A Brief Guide to Audio for the Skeptical Consumer, Part II

07Feb15

…Or What I Wish I’d Known about What Does Make a Difference in Home Audio

A year ago I wrote a blog post detailing what I wish I’d understood about audio when first becoming obsessed with this stuff. This article has been shared vastly more times than anything else I’ve written, and I admit it gives me satisfaction to see that on certain days there has been tens of thousands of views. On Facebook and Reddit there has been page after page of vitriolic debate concerning my article, which I generally find amusing to read.

When digesting some of the online discussion of my blog, there is one criticism that does sting a little: The accusation that people like me think that nothing in audio makes a difference. They suppose that since we generally don’t believe in sonic differences in speaker wire or modern amplifiers then we must just think everything sounds the same. They presume this is because we can’t hear sufficiently or we don’t really love music or we haven’t yet spent X dollars on our stereo systems.

I’ve personally found the exact opposite to be true, and when I started following the advice of legitimate audio experts, I found there are many upgrades or tweaks that have brought about massive sonic improvements in my own system. What’s more, these upgrades don’t involve purchasing expensive boutique speakers or retro tube amps, and without exception they are affordable to most any sufficiently motivated working-class person. I am forever grateful to these individuals for setting me on the right path, as there are few things in my life that provide me with more pleasure than listening to music in my own home. The 21st century is an amazing time to be a music lover, and as with phones or vacuum cleaners or any other electronic product, audio gear is getting cheaper and more effective all the time. I can think of few “come to Jesus” moments more significant in my life than first dialing in a subwoofer or putting up acoustic panels.

When I was wasting my family’s money on upgrading to “audiophile” interconnects and amplifiers, some part of me knew what I was doing was pointless. But then I thought, how could these editors of Stereophile be so wrong about everything? These guys are the experts, right? And Miles is sounding pretty effing good tonight, maybe bi-wiring does make a difference…. If I hadn’t found another path I can only imagine that I’d have either lost interest in audio, or worse, bought something on the Class A list of Stereophile recommended components.

The following list is roughly in the order of what I’ve personally found makes the most difference in sound quality. Though I believe that everything on this list is a rough reflection of best practices promoted by legitimate experts, as they say on audio discussion forums, YMMV:

1. A subwoofer is the cornerstone of a modern stereo system. Compared to even top-of-the-line full range speakers, decent subwoofers can reproduce the lowest frequencies found in both music and film more accurately, louder with less distortion, and for a whole lot less money. Since stereo imaging is not important for the lowest frequencies, the subwoofer can be placed where the bass is most accurate given the acoustics of a particular room. And because a subwoofer relieves the mains from having to reproduce the most difficult lowest frequencies, even the midrange can improve when a subwoofer is used. 

It would not be unreasonable to spend 50% of more of one’s audio budget on subwoofers. These lowest frequencies might seem to be a relatively small part of music, but they are the most difficult to reproduce properly, and a big subwoofer with a powerful amplifier is the right tool for the job. For most users best results are achieved using a receiver with bass management features. Proper calibration is essential. 

frequencies

2. Acoustic treatments can vastly improve sound quality. While this area can quickly become quite complicated (and controversial), for most users these treatments take the form of absorption panels. To improve stereo imaging these panels are placed at reflection points on the walls and ceiling between listener and speakers. Somewhat more difficult is to significantly improve bass response with bass traps, which are typically larger absorption panels placed in corners.

3. Speaker positioning should be a prime consideration for all critical listeners. While few enthusiasts are lucky enough to have dedicated listening rooms of ideal dimensions, substantial improvement to sound quality can be achieved by placing speakers as closely as possible to what is recommended by experts. 

correct-speaker-placement

4. All speakers possess their own unique sonic characteristics, which interact with a room to define what a listener hears from a given recording. A few of the issues to consider when deciding which speaker to buy:

  • Science indicates that most listeners prefer on and off accuracy, so look for these frequency response measurements. (Watch Dr. Floyd Toole’s essential talk about sound reproduction.)
  • In-room listening is highly desirable when evaluating a given loudspeaker. 
  • In-room listening may in fact be easier with internet direct manufacturers, as many provide excellent (often free) return policies. These ID manufacturers may provide a greater value compared to what is available at brick and mortar stores at large mark ups.  
  • Another valid perspective is that some larger companies may offer a better value since they have larger engineering budgets and can hit lower prices due to their products being mass produced using cheap labor.
  • Never, ever assume that because a speaker is more expensive that there is a corresponding increase in sound quality. Most speakers marketed as audiophile luxury items may look prettier, but oftentimes this is all one is paying for. Many are even quantifiably less accurate that cheaper speakers.
  • Most users should consider a bookshelf + subwoofer over so-called full-range loudspeakers. 
  • There are sound quality advantages to self-powered monitor speakers, though many users will find these less convenient since each speaker needs a power supply and to be turned on individually.  

LSR305-large

5. It should never be assumed that audiophile amplifiers, whether integrated or monoblock, improve sound quality over modern AVRs available for a fraction of the price. Conversely, these AVRs can actually improve sound quality, not only because they are the correct tool for integrating a subwoofer but because the digital room correction software can create improvements in less-than-perfect rooms (i.e. all non-dedicated listening rooms). This software uses a measurement microphone to gain information about a room/speaker response at multiple locations. While this digital signal processing should never be seen as substitute for room treatments, improvement to sound quality can nevertheless be had (if more on the level of fine tuning). These programs are becoming more sophisticated and affordable with each passing year.

