Turning hobbies into products

Picking up on our story of the isolation base shootout at the Munich High-End show of a few years ago,we move back to Boulder Colorado and jump ahead a few years.

In our main listening room everything was powered by a Power Plant Premier sitting on the aforementioned wooden isolation base. I had tried to remove it on several occasions because of space restrictions but every time I did the sound was noticeable deflated and smeared or muddled sounding. Sigh.

At the time we were working hard on designing the new PerfectWave series of Power Plants and moving production from China to Boulder – an undertaking of massive proportions for us and one I would never want to repeat. Working with our mechanical engineer Bill Abplanalp, I wanted to make sure the new Power Plant design took care to address some of the issues I suspected were to blame for the Premier’s sensitivity to microphonics and vibrations. To be honest I was hoping to eliminate the need for the wooden base.

Bill came up with a number of clever additions, using heavier materials, soft density polyurethane mats under the big transformers and a unique heat sink design that would diffuse some of the vibration transmissions picked up by the “singing” heat sink fins and transmitted back into the amplifier components.

Bill’s work was well received and the new designs much less sensitive to being on or off the base but still, I could not live with the new P5 or P10 off the base. That bugged me for the longest time and I began to get the itch to try and solve the problem. At first the new isolation base idea I worked on was just a passing hobby but later it got more interesting and began to form as a real project that used engineering resources.

Understanding that I needed a combination of mass and diffused contact with the resonating surface the base would sit on, I started out with a huge 1/4″ thick plate of raw steel that weighed about 15 pounds or so. I mounted a set of rubber feet below the plate and set the Premier on top of it. Interesting results. There was a definite improvement but not as good as the wooden base.

Tomorrow the new base takes shape.

Paul McGowan – PS Audio, Intl.

The beginning

The beginning

Reader David Zigas sent me this quote after reading yesterday’s post titled 1+1=3. ”As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality” Albert Einstein.

Thanks David, you gotta love Einstein quotes.

What I was referring to was our new product concept piece called the PowerBase – which is a new idea that combines two essential elements together – an isolation base and a power conditioner to build a unique product whose sum is greater than its parts taken separately.

Over the last week or so we’ve given you a better understanding of what and why power and microphonics matter in our high-end systems and today I will start to share with you the process of how we got to this idea of the PowerBase and then we’ll wrap up the discussion and move onto a new subject.

Most inventions happen out of necessity and the PowerBase is no different. While at the Munich high-end show a few years ago I ran into a fellow who was building an isolation base for equipment and he was very excited about what he had built. Formed from multiple density pieces of wood in a unique pattern that he had designed over a few years of experimentation, this heavy wooden base was touted as “blowing away any cones or feet”.

We’ve all been to the “mine blows away yours” party but being the polite fellow I am I heard his pitch and agreed to a shootout that very evening in our booth after the show closed. Come the evening it seems I had forgotten he was coming by – all that was on my mind was a cold Hefeweizen beer of which the city of Munich is famous for. Not much can deter me from a cold German beer in the evening after standing on my feet all day but in he walks, isolation base in hand, and ready for battle.

As this was a few years ago all we really had to display at the show was our Power Plant product – the PerfectWave DAC still in engineering – and he was anxious to show me how much of an improvement it would bring. The Power Plant Premier was on machined metal cones more for looks than anything else as I had previously auditioned it both ways and didn’t hear a significant difference between on and off cones. But hey, it’s a show and we’re there to impress.

Once we listened to a good orchestral piece we were all familiar with we left everything exactly the way it was, lifted the Premier off the cones while he slid his base underneath and down came the Premier ready to go. We played the same piece again at the identical level and jaws dropped – most notably mine. We repeated the test multiple times and I was simply stunned and mystified. This was a Power Plant not a preamp, amp or DAC. It produces a pure sine wave from the wall and should be immune to what it sits on.

Over beers that evening (finally) we talked about his theory of why it worked, which boiled down to diffusing the vibrations with both mass and different density materials and – unlike hard metal cones which had the same density and little to no mass – the platform “just worked” and I had to admit he was right. I bought several from him and have used them ever since to great advantage.

The story continues tomorrow.

Paul McGowan – PS Audio, Intl.

1+1=3

1+1=3

We’ve covered some good ground in the last few days: power and why it matters, vibrations and microphonics and why they matter. I have also ruffled a few feathers on these topics and that’s ok – I am sure it won’t be the first or the last.

Where we’re headed in the series is as promised: to understand the process we went through designing a new concept piece for high-end audio.

Most new product concepts are borne out of combining several existing products into something new: a wagon plus a motor and you have an automobile. A battery, wire, relay and switch and you have the telegraph. A woofer and a power amplifier combined in one box and you have a powered subwoofer. A power conditioner and an isolation base combined together and you have our new product the PowerBase.

