Power conditioning as audio tweak

That's interesting Tony, I have not tried the power plant yet. I'm lucky in that my power appears to be pretty clean - dedicated lines/upgraded power cords were the only things that made a significant improvement.

 

The downsides for me for my PS300 were high heat, low power output, and the thought of all that electricity I was wasting to create power for my components. I find that the BPT does 99% of what the PS unit did, without those drawbacks.

John K.

 

You make a good point about the power signal shape. Remember everyone, any device which creates voltage gain (almost all audio components) simply modulate the line current. That is how they work. AC current (in the US) ideally a perfect sine wave with an amplitude of 120 volts. That wave moves into the power supply of an audio component (say an amplifier) where the negative half's of the waveform are cut away. The voltage is now DC since it is all positive, and is no longer alternating. That voltage is then sent to capacitors where it is smoothed out a bit (low-pass filter), and stored. When you pass this current through the output devices (tube or transistor) and pass an audio signal through them at the same time, the audio signal will modulate that current, pushing it positive and negative. The more audio signal you put into the output devices, the more current is needed to accurately mimic the input signal, therefore drawing more current from the power supply. At a certain point, the power supply will no longer be able to keep up with the audio signal. When this happens, clipping occurs because there is literally not enough current to accurately mimic the amplitude of the incoming audio signal. The power output of an amplifier is determined by its power supply.

What I am getting at is, if the line signal is not pure, neither is your audio signal.

<end rant >

 

John, I have never had a heat problem from my PS300 (maybe it is hotter out there in those western hills) and while I have no idea what the efficiency of the PS300 is, using it only for my front-end it seldom produces more than 100 watts which even if it needs 200W or 300W to produce is nothing compared to running my AC in the summer.

 

To clarify, by heat I mean that the 300 got so hot it affected performance--my front end components at the time used around 150 watts, and even at this level the P300 would often shut down in the summer in my un-A/C'd listening room. I bought one of the very first P300s, which didn't come with a fan; PS Audio noted heat-caused problems and so the later ones came with a fan, while an upgrade was offered for earlier P300s. In my listening room, and at lower listening levels the noise from the upgrade fan was noticeable and objectionable to me. By power wastage, I mean that to produce 200 wats, the P300 uses, what, something like 350-400; that doesn't seem like a good ratio to me as I pay my own electrical bills. The BPT has no heat problems, is something like 98% efficient, and allows me even to plug my amplifier in (if I'm not listening at crazy-high-power-current-demand levels). I liked a lot of what the P300, but it doesn't fill my current needs.

John K.

 

Balanced AC power is the way to go, and Equitech is the pioneer of balanced power systems.

From www.equitech.com -


What is balanced power?

When 120-volt AC power is balanced, one side of the circuit has +60 Volts to ground while the other has -60 Volts to ground. A European 230 Volt balanced power system has +115 Volts and -115 Volts to ground on the conductors.

Standard unbalanced AC power systems have a "hot" conductor and a "neutral" conductor. In the US, the "hot" conductor nominally has 120 Volts to ground and the "neutral" conductor has 0 Volts to ground. Europe has a similar system but with 230 volts on the "hot" and 0 Volts on the "neutral."

In a balanced power system, the voltages on the system's two output terminals are 180 degrees out of phase to each other with respect to ground. The system reference (ground) originates at the output center tap of an AC isolation transformer. In other words, the system's grounding reference (zero position) is located at the system's mean voltage differential or zero crossing point of the AC sinewave. This is a far more effective way to establish a reference potential for an AC system. The center tap is then grounded to Earth for electrical safety and for referencing shields.

There is never any voltage or current present on the ground reference in a balanced power system. Transient voltages and reactive currents which normally would appear on the neutral and ground wires are also out of phase and likewise, sum to zero at the ground reference thereby canceling out AC hum and noise.

A balanced AC Power system works the same way as a balanced audio circuit but with a higher amplitude. Both balanced audio and balanced AC incorporate phase cancellation or common mode rejection to eliminate noise.

Why do I need balanced power?

Power standards for electrical distribution were adopted many decades ago and haven't changed significantly since. With the advent of sensitive electronic applications, electrically induced interference has become a matter of concern to engineers. When electrical interference is present in any sensitive electronics, equipment performance will be limited by the noise. The problem is critical in many areas of high-tech electronic engineering, among them, the sound recording and video industries. A very low noise level is crucial in these areas because literaly, the noise can be seen and heard.