AVR4308LARGEback

6. Room EQ Wizard is a free program used with a < $100 calibration microphone connected via USB cable to a laptop. The enthusiast (or engineer) can then create graphs of the frequency response and bass decay amongst other sophisticated measurements. These measurements are highly useful for determining subwoofer placement as well as the effectiveness of acoustic panels.

after treatment

7. Multiple subwoofers can be used to achieve flatter frequency response (more accuracy), especially across multiple listening positions. Two subwoofers will typically offer a substantial improvement over one in most spaces, but going beyond four is generally unnecessary. 

PB-2000Zoom

8. Dynamic equalization is a feature found on most modern receivers that adjusts volume of higher and lower frequencies to account for how we perceive sound. It functions somewhat like a more sophisticated “loudness” button found on older receivers. As volume is turned down from the reference volume film/music is mixed at (usually quite loud), the highest and lowest frequencies are dynamically turned up to account for the way our ears/brains perceive sound.

SEE ALSO: A Brief Guide to Audio for the Skeptical Consumer: Part I 

Advertisements


6 Responses to “A Brief Guide to Audio for the Skeptical Consumer, Part II”

  1. http://www.nousaine.com is also a good source for subwoofer information. Tom really, really, really liked subs.

    And while for the most part amps sound the same — given the usual caveats about operating within their limits — a high power amp is a revelation on dynamic material. I ran extemely high power amps (two bridged Dynaco Stereo 400’s) for a long time and listening to pretty much anything, but especially classical music, was an amazing experience. When you have that much power available peaks are never compressed and the sound just opens up. Too bad putting together an HT system with that much power costs tens of thousands of dollars.

    However you can get very good results with modern speakers and a decent AVR of 125 W/pc or so, it is just that these days everything is rated in Japanese watts instead of American watts (because back in the days when there were affordable American made amps, their power ratings were always silly conservative and Japanese receivers pushed the limits of the FTC rating.)

    • Funny, I was just looking at the Nousaine site today. The articles about subwoofers are from the ’90s and maybe don’t totally reflect current thinking from what I understand, but I really enjoyed his articles on listener bias. From “Can You Trust Your Ears?”:

      “No one has ever produced a scientifically-controlled listening test showing that well designed amplifiers (flat response, no clipping) […] have the slightest effect on the sound being produced.”

      http://www.nousaine.com/pdfs/Can%20You%20Trust%20Your%20Ears.pdf

      Of course I don’t see myself spending tens of thousands of dollars to test out your experience for myself any time soon. Maybe someday.

      Here is a discussion on AVSforum I saw recently on the “more power = more control” issue that I think you’re getting at. I guess it’s pretty obvious which side I find most credible in this debate:

      http://www.avsforum.com/forum/91-audio-theory-setup-chat/1823514-current-equals-control.html

      Thank for weighing in!

      • These days truly high power amps do cost bucks. My Dynaco’s only cost $200 each back in ’83 or so, even then that was not that bad. Even now you can get one for not much money:

        http://www.ebay.com/itm/Dynaco-400-With-Blue-Factory-Meters-One-Of-The-Most-Classic-Amps-Of-All-Time-/121475060653?pt=LH_DefaultDomain_0&hash=item1c487a53ad

        If you want to have fun…

      • It’s not really more control. A couple of the early posts in that thread hit the nail on the head: headroom is what it is all about. Headroom has nothing to do with “control” or PRaT or any of the other BS thrown around in that thread by F.Cook and like minded people… Headroom is about how much power an amp can deliver and when you need to handle 10 to 20db peaks, you need a lot of headroom with modern, inefficient, speakers (old Klipschorns are about 106db/1w/1m, most speakers today are about 20db less efficient).

      • I’m no expert, but I have researched the heck out of this. Sure, headroom is important, but I don’t believe that those in the forum mentioning this issue would say that the sound “opens up” or is a “revelation” when one moves to an amplifier with more power. The conclusion that I’ve reached is that unused power is unused power. Period. As Nousaine says above (and is almost universally acknowledged amongst credible experts as far as I can tell) there’s never been a level-matched double blind test that suggests otherwise for modern amplifiers not driven to clipping. If moving to a higher power amplifier is truly a “revelation,” don’t you think it would be detectable in such a test?

        Personally, I strongly suspect that a common 100 WPC AVR (as I own) is more than enough to take me to any SPL I would ever want to go to even on my wildest night. I think it’s far more common these days to have more wattage than one would ever need rather than the opposite.

  2. 6 Max

    Cool post. I am an old dog who learned about audio in the 1970s as a teenager. I laughed when you mentioned “Stereophile”. I remember that magazine. I also remember thinking, “These guys are nuts.”

    Good speaker placement, good room acoustics, good speakers, good input source material, to me, make the most difference. Lots of headroom from a big power amp does matter when you play music a little on the louder side.

    To this day, I still have the same gear I had in 1980. As the eras of equipment came and went, the prices climbed and climbed, and the audio shops vanished, and considering I am handy enough to replace simple components, I just see no reason to swap it out.

    And yes, my power amp is indeed one of those beautiful old Dynaco Stereo 400’s with the blue meters. When I traded up from the ST80 to the 400, the increased clarity was unmistakable.

    Except for cleaning the controls, tightening internal connections, and checking the bias current, I haven’t done a thing to it. I know all about suggested upgrades, the old caps, etc. But haven’t had to do it. The preamp is an old Dynaco PAT-4, and they drive a pair of AR-5’s — speakers that I think are often-overlooked unsung stars. For the relatively modest size of those cabinets, they pack the most beautiful sound.

    Just keep them away from the wall or corner and the bass smooths right out (remember… SPEAKER PLACEMENT AND ROOM ACOUSTICS!)


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: