Subs

In yesterday’s post I mentioned I added a single sub to the setup in Music Room 2 and got great results.  Several of you asked me why I didn’t add two, which is always my stand on subs, and where I got the sub.  I wanted to also touch on how I connected the subwoofer as well.

Indeed, whenever possible, two subs are better than one – but not necessary.  The advantage of a separate left and right sub is primarily in the setup of the room – one on each side makes placement of the sub actually easier as it takes over the room better at those lower frequencies.  Further, if you need to run the sub at frequencies higher than 80Hz (perhaps you have a pair of bookshelf speakers) or would prefer to have a gentle rolloff on the subs low pass filter (determines how high the sub goes) then the sound of that subwoofer can start to become a bit directional.

So my rule of thumb regarding subwoofers is to keep the subwoofer from going too high, hopefully never higher than 80Hz, keep the slope of the low pass filter to no less than 12dB/octave and adjust the sub level so it never stands out by itself; instead it helps the main speakers sound as if they have deep bass.

If you’re using a single sub, never place it between the two main speakers, always place it either to the left or the right of the mains and NEVER rolloff the bottom of the main speakers.  By this I mean many subwoofers have an in and an out set of connectors where the output connectors on the subwoofer are called a high pass filter.  This filter is used to make sure the main speakers don’t have to work as hard going down in the bass area – and allows the subwoofer to do the work instead.  This notion of rolling off the main speaker’s bass response was popular a few years ago in home theater circles, but trust me, it’s not a good sounding plan.  Let your main speakers do what they were designed to do and use the subwoofer to fill in what they don’t – and almost no full range loudspeaker gets down to 18Hz with any authority so you pretty much need a sub.

With respect to connecting the sub, in many cases I prefer to use the subs high level inputs and tap off of the main power amplifier’s output.  This method doesn’t use any of the main power amp’s wattage – just its output signal – the sub’s power amp doing all the work.  What it does accomplish is two things: removes the extra cable load off of the preamp or DAC feeding the sub and helps maintain the sonic characteristics of the main amp giving you a more seamless blend.

The subwoofer I am auditioning is a new product from a Colorado based company that is extraordinary, but they did not include a high level input.  I had to make my own and tomorrow I’ll tell you how.

Paul McGowan – PS Audio, Intl.

Finishing touches

I was up late two nights ago, as you may have read, dialing in the speakers in Music Room 2.  The speakers are a pair of Thiel 2-ways, using their coaxial driver arrangement.  These are simple, well designed loudspeakers which are a perfect contrast to the giant Infinity IRS in Music Room One.

Some of you may remember I explained that there are really only two perfect means of building a loudspeaker system: an infinitely small point source and an infinitely large line source.  The IRS is as close as anyone’s gotten (IMHO) to a practical line source and the Thiels are a pretty excellent point source – and while not infinitely small – their 5.5″ main driver and tweeter are about as close as you can practically get and still have reasonable frequency response.

To finish the installation in Music Room 2 I had to both augment the bass response and add a couple of corner traps.  Here’s a picture of what we wound up with.

Music Room 2 Finishing touches

Note the three RPG diffusers between the two loudspeakers as well as the DAAD corner bass trap.  Also note behind the right loudspeaker the hint of a subwoofer.

The Thiels are quite bass shy and would never qualify as a full range loudspeaker under any conditions I am aware of.  But that’s ok as I set these up over the last few days to have great imaging, a solid center fill, wonderful tonality and all that’s lacking is bass from 80Hz on down to 18Hz.

You might wonder what I used for a subwoofer and I can tell you that this is always a hard choice.  While there are many great subs around, few have met my criteria for subwoofers as I am (admittedly) a sub-snob.  When I add a subwoofer to the system In never want to hear it – ever.

Friend Neil Rosenblum from Florida recently sent me a slew of CD’s to audition (thanks Neil!!) and I immediately put Brian Bromberg’s great CD “Wood” on to test.  Track one of the CD starts out with Bromberg playing the bass solo and you’d swear he was in the room.  I brought several PS’ers into the listening room, played the track and asked where the bass player was “He sounds like he’s in those wooden things (the RPG’s)”.  Turn off the sub and everyone’s jaw dropped – it now sounded like a toy bass.

If you can keep the frequency of the sub low enough and DO NOT roll off the main loudspeakers, you can achieve amazing results – but you need a great subwoofer.

I have discovered an amazing subwoofer, built here in Colorado that I am testing out.  Wow.  I’ll tell you about it later – but this sub isn’t going anywhere.

