Finding your Room’s Anchor Location.
Where should your two-channel stereo listening chair be? Where it looks the best or where it sounds the best? In this feature I present how to find your anchor location, the spot where bass is smoothest and where your chair should be. I show how small changes in listening location impact the frequency response and how that can impact your listening experience.
The least experienced audiophile will recognize that sitting back and moving your head forward in the chair changes the sound. Yes, stereo can be that finicky, people love it or hate it. Positioning of loudspeakers will have a dramatic impact and there are several elements to perfection:
Distance the speakers are away from the front wall.
Distance the speakers are away from the side walls.
Speaker toe in, will impact spaciousness and timbre, changing the ratio of direct to reflected sounds.
But finding where you should sit should be step 1.
For my measurements I placed one loudspeaker along the centerline of the room for greatest bass activation, moving the UMIK-1 microphone away from the speaker along the centerline of the room (ideally where your chair will be placed).
Locate the microphone at listening height, pointed forward.
Looking at the nearfield response, one to four feet away from the speakers, the response is fairly uniform with a dip at 69 Hz. The closer to the speaker the more gain at 95 Hz.
From four to six and a half feet away we can see a fair amount of change in the 95-100 Hz dip and the 150-200 Hz region.
From six to nine feet away we can see more change. The 69 dip has moved up to 75 Hz with varying levels of smoothness, and several peaks and dips above 100 Hz.
Listening at 6 feet away, which seems like a natural listening location, most definitely is not the smoothest place to be.
Seven foot six inches appears to be the flattest response, what happens if we move just three more inches back or forward?
The graph below shows all the measurements from nearfield to ten feet away, highlighting seven foot six inches, which is where I will locate the listening chair as the anchor spot. Is it perfect? With 18 dB of variability (31 to 49 dB SPL min to max), no, but my stereo still sounds great!
Moving your head back and forth in the listening position can have a big impact to what you hear, as you see in the FRFs.
The OG & best looking chair location, 6’ 6”, not quite the perfect spot, not the anchor location.
Special acknowledgements
to Stephen Dull at Westside Music & Cinema for his insights and sharing on Room Play, taking the mystery out of room setup. To his collaboration with Jim Smith “Get Better Sound”.
If you would like specialized help on room setup, don’t hesitate to reach out to AAE or Westside.
