Turntables and Audio

Yesterday we gave a little history on the amazing invention of the “talking machine” that, for the first time in the history of mankind, allowed millions of people to enjoy music in their homes. And not just any music, but the music of the masters of that day. Imagine having the great Caruso singing for you whenever and wherever you wanted. What an amazing invention.

Introduced in the latter part of the 1900′s, a decade later Gramophones and Victrolas were in over half of every home in the Western World so great was their popularity – but then the bottom starting falling out of the market as another invention came onto the scene – and this one was leaps and bounds cooler than the turntable: radio, introduced in the 1920′s.

Imagine for a moment growing up in this era where the primary mode of transportation was either riding animals or trains, indoor plumbing is a luxury, gas lamps and lanterns still provide much of the light in homes and all of a sudden there’s a machine that spews out music on command – followed in less than a decade by most cities getting electricity, telephones, electric lights, the introduction of the automobile coupled with the idea of mass production to build them and the end of the animal transportation era. On top of all this add yet another even more magical and mysterious machine that plays music out of thin air! What a wonderful time to experience such huge magical changes.

Between 1920 and 1924 radio usage in the United States, the UK and much of Europe went from zero to over 60% of every home having one. Block parties were regular events and neighbors gathered for evening radio broadcasts of their favorite shows. The bottom on turntable sales dropped from everything to nearly nothing in just 4 short years. Both the Victrola (Gramophone) turntable and the radio were complete players unto themselves – the Gramophone 100% mechanical, the radio 100% electronic.

The Victrola company, faced with warehouses filled with unsold Gramophones made a momentous decision: they would combine forces with the folks at RCA and build a combination Gramophone and radio into one box. Revolutionary in its scope, little attention by the public was paid to the fact that this radio/turntable combination of 1924 marked the first electronic turntable ever made – and from that point forward, all major turntables went from mechanical to amplified in the blink of an eye.

Turntables and radios

Separate radios and separate amplified turntables were still available but the biggest sellers of the day and, for the next several decades to come, remained the combo we now call a receiver which even today still consists of a radio, an amplifier, a preamplifier and a phono input. Unlike the receivers of today, however, these console models included the tone arm and platter (now powered with an electric motor) to make a complete system.

It would take something really interesting to change people’s purchasing habits from this all-in-one console to true separates as we know it.

Separates

The separates category in high-end audio is one that is continually occupying my thought process. On the one hand the idea of multiple dedicated boxes allows us to add specific functions to our systems – each with its own independent ecosystem – in an attempt to wring out the very best sound possible in audio today. We can upgrade specific parts of our systems to the latest whiz bang without chucking the whole system. Separates are great!

On the other hand many dedicated boxes need to be connected together in a tangle of interconnects that are both expensive, unnecessary and probably sonically degrading. In the end, don’t all of us just want to play music and have it sound wonderful and impressive in our homes? Wouldn’t we love just one easy box solution that we come home to and enjoy?

Separates really have a unique love/hate relationship in our world of high end audio.

I thought we might spend a few posts taking a look at them anew (we’ve been here before) and question their value. To do this effectively let’s take a moment to go through a quick history of how we got here and why.

Hi Fi didn’t start out with separates. The first players were always complete because people naturally wanted something that just worked and I believe there’s no difference in this feeling today. But I jump ahead of myself.

Separates

When you look at this picture of an old and rare Victrola and realize it is not only a complete player but one that required no electricity to run you might scratch your head as to why I would include such an ancient device in this column on high-end audio. I’ll tell you. This marvel of music reproduction brought music to the world in a way that revolutionized everything we take for granted today. Before the introduction of the Victrola or Gramophone there was only live music and that music could only be enjoyed by a special few. Music for the masses did not exist until this player came into use.

At the height of the mechanical player’s popularity in the early 1900′s there were millions produced every year all over the world. Millions each year. I find this fascinating because within just a few short years of its introduction the world went from music-less to filled with music in the blink of an eye. The public’s hunger for music in the home was simply insatiable and I believe this event was on the same level as that of the invention of the printed book. In fact, I dare say the invention of the home music player might have been greater since everyone can appreciate music and back then not everyone could read. Literacy rates around the world were surprisingly low at the turn of the 1900′s.

