I saw a brief mention of cross firing speakers in the Trinnov HT guide - aiming right front a little to left and aiming left front a little right to widen the listening position. I was wondering if anyone uses this in their stereo or home theater space?
-
WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
Cross firing speakers
- Thread starter Jbrunwa
- Start date
I have done this. I find it accentuates center image effects at the expense of the simulated Soundstage.
I start positioning with a pencil taped on top of each speaker, along the center line. Sighting down the pencil, point that at the center of my chair and give a listen to something simple and familiar.
I gradually point the speakers until the most neutral tonal balance is found.
This is largely superseded by measurement microphones.
In my last traditional loudspeaker build, I tried the cross fired alignment and found the image stability startling (with acceptable treble response) but some more complex recordings - presumably multiple microphones were anomalous, particularly in midbass range.
I start positioning with a pencil taped on top of each speaker, along the center line. Sighting down the pencil, point that at the center of my chair and give a listen to something simple and familiar.
I gradually point the speakers until the most neutral tonal balance is found.
This is largely superseded by measurement microphones.
In my last traditional loudspeaker build, I tried the cross fired alignment and found the image stability startling (with acceptable treble response) but some more complex recordings - presumably multiple microphones were anomalous, particularly in midbass range.
I use this technique. My loudspeakers directivity is a bit narrower so I get anywhere from direct axis response to about 30 degrees off axis depending on where I sit. The resulting balance between the boxes seems to even out better this way. The closer box will always be off axis and doesn't overwhelm the other box that's on axis. Your listening distance will determine the toe in. That and how much seating area you're trying to cover.
Hipper
Addicted to Fun and Learning
I found the biggest effect on getting a strong phantom image was stopping side wall reflections.
Just on toe in, it surely very much depends on your speaker directivity, as puppet suggests. I have ribbon mids and highs on my speakers and found the best was to aim for the centre of the chair. The speaker manufacturer I think recommended the centre of the rear wall.
Just on toe in, it surely very much depends on your speaker directivity, as puppet suggests. I have ribbon mids and highs on my speakers and found the best was to aim for the centre of the chair. The speaker manufacturer I think recommended the centre of the rear wall.
audiofooled
Addicted to Fun and Learning
- Joined
- Apr 1, 2021
- Messages
- 533
- Likes
- 594
I do it for mid bass. I like it strong and focused. Once dialed in, most of the time it would also benefit sound stage and imaging.
digitalfrost
Major Contributor
See http://www.libinst.com/PublicArticles/Setup of WG Speakers.pdf
I don't do it but I listen in the nearfield. In a HT situation, I surely would. Seems to be the best way to get even response across all seats on the couch.
I don't do it but I listen in the nearfield. In a HT situation, I surely would. Seems to be the best way to get even response across all seats on the couch.
ernestcarl
Major Contributor
This can work quite well, but it also largely depends on your speaker's directivity control and room acoustics.
I advise using wide Q (rather than narrow or sharp) corrections and minimizing the amount of (positive or negative) gain applied -- after all, you are equalizing for a much larger seating area here instead of just the usual primary listening seat.
Interestingly, SPL attenuation of the farthest speaker away from the left and right corners of my couch isn't all that much.
Here's some pictures of my own listening room situation:
Speakers are angled so as to face corners of the couch rather than the center seat -- this also minimizes/avoids direct side-wall reflections.
And so now, for the umpteenth time, I've made changes to the equalization of my speakers (Presonus Sceptre S8) primarily using moving mic and frequency dependent windowing techniques -- but also some extreme nearfield quasi-anechoic stuff in the highest frequencies:
The summed L+R bass response from all drivers should perceptually sound more even throughout wider couch when done with a milder EQ correction:
Here are some REW MDAT files to review if curious:
COUCH - ALL SEATS - sine swept FDW 10 + psy smooth.mdat
COUCH - ALL SEATS - MMM.mdat
I advise using wide Q (rather than narrow or sharp) corrections and minimizing the amount of (positive or negative) gain applied -- after all, you are equalizing for a much larger seating area here instead of just the usual primary listening seat.
Interestingly, SPL attenuation of the farthest speaker away from the left and right corners of my couch isn't all that much.
Here's some pictures of my own listening room situation:
Speakers are angled so as to face corners of the couch rather than the center seat -- this also minimizes/avoids direct side-wall reflections.
And so now, for the umpteenth time, I've made changes to the equalization of my speakers (Presonus Sceptre S8) primarily using moving mic and frequency dependent windowing techniques -- but also some extreme nearfield quasi-anechoic stuff in the highest frequencies:
The summed L+R bass response from all drivers should perceptually sound more even throughout wider couch when done with a milder EQ correction:
Here are some REW MDAT files to review if curious:
COUCH - ALL SEATS - sine swept FDW 10 + psy smooth.mdat
COUCH - ALL SEATS - MMM.mdat
Last edited:
- Thread Starter
- #8
Thanks for sharing the tutorial!
- Thread Starter
- #9
Thanks for sharing the incredibly detailed information about your approach, process and measurements. This gives me good ideas to start experimenting. And using wide Q makes sense, another thing I hadn’t considered.
Having the loudspeaker axes cross in front of a central listener was first advocated by Hugh Brittain of the GEC Hirst Laboratory in the very early days of stereo, so some time in the 1950s. It was intended to widen the listening area for listeners off-axis.
S
S
ernestcarl
