Insufficient Power Conditioning?

[Grainger49]

Andrew,

So, no noise till you turn on the outside lights.  Then pulsing and it continues even after the lights are turned off.  Sounds like some oscillation is set up.  But usually oscillation is high frequencies. 

I think the type of lights you DO have will deepen the mystery.  Dan (Doc) expected something that normally generates noise like Quartz or LED.

Is there anything else on the outside light circuit other than the incandescent lights?

Do you have the BeePre input selected shorted?

 

[Doc B]

You might try measuring the wall outlet voltage while you turn the lights on to see if there is a significant change. Are the lights just connected to a regular switch, or is there maybe a motion detector circuit or a timer or something else incorporated with the lights?

 

[ALRubinger]

So, no noise till you turn on the outside lights.  Then pulsing and it continues even after the lights are turned off.  Sounds like some oscillation is set up.  But usually oscillation is high frequencies. 

Actually, there is a hum there without the lights that this particular recording didn't pick up so well; sometimes it's much louder.

I think the type of lights you DO have will deepen the mystery.  Dan (Doc) expected something that normally generates noise like Quartz or LED.

Just incandescent.

Is there anything else on the outside light circuit other than the incandescent lights?

Yep: the LED television (which when on can also increase the humming volume) and other misc A/V things.

Do you have the BeePre input selected shorted?

I'm not sure what this means?  The buzzing is not affected by the BeePre input selector, balance, or volume pots.

S,
ALR

 

[ALRubinger]

You might try measuring the wall outlet voltage while you turn the lights on to see if there is a significant change. Are the lights just connected to a regular switch, or is there maybe a motion detector circuit or a timer or something else incorporated with the lights?

Yeah, turning on anything else on that circuit will drop the voltage a bit.  At rest, 118V.  With outdoor lights on, 115V.  With outdoor lights, amp and preamp all on, 114V.  Measurements taken from the leads on the power input of the BeePre.

 

[Doc B]

Are those voltages measured with the Tripplite in the circuit?

 

[ALRubinger]

Are those voltages measured with the Tripplite in the circuit?

Yup.

Worth noting; the TrippLite apparently doesn't isolate the neutral output, only the hot:

Amazon review: "Unfortunately this product has the output neutral line tied to ground"

S,
ALR

 

[Grainger49]

Andrew,

You had said that there was hum but the laptop speakers didn't produce it. 

Many digital devices put noise onto the ac line.  The isolation transformer will give you isolation but not eliminate it.

A selected open input can pick up noise.  So for testing you take jumpers and jump the right hot to the right ground, the left hot to the left ground at the RCA jacks.  This eliminates a source of noise.

 

[Doc B]

Are you getting the same voltage at the outlet with or without the Tripplite in there? I'm thinking you are, but thought I'd better make sure. I'm kinda with PJ that this could be an issue of low voltage at the outlet creating a regulator issue in the BeePre. Can you get the voltage to come up at all if you turn off everything except the amp and preamp? That drop from 118 to 115 or 114 seems pretty big for just a couple pieces of audio gear. I wonder if there is a connection in the house wiring that is less than perfect and creating some resistance. The fact that the outside lights are on the same circuit as wall outlets is, well, it's as bad as my house! We have a furnace, washing machine, microwave and some lights on one circuit. Completely stupid, and you would think I would do something about it besides go downstairs, turn off the washer and reset the breaker every time somebody turns on the microwave the when the washer and the furnace are running.

 

[Grainger49]

If you have less than positive contact in your light and outlet circuit you should get an electrician (licensed and insured) to come in and make all the terminations over.  The terminations at the outlets should be on the screws not the pins inserted from the rear of the outlets.

Dan, any molded case breaker that has tripped 6 times is no longer tripping at the name plate value.  It should be replaced.  They work on a bi-metalic strip that anneals and changes its value after a half dozen trips.

 

[Doc B]

Thanks Grainger, I should indeed replace it and reroute some of the cap appliances on the circuit.

 

[Paul Birkeland]

I concur that some inspection is in order.

I thought I was being all Mr. Handyman when I put a new microwave/range hood in, but the circuit feeding it also does my bathroom lights.

On the plus side, I know when my coffee is finished being reheated while I'm in the shower.

-PB

 

[Grainger49]

I'd never give you advice on house wiring but the circuit breaker advice came from my buddy Ron.  He has worked for Square D, Cutler-Hammer and ITE/Siemens in the molded case breaker divisions.  I've replaced several since receiving that advice.

 

[4krow]

Eight years ago, I bought my house that was constructed in 1930. To cut to the chase, EVERYTHING from the power transformer to the circuit box, and even a dedicated line was replaced, not to mention every outlet in the house. Even after all that, I found the best relief from first buying a large isolation transformer with 8 separate secondary windings and using a PS Audio P500 on one of those windings to do the rest. Almost everywhere I have lived has had to one degree or another, voltage/noise problems. You have to start somewhere, and more often than not, I find loose connections and more in one or more electrical outlets. You might start with this thinking and work your way back.

 

[johnsonad]

A similar experience. I'm active duty Navy and move every three or so years. The best piece of gear I own is a PS Audio Premier Power Plant. Constant dependable 120v output no matter where I've lived including Japan!  Having clean power makes a large sonic improvement.

 

[Grainger49]

I'm running all my analog pieces on an old, first product, PS Audio P300.  It is fed from my wall outlet.

 

[aroide]

I had serious noise issues with my BeePre.  After sleuthing, I realized that my AC voltage at that plug got down to 116V at times.  At the breaker box, 120V, but lots of loss through all the wire nut connections and distance with a large current draw device (plasma TV) on the circuit.  I did buy some silver conduction 'grease' but never got around to putting it on all the connections on that circuit.

In the end, I threw $$ at the problem and bought a PS Audio regenerator to get Ultra clear 120V and my BeePre has been very happy ever since.

Its a bit scary that houses can have so much resistive loss in the wiring.

 

[crgolfer]

I also had noise problems related to my plasma tv.  I couldn't find the cause until I noticed that the noise went away when switching channels.  The noise did not start until the tv is on for some time so there must be some kind of noise buildup going on.  I switched the wall connections around which seems to have solved the problem.

 

[aroide]

My voltage is low (as low as 112V) in my listening room also as its on the same circuit as the family room plasma tv and has the longest wire runs in the house.  The Bee Pre does not like lower voltage I have found.  Re-wiring house circuits is expensive, so my about-as-expensive-but -better option was to buy a PSAudio power regenerator.  Now I have ultra-clean, fairly low impedance 120V and very happy audio gear.

 

[elko]

I'm living in the Netherlands, and my Beepre struggles with the power (230v), the wallsockets deliver, to. When the voltage drops i'm getting some terible hum in my left channel. I already tried a small powerconditioner from furman. This device only filterd incoming power from hf noise. This didn't helped that much, so i send it back. I'm reading on this topic about the AC regenerators doing a marvelous job. Unfortunately such a device is way out of my reach pricewise. Nearly €5000,- is a really big investment.

Maybe i found a budget solution. What if one uses a DC-AC converter, the devices uses in caravans and motorhomes to connect home equipment to a 12v or 24v DC source. There are ones availble producing pure sine wave output at 230V. Connect one to a 12v DC supply so no batteries are needed.

I already orderd one of these devices and going to try this out soon. What are your thoughts on this. Is it actually a good idea or can i harm my equipment?

 

[2wo]

If your line voltage varys that much. How about using a Varic to supply it?  They are not that expensive and you can dial in the voltage of the day...John