Cartridge Damping

In yesterday’s post about amplifier damping we covered what it meant and what happens when a power amplifier loses control of the loudspeaker – you get differences in amplitude that are anything but accurate.

There is another type of damping that I reminded of: cartridge damping. Phono cartridges have a problem similar (and for the same reason) to the loudspeaker damping issue but in reverse. A loudspeaker is a coil of wire driven by an amplifier while a phono cartridge is a coil of wire driving an amplifier.

So in a power amplifier situation we want the amplifier to have a low output impedance so that whatever changes happen in the loudspeaker coil don’t affect the output of the amp. In a phono cartridge setup we want the opposite – the amplifier to have a high enough input impedance so it doesn’t affect what the coil of the cartridge is doing.

A phono cartridge generates electricity in response to the movement of the needle in the record groove. This occurs because there is a magnet moving in concert with the record grooves in close proximity to a coil of wire. In the case of a moving magnet cartridge, the magnet is affixed to the needle and the coils are held steady in the cartridge while the magnet moves about. In the case of a moving coil cartridge the opposite is true – the coil of wire is affixed to the needle and the magnets are held steady by the head shell.
In either example it is then necessary to tame the impedance of the coil of wire in the cartridge either by adding a fixed resistor and capacitor across the coil or simply a fixed resistor. This process is called cartridge loading but more properly cartridge damping.

Phono cartridges act like any coil of wire producing a voltage differently per frequency. What we want is a constant output at any frequency so we damp the cartridge with resistors and capacitors. You’re probably familiar with the cartridge loading switches on the back of phono preamps like our GCPH.

Now you know.

Paul McGowan – PS Audio, Intl.

Damping Factor

The damping factor of a power amplifier is a metric used to describe the amplifier’s ability to control the loudspeaker. It’s basically calculated by dividing the amplifier’s output impedance into the loudspeaker’s input impedance when the speaker is operating near resonance. It’s a really important number to know when you’re making a decision on matching an amp to a speaker – yet you rarely ever see it mentioned these days?

I have been wondering as of late why? Is it because no one cares? No one knows what it means? I don’t have an answer to these questions but they’re good questions.

The long and short of this is that an amplifier with a low damping factor has trouble controlling a connected loudspeaker where an amp with a high damping factor is the boss in the amp/loudspeaker control battle. Moreover what’s detrimental to achieving a flat response from the speaker is when an amp has a low damping factor not all frequencies produced by the speaker are flat causing bumps and dips in its response.
Tube amplifiers, because they require an output transformer, have notoriously low damping factors which is one of the reasons they sound so different on various loudspeakers – some of this good, some of it bad – but all a matter of personal taste.

I would encourage a broader discussion on the topic as well as hope that more manufacturer’s of amps and loudspeakers publish both their imedance curves as well as damping factors.

It might spark some good conversation as well.

Paul McGowan – PS Audio, Intl.

Two types of Customers

I am convinced there are two main types of customers for high-end audio: dealers and end users. If you’re a manufacturer which customer do you design your product for? Both are absolutely valid.

Dealers have constant day-to-day communication with end users and collect all the info from them and then ask manufacturers to fill the needs of their customers.

End users know what they want and need and are the ultimate customer, but so scattered and varied are their desires that any manufacturer who designs for them has a huge challenge ahead to figure out what might appeal in a single product.

The dealer can act like a filter, while the end user can provide the ultimate answer if only one could determine which end user to pay attention to.
Most high-end companies I know choose the dealer route – they build products that are most requested by their dealer network – which reflect the desires of the dealer’s customer base.

It’s probably no surprise that we take a somewhat different course – an amalgam of both – but the final arbiter in the decision comes down to two criteria: do we want to own the products and are they extraordinary enough to deserve a life of their own?
Unusual? Yes. Weird? I don’t think so.

Paul McGowan – PS Audio, Intl.

Camera’s and Stereo’s

I am a photo buff. Have been shooting pictures both as a professional and an amateur for most of my adult life. I shoot with a fancy pro camera. I shoot because I love the process, the kit, the whole magilla. In fact, sometimes when I frame a shot in the viewfinder that floats my boat I get so excited I shoot it again just because it felt so good.

There are plenty of cameras today that shoot excellent pictures but I never think about using them because they are not high-end and don’t give me the same experience – even though they may give good results.
It occurred to me that there is a great similarity between high-end cameras and high-end audio – one that might be instructive to us. In fact, I have of late been using cameras to help explain what high-end audio is to people who ask me what I do.