Here’s another view of the room.

Music Room 2B Finishing touches

Now that the system is up and running and tweaked in, powered by nothing more than a 100 watt per channel PS A100, I put on another CD that was suggested by a reader, Madonna’s Immaculate Collection, track 8 and cranked it up.  The sound is more than wall to wall and it’s as if the little Thiels can reach down into the depths of the synth bass and go forever.

Lastly, if you look at the equipment rack you’ll note an empty space where CD’s have collected – that’s where a new turntable is going to be installed soon.  This means we now have two fully qualified music rooms we can use to audition just about anything we manufacture or when someone comes by to try their equipment on.  If you’re in the area, I encourage you to drop on by.

Tomorrow I’ll cover how we connected the subs.


Paul McGowan – PS Audio, Intl.

Tuning out probelms

If you had a chance to read yesterday’s post you’ll remember we’re in the process of setting up Music Room number Two, where we have a pair of floor standing 2-way Thiel loudspeakers.  That room is considerably smaller than Music Room One, measuring 12 x 15 feet, compared to Music Room One’s 15 x 23 feet dimensions.

Because of the room’s layout, relative to its entrance door, we are forced to place the loudspeakers on the short wall, giving us only 12 feet to work with for both loudspeakers and listeners.  I like this setup because it is perhaps more typical of rooms that many of you might have and suggests problems that are similar as well.  I typically like pointing the speakers into the long dimension of the room to give more space for both the listener and the system but, as many of you no doubt experience as well, circumstances just prevent that option.

In this setup it is not going to be an option to use our classic rule of thirds, which would place the loudspeakers 4 feet away from the wall behind them and the listener with 4 feet behind as well.  This wouldn’t work because you’d then sit a mere 4 feet away from the loudspeakers and that’s far too close – it’d be like wearing the Thiels as headphones.  I like to have at least 7 to 8 feet between the listener and the speakers.

So the first choice comes down to placement of both the listener as well as the loudspeaker and which is more important.  In almost every case the loudspeakers must be removed from the rear wall if you’re going to have any chance of making this work.  By default, this means the listener must sacrifice their space behind them.  The reasons for this are fairly straightforward: with but few exceptions, loudspeaker designers voice their speakers away from any wall boundaries and getting them too close to a wall changes the tonal balance of the speakers.  Several exceptions to this have been presented over the years, I believe Naim has a loudspeaker pair designed to go up against the rear wall, but generally this just isn’t true.

As you move a pair of loudspeakers closer to the rear wall lower frequencies tend to become louder, relative to higher frequencies, because the wavelength of the lower frequencies is longer – thus the wall reinforces the waves that bounce off of it – in a manner similar to an acoustic horn (the higher frequencies tend to go straight ahead and don’t get reinforced).  You can hear this effect easily if you listen to the tonal qualities of your voice changing as you walk into a wall (careful now).  Getting the speakers too close to the rear wall also changes, rather dramatically, the imaging of those speakers – with depth of soundstage increasing as you move them away from the wall – but getting them too far into the room has downsides as well.  Point is, you have to get them in an optimal place, relative to that rear wall.  In our case, we’re out from the wall about 4 feet and as we place our listening position up against the wall behind the listener, we’re at approximately 8 feet from the front of the speakers.

In such a small space we’re going to have problems with both imaging and tonal balance.  I mentioned yesterday that I am having trouble getting the same measure of soundstage depth as I have with the IRS in Music Room One.  I have followed the process I wrote about yesterday, and gotten good results but nothing to write home about – and my ultimate goal is to have a miniature version of Music Room One in Music Room Two.  So what to do?

If you’re battling a room, which is exactly what we’re doing given the compromises I’ve described above, then your next steps are to help the room and that’s exactly what I did to fix the depth problem.

I’ll go over those steps in some detail tomorrow.  For today, let’s absorb a simple rule of thumb: if your room dimensions allow you to use the rule of thirds with the speakers at least 7 feet away from your chair, you’ll get 80% of what you want without room tuning.  If you’re room is small enough to negate the opportunity for the rule of thirds, as just described, then you’re only likely to get 60% of what you want without room tuning.

In my case, we’re going to have start tuning.

Paul McGowan – PS Audio, Intl.

Basic Setup

So now that we know our musical library fairly well, what do we do with this new-found information?  How do we use this familiarity to help us affect change or experiment with different settings?

I’ll begin to walk you through a simple setup that I might be working with as an example so you can see.