Now certainly I am not suggesting that the PowerBase is on par with the invention of the automobile, the telegraph or the powered subwoofer – it is not. But in the same way each of the examples I gave solved a problem or filled a need, so too does the PowerBase.

By combining the isolation needs of every audio component (both electrical and mechanical) into one product, the result is what any successful new concept hopes to achieve – that the sum of its part is greater than the whole.

Tomorrow we’ll look at how the concept came to life in detail and what it means.
email 1+1=3

Paul McGowan – PS Audio, Intl.

Counterintuitive

Yesterday we discussed that cones and spikes under electronics is probably not the best idea if you want to really address the problem of smearing caused by microphonics. Yes they work and yes your equipment will sound much better with them in place, but they do not really solve the issue they were intended to fix – they only reduce it and can cause other problems at the same time. I think this statement got the hair on the backs of some readers necks up so let me be clear. In general, cones and spikes DO help a lot. I just don’t think they are the best way to go. Read on.

Today I am going to propose we actually stop trying to reduce vibrations and increase them instead. Yup, counterintuitive for sure but stay with me and I’ll explain.

Hard coupling your electronics to surfaces has only minimal benefits of vibration reduction when what we really want to do is find a way to diffuse and mask the ghost imaging problems in our electronics instead. If you can diffuse the vibrations and actually allow the diffused energy to couple to the equipment then what you wind up doing is adding a form of dither to the signal.

Dither is a form of noise usually associated with digital electronics. It is added to data streams to randomize fixed inadequacies in the conversion process of analog to digital. But if we take advantage of dither for our vibration reduction techniques we can make serious headway in both surface-borne and airborne vibrations.

It’s important to remember that while we may be able to reduce surface-borne conducted vibration energy from our equipment it’s nearly impossible to reduce or eliminate the airborne vibrations in our listening rooms. With sound pressure levels of 100dB or more at the equipment this is not a small issue and the easiest way to effectively manage these is to hide or mask them since we cannot eliminate them.

So here’s what we do. Instead of minimizing the surface contact area of our equipment we actually increase it so we get effective surface coupling. Next we diffuse the coupled energy with a series of tuned broadband conductors so that the end result is a dithered (randomized) vibration energy we WANT added to our signal. If we add our dithered energy to the signal the ear/brain will ignore both the airborne and surface-borne vibrations because they will be interpreted as random noise.

So the secret to eliminating the smearing problem all our electronics suffer from is not through futile attempts at eliminating the problem – but rather by masking it.

As they say, if you can’t beat them, trick them instead!

Tomorrow I’ll start tying the power and the vibration lessons we’ve been going though into a new product concept that I’ve been promising I’d walk you through.

Paul McGowan – PS Audio, Intl.

Diffused vibrations

We’re in the middle of our mini series on power and vibration control for our hi fi systems. Yesterday I explained that vibrations, caused by the loudspeakers in our listening rooms, were inevitable and instead of focusing on minimizing or eliminating them we would be better served to treat them like we would room reflections.

When you play speakers in the room you get reflections off the room walls. You can try and absorb and minimize those reflections or you can scatter and diffuse them instead. Over the years we’ve learned that diffusing them is a much more effective tack than absorbing and this is because when the reflections are diffused, our ear/brain mechanism will interpret them as random unrelated noise and easily ignore their contributions.

If we use the same technique on vibration and microphonic control we get the same results – that of the ear/brain ignoring their contributions. Diffusing is far better than reducing and here’s why.

If you try and damp out the vibrations occurring in your room you will be only partially successful – because you simply cannot eliminate them all. Whatever is left is still a focused and related ghost image riding on your music and, although reduced, it will still be perceived as distortion and smearing in your listening environment.

Cones and spikes under equipment, for example, reduce microphonic effects but don’t diffuse it – in fact they probably make it worse and here’s why. Cones and spikes work by reducing the contact area between the equipment and the vibrating surfaces. They are, by their very nature, extremely rigid and transmit specific frequencies to the equipment – thus further focusing the unwanted energy. Several manufacturers have used varying hardness materials within a cone to help this issue, but in the end their purpose is to reduce contact area and thus reduce surface-borne vibrations. The second problem they have is that they do not address airborne vibrations.

In fact, at least half of the microphonics issue comes from the airborne vibrations and, unless your equipment is in an acoustically shielded environment, there’s little any of these isolation bases and cones and feet can do to help. They are valuable under the speakers but I would recommend not using them under the electronics.

So the best answer is, again, diffusion and masking rather than absorption, isolation and futile attempts at vibration reduction.

Tomorrow I’ll show you how this works.

Paul McGowan – PS Audio, Intl.