How did this marvel of engineering work? In the same way a tin can “phone” works. Remember as a kid taking two metal cans, punching a hole in the bottom of each and attaching a taught string between the two and making a phone you could talk to your friend with? That’s how it works.

Separates

Sound pressure from your voice moves the bottom of the can back and forth and that movement is carried down the string and the receiving can’s bottom moves in like-response – re-pressurizing the air again so you hear sound. Now, replace the string with a needle and position the needle of one can into a soft wax or plastic material that is spinning underneath (in the form of a cylinder or a flat disc) and the mechanical movement is cut into that soft medium with the moving needle – all powered from nothing more than your voice. Voila, you have a record. Just reverse the process and you hear sound.

The sound out of our can isn’t very loud and we need to amplify it. That’s the function of the big horn you always see on these devices – it’s an amplifier. I am sure all of you have seen horn loudspeakers? That’s exactly the same thing still used today and many in the high-end swear by the sound of these horns. Others swear at them, but that’s for another post. 🙂

Separates

The point of this post is that music players started out as whole players because people who want to listen to music want something simple, elegant and easy to use. Tomorrow we progress a bit further.

Paul McGowan – PS Audio, Intl.
email Separates

Ketchup and separates

My good friend Jim Cohen is a world renown chef and makes the tastiest ketchup you’ve ever tried. Compared to Heinz or your favorite supermarket ketchup, Jim’s is just head and shoulders better than anything I’ve ever tried. We could easily say Jim’s ketchup is high-end.

Heinz is everywhere: it’s convenient, tastes good (not great) and soon it’ll most likely be even easier to use – I just read about MIT’s discovery of a new surface that is so slippery even ketchup won’t get stuck in a bottle anymore – and I’ll bet you money this’ll be the next reason they will urge you to buy bottled ketchup – not because it tastes better but because it’s easier to get out of the container.

So why are you reading about ketchup in Paul’s Posts about high-end audio? Because our society’s trend toward quick, easy, convenient vs. taste, experience and quality may well affect the future of high-end audio, separates and all that goes along with it.

Tomorrow we’ll start reflecting on the nature of separates in high-end audio: what their history is, what their value was and is and finally why this paradigm shift in our society is perhaps a good thing if we play our cards right.

Paul McGowan – PS Audio, Intl.

Getting Bass right

In yesterday’s post I discussed the fact that there are basically only two ways to connect a modern powered subwoofer: with a high level or a low level input. The vast majority of subwoofers today no longer offering a high level input because Audiophiles are probably ok adding another cable and with the rise of home theater applications as the primary market for subs, which require a low level input from the surround processor, the fate of the high level input has been sealed.

But what advantages did that high level input offer? Plenty and, to this day, it is still my favorite for integrating a sub with a system.

Let’s review what the differences between the two inputs are first. Fact is, both inputs actually go to the same place on a powered sub – they just take somewhat different routes. The high level input is designed to come from the main power amplifier’s outputs – which is typically 20 to 30 times louder than its inputs. Subwoofer designers merely take a couple of resistors and reduce this very loud signal down to match the main power amplifier’s input levels. If done properly the result is that there is no loudness difference between the low levelor the high level input signal that feeds the subwoofer’s internal power amplifier.

There is one big difference, however, and that’s the effect the main loudspeaker’s power amplifier had on the signal we reduced in level. Remembering that all power amplifiers affect the sound of the music that passes through them (phase shift at the lower extremes, tube amps with their output transformers, solid state amps, vs. class D amps etc.), we’d be much better off using the already-amplified output of the power amp to feed our sub because that output will be much closer matched, sonically, to what’s being fed to our main loudspeakers.

If we use, instead, the low level input directly from the preamplifier’s output we have not only lost the advantage of matching the amplifier’s sound but we risk the possible degradation of adding another length of interconnect to the preamp’s output which, in many cases, can do a lot of sonic damage (depending on the interconnect’s length and the preamp’s design).

So with all this in mind here’s my advice. If you’re forced to connect the subwoofer with its low level inputs, use a Y connector at the end of your interconnect cable feeding the power amplifier if the run is more than 2 meters.

If you’re handy with a few tools and want a better DIY path, just make a 30X resistive divider (use a 30K resistor and a 1K resistor) across the output of your power amplifier and feed the subwoofer’s low level inputs from the junction of the two resistors (the 30K going to the + output of the amp and the 1K going to the – of the amp).