We have two music rooms at the office, number one and number two.  In Music Room One we have the big reference system I have been writing about, based upon the Infinity IRS.  This sets the standard within the building and what we use as our go-to music setup.

Music Room Two is much smaller and more like something you’d possibly have in your home.  I am just now installing a pair of Thiel two-ways (SCS4-T) into the room.  There’s no possibility they will ever sound like that of Room One – and that’s never been the intent.  However, I do want them to have the same characteristics within their limitations and this is what I set out to do.

The first type of music I put on in either room is something simple with a voice.  Voices are for most of us easily identifiable relative to an instrument.  Let’s use our Diana Krall example again.  In Music Room One I get a clear sense that she is halfway between the front of the loudspeaker and the wall behind the speakers.  Her voice hovers in perfect space at about the right height and size (as long as I have the volume set properly).  The room she is playing in sounds to me a certain size that I am sensing.  That’s about all I need.

I play the same cut in Music Room Two and it shouldn’t take too long to reposition the Thiels to achieve the same basic feel.  What I am changing is the distance between the wall behind the loudspeakers, the distance between the pair and the toe in angle of the speaker.

  • Distance of the speaker pair from the wall behind them controls the amount of depth or space we allow to help the illusion of soundstage.  Pulling the speakers away from the rear wall too much loses the soundstage boundaries and palpability; too little and there’s not enough “space” for the soundstage to exist.  The soundstage should always appear behind and at the loudspeaker pair, never in front.
  • Distance between the pair controls the width of the soundstage, the center image and, perhaps more important, the tone of the voice.  Closer together the upper midbass is coupling better between left and right and the voice becomes fuller sounding – further apart the opposite.  You want the perfect balance.
  • Toe-in (angling the speaker pair inwards towards your listening position) puts the tweeters in a more direct path with your ears and will help solidify the center image.  Always use extreme caution with toe-in as less is usually better.  I try never to toe-in if I can avoid it – preferring instead to play with the distance between the two speakers until I get the best I can between proper tonality and palpability of the image.  Once that’s dialed in as best I can, then (and only then) do I judiciously toe in to achieve the finishing touch on image stability.  Too much toe-in can flatten out the depth and width of the soundstage you worked hard to achieve.

If by these methods I can get a close approximation of what I remember the track sounded like in Music Room One, I am halfway there.  Unfortunately, I cannot get the same illusion of soundstage from the little Thiels no matter what I do.  So what’s my next step?

Tomorrow we’ll look at what we can do to improve the Thiel’s performance as we roughly dial them in to sound similar to the IRS.

Paul McGowan – PS Audio, Intl.

Intimately familiar

I mentioned yesterday that the first step in setting any system up is to get to know your music well.  This can serve you in many ways: including bringing your collection of music to an audio show to hear what it sounds like.  This only really works if you’re intimately familiar with a certain cut of a disc.

So what does “intimately familiar” mean?  Does it mean you’ve memorized each and every note and know exactly what that sounds like – and look for the same on a new system or following a change you’ve made to your own?  No.  It means learning an overall feel for the piece – an overview if you will – focusing on the big, rather than the minute.

For example, my friend Rick Becker wrote to me the following “I find it interesting that some recordings produce an ‘I am there’ imaginary response, while other recordings produce a ‘They are here (in my listening room)’ imaginary response, usually dependent upon the recording technique”.  Well said and it helps explain what I am referring to – because Rick is taking in the overview of the piece and how he relates to it.

We’re all a bit different in what resonates with us in the quest for better sound – and how our sound memories work – but if we try and relate to the big picture of a piece of music and focus on the way the music makes us feel, whether it’s great for toe tapping, or perhaps as Rick puts it “the musicians in your room or you in theirs” or distant, or thin vs. fat, real vs. recorded.  It’s as if you’re writing a mini review in your head.

Learning this technique will prove invaluable to you for judging equipment, rooms, setups.  I was at an audio show and walked into a room where they were playing a cut of something I am extremely familiar with and it sounded completely out of whack.  I wanted to go over to the setup guys and change things – I could have fixed that system within 10 minutes because what was wrong was so obvious to me – but of course that would have been out of line and I kept my mouth shut.

The point is this: I knew the cut so intimately that I could have finged around with just the speakers enough to get it right.  Only my intimate knowledge of this cut made that possible.  So learning your library – from an overview perspective – is key to starting your quest to better sound within a given room.


Paul McGowan – PS Audio, Intl

Getting ready

I promised we’d get started on system tuning and figuring out how to relate what I am doing on the new system to what you can do on yours.  Hopefully this new series will be a help to you in getting the most out of your high-end audio system.