Tesla puts it together

Now we’re getting to the core of understanding how power in our hi-fi system is transferred from the wall and in the next few posts we’ll start to understand how we convert this power into music. First let’s wrap up our little history lesson on why we use AC power at all.

If you’ll remember, Tesla was getting ready to change the world from DC to a new form of DC called AC, something we use in our homes to power our stereo systems to this day.

Nikola Tesla was poised to build his AC power system based on the idea that each home or block of homes would connect to a very high voltage AC main line through a transformer – the transformer reducing the high voltage to a lower and more usable voltage for the home.

As we’ll remember, transformers only work when the power that feeds them is moving between plus and minus rapidly – something we call Alternating Current or AC. But Tesla had a problem and in a matter of only a few days he solved that problem and created the modern power grid still in use today.

The problem he had was generating the AC and once generated using it directly to make a motor work. In those days, dynamos or generators as well as motors were all generating and running off of DC. The dynamos that generated the DC and the motors than ran from DC were essentially the same things – each used in reverse of the other. This was sort of the same thing we’ve seen before with coils and magnets – if you spin a motor it makes electricity and if you put electricity into a motor it spins.

It was known even by Michael Faraday a decade earlier how to generate AC – one simply used a physical magnet connected to a hand crank in close proximity to a coil of wire. When you spun the magnet (a long straight bar of metal turning end to end) it would change the magnetic field from plus to minus and what came out of the coil was AC. But no one knew how to make a practical design for that and, perhaps more importantly, no one knew how to use that AC to make a motor.

Over the course of only a few weeks, Tesla saw the entire system in his head and in one of the great strokes of genius figured out the modern power grid, invented the AC motor, the AC dynamo, the efficient AC power transformer, and the system that would make it all work. Tesla’s grasp on the fundamentals of coils, electricity, magnetism and the efficient means to use all those elements together is unmatched since the genius of Michael Faraday who set all this in motion.

Within but a few years time, Westinghouse and Tesla’s new power system took over the modern world and sent Edison home to work on other projects like the phonograph, the motion picture camera and the thousands of innovative products he invented or brought into the world – but power was not to be his fame – it was Tesla who would make the leap necessary to build the world’s power grid – still in use today with but few changes.

Edison never gave up the fight for DC, even inventing the electric chair to prove just how dangerous AC power was. Edison personally electrocuted hundreds of animals and more than his fair share of condemned prisoners in public showings around the country – all in an effort to prove to the world AC was not to be used. But in the end AC survived even to this day.

Here’s a picture of Edison personally strapping in the first victim of the electric chair he invented to prove how bad AC was.

Paul McGowan – P Audio, Intl.

So, now you understand why AC is what comes into our homes and why.

Paul McGowan – PS Audio, Intl.

Fighting the good fight

I remember years ago when one of our more obsessive customers drove a 100 miles to visit us in hopes of offering some enlightenment to Stan and I. The claim was that this person had discovered a new product idea that made a world of difference and wanted to both share it with us and get our advice on how to market it – so excited was he about this discovery.

We were both curious as to what marvel was being shown to us when out of a well sealed box was drawn, with some fanfare, a large and solid stone brick with a pad of rubber on the bottom. ”Your discovery is a brick?” He insisted we listen to his brick placed on and off our preamplifier – and indeed when the brick was on the preamp the sound was noticeably improved – off it was worse.

“This isn’t just any brick. After a lot of tests I have figured this particular type of stone is the best. I intend to have it polished and packaged properly and wonder how much you think I could sell this for?”

We tried hard to explain to this well meaning fellow that what he had discovered was a way to damp the chassis of the preamp and lower vibrations caused by the loudspeakers in the room. The quality of the brick was all about how dead and heavy it was relative to another type of stone and charging a lot for a polished brick was, well …… But trying to convince him there was no magic to be had was a tough chore.

As Audiophiles we go to great lengths to help wring out the most from our systems and doing what we can to reduce microphonics through lowering vibrations to the equipment is a worthwhile endeavor if it is done in a way that makes sense. Everything in our system is somewhat microphonic from wires to PC boards but some makes more of a difference than others.

Decoupling the source of the vibrations, the speakers, from the room is a great place to start. I have seen every scheme from hanging the speakers with ropes from the ceiling to simple spikes that reduce the area of contact to a minimum. And while it’s a good idea to do what you can, I don’t personally think it’s worth a whole lot of effort because at the end of the day the majority of problems with microphonics occurs through the air.

One of the most effective vibration/microphonic reduction techniques you can use is lowering the impact on source equipment and anything that has a vulnerable signal that starts out small and gets amplified from there – because the amount of added ghost signal from the speakers increases by the amount of amplification.

Let’s jump into that tomorrow.