Either way you go, you’ll be delighted you have a sub and connected it right.

Paul McGowan – PS Audio, Intl.

Feeding a sub

I was ready to jump onto a different subject than setup today but a number of you have asked me to at least touch on how to connect a sub and make sure it integrates properly in the system – which is interesting and surprising to me because I have come to learn most people don’t have subwoofers. Go figure. To me that means most people don’t have or know what true bass is, or don’t listen to music that requires it, or think they already have it. I hope that if you have a really good high-end system that you do, indeed, have proper low bass available to you for that extraordinary recording that requires it – and if you can achieve that without a sub, my hat’s off to you and your loudspeaker designer. Most people don’t know what they’re missing.

The thrill of having a pipe organ rattling your pant leg, the added realism of the flamenco guitarist and dancer combo pounding on a wooden floor – the impact of which is shaking your own room as if they were in it, the annoying air conditioner rumbling on the Cowboy Junkies Mining for gold intro when Margo Timmins is singing quietly in the church, the almost never heard New York subway rumbling past in an old Mercury recording in Carnegie Hall – are all part and parcel of what makes a good system a great system IMHO. And for many of us, we don’t have the required equipment to appreciate the added realism and enjoy these hidden treasures buried deep within our music. For that, you probably need a subwoofer.

But be that as it may, I’ll get off my soapbox and first take a look at the history, then take a look at some of the options and their good and bad points.

If you look up the word Subwoofer in Wikipedia, it credits my friend and former partner in Genesis Arnie Nudell as the inventor. The article suggests that when he, John Ulrich and Cary Christie (the founders of Infinity Loudspeakers) first introduced the Infinity Servo Static in 1966 – which coincidently is the same year I graduated from high school – the included servo subwoofer was the first to be sold commercially. I haven’t any clue if that’s true but what I do know is that because the Electrostatic panels that were used to create the Servo Statics did not have the ability to produce much bass, there really wasn’t any choice but to augment them with a separate woofer – if a full range system was to be created.

Whatever the facts are the subwoofer era, as an add on device to home stereo systems, was off and running and has been an essential category ever since. It lost favor for two-channel systems somewhere in the late 1980′s, early 1990′s but was revived again by the home theater crowd who are still the largest consumers of the category.

At the beginning of the subwoofer era, around the late 1960′s, most powered subwoofers had only a high level input that was meant to be fed from the main power amplifier output. This arrangement was created out of convenience, rather than necessity, as the actual wattage from the main amp was never used to power the sub itself. No, the powered subs with high level inputs took the output of your power amplifier and necked it down with a few resistors so it would match the same level as the input to the main power amp. The designers of these subs did this because it made it “easy” and “convenient” to connect the subwoofer since it was next to the main loudspeakers anyway.

As subs became more popular and as the home theater folks started getting interested, the low level RCA input was added as well as fancier crossover options, servos, setup guides, wireless connections, etc. Before too long we found a situation where almost none of the modern powered subwoofers have high level inputs anymore and they are almost all outfitted with a low level input only. Some companies, like REL, still have high level inputs on their loudspeakers – but it’s pretty rare.

Tomorrow let’s take a look at the advantages and disadvantages of both input types, then we’ll look at connecting them up.

Paul McGowan – PS Audio, Intl.

Music and rooms

Music and rooms

After reading through our series on rooms and tuning, my son Scott suggested I watch a video by Talking Heads leader David Byrne on how architecture changed music.

This talk, available on the wonderful TED Series, is an extraordinary piece of information and I was pleasantly surprised at what I learned.

If you have a moment give it a look. I think you’ll enjoy his ideas about how music evolved into its present form from Bach, Mahler, Mozart, Wagner to modern Stadium rock, it turns out the architecture of the rooms and the environment plays a significant role in what composers write and musicians play. I certainly learned a lot. http://www.youtube.com/watch?v=Se8kcnU-uZw

Paul McGowan – PS Audio, Intl.

Actually measure what you have

When I used to be a part of loudspeaker manufacturing at Genesis one of the tools we relied on the most was something called an RTA. This stands for Real Time Analyzer and while the one we used was part of a fancy computer program called MLSSA (Maximum Length Sequence Analyzer) it was, none the less, the most valuable tool we had in the toolkit.