The first thing to understand is key to this whole process – learning your music library or at least the dozen or so pieces of music you are most familiar with.  This may seem really obvious to most of you but I want to assume we haven’t done this before and walk through each step carefully.

To make this process work we’re going to rely on our sound memory.  This is critical to the process and here we’re not so concerned with instruments sounding real, bass being right (or wrong), etc.  What we want to know and get a grip on is how these tracks you’ve chosen work in what you have now.  Let’s call this our baseline reference.

Let’s start with one of my classics that I use routinely, Diana Krall’s CD “From this moment on”.  Track 5 is a particular favorite.  Here’s what I want to know: how does she and her piano sound on what I am listening to?  Does it sound live, studio, natural – are there any “flaws” I hear in the recording, perhaps it’s thin, perhaps it’s fat, etc.  Form an opinion on this disc and this cut assuming the cut itself is perfect and you’re just evaluating that cut as a reviewer might if he were to write a review.

Make mental note.  Take written notes if you have to, but better to really listen and get intimate with the recording.  Now do the same for a few more – using a wide variety of musical types and form an opinion on each.  This process might take you a few days, but it’s important.

Where you want to wind up is a level of intimacy with how this track sounds on your system right now – for better or worse – because you’ll need this info to make forward progress on the next steps.

Paul McGowan – PS Audio, Intl.

Maybe your not playing fair?

Yesterday’s post surely got some of you riled up and perhaps I got a little carried away with my “emotional attachment” comment – no, not perhaps, definitely.  It is very system dependent – and as several of you have correctly pointed out, including my friend Michael Fremer, my turntable system and methodology doesn’t come close to matching that of the digital system.

But some good questions came up and I want to touch on those.  Several of you pointed out to me that the size of my vinyl library is small, relative to that of my CD and high resolution collection.  Thus I have a rather limited selection of vinyl from which to make a proper judgment.  I couldn’t agree more.

My good friend Josh at Music Direct has been helping me acquire a bigger library and kindly sends me releases he thinks I’ll like – many from their Mobile Fidelity label – and to be honest some of these are just stunning.  I just got the Frank Sinatra collection and that’s awesome.

Should any of you have suggestions of what vinyl I should be playing to discover what many of my readers feel – that vinyl is by far the superior musical medium – bring it on.  Nothing has yet convinced me of this but I am more than open to the idea.  I just love hearing new and wonderful music that thrills and excites, regardless of the medium.

But I should tell you that as predicted, the double edged sword nature of a system like the big IRS is that it shows everything connected to it or played on it – for better or for worse.  So sensitive and clear is this system that even the smallest change to the setup can be instantly heard.  It’s shown me a few surprising things: just HOW good the PerfectWave products are when it comes to digital playback – I was nervous that perhaps they might not live up to this level of exposure – but I was pleasantly surprised.  Cable lengths are more critical than ever – the difference between a 2 meter HDMI cable vs. a 1 meter is immediately obvious – the shorter cable winning out handily.

But the biggest surprise of all is still vinyl.  I figured this system was designed on vinyl – this system was optimized for vinyl – and yet vinyl is definitely the weaker medium when compared to high resolution audio.

Suggestions as to how to change my mind are most welcome.


Paul McGowan – PS Audio, Intl.

Vinyl on the big system

I’ve finally gotten the turntable setup going into the new speaker system and have been, as of late, playing a lot of vinyl through it.  The setup I am using is a Clear Audio Master Solution with their carbon fiber arm and a Denon 103D moving coil cartridge set to 100 Ohms and tracking at 2 grams.

I have a variety of phono preamps to play with but I keep coming back to our new NPC as a good choice.  I like what I am hearing but I can’t, in all honesty, say it’s better than high resolution digital played on the system.  I know, there will be all kinds of teeth gnashing over this and perhaps some of it justified; after all, it isn’t the world’s best turntable/arm/cartridge/preamp setup possible.  But it is more than reasonable, I would assume, and yet ……

When I say it’s not better let me explain in better terms.  There’s a certain romantic quality to the vinyl that I appreciate.  The surface noise, ticks and pops help ground the spacial aspects of the presentation in a very comfortable and pleasing way.  Strings are lush, voices palpable and believable, and many aspects of the medium are wonderful.  And comparing tit for tat vinyl’s better on some discs, worse on others.  Let me give you an example.

