Conrad Johnson Owners.com

I was wondering what people were using for the power condition (if any) in their systems. There are so many options that go from inexpensive to astronomic prices. There is also wide opinion on how much of difference these make in the actual quality of sound.

I figure I share what I am using as it has been a good product that did not cost a lot of money and my dealing with APC's tech support was outstanding. If your looking for a good but inexpensive solution, this may be of interest to you.

APC H15BLK AV 1.5kVA H Type Power Conditioner

I have to admit that I never really had a major problem with line noise or interference so I bought a power conditioner more for protecting my equipment fro major voltage spikes and general fluctuations in voltage when my home's appliances turn on and off and fluctuate the line power (refrigerators, boilers, water pumps, etc..).

This APC unit does a good job at keeping the voltage at a steady 120 V +/- 2 V. The construction seems rather sturdy and has 12 standard plugs so if you want to plug "everything" in at the same time you should not have a problem. It also offers delayed activation for the individual plug so if you have a big amp that will draw a lot of power on the startup it will not effect the other electronics which is kind of nice. There are other filter connectors as well for coaxial cable and telephone lines (which admittedly I do not use), but are nice to have on there and often not included in much more expensive power conditioners.

When I had bought the first unit it did develop an issue a few months in and I called tech support up. They immediately sent out a new replacement unit and just told me to send the broken one back in the same box. I thought that this was pretty incredible service for such an inexpensive unit. I have been using the replacement unit for 2 years now without any new problems. I also spoke with an American tech support person, not some cheap call center in India. Even the best electronics can fail and having good tech support is a big plus in my opinion.

Here is the product website link for the unit.

If you are looking for good and inexpensive power conditioner I would suggest you look at this unit prior to spending big money on other products.

I noticed an ever so slight buzz in my power conditioner when my ART Amps are on. I took the cover off and it seems to be coming from the right side of the unit where there are small coils and relays. I think these are supposed to be filters. I tried manually pushing on the components while the power was on (with a non-conductive tool) but it did not change the sound. The volume of the hum is very low but I can sometimes barely appreciate it at listening position between songs so it just bothers me to know that it's there. Audio quality of the system is not effected.

I'll have to do some experimentation but I may just try putting vinyl acoustic insulation into the right side of the unit and see if I can lower the sound by a few db.

Hey Admin,

Just came across your post. I had a very similar hum using a PC back when I just acquired the monoblocks driving the ML Ethos. The PC I used at the time wasn't anything high-end but it had some fancy features; voltage correction, brown-out sensors, high voltage cut-outs, filters and all sorts of other gadgets, including calibration to measure incoming voltage and correcting it by +/- 3% or 5% settings leading onto the output voltage. It had a massive tranny and could handle a big load, so the manual says... The brand was a Thor PS-10. It worked ok, as intended, with a single stereo amplifier on but the moment I plugged in the monoblocks, it started humming. I also tried the larger version of the Thor PS-20 but resulted in the same hum.

The initial and continuing draw current from the monoblocks was too large a load for this unit, hence it also crippled the true dynamics and frequency extensions the system was capable of. In the end, I just unplugged it and never used a PC from there onwards. Going direct to the AC mains, plus a dedicated AC line on a high-grade CB worked wonders! The results were far better than any PC that I tried subsequently just for peace of mind.

Obviously those ratings/specs stated by Thor were not quite accurate, and later I was told by the rep/dealer that their PC appliances are not meant for real high-end gear, rather low-end to mid-fi gear... go figure!

Now, this doesn't mean that your system rig is too heavy a load for your particular PC that you're using but I would think that those ARTs are not for the faint-hearted. These things really need to go straight into the wall with dedicated AC lines. It helps the amplifiers and the system overall, even though we may not feel the immediate results. I would investigate further as to why this hum is occurring and wasn't an issue before. Try the ARTs just without the PC and see what happens for a few hours.

interesting to know the outcome, keep us posted.
Cheers, RJ

The first PLC I recall specifically designed for audio was VPI’s, back in the 80’s.

It was reconstructing your AC voltage wave form and frequency. It was a low power unit intended to clean up noise for turntables or other low draw motors.

It was very prone to buzz/hum.

Any time you are reforming a wave, it is important to consider internal isolation, and I suspect that capacitor choices and their aging have a significant impact on this.

PLCs have their place … but it’s not here in my system.

I've tried using a typical power strip with the system and I couldn't hear a significant difference in the music quality. I really do like this unit for a couple of reasons however.

1) It is convenient to be able to cut the power to all equipment with one button and to completely disconnect all units at once during lightening storms.

2) We have voltages fluctuating in the area I live and I can see the unit correcting for it quite often. I rather feed my equipment voltage as close to 120 as possible.

3) I case of a power surge while I am listening, it should provide an extra layer of protection via it's built in circuit breaker. We live in a forest area so much of the powerlines go under or through trees in my town. It is not uncommon to have the power go out so I am always worried that this may happen while the stereo is on. I pretty much don't have the system on if there is a storm or high winds.

I may have to experiment a little more. I do have some dampening material coming in the mail later this week so I am interested in seeing how much it will dampen the buzz once I have it applied. If I don't like the results I may have to go with another or more direct solution.

