Speaker Asylum General speaker questions for audio and home theater.

---

[ Follow Ups ] [ Post Followup ] Thread: [ Display  All  Email ] [ Speaker Asylum ]

---

[ Alert Moderator ]

---

Is this difference at 114Hz and 125Hz normal?

Posted by dave789 (A) on July 16, 2016 at 10:04:23

I took a measurement where a pair of speakers (about 38" from each other) is placed on a 48 inch by 28 inch desk surface and a sub-woofer (consumer brand, without high pass filters for the main speakers) is on the right side of the desk. The room has about $500 amount of bass absorption panels (5.5" thickness (by my measurement) GIK brand. One 12"X48" and one 24X48 right behind the desk, one 12X48 and one 24X48 on the opposite wall, a 12X48 at a corner, a 12X48 at another corner.).

Mic was placed at the usual listing head position.

The walls around the left and right speakers are not symmetric. The right side wall is about 42" from the center of the right speaker. About 25" left from the center of the left speaker there is opening: ways to other areas and to downstairs.

I see a nasty dip and peak at 114Hz and 125Hz, respectively,on the left channel. I moved the left speaker around within the owner's practicality limit, but could not eliminate such dip and peak. For example, moving the left speaker up made the dip and peak nastier. Is the dip and peak something audio maniacs usually accept, or is it worth trying harder to remove it?

I tried wide-overlaping the subwoofer with the speakers on the desk by making the high cut frequency for the subwoofer higher, but observed new deep dip in the overlap. It was hard to achieve shallow dip in all three cases: L, R, L+R.

One possibility is to change the system to a subwoofer and satellite system with a rather high crossover point (about 150Hz): Cambridge Audio Minx or Bose AM 5. I put the left speaker on the left side of the desk where Bose AM 5 bass module's port would be located, and could almost eliminate the dip and peak. However, I have no idea whether the new high-crossovered subwoofer and satellite system will produce new nasty dip and peak in 100Hz - 200Hz.

The frequency-amplitude graphs are 1/48 oct smoothed.

Edits: 07/16/16 07/16/16

This post is made possible by the generous support of people like you and our sponsors:

VH Audio

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---