The real time analyzer was used to get a broad measurement of the loudspeakers we were designing at the time. Into the loudspeaker you put pink noise (which is white noise rolled off) and then point the microphone of the RTA towards the speaker to see its on-axis and off-axis response.

I know you’re not designing loudspeakers but you are building a high-end stereo system and so it is very helpful to get a quick snapshot of your room’s response to your setup – or perhaps what your speakers are outputting in the room. Are you getting flat bass response? High end sagging? Well here’s a way to get an RTA without having to spend the thousands upon thousands of dollars most RTA cost.

There’s an app for it! Yep, now I sound like an Apple commercial but if you have an Apple device that accepts apps and an extra $11, you can buy yourself a handy RTA and it’s extremely useful. Just click on this link to see or type in “RTA” in the search field of your Apple device’s app store icon.

Definitely one of the better $11 purchases I have made.

Paul McGowan – PS Audio, Inc.

Lasering

Lasering

Our series on setting up your system for best advantage talked a lot about measuring and making sure your loudspeakers are spot on in terms of distance to the rear wall, distance to your listening position, equidistance toe in, setback, etc. All these measurements are quite critical because at higher frequencies the wavelengths can be measured in tenths of an inch.

One of the best tools I have cost me a whole $30 and I would encourage you to consider getting one or something similar. It is a cool little tape measure that also has a laser built into it that you can use to make sure something’s straight or lined up – and it’s lined up we’re most interested in.

Lasering

You can find these on Amazon (just click the image itself for a link) or perhaps your local hardware store.

Of course we all need a tape measure for the tasks at hand but perhaps more important is the laser included with this device. One of my readers made a great suggestion that I’ve been using for setup and that is to put this device on the front edge of your loudspeaker and then use the laser inside to point to the other loudspeaker. This will give you an exact placement so the two loudspeakers are absolutely symmetrical.

So imagine placing this on the front of the left loudspeaker and pointing it towards the right loudspeaker. If you’ve measured properly you’ll get a straight line of laser light in the exact same spot as you have the device – but the first time I tried this trick – even after careful measurement, the right loudspeaker was a full inch behind the laser light.

There are also laser levels, laser snap strings and a plethora of such devices that range from the very low cost to the very expensive. I would recommend adding one of these to your arsenal for setup.

Having the right tools can sometimes make all the difference in the world. Tomorrow an even cooler tool.

Paul McGowan – PS Audio, Intl.

The last link

As you can imagine, every room and every system and situation are different. It is nearly impossible to give good all-purpose advice that’s specific to anyone’s stereo system and what we’re trying to do in this series of posts is give you some generalized understanding of how everything works and interacts so you can tweak your system to best advantage.

In the spirit of understanding I’ll share with you today what I do in my main system to give you an idea of this one setup and what results I am getting by taking these steps.

The main PS Listening room is about 22 feet long, 15 feet wide with a 10 foot ceiling – your basic rectangular room with a high ceiling. In the room I have a pair of Magneplanar 3.6 panels for the main speakers, two Martin Logan Descent subwoofers and an original pair of Magneplanar Tympani 1D bass panels for a bit of midbass fill. You can see in this picture the source equipment is to the side of the room so we can easily access it and the amplifiers are in the rear behind the Tympani bass panels. One long pair of XLR balanced interconnects tie the PerfectWave DAC to the power amplifier in the rear and behind the Tympani’s.

The last link

You will also notice the forrest of white tubes that line the walls. These are DAAD’s (Diffusion Absorption Acoustic Devices) that our friends over at Avalon loudspeakers distribute. What you don’t see is that between the rear DAAD sets are also 4 RPG diffusors as well.

The DAAD’s are great – but very expensive – and the RPG’s much more affordable and, frankly, nearly as good. When we go to a show I usually bring only the RPG’s to place behind the loudspeakers.

I spent several weekends rearranging everything using the exact same guide I have presented to you in this series of posts to get this to sound right from both a tonal standpoint as well as imagining properly.

Perhaps the single biggest improvement I made was the careful placement of all these diffusors. Without this forrest of acoustic reflecting traps, or at least a few of the RPG’s in the room, the sound is not remarkable at all. Add them into the mix and then there’s magic where the music just floats, the tonal balance is nearly perfect and I can hear any subtle changes in cabling, amplification etc.

