florida.  The power grid here is running at a capacity that pretty much exceeds its original design and, to compensate for the increased demand, transmission line voltages have been increased to their physical limits.  You can hear the huge ceramic insulators sizzle in high Florida humidity knowing that electricity is now flowing down them and into the ground rather than to its desired destination (apparently an acceptable loss to these infrastructure designers).  Raising the voltage on transformers not originally designed to operate at that level causes them to literally explode once thermal runaway begins (such as on hot days when there are a lot of air conditioners running and the heat-exchange efficiency is reduced on the cooling units for these transformers).  As a result, we lose power here a lot in dramatic fashion.  Without warning, thundering explosions echo through the treetops as substation transformers die in such spectacular fashion that even action moviemakers in Hollywood would envy.

The solution was a small pure sine wave UPS to power those electronics in the video portion of the rig that could withstand power interruptions for about 20 minutes without flattening the standby battery.  Moving the loads of these video components from the line conditioner to the UPS added capacity to the line conditioner for the audio components.  Much like overtaxing the power grid, my rig was taxing my line conditioner and splitting power in this way improved the audio playback quality.

What did I hear?  As you know if you have been reading any of my articles, I have a very dynamic system capable of huge transients and sudden surges of SPL.  What I heard was a distinct improvement in this attack where rim-shots on snare drums, explosions and gunfire, basically all of the starting moments in any instrument or sound effect were all greatly improved.  I attribute this to the additional power flowing through the line conditioner and primarily to the power amp.  Let me explain.

When you ask too much from your line conditioner, voltage levels sag and what was once 110V now becomes 108V or even worse.  Such voltage fluctuations result in non-linear power produced by any piece of gear attached to the line conditioner.  When the voltage drops at the line conditioner, the bias also changes slightly on the output devices and the distortion increases.  So not only do you get a power drop as demand goes up, you also get increased distortion because of these small bias changes.  When power supply exceeds power demand, you do not get this problem.

Think of it this way.  If you have a garden hose and want to fill a bucket, you can do a few things to fill the bucket quicker.  One is to use a larger garden hose and the other is to use a second garden hose.  There is only so much improvement in flow you can achieve by going to a bigger and bigger garden hose but as soon as you add a second hose you immediately reduce the time it takes to fill the bucket.  Adding the UPS to my rig was like adding a second garden hose.

Now there is a gotcha in adding the second power source and one that must be remembered.  You must always run all of the equipment in your rig off of the same electrical phase from your power panel (see my guide Extreme Audio 1: House Wiring for a complete explanation - a steal at 99 cents).  The connection of your "garden hoses" does not start at the wall outlet, it starts at the circuit breaker panel and you must plan to supply enough capacity to your system from there.

So there you have it, a brief walk through how to improve your system by properly designing adequate power capacity to operate your rig.  When playing your rig at loud levels and you notice that the sound deteriorates, I would suspect that the supply voltage at the outlet is dropping and you need to add more electrical capacity by adding a second power source (a second garden hose).

Yours for higher fidelity,

Philip Rastocny

I do not use ads in this blog to help support my efforts. If you like what you are reading, please remember to reciprocate, My newest title is called Where, oh Where did the Star of Bethlehem Go? It’s an astronomer’s look at what this celestial object may have been, who the "Wise Men" were, and where they came from. Written in an investigative journalism style, it targets one star that has never been considered before and builds a solid case for its candidacy.

My other titles include:

Copyright © 2015 by Philip Rastocny. All rights reserved.

No comments:

Post a Comment

To comment on this blog, you must first be a member. All comments are moderated.

Note: Only a member of this blog may post a comment.