Are your speakers losing air?


I was reminded of my own advice today.  I was fiddling with something in my HT system and had my head right up to the center channel.  I noticed that sadly, there was a lot more air and ambiance up close to the center speaker than at my listening location. 

I remembered the advice I often give others about room treatment.  If you sit up close to your speakers you can really hear the detail and ambiance they create, and that all the information you lose between there and your normal listening position is due to the room.  That is, your room is lossy. 

In this particular case I resolved the issue by putting a 2'x4' acoustic absorber across the entertainment center, essentially hiding it entirely with the center peeking up above it.  Problem solved, and suddenly movies and dialogues have a lot more acoustic information than they used to. 

This also shows us a couple of other issues.  My center is, by deliberate design, extremely wide dispersion.  I am most likely suffering from this vs. say a horn loaded center like Hsu or Klipsch offer.  That is, a limited dispersion center may not have had these issues.  The other is that my Butcher Block double wide rack is itself a source of interference with the original signal.  This I may fix more permanently with an IR repeater so I can keep the panel in place. 

Anyway, hope this advice helps you in evaluating how to get the most out of your speakers and room.

erik_squires

Showing 4 responses by erik_squires

@deep_333 The concentric drivers are also very interesting ideas here.

The big challenge for a center is you want to have the dispersion of a 3-way speaker, but the height of 1 woofer! It’s a compromise achieved in a variety of ways. Sometimes with very very small midranges and/or very low profile tweeters but the concentric design is also a good fit here.

The negative for concentric is the doppler shift that happens, especially in a smaller concentric. Still, it is undeniably a good possibility for a low-height, 3-way center channel, or even a less ambitious 2-way with a single concentric.

Well @tvad  - I guess you solved it for everyone!!  I mean, yes, listening nearfield solves the problem if you can listen or want to listen nearfield.

 

Otherwise, EQ the missing frequencies by adding a 3dB-6dB boost.

EQ and room treatements have some areas in which they overlap which is in changing the overall tonal balance, but they are not entirely replaceable with each other.  To use a visual metaphor, you can change the color balance with EQ but not detail like you can with room treatments.

As you increase the treble, you also increase the early reflections, so your signal-to-noise remains constant.  By absorbing early reflections you actually improve the signal to noise ratio. 

Several readers replies make me think that they missed the solution here:

Eliminate early reflections

A principle that can be applied to any speaker.

You’d be shocked at how many well known and well respected, center channel speakers have horrible off axis speaker performance, and measurements.

@simonmoon  That's why I built my own.  😁

 

@moonwatcher  I think you touched on several issues aboout how the home center channel is always a compromise.  In m y case while. the off axis performance is excellent, I don;t have floor space to put it in anywhere but on top of the audio rack, and hence the excellent vertical dispersion is a double edged sword.