Tag Archives: preamps

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

For phono stages and preamps, external power supplies are almost always best. I recently replaced a high quality wall wart power supply for my Dynavector P75 Mk4 phono stage, with a large, well regulated external supply, which sends DC to the phono stage electronics themselves and was able to squeeze even a little more quietness from my Well Tempered Labs turntable rig.

External cures

From as early as 1980 it had been clear to us that the bigger the power transformer the better the sound—a fact that at first didn’t make a whole lot of sense.

Why would a preamplifier that consumed no more than a few watts benefit from a power transformer capable of 100 times that?

Impedance.

Turns out that because bigger power transformers have thicker wire they have lower impedance, thus less modulation.

An easy way of visualizing the difference between high and low impedance transformers would be something akin to spongy vs. brick wall. A spongy power transformer is malleable by the load—or in our case, modulated by the music. A bigger transformer is less affected and thus is impervious to being pushed around by the amplifier’s circuit.

Once we recognized the importance of the power transformer we began implementing bigger and bigger ones until they no longer fit into the chassis, prompting us to begin offering external add-on transformers. Here’s one of the first we ever produced:

While we as the designers and manufacturers of our products could choose any size transformer we wished, that certainly wasn’t the case for others who had already made their choices and now their products were out in the marketplace.

This brings us back to the problem I was facing in the late 1990s when I hoped to come up with a way of improving power supply performance of products not our own.

Would it be possible to externally increase the size of an internal power transformer? And if we could, how about those power supply capacitors inside? Any chance of adding more capacitors without opening the case?

Seemed at the time like more of a fairy tale than possible, but…

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Recording vs. reproducing

As Octave Records grows it’s becoming more evident to me the difference between recording and reproducing.

On the former, we’re often using heavy hands to capture as best we can what happens in acoustic space: different microphones, preamps, EQ, reverb—everything we would never consider in the act of reproduction.

I think of recording as building a movie set. Hours, sometimes days are spent assembling all the pieces together so that the final image perfectly represents the vision in one’s head. We’re not as interested in being faithful to the moment as we are true to the vision. The best recordings use whatever is available to them to capture the perfect sound.

The opposite is true when it comes to audio playback. The best lenses and cameras, like the best audio reproduction chains, are built with only one goal in mind: to be faithful to the original.

It took chisels, hammers, and heavy hands to fashion from a block of marble Michelangelo’s David, but once crafted, very different apparatus to enjoy it.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Over the top

When it comes to having company over for dinner my family’s general rule of thumb has always been better too much than too little.

Too much at the dinner table just sets the stage for lunch leftovers. No big deal.

But when it comes to your HiFi system, too much can be…dare I say…..too much.

As audiophiles, we can fall into the trap of pushing the improvement envelope too hard: adding DSP or an equalizer when all we really needed was some time and elbow grease. An add on super tweeter or perhaps one of many aftermarket tweaks guaranteed to make everything that much better.

It’s always tempting to turn what’s great into something even better.

In my experience, those add-ons are short-lived.

If you’re looking for better, always start with the basics: loudspeakers, power amplifiers, preamps, and sources, such as turntables and DAC’s.

A lunch of leftovers is easy.

Unloading to the used market unnecessary add-ons gets painful.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl

AC receptacles

For those of us with long memories here’s a flashback. Remember when preamps sported rear-mounted AC receptacles to power the rest of the stereo system?

The first memory I have of the rear-mounted AC receptacle was on my father’s McIntosh C28 preamplifier.

Note the use of switched and unswitched outlets. The idea was that unswitched outlets were for the power amp and switched outlets for tuners and tape decks.

What a grand idea. Run your entire stereo system including your power amplifier through a skinny 16-gauge 2-wire zip cord.

What was it Red Fox used to put his hands up towards the heavens and cry out?

“Elizabeth! They’re coming for me.”

Some innovations are better left in history’s dustbin.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Tinkering

One hundred years ago a tinkerer was a traveling craftsman skilled in the art of metal repair. He would be invited into homes to repair eating utensils and small metal objects.

Today, in our disposable society, there’s no need for a person to repair a mangled spoon or a fork’s broken tine. We just throw it out and replace it.

A more modern usage of the word tinkering might apply to an audio purist’s quest to build a musical system. A modern tinkerer will mix and match stereo components, tweak and tune an audio system until reaching a new level of purity.

When it comes to high-end audio I cannot think of another personal pursuit that so encourages tinkering. Most endeavors support the use of pre-approved (often brand-specific) components: Canon lenses on Canon cameras, Tesla swag on Tesla cars.

Not so much HiFi. DACs from one manufacturer connect to preamps from quite another and both interconnected from yet a third vendor.

Mixing and matching, tinkering and adjusting, tweaking and tuning.

It’s part of what makes our passion so unique and our results so personal.

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl

Something for nothing

We all like something for nothing: the extra scoop of ice cream, the baker’s dozen, the unexpected set of vibration canceling feet included with our new amp purchase.

Rarely are we pleased with the opposite—something intangible for plenty more. Yet, this is the conundrum we face when considering headroom.

Headroom in amplification—both preamps and power amps—offer huge benefits that we never notice until they are missing. Compare a low headroom amplifier with its polar opposite and the problems of compression, increased non-linearities, and eye-squinting strain become apparent.

It’s not easy to plunk down more funds for greater headroom because it requires a leap of faith, and faith is something we all struggle with.

It’s often the invisible we benefit from the most.

 

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Pauls post reminds me of a joke I heard at a MD’s convention a few years back. The Audiophile version of this applies and would be the following:

If you ask 10 Audiophiles how to set up a system, you’ll get 20 answers as each of them would eventually change their minds, at least once.