A positive side effect of plugging everything into one PLC is that this approach automatically eliminates the possibility of ground loop issues that originate in the room’s wiring.

I have had a lot of ground loop problems in my setup in the past. That's why every time somebody on here posts about any noise or hum, the first thing I chime in with is "must be a ground loop".

All power has to flow from one receptacle, otherwise I have noise. It's one of the reasons I got the unit in the first place. I have 3 separate lines going into my home theater room. One I use exclusively for my stereo setup, one for my home theater equipment, and the last for lighting.

As I think back on the VPI PLC, I think a major goal was to have frequency adjustability in order to control platter speed, though other benefits were touted.

I think a problem with the VPI unit was lack of smoothing. It was really making square waves if I remember right. A square wave has all sorts of higher order frequency components when resolved to its Fourier series. No wonder it buzzed.

Ah! Yes, I remember you mentioning voltage issues in your area Admin. In which case might as well be safe than sorry.
Even though insurance companies may cover whatever natural disasters and power failures occur, when it happens it's still a bumper, waiting for things to get fixed and most of all, no fine tunes... definitely not a good feeling.

Hope you manage to get that hum sorted out soon. Let us know how it goes and what was causing it. Always a learning curve.

Cheers, RJ

Hola Chicos,

My recommendation is to use a big toroidal transformer with a capacity of at least 20A of current. The balanced AC line is the way to go, at least here in Costa Rica, for cleaning up all the AC power source. What the transformer does is to convert the 120V hot line into two 60V hot lines and a common center. This way, all the dirt stays in the first primary wound and the result is a clear stable AC.

My power conditioner brand I think is out of business. It is a BPT (Balanced Power Transformer) BP-3.5 Signature Plus. Here is a review of it: https://6moons.com/audioreviews/bpt4/plus.html

Furman has it too. I do know that PS Audio has a good one too. There is only one here in CR and the customer is very happy too...but I am with the old technology for this purpose. Balanced line increase the impedance and due to the fact that both lines are hot, have opposite phase and then they cancel any possible noise.

Happy listening!

Hola Admin,

Regarding the odd noise coming from the Conditioner, you should disconnect one power amp and see what happens. If the noise is gone, then, disconnect the remain mono block, and reconnect the first one. Have a listen. If there is no noise, two mono blocks are too much for the Conditioner.

My guess, with much respect, is that your power conditioner has no juice to carry such big monsters together...

Happy listening!

Too much power draw certainly may the cause. I hope it isn't because I really like the function of the unit. I was listening the other day with the cover off and I didn't hear it from listening position but I'm sure it is still there. I also put the amp connectors into different plug slots and that may have helped a little, but questionable. I got some acoustic isolation material in the mail yesterday so I will apply some to the case interior to see if that works in suppressing the sound to the point where I can't hear it. I'll report back on the progress.

Admin,

Be careful, you might be overdriven the conditioner. I understand your love for it, because it is a fine conditioner...but you need a bigger for those big amps...if you a hearing a vibration, this means that you are overdriven the banks dedicated for the power amps. I am sorry for the bad news...you could burn the unit.

Happy listening!

https://www.ebay.com/itm/122017841898?_ ... %3A2334524

These are new, you might find used for the half price and these units are difficult to brake.
Happy listening!

https://www.ebay.ca/itm/265144745988?ha ... Swrgpgjdwc

This unit is in Canada...the current capability is 30 Amps. This unit will drive all your system or mine easily.

Happy listening!

Maybe a new power management unit will be needed indeed. I hate to get rid of the APC as it served so well thus far but if the ART amps are truly too much for them to handle I probably will have no choice... I did just install the dampening material into the unit so I want to put a few hours of listening on it again and see how I feel about it.

An alternative is that I may buy a outlet extension specifically for the amps and then just keep all the other equipment on the APC unit. Maybe something like: http://signalcable.com/magicextension.html

The most important thing is I want a manual switch to separate the equipment from the power line in case we have a lightening storm or severe voltage fluctuation that could damage something more sensitive down the line.

Admin,
Dampening material will not cure the problem, it will cure the noise. The APC is overpowered with the load of the two monsters . It is a good idea to separate the amps and keep the APC with all other goods. Very clever idea!.

I am sure that your system will sing much better once you have provide the right energy for both amps. Just for a try, unplug only one power amp, and you will find that the APC is capable to drive only one power amp, not both at the same time. This also tells me that it is much better to power the amplifiers with separated conditioner that can handle the amps energy consumption. I think I am ahead of what's going on...the problem is that I had that noise before with my Transparent power conditioner, and I never thought that one of the transformers were going to fail. So, heavy vibration is not a good thing in the power conditioner...this is the reason why I am alarming you about it. It is a frightening thing.

Happy listening!

I will try to do some experimentation this weekend to take the amps off the APC. Interestingly, we have a hurricane coming later this weekend and these are the reasons I like to have a complete disconnect from the main lines.

Admin, please protect your self with the bad weather. We don't get too many hurricane here in Costa Rica, and the ones that have, made a lot of damage.

Have fun doing the tests!...and I hope you, family and friends to be safe with the hurricane.

Happy listening!