Tag Archives: amplifier

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.

Terminology building blocks

One of the easier ways to get on the wrong path is to build an understanding based on piecing together little-understood terms.

A good example of this problem might be explained in my earlier post about dynamic range. Relying only on the measured numbers to achieve a more dynamic recording can easily lead to the opposite.

Or, making a purchasing decision on an amplifier simply because it has better measurements. The THD might be low but what about IM and AM distortions? Step response?

And if you get those right what about the sonic differences between JFETS, MOSFETS, and BJTs?

Or, if DSD is closest to analog wouldn’t it make perfect sense to then return to analog when mixing? Is that the best sounding course or is it simply the most logical?

None of us are going to be able to have a deep enough understanding of the complex technological world we have to navigate to make good decisions based solely on knowledge depth.

Instead, we need to rely upon our senses.

We need to listen. Use our ears as the ultimate arbiter.

Our senses don’t get tangled up in terminology.

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

Precise language

Navigating through the different types of communicators inside and outside the company can be challenging.

For example, when speaking to our engineering group we use what I would term precise language. In this vernacular, a rectifier vacuum tube is radically different than an amplifier tube. A thick film resistor sounds and performs differently than its thin film counterpart. The language is precise and one needs to shift gears from normal everyday interpretative listening to that of the specific.

When we change gears and respond to a customer’s request for help everything changes. We interact with a wide range of folks from electrical engineers to nuclear physicists to marketing managers to car mechanics. Each with a different knowledge base.

One great example of having to interpret what a non-engineer is attempting to convey can pretty easily be demonstrated with a look at our How to find and fix hum section of the website. After years of chasing our tails when someone emphatically insists they have a ground loop hum, we finally wised up and published two different audio files. One file has a 60Hz hum and the other 120Hz. One is caused by proximity pickup, the other from a potential ground loop.

The difference between the two is night and day when it comes to fixing the problem.

It’s taken a number of years for me to learn when to switch on and off my precise language filter.

How many misunderstandings have occurred because the listener hasn’t yet figured out how to switch on and off their precise filter?

What you say and what you mean are often understood differently.

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.

Matching specs

Imagine for a moment two analog gain blocks, each with identical input and output impedance as well as gain.

To make our little thought experiment more interesting, let’s also imagine their THD and IM measurements are identical as well.

Now, here’s where it gets juicy. Let’s imagine circuit A is a traditional high open loop bandwidth amplifier with lots of negative feedback applied to establish its gain. Circuit B is the opposite. Here we have a circuit with very low open loop gain with very little negative feedback.

Would the two sound different if we played music through them and listened on a highly resolving stereo system?

Having made this comparison more than a few times I can tell you my own findings are pretty clear. Indeed they do sound quite different, especially when the type of music we’re using has lots of rich harmonics and overtones played in a non-cluttered setting where those overtones can easily be heard.

It’s in fact not even a contest. Instantly noticeable and consistently the same even in blind testing.

But, why? What measurements might we apply to see those differences?

A differential null test?

Why haven’t we, as an industry, together created a measurement system that clearly demonstrates those differences on a measurable basis?

And even if we did, would anyone care?

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.

Who’s on first?

Making a decision as to which model of loudspeaker, amplifier, phono stage, or preamplifier can be daunting. There are more brands than one can count and, within those brands, many models.

In the days of dealers, we relied upon their curation skills to narrow the field. The only problem with that model is that most times big dealers carried not what they believed you needed most (after all, how could they?) but what worked best for them.

Fortunately, that wasn’t the norm in our small high-end industry. The dealers we loved and honored were those that stocked what they loved and eschewed brands and products that didn’t meet their standards. Those were the good guys in our industry. Personal pride and a love of audio drove their interests and formed their opinions.

Sadly, many of those heroes are gone. (Lyric HiFi recently announced the closing of its New York City store)

Despite the shrinking number of honest and heartfelt curators, it is still possible to cut through the cruft to narrow down the field to a few choices.

That happens through trust. Trust built through a magazine, an advisor, a reviewer, a manufacturer, or a friend.

Who’s-on-first gets less confusing when we’re working with people we trust.

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.

Side by side

I think most of us are comfortable with side-by-side comparisons. Take two stereo amplifiers and within the space of a few minutes decide which sounds more musical.

Easy peezy.