The dynamic range of the entire electronic signal chain determines the quality of the final product in all recording environments. The presence of any electrical interference at all lowers the S/N ratio of the recording. This limits the subtle detail and realism of the sound or image. Low level signals are lost in the noise floor of the system.

Sound quality can also be affected by intermodulation distortion occurring as a result of the presence of ac noise in the audio or digital signal bandwidth. Even if the noise level is inaudible, it is likely that program material will be colored by the presence of electrical interference.

In more sophisticated areas of application, for example high-end digital signal processing (such as broadcast automation or even MDM recording), unacceptable error rates are often attributed to background electrical interference. Digital jitter is the "smoking gun" that points to high frequency AC noise. Digital jitter is caused in part by high frequency electrical interference approximating the bit stream rate of the digital signal.

Balanced power eliminates all of these problems because there is never ac interference present on the ground to invade signal circuits. Balanced power often increases the dynamic range of a recording system by 16db or more. When balanced power is applied, ground loops and hum problems, even subtle ac noise coloration becomes a thing of the past. The difference can be astonishing.

 

John, So sorry to hear about your problems with the early P300. I have a later generation one. The only time I hear the fan is when I am right on top of the thing. A 50% efficiency is not unusual for a power amplifier, which is what the Power Plants are.

 

So then, what's the best balanced power product out there: the BPT series, Z-Cable's modified BPT Supreme series, Equitech, or as I just found out by reading this thread, the Furman IT 1220/1230? My concern continues to be the effects of any of these on my equipment and the music. These are expensive experiments and I am not sure that those that are espousing external whole house protection, dedicated lines, and upgraded wall outlets instead are not right on! In a perfect world where money is not a factor the answer might be ALL OF THE ABOVE, INCLUDING A CONDITIONER.

 

Well Tony, you sold me. And PS Audio's website did too. I really do need to hear this for myself.

My P300 arrived on my doorstep today. I'll be giving it a test run this weekend .

 

Greg, We all expect a full report this Monday. Another great thing about PS Audio is they are very helpful over the phone, if you ever have a question just call them.

 

Oh Greg, where's the review???

 

I have had very good luck with both Richard Marsh designed Monster power conditioners and Cardas power cables. Both lowered my noise floor noticeably.

I also have some experience with Shunyata and PS Audio and can recommend both.

 

I sould add one thing...depending on conditioner it may make sense to plus the amp directly into the wall unit and bypass the conditioner altogether. That is the case with my HTS-5000.

 

My 2 Cents On The PS Audio Power Plant

It's really hard to write a review when all you want to do is sit and just listen to music. And I do mean JUST the music, NOT the system. That's what has happened with me since plugging in my pre-amp and CD player into the PS Audio P300 Power Plant.

I guess I should say right up front that I didn't expect a lot from a power conditioner. No more than say changing out an IC or speaker cables. Yes, you can hear differences in a system in doing these things but in my experiences the changes are subtle at first and then they may or may not start to grow on you. This power conditioner took my system and I by storm!

I decided to not run my amp through it because I'm afraid it may be too much of a power hog. Have not hooked up the VPI to it either because I wanted to play with the settings and you cannot do this while the table is getting it's juice from the Power Plant. I will try this later, after I'm over the newness of the multiwave mode while playing vinyl.

In listening to my system now, I hear a much more refined sound. Things just sound right. Like on one of those days when you feel like your system is running on all it's horses? That's what I hear. Smoother top end and mid-range, increased dynamics and a lower noise floor. The Power Plant has especially had a big impact on the bass response. My Cornwalls are loving it. I hope the neighbors do too. Using the multiwave function I do like what it does for some recordings, older ones in particular, but for the most part I just keep it in neutral (60Hz-117v) and let her rip.

In my mind this tweak really is as advertised. Heck, I'm already thinking about upgrading to the Multiwave II Plus.

Tony, thanks for the introduction. I'm really enjoying it.

Now that's 6 weeks of eating "wish sandwiches" until I get my finances back in order .

 

Greg, Glad you like it.

 

Also the case with my Seventy. My system had been bugging me for a while and when I unplugged it from my Inyoue': Synergistic power/line conditioner and plugged it into the unswithched 500MA socket on the power supply of my DR-6 pre amp. the difference was immediately noticed and appreciated. The top end and upper mid range seemed to both open up and smooth out by just taking the sharp edge off, but revealing more.