Paul McGowan – PS Audio, Intl

Ghostbusters

We’ve been focusing on microphonics and how they affect the performance of our AV equipment. Vibrations from the output of the loudspeakers in our room generate airborne as well as floor-borne movement that is coupled into the audio signal we listen to forming a type of insidious loop that smears the music we listen to by injecting a type of “ghost image” onto the pure music.

This ghost image is a distorted and time delayed copy of what’s coming out of our systems. The sharper the focus or imprint of this image the more noticeable it is – so we work hard to decouple our equipment from these vibrations by putting spikes under our loudspeakers, installing heavy shelving to set our equipment on etc.

The problem is that unless you put your kit in one room and the speakers in another you’re going to have to deal with this problem as it will impact your system and its performance.

I like to imagine this problem like I imagine the issue we wrote about earlier, the actual room itself. We know that our listening rooms contribute mightily to the sound we hear and mostly not for the better. The same type of delayed and distorted image of the sound hits our ears after it bounces off the walls of the listening environment. Again, the sharper the “focus” of the reflected sound the greater the problem we hear. This is why diffusing the sound with wall mounted diffuser panels works.

Because we cannot eliminate the walls in our listening room we have to deal with the reflected sound – and the best way to do that is diffusion. Diffusion works because it defocusses the sound into something the brain interprets more as noise to be ignored rather than interfering with the image. If you can’t eliminate something at least make it less noticeable – and that’s what we need to do with our microphonic issue.

Realizing that we cannot eliminate floor-borne and airborne vibrations within the listening room we need to stop trying to eliminate the effects of the vibrations and figure out how, instead, we can diffuse them properly. That’s the key we’ll discuss tomorrow.

Diffuse the vibrations and bust the ghosts.

Paul McGowan – PS Audio, Intl.

Singing stereos

We started our discussion yesterday on microphonics and how everything in our hi-fi systems can act like a microphone picking up sound in the room and adding it to the music.

So why is this undesirable? Imagine for a moment an extreme version of microphonics. Mentally place a microphone in your listening room, perhaps 15 feet away from your loudspeakers and next to your electronics. Take the output of the microphone and mix it into what you’re feeding the power amp driving your loudspeakers. What you get is a time delayed ghost image riding on top of your clean and perfect music.

The time delay happens because of the distance the sound travels before reaching the microphone. The ghost image that is added to the pure music signal is a pale and out of synch version of the real deal. This is real distortion that can make what we cleaned up with a better power supply look pale in comparison.

None the less, this is exactly what’s happening in your equipment unless it is in another room because your equipment is chock full of little microphones: capacitors, PC boards, tubes etc.. I suspect most of us are stuck with our hi-fi systems in the same room as our loudspeakers so this is a real problem and one we need to figure out how to minimize.

Tomorrow let’s look at some of the ways people minimize microphonics. You may be surprised.

Paul McGowan – PS Audio, Intl.

Making some noise

We’re starting part 2 of our continuing story of how AC power affects the quality of our hi-fi systems, how vibrations and microphonics do the same and then part 3 will be how we deal with them all together for great benefit.

In part 1 we learned how and why power affects the sound quality – and part of that learning showed us that without perfect DC to run our amplifiers, we get a not-so-perfect output feeding our loudspeakers. This is called distortion and the term distortion simply means a deviation from what we started with – an imperfect version of the original.

Whatever was on our disc, in the form of music, needs to be amplified without distortion to make perfect music in our rooms. In other words we need to transfer a perfect copy of what was on the recorded medium and get it into the room. The closer we get to perfection the better it sounds.

We know that if we have less than perfect power, our goal of a perfect copy of the music cannot be achieved because we’ve added or subtracted something from that music. The same can be said for another form of distortion: microphonics.

Microphonics is a well understood distortion but most of us don’t thoroughly understand it and, even if we did, don’t know how to minimize it effectively.

So let’s start with the basics and understand what it is. Microphonics is the tendency of something to act like a microphone picking up sound. A good example of microphonics might be a tube in a preamplifier. If you were to open up a tube preamp, turn the volume up high and flick your finger against one of the amplifying tubes, you’d hear the sound of your fingernail striking the glass envelope of the tube in your loudspeaker. That’s the tube acting like a microphone. Tubes are notorious culprits as are capacitors. In fact, just about everything in your analog hi-fi electronics is microphonic to some extent.

I remember an ad for software you could load onto a PC that turned any sound card into a microphone (without a microphone) and allowed you to snoop in on some poor unsuspecting person’s conversations. This worked because of the tendency of the capacitors on the sound card to act like microphones and if you amplify it enough you can actually hear what’s going on in the room.

Many modern microphones of the highest quality are actually capacitors optimized for full range sound recording.

Your DAC, preamp, power amp, CD player etc. are all microphones that pickup sound and add it to the music.

Interesting, eh?