I bought my wife Terri a small Canon camera that shoots 12 megapixel photos and produces wonderful shots on occasion – some rivaling mine from my 21 megapixel Canon 5D. In the same way I have heard wonderful music coming out of lower cost systems that did not have high-end intentions. So, what’s the difference? Consistency and trust.

When I see something I want to capture and I grab Terri’s little camera, I don’t trust it and the results usually reflect the lack of trust. It takes forever to snap the picture, I can’t control the exposure and focus to match what my mind’s view is relative to the camera view. When I pick up the 5D it’s instant, does exactly what I want and the results are 100%. In fact, when I look at the resulting picture I am always blown away because it’s usually better than what was in my mind’s eye.

If I take you into the PS listening room I am confident in what you’ll hear and experience. Can you get that same experience elsewhere? Sure, but not consistently and I do not trust you’ll have the experience representative of what we call high-end audio.
If you want the real deal – you gotta go for it.

Paul McGowan – PS Audio Intl.

Visionary vs Engineer

My friend Mark Levinson, the man not the company, is a visionary not an engineer. In fact, I doubt Mark knows how to design anything electronic yet his namesake adorns some of the best loved products in our industry’s history.

I find this fascinating because many people I run into seem to believe every nerd running a high-end audio company is something of an engineer – else how could that person lead the charge to create cool products we all want to own?

An engineering mentality isn’t required – in fact many time it’s a hindrance. Knowing too much sets up walls and rules that keep people locked inside boxes that are unimaginative.
The best visionaries I have ever met are simply frustrated power users. They know what they want, how it should feel and look when it’s done, what purpose it should fulfill and why it needs to exist. In many cases it’s the frustrated user that simply gets fed up not being able to do something so they go do it themselves.

Satisfying an itch to make something that perfectly fills a need no one else is thinking about is the essence of a visionary – the term seeming like such a lofty title when in fact, they are nothing more than a frustrated user.

We all benefit from the frustrated user that goes out and builds something that scratches their itch.

Paul McGowan – PS Audio Intl.

Give Me a Good Reason

There are plenty of products worth owning but only a very few worth buying and even fewer worth switching.

If you have something in your home that works you don’t have an itch to replace it – in fact, you probably never think about it because it works. When the opposite is true you’re on the hunt for a replacement solution.

So a product that is so extraordinary that it jumps out at you and makes you replace what you have that is working is rare indeed – and rarer still in an industry like ours that sees little true change in products and methods of reproducing music.
Most of what we see and get the itch to buy happens because what we have is getting tired or has been replaced with a newer technology.
This whole thought process just came to me while speaking to a group of Audiophiles on a recent road trip: the question was asked if we had anything extraordinary coming down the line I could share with the group. Of course I think everything we make is extraordinary but what the person was really asking was “is there anything that is worth me selling what I have and replacing it with what you have?”

That, my friends, is a much tougher proposition for any company.

Paul McGowan – PS Audio, Intl.

Narrowing down the Choices

If I walk into a restaurant and open the menu to be faced with 100 different choices: Italian, American, a little bit of this and a little bit of that I have learned it’s time to run and find another. In my experience the more choices on a menu the more mediocre the food will be on an almost one-to-one basis. And the same seems true with high-end audio companies. Those that seem to have everything for everyone tend to turn out fairly mediocre products.

Oatmeal instead of eggs Benedict.

I think this is a classic case of manufacturers trying to fill holes in the marketplace with products that meet a certain standard but aren’t exceptional – a trend that seems to be growing rather than shrinking in a tough economy.

At the proverbial end of the day it comes down to what you care about – building products for the marketplace or building products for the people that want to use them. That may seem like a semantic difference but I assure you it is not.

Most of us can tell when a product exists because it’s extraordinary and when it’s just there to meet a need. It may be tedious to ferret out the extraordinary from the mundane but I believe worth the trouble.

When manufacturer’s focus on building products they want to own and then find a group of like-minded people to sell them to, the world’s a better place.

Indeed.

Paul McGowan – PS Audio Intl.

So sorry, we have no banana’s

My little riff on power amplifiers and how I could tell I had a winner really sparked off a lot of comments and questions of where to buy or when it’s going to be available.

One of you even scolded me about being a tease without offering anything in return. Let me just suggest my intent wasn’t to try and sell you an amp – because there is no amp – but to simply share with you my excitement of discovery – as well as give you some insight into the process we go through to flesh out a new product.