It gets exponentially more difficult when we make comparisons from memory because we each remember differently. For example, my memories of emotional responses are strong while those of specifics weak.

I easily remember how an amplifier made me feel or how engaged with the music I was. I can’t specifically name the details of what prompted those emotions.

This becomes particularly more difficult as it concerns loudspeakers. There’s no easy way to side-by-side compare loudspeakers. Even ignoring the obvious difficulties of moving in and out large heavy pairs of boxes let us not forget that where in the room one set of speakers shine another might fail.

Speaker setup is so particular to the room that it’s nigh impossible to do side-by-side comparisons of speakers.

Yet there are no more important pieces within our systems than loudspeakers.

And so we must rely upon our memories when it comes time to decide what speakers are best.

I hope yours is better than mine.

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.

OK, but not sure about this.

Watts watts?

A watt’s a watt, or is it? The technical definition of a watt is a unit of power, equivalent to one joule per second, corresponding to the power in an electric circuit in which the potential difference is one volt and the current one ampere.

To get a watt out of our audio amplifier we need voltage and current. Once we have that unit of power the magnetic motor system in the drivers converts that energy into movement that compresses the air and we hear sound. A watt is a watt, yet not all stereo amplifiers at the same wattage sound the same. So what’s going on?

Amps with identical wattage ratings sound different because moving watts are different than steady-state watts.

If we were instead looking at wattage steadily powering a lightbulb we’d not really see any difference if that watt was produced by hydro or steam power. But in audio, we don’t listen to steady-state tones. Instead, we’re listening to rapidly moving air pressure. How that air moves defines what we hear.

Thus, we’d be more accurate to suggest that the motion of watts is what matters, not the watt itself.


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.

Measurements can explain certain things regarding how an audio component might sound, but to design just around measurements is usually a bad idea. Paul goes into this a bit more deeply.

Beware the measurements

For readers of this blog, it will come as no surprise my thoughts and attitudes on measurements of audio equipment. Yes, measurements are important, but only when in concert with listening—and then too only if you look deep into those measurements to find out how/why what you measure sounds the way it does.

If you’re interested in diving deeper into this subject there’s perhaps no better way than to sit down with an experienced designer and have them take the time to explain how and why measurements simply do not tell you the whole story.

Take for example global feedback in an audio amplifier circuit. If we have an amp circuit with relatively high levels of distortion, we can simply wrap the output back to the circuit’s input and voila! lower distortion. The feedback is a fix-it mechanism correcting for the failings of an amplifier’s design. But at what cost? Nothing in engineering is free. Loads of negative feedback offer low distortion figures but at the same time, harden and constrain the sound. Knowing this is invaluable to a designer who can then ask the question, “what if we don’t have distortion in the first place?”

If you’re interested in diving deep with a designer, here’s your chance. Our own Darren Myers, one of the brightest and best engineers in the industry, spent a good hour and a half with John Darko in a great podcast titled, Beware the Measurements.

Have a listen and enjoy.


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.

Telephones to symphonies

We take for granted our ability to bring an entire symphony orchestra into our living room. We’re not arguing over whether we can or cannot invite the CSO over to give us their rendition of Beethoven’s 9th, instead, today’s debates are more about how close we can get to the real thing.

144 years ago, when inventor Alexander Graham Bell first came up with the idea of the microphone—the device that makes this all possible—I don’t imagine he envisioned where it would lead us. Bell, of the telephone fame, had, on March 10, 1876, successfully tested his first water transmitter, the precursor to everything we do and hear today in stereo.

A water transmitter? Well, more accurately, a water microphone. In this crazy contraption, sound waves cause a diaphragm to vibrate a needle up and down in water that has been made conductive by a small amount of acid. As the needle vibrates up and down in the water, the resistance of the water fluctuates causing alternating current in the circuit, and we get an electrical equivalent of sound. Remarkable.

It wasn’t until 10 years later that Edison build a better microphone using granulated carbon as the electrical generation element, but his efforts were only marginally better than Bell’s. It wasn’t until 1931—55 years later—that we’d get a microphone that resembles what we think of as high fidelity sound today. In that year, two concurrent discoveries changed everything. First, E.C. Wente and A. C. Thuras of Bell Laboratories introduced the dynamic microphone with a magnitude lower noise and higher fidelity, followed in that same year by RCA’s introduction of the ribbon microphone, one of the most widely used tools for the vocal recording and broadcasting industries. It was (and still is) considered by many as the most natural-sounding microphone ever made.

