Hey Guys,
The confusion herein is that TLS is using in-room response curves pulled from our forum, these measurements are not anechoic, they include 1st, 2nd and 3rd reflections. All of those dips and peaks that he is basing his assumptions on are room effects. In addition, he is also pulling quotes from (I don't even know where) that aren't even associated with the measurements that he posted. More specifically, the comment regarding Sierra-1 port tube tuning. The Sierra-1 is tuned to 40Hz, as clearly evidenced in the impedance curve graph he posted.
While I think this is a great discussion regarding the pros and cons of Audyssey, and like others -- I turn it off for music listening, it is really not cool to pull measurements off our site without quoting the text associated with those measurements.
Here is the direct link to the post on or forum where those measurements were pulled:
http://forum.ascendacoustics.com/showthread.php?4392-Information-about-new-Sierra-1-and-Towers&p=35500#post35500
For those of you who aren't members of our forum, (I am not sure if you will be able to see the associated text) -- here is the text:
Below are some in-room measurements of the final version of the NrT compared to the standard Sierra-1. Ignore the peak at 100Hz and the dip at 200Hz as these are caused by floor bounce (reflections). The measurements were taken with the speakers positioned in the middle of the room with about 3 feet clearance from the wall behind them. Our listening room is ~ 14.5 feet wide and 20 feet long. Another important item to point out, since a few non-Sierra owners have expressed their doubts, the in-room bass response in this large room with no corner loading is exactly -3dB at 36Hz, even better than our posted specifications and that is with the speakers located away from walls and corners.
Measurement below taken with a microphone distance at 60 inches. Sierra-1 NrT is yellow, standard is green. Notice how the NrT high-frequency response flattens out while the Sierra-1 starts to roll-off.
Here is the response with the microphone distance at 80 inches. Notice that the further the distance away, the flatter the high-frequency response becomes.
If you go to the post, you can see the 2nd measurement with the mic pulled back to 80 inches and see how the HF response starts to droop downwards a bit, proving one of TLS's comments about the relationship between listening distance and direct/indirect sound and how it affects the HF response.
Anyway, I am not quite sure why there is an attempt at starting up some controversy, and I can understand TLS Guy's comments towards our Sierra-1 if he did not read the associated info about the measurements he was evaluating (anechoic Sierra-1 measurements are readily available on our website) So I hope this quells the matter and the discussion regarding Audyssey continues onward...
And BTW, my apologies to the DIY'ers... (I built my first DIY speaker back in 1985, using a radioshack midrange, a pioneer woofer, and a tweeter designed for cars -- still have these speakers somewhere) Comments were sent to me, and I responded somewhat angrily towards them as important additional info was not shared with me. Big thanks to the forum member here that did provide me with not just bits and pieces of conversations...