There is no new amplifier right around the corner that I am building you up to get excited about: I wish there were. From the point of “paul’s excited” to “now you can buy one” is typically about a year depending on scheduling in the engineering department. Sometimes there’s a hole in the schedule we can squeeze something in and when that happens it’s down to a matter of just many months.

We do not build products to please our sales department who get inundated with requests for specific product types – we’re not a seasonal company that responds to marketplace pressures – instead we build products we want to own. I think that’s perhaps different than a lot of companies being neither right nor wrong just the way we are.

I would dearly love to bring this power amp into your home so you could experience what I am hearing – and someday we will.

Paul McGowan – PS Audio, Intl.

Slap in the Face

Yesterday I wrote about a new power amp technology that simply blew my skirt up to the point where I have cleansed the listening room of anything but this product to amplify the Maggies. The decision to consider doing this took about 10 seconds: I knew immediately this was it. I then spent nearly a week pinching myself to make sure it was real – a battery of tests, listening to cuts I formerly couldn’t stand to hear, new cuts I had never heard – all in an attempt to uncover the dirty little truth that what I was hearing was too good to be true. It is true, my fears unjustified.

What cues slapped me in the face to make this decision? How did I instantly know this was something extraordinary? I’ll tell you in this post but let me caution you that for serious listeners, the process is different for each of us. This revelation that we each know extraordinary performance in a different way took a lot of years and conversations to figure out – and during the process of realizing this interesting fact I had many troubling days filled with self doubt. Why didn’t I hear what someone else heard when it was so obvious to them and brushed right past me?

I think the answer lies in how we recognize patterns that relate to reality. My cues that tell me what I am hearing is live or recorded are probably different than yours. I am extremely sensitive to image placement and audible pattern memory. For example, when I am on my morning walk into work I can tell the location of sounds around me as well as instantly know what created the sounds – the starters on different cars are immediately obvious to me: Chrysler starters vs. Subaru, vs. GMC, 4 cylinder engines vs. V8′s, different birds, how the neighborhood I walk through normally sounds vs. anything out of the ordinary.

Others pay no attention to this but use other means to identify and register their surroundings every moment in the day. It is something we all do in our own way and when it comes to a high-end system and recognizing a good performance and a bad performance I believe the same holds true. We each hear something different that cues us into the window of “closer to the truth”. For some it’s pacing, others tonality, and still others it’s imaging. For me, I fall into the latter.

So when I switched on the new power amplifier module I was evaluating, which had been gain matched to within a 10th of a dB to the reference power amplifier, I almost fell over when the speakers literally disappeared. I don’t mean a little, but 100%. They vanished, no sound coming from them whatsoever and the music totally divorced from the source. Cut after cut I went through and the same thing occurred.
So concerned was I that something was wrong I had engineering check and recheck and still, it’s perfect in all respects.
This was a major slap in the face and I’ll keep you informed if anything comes of it. For now I am feeling a bit selfish listening and enjoying but heck, there’s gotta be some bennies to the job!

Paul McGowan – PS Audio, Intl.

Shaking Your World

Not often I run into something that simply shakes up my world and when that happens it’s hard for me to not stop everything we’re doing and shout it out loud. Thank goodness for this little blog – I can shout without disrupting PS Engineering.

Case in point the new power amp we have been working on. We haven’t released a new power amp in a couple of years because to date I haven’t heard anything that just knocked me out. Why is that important? Because no one in the company has any interest in building products just to fill a hole in the product line up. We build products because they deserve to be built. To date I haven’t heard anything that deserves to be built when it comes to power amplifiers.

But then …… an OEM manufacturer twisted our arm to give their new technology a listen and finally, after the device sat in the listening room for months, I finally got around to auditioning it. I was stunned. My world shaken so badly that I asked our chief engineer to take the unit back and run a full battery of tests on it so convinced I was that something must be amiss technically. And if so, I needed to know what it was because if technically incorrect then maybe we need to reevaluate what’s right and wrong.

But no, it was perfect, flat, correct. Identical in specs to every other amp we listened to. Identical to our reference amplifier in every respect except how it sounded. It’s back in the listening room, the reference amp retired forever. The new amp sitting open on a piece of plywood, sans chassis, with wires dangling about.

Tomorrow how I knew.

Paul McGowan – PS Audio Intl.