Holograms

There are numerous aspects to the high-end audio system: tonality, resolution, inner detail, micro, and macro dynamics, and of course, the holographic image.

Whether your system provides little more than the basic phantom center channel or a full-on three-dimensional holographic soundstage, you’re always dealing with an audio hologram.

A few days ago I wrote about the importance of not cluttering up with equipment the space between the loudspeakers. That’s important for two reasons. First, our sources and preamps are sensitive to microphonics. We should get them as far away from the speakers as is possible. Second, that clutter of equipment visually interferes with the hologram.

Whether we like it or not, our vision is often a distraction when it comes to generating a perfect audio hologram. It’s why it sounds better when we lower the lights or listen in the dark. Once our visual distractions are removed, the brain can more easily process the deep, tall, and wide soundstage that lurks behind our loudspeakers.

Of course, not all setups have managed to build the proper holographic image where the speakers have disappeared, and the musicians are standing behind them. But, on a proper system, this holographic image can be breathtaking—an essential element in a great high-end rig.

If your HiFi doesn’t image the way it should, consider removing physical and visual clutter from where you hope the phantom soundstage will appear.

If it hasn’t a place to exist, it likely will not.

 

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

I’ve used two passive “preamplifiers”, one of which you could activate an active stage, for more gain. I don’t use either now and probably wont ever again.

The potentiometer preamp

A preamplifier is, as its name implies, an amplifier before an amplifier. Preamps are typically placed between the source and the power amplifier. They select inputs, control volume, and amplify the signal to a level acceptable to a power amplifier. Simple, right?

Then comes along the idea of a passive preamplifier which is an absolutely incorrect usage of the name—a faux pas we at PS Audio did our best to correct. You see, to qualify as a preamplifier, you need to actually have an amplification circuit to…wait for it…amplify.

So, many years ago, in the 1970s, Stan and I used only an attenuator between our phono preamplifier and power amplifier. In our judgment, nothing was cleaner than a simple potentiometer or stepped attenuator to vary the volume. And we were correct, though cleaner doesn’t always mean better.

When it came time in the evolution of PS Audio to launch our own preamplifier, the debate between us was fierce. Passive or active? In the end, we settled on both and offered a switch for the user to choose between passive or active. But Stan, ever our beacon of straightforward naming, could not bring himself to call it a preamplifier since it was and it wasn’t, depending on the position of the switch. This drove me endlessly crazy as my vote was for simplicity—our customers wanted a preamplifier, dammit! call it a preamp. Eventually, we reached a compromise and called it a Control Center and, thus, the Linear Control Center was born: a preamplifier with the switch in one position, a passive control center in the other.

I believe after all these years that Stan was right and I was wrong to have argued in favor of simply calling it a preamplifier.

If it don’t amplify…

 

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

If it walks like a…

When we think of products in terms of functionality they’re all somewhat the same. DACs convert digital to analog, power amps drive speakers, preamps control the level. But, that’s often where the similarities end.

How a product does what it does makes all the difference in the world. The output of an R2R ladder DAC and a DSD-based DirectStream DAC may look the same, but they’re not even close in how they got there—nor in how they sound.

The same is true for power conditioners. They have AC power going into them, and with multiple AC sockets at their outputs, some modified form of AC coming out. To say or even suggest that a power conditioner or isolation transformer has anything other than form factor in common with a Power Plant would be grossly incorrect. Yet, it happens all the time.

We invented the Power Plant concept in 1997. Since that time, 23 years ago, one of our long-standing life’s missions has been to help people understand the black and white differences between an active AC regenerator and a power conditioner. The only thing the two have in common is one AC input and many AC outputs.

Because Power Plants provide instant dynamic voltage and current regulation along with rebuilding the AC sine wave itself, they are unflinching in their rock-steady delivery of AC power to equipment. A power conditioner, on the other hand, does little to justify its namesake. The condition of the power through a conditioner is, for the most part, unchanged—except to have made it slightly worse in the very areas a Power Plant makes it better. Impedance. (this too applies to isolation transformer based conditioners as well, though they are closer to their namesakes in that they do isolate)

Active voltage and current regulation are the keys to reversing what many people fear most with the addition of a power conditioner—loss of dynamics and life. Those who have figured out they’re likely better off plugging their power amps directly into the wall socket rather than cripple them with a conditioner, isolation transformer, or any passive device, have exactly the opposite reaction when listening through the lowered impedance of a Power Plant.

Just because it walks like a Power Plant, it certainly doesn’t sound like one.

 

Asheville, Walnut Cove, Biltmore Forrest and Western North Carolina’s Audio and Home Theater specialists present Cane Creek AV and Paul McGowan – PS Audio, Intl.

Tube time

As I look out my office window I see tufts of melted snow, bare trees, a busy highway of squirrel traffic gathering whatever it is they store for the winter, and our cute, red, neighborhood fox keeping those same squirrels from overrunning the place.

It is fall and soon to be winter.

That’s the perfect time for me to run through Music Room Two and Three and change out all the tubes in the BHK amps and preamps. I use the cold of fall as a reminder to swap out the year-old vacuum tubes for new fresh ones.

Over time, vacuum tubes tend to lose some of their life, vim, and vigor. It’s a slow loss, one you don’t notice until a year has passed.

The fun of upgrading the tubes comes with the first listen. Wow! Time to go through all that new music you accumulated over the summer and relisten with the new fire bottles in place.

If you have tubes in your equipment, it might be worth thinking about changing them out for a fresh pair.

Fall is Tube Time!