Today, the most widely used microphones for high-fidelity recordings is the condenser microphone, which, surprisingly enough, was also invented by E.C. Wente back in 1916. It wouldn’t be taken seriously until years later when amplifier technology had improved enough to make it work as well as it does today.

It is endlessly fascinating to me how everything we take for granted has such a rich background that the inventors likely never dreamed of. Certainly, Alexander Graham Bell probably never imagined his water microphone reproducing a symphony orchestra at the level we achieve today.

To him, it would likely seem like magic.


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.

Up or down?

There are HiFi systems that bring me up. They energize me, fill me with a desire to hear more and encourage upward volume level nudges.

And then there are the opposites, HiFi systems that bring me down: fatiguing, over etched, trying, encouraging downward volume level nudges.

One of the best means of knowing if your gear choices are serving you, if your system setup is satisfying, is this very test. Does your system inspire you to listen more or cause you to shrink back into silence after some play?

We may not be able to put a finger on the exact causes of either emotional response to music’s reproduction, but just knowing we can use this knowledge as a tool puts us in a heck of a lot better place for evaluating gear.

Home audio reproduction can cut both ways: a real up that energizes and inspires us or the opposite.

When you’re evaluating a new process, amplifier, cable, power device, or the system itself, be mindful of how you react to it.

Your emotional state, as a result of music’s immersion, can often be more telling than just about any other metric.


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.

This is an article written by Scot Hull from Part Time Audiophile that I totally agree with.

See www.parttimeaudiophile.com. It is always an enjoyable read.

One of my favorite hi-fi arguments involves stack-ranking your spend. That is, how should we spend our hard-earned money when assembling a high-end stereo system? What is the most important component? Is it the speaker? Is it the amplifier? Is it the turntable phono cable? In any of these debates, there will invariably be someone who says something like “the most important component in any audio system is THE ROOM.” Once this version of Goodwin’s Law plays out, there will be a lot of nodding and wise stroking of facial hair.

But what if it’s not true?

There is some sense to the notion, to be fair. We tend to build hi-fi systems in this particular “possible universe” and not others, so yes, chances are quite good that there will be a room involved. And yes, it’s true — rooms can dramatically impact the sound quality of any system. Room nodes, cancellations, reflections — all that (and a whole lot more) can contribute to a truly epic, or horrific, experience. For those keeping track, this is one of ten thousand reasons why it pays to make friends with your local area audio dealer.

But with that said, it’s pretty easy to overstate this. Common wisdom says that huge loudspeakers should never be crammed into small spaces. That low ceilings, or a narrow front-wall, or irregular side walls can “kill” the sound. That you need to “fit” your system to your space and never the other way around. That a goldilocks sprinkling of room treatments is the key “acceptable” sound.

This is all very sensible advice. It’s also a bit misleading, as anyone who has ever seen the listening room of a high-end audio reviewer will readily tell you.

Or anyone who has visited a high-end audio show.

Jeff Joseph, of Joseph Audio — for one notable example — is famous for his incredible-sounding loudspeakers AND for his off-center speaker setups. Going from room to room at an audio show, you’ll see room after room of very traditional, mathematically-plotted speaker setups — and then you’ll come to a Joseph Audio room and start scratching your head, and perhaps begin wondering if someone took their medication that morning. You then sit, your bemusement gives way to wonder, and you stop thinking about math, and “the most important component”, and start grooving to some world-class sound.

Would that system sound better in a better room? Maybe — okay, probably. But that doesn’t mean that it cannot sound amazing in your room, shitty though that room may be. Take a Vinnie Rossi demo, with some great big loudspeakers from Harbeth, the 40.2 Anniversary Edition. Big speakers, big sound, great-big-bass. And in Vinnie’s far-from-ideal-world hotel-room setup, those speakers sounded incredible. Yes, most of that has to do with Vinnie’s amazing audio electronics. But a lot has to do with the fact that the speakers have been pulled from the walls and are less than 5′ from your ears — best headphones EVER.

The point? Don’t give up because your room is suboptimal — almost all of them are — and chances are very high that you can and will still get amazing sound.