This is, after all, both a pleasure den as well as a working lab where we test all manner of changes to our equipment before it goes out for sale – so it is important that small changes in even the tiniest of areas be obvious to anyone listening. But more to the point of this guide, how does it sound? I think everyone that’s heard this system finds it to be a real jaw dropper. The music is effortless and completely divorced from the loudspeakers themselves. The soundstage goes back beyond the rear and side walls and instruments have a fulness and naturalness of timbre and tonal correctness that always puts a smile on one’s face. It’s a real treat to hear this system.

To set this up I always remove every piece of room treatment, as I mentioned in the first article in this series. I then first add the side traps you see in the picture – which is the first reflection points we discussed yesterday. I next go one by one attending to the rear wall and going through the tedious process I described before: how does it affect the single vocal? Better or worse? Get that right and placed well, then check with the more complex orchestral piece – paying particular attention to tonal balance of the instruments and the space around them. Then start adding more, less, whatever seems to get me closer to the ideal – but absolutely being rigorous and methodical in the process.

I think it is this methodical approach that, at the end of the day, gives any of us the best chance at getting it right. Take notes – either mentally or physically – and learn what moving this, changing that, adding this and deleting that do to your test pieces and over time you’ll know your system really well.

I hope you’ve found this series of value. If I can help you in any way let me know.
email The last link

Paul McGowan – PS Audio, Intl.

I’m so diffused

The first time I can remember anyone paying attention to room treatment was back in the mid 1970′s when the local manager of our Pacific Stereo store added a brick surface to the wall behind his loudspeakers, a pair of Bose 901 Direct Reflectors, in an effort to provide a “perfect” reflective surface for the Bose. The system screeched like a wounded owl and required either a lot of alcohol or a quick exit from the room to enjoy the results.

The industry and knowledge base has come a long way in the many years after this first encounter: due mostly I would imagine to the high-end borrowing from the recording and pro folks who have used some form of room treatment for decades before anyone in the high-end figured it out.

There are two main schools of thought when it comes to treating a room: absorbing or diffusing or a bit of both. Many devices created for this task have both a reflective and an absorptive surface that can be employed in the service of making the room a friendlier environment for our stereo systems.

Absorbing the sound is a near impossible task because you pretty much can’t absorb all frequencies. Absorbing the higher frequencies is rather easy but as the frequency of the music gets lower and lower it becomes increasingly difficult to absorb and eliminate the sound. Furthermore, it seems to me to be the wrong idea if we’re considering the room as our friend we want to include it in the system instead of fighting it at every turn. I think diffusing the sound is by far the best way to go.

Diffusing the sound scatters the sound in such a way as to allow your ear/brain mechanism to pay less attention to it than the directly received sound. This allows us to ignore (or reduce our awareness) of the scattered sound in favor of paying attention to the more direct sound – kind of like what we want to achieve with absorbing without having to use such brute force measures as are required with any absorber type of system.

One of the first tasks we’re going to start with is to try and eliminate the point of first reflection from the sidewall. This is the classic area to start with assuming you’ve placed a throw rug or some type of absorbing material on the floor in front of the speakers (diffusing on the floor is nearly impossible from a practical standpoint) and the ceiling is pretty far away. If the ceiling is as close to the speaker as is the sidewall you may wish to explore the idea of repeating the process we’re going to next suggest – on the ceiling.

For this exercise you’ll need the help of an accomplice holding a small mirror that isn’t overly concerned with looking a little goofy. First, remove the grilles on your loudspeakers. While you’re seated in your listening position, which was set in the procedure we detailed in yesterday’s post, have your cohort stand with his/her back touching the sidewall in front of the speaker, perhaps halfway between the speaker and your seating position, holding the mirror directly in front of them and parallel to the sidewall behind them.

You want to look at the image in the mirror and have them move toward or away from the speaker until you see the speaker’s tweeter in the center of the mirror. This is the point of first reflection where the sound from the tweeter and midrange first strike the wall and then point towards your ears. Because the distance traveled from the loudspeaker to your wall and then to you is greater than the direct sound, you hear a slightly delayed version which confuses the image. So it is at this very spot you need to diffuse the sound so no longer is your ear/brain confused. The improvements in imaging can be significant.

A good diffusor is important but almost anything will be better than a bare wall.

Tomorrow I’ll discuss what I use and recommend for diffusors.

Paul McGowan – PS Audio, Intl.