My prized and pristine vinyl copy of Casino Royale sounds amazing – there’s no doubt of it.  I also have a high resolution copy of the same I can play to compare and contrast.  There’s simply no comparison as the vinyl version is better – the high resolution copy thinner, less body, threadbare by comparison.  My guess is that whoever mastered the high resolution version din’t have the right set of goals in mind or perhaps had a poor master tape copy.

On the other side I also have a Patricia Barber vinyl pressing of Modern Cool and have acquired a high resolution copy of the same (don’t ask me where).  Now the tables are turned.  The vinyl sounds great, full and round, great presence, but when compared to the high resolution copy played through the PWT and PWD combination there’s just no comparison.  The high resolution version clearly demonstrates the restricted dynamics, frequency response of the vinyl – and now, for the first time, I can clearly hear just how superior the high rez copy is.  No one would miss this hearing it on the big system.  No one.

My favorite track so far is from Reference Recordings HRX series.  The Tempest, track 8, where obviously the waves are getting pretty wild.  Mastered directly off the master digital recording at 176kHz/24 bits and played on the PWT Memory Player, the sound is breathtaking beyond words.  It leaves anything I’ve heard on vinyl in the dirt.  Wall to wall imaging – no, actually the sound field goes beyond the walls of the music room – and the depth goes out into the parking lot.  You’re enveloped in the music in a way that is just uncanny and just when you think it can’t get any louder, the dynamics wash over you and you have to just grin.  Imagine a system without any dynamic restrictions whatsoever, finally showing off what’s truly in the music.

Sorry, I don’t mean to squash any cherished emotional ties to vinyl – and please don’t shoot the messenger I am just reporting what I hear – but there’s no question in my mind that on the right recordings with the right equipment, high resolution digital just stomps anything on vinyl.

Paul McGowan – PS Audio, Intl.

Tough decisions

My son Scott loves music; perhaps more than I.  He’s willing to listen even if the recording is awful and is able to turn off the rejection mechanism so ingrained in my head as an Audiophile.  Part of me wishes I was just as able to be that selective – because I’d get a lot more music on my plate than I do now – but then …..

What’s interesting to me is that as a budding Audiophile himself, he fully appreciates the wonder of a great musical performance AND a great sound presented on a proper system – yet he can toggle between the two modes.

For me, if the music is good enough and I object to the recording quality, I simply put it on my portable music system and listen when I go for a morning run.  On the ear buds I can listen to almost any quality of recording and enjoy the music without prejudice because of the recording – but put it on the big system and I reach for the eject button.

“Back in the day” when I got started with high end audio, it was every person’s dream to have a “kick ass” stereo system and a huge collection of records – so much so that many of us had not much else to our names – there was the stereo, the records, perhaps a water bed and a smattering of furniture.  We listened to everything and only criticized the music itself as being worthy of our time or not.

As I got older and my system got better, I started demanding more: good sound AND a good performance.

I am not willing to give up either at this point and so I spend time searching out better equipment and great performances that I haven’t heard.  I am pretty convinced it’s not a bad thing – I wonder how close my experience relates to your own?

Paul McGowan – PS Audio, Intl.

Through the looking glass

As I get more familiar with the new music system a couple of thoughts occur to me about what it is that gets me excited about what I am hearing and experiencing.  I think the magnification and separation of elements within the recording have to stand out above many others.

I am fortunate enough to have a high resolution copy of Dylan’s Don’t Think Twice, taken directly off the master tape.  This was never a great recording, but the music is so good and simple, just Dylan, his harmonica and guitar, that it’s quite a treat to listen.  On the older system there is clearly tape hiss mixed in with the music and you can easily imagine Dylan just sitting in front of a microphone and singing.

On the new system with the IRS, the tape hiss is completely disembodied from the music.  This is kind of eerie but it justs sounds right.  Separate is good.  You are now aware of the microphone’s contribution to the sound and for the first time I can tell there’s something going on in the recording chain – perhaps a touch of reverb or EQ – it’s hard for me to know – but clearly it isn’t just a straight microphone feed into the recording console.  I don’t have any info on this recording other than it was done in Columbia’s Studio A in New York City.  Older pictures show a Neumann U67 (I am guessing) microphone – which I am familiar with – and there seems more going on than I can account for.

The point of this story is simply this: the greater resolution of the loudspeaker system has enabled me for the first time to hear separated sounds, seemingly magnified through a looking glass, and now that I am familiar with this sound I am convinced it is not something specific to the IRS – it is a quality that I believe many systems can achieve once you know what to look for.

More on this soon.

Paul McGowan – PS Audio, Intl.