Axiom Home Page Forums General Discussion Home Theater Do I need a power conditioner?

I have a question reguarding the power source for a home theatre. As it is, I have, plugged into the same power bar, a Denon 1602, Ep125, JVC DVD player, and Sony TV. Sometimes, when I am listening to music or watching a movie, and I shut the sub off or turn it on, it causes a huge 'click' sound out of all the speakers like as if a power spike might have gone through. The TV picture will also wave a little. This happens almost always when I switch the sub on or off, but has happened once or twice when switching the tv on or off.
The plug the power bar is plugged into is grounded.

Do I simple need a better power bar or do I need a power conditioner because of the amount of things I have plugged into it? I was recommeded by a fellow computer technician to use a UPS, but those are a few hundred dollars, and I don't want to spend that much.

does anyone have any less expensive suggestions, or just any suggestions at all?

Thanks!

Hi Ravi,
I don't think you need to spend your money on a power conditioner. What you might want to try is (1) pluging your TV into a different source and (2) turning the vulume all the way down on your speaker source as well as your sub before turning them off or on this will eliminate the pop or cracking noise that you hear.

CAV104

ravi,

I am not too sure if a power conditioner will solve your problem (usually wanted/needed to clean up "dirty" power sources). And going to a UPS would be a bit of overkill (and probably expensive), I believe. Using a UPS is a good idea on a PC to protect valuable data, but is really not needed for your HT system.

What IS needed is a good quality Power strip with surge supressor - to protect your equipment against power surges (often caused by lightning strikes). A good one could cost $30 - $50 and have a joule rating somewhere around 15K - 20K (as I remember, but I'm not 100% sure about the numbers). As I calculate it, unless your TV is a big projection unit, you receiver and sub are the largest current demand devices. To see what the total load is on the outlet you have the power strip plugged into, look on the back of all the items and either add up all of the watt ratings, and then divide by the voltage (115V or so) to get the amps - or if they all have amp ratings, just add them up. Your outlet is likely to be on a circuit rated at 12 - 16 amps. You need to ensure that ALL appliances connected to that circuit don't exceed the rated capacity (you can check your breaker or fuse box to confirm the rating). So much for the quick electrical lesson.

The problem(s) that you are experiencing could have one of several causes. Faulty switch(s), faulty grounding, poor electronics/filters in the power supply, sensitivity to RF, overloaded circuits, among others. (I would love to have BBIBH's help here!) One thing you can try is to find a separate power circuit to plug the sub (and or the receiver)into - so the initial electrical load (when you turn it on) happens on a different circuit. Actually the problems you are describing are pretty common, especially on some homes where the wiring is 14 gage as opposed to 12 gage.

One more suggestion - many electrical connectors have polarized spade plugs - even if they dont have a separate ground. If they don't have the polarized spade, try unplugging it, rotate 180 degrees and plug it back in.
This can often eliminate hum and spike noise.

Good luck - and let us know how it turns out.

Randyman

I'm wondering why you feel the need to turn off your sub in the first place, which, if I've read your post correctly, appears to be the source of your problem. As the EP-125 has auto-sensing circuitry, why turn it off at all? After a period of time in which your sub is not sent a signal from the receiver or pre-amp (i.e. around 20 minutes, and you've been listening to music in two-channels, speakers set to large), the sub will go to sleep, or power down, and won't make a peep until it receives the next signal, as in the next time you're watching a DVD in a 5.1, 6.1 or 7.1 format, or using a multi-channel audio format (DVD-A, or SACD). I've owned an EP-175 for about two and a half years now and I never turn it off, though it is often in an inactive state, awaiting the next signal, and I experience none of the difficulties you describe.
My apologies if I've misunderstood your post, and best of luck, sir. Cheers!

DS.

I can sympathize with your situation Ravi, but not to your extreme. I have a midrange shelf system connected to my PC so i can play MP3s on it, but when i turn it off (i have to turn it off because it is in my bedroom and the light is annoying) it makes a loud pop on my regular computer speakers, i have a nice surge protector from a reputable company rated at 1600 joules, BTW this is plenty anything above about 1100 is plenty so i know its not the surge protector. i have found that the only real solution to the "pop" is to turn my computer speakers all the way down before i turn off the shelf system. on a side note thought, make sure that if there is an extention cord in your setup anywhere that it is rated in amps above what your circuit braker is rated (in the U.S. most are rated at 12, 15 or 20 amps depending on what your electrician did). I'm sorry after all this rambling that i haven't supplied a real solution but if you do fix the problem would you post your solution for those of us that haven't been able to figure it out.
Kore

Thanks for all your replies everyone!

I have a real el-cheapo 5$ power strip, so I think I'll buy a new one. Does anyone here use a power conditioner? I'm wondering if it actually does improve sound quality.

Dave, there are two reasons for shutting my sub off.
1) it makes a real annoying humming sound when it is in the auto off mode.
2) sometimes I am watching or listening very late at night, and past 11pm where I live, people can call the cops if there's too much volume. So, to be safe from being evicted, I turn the sub off.

Hi Ravi,

Lots of good advice from Randyman, Dave, and others. But first, I'll address the power "conditioner" question. No, in my judgement, power conditioners rank right up there with expensive exotic cable in the scam territory. They make absolutely no difference to sound quality, nor should they. Yet naive audiophiles, trying to improve the admittedly flawed illusion of stereo and home theater, will spend hundreds of dollars on power conditioners. Of course, if you believe strongly enough, perhaps you'll hear a difference, just like the gullible townspeople seeing the emperor's new clothes (when he had none).

Any competent engineer designs the power supply of your amp or receiver to filter and transform the AC power from your wall outlet to the appropriate voltages to power the circuits in the amp and receiver. No further power "conditioning" is necessary.

Now, to avoid those large pops (capacitors discharging in amps and receivers) in the future, here's the sequence to follow in powering up or powering down all your gear:

Turn on the AMP or RECEIVER LAST, after you've turned on all your other components, including the subwoofer, which should be the second to last turned on (because it contains a power amplifier).

TURN OFF your RECEIVER FIRST, then your SUBWOOFER, then your TV and all the other components.

If you follow this sequence, you won't have pops again.
I'll deal with your subwoofer hum problems in a later post. I'm certain it's a ground loop.

Regards,

Thanks for the replies everyone

I figured a power conditioner wouldn't make the sound any better. Power cords probably don't help much either.

I will buy a decent surge protector, and see if that helps.

thanks again!

ok. Alan had been very explicit in the useness of power conditioners. I do have a power conditioner. It is a Monster HTS800. It is the cheapest one from Monster but it is very good. I bought it because I have some real problems with power in my house and I want some insurance for my equipment. I can say that really there are no audible diferences with the Power Conditioner but... there are really some clear video diferences with it. Also it helps in color coding all of your component cables. Another thing tht worried me was taht I got DirectTV and here in Puerto Rico were I lived there are a lot of thunderstorms. In the Monster, you plug alll the coaxial and phone lines so everything is protected; and it only cost $75 and they gave some thousands of equipment in insurance if something ever happened. I think it is a good buy and addition to any home theater... my 2 cents.

Hi Fallo,

You're correct that power conditioners can help eliminate video artifacts (banding, lines that creap vertically up or down the screen and the like) because problems like those often orginate in the megahertz range (millions of Hz), which is why video is affected.

I was speaking of power conditioners' lack of benefits in the audio frequency region (20 Hz - 20 kHz). Thanks for pointing out the practical benefits as well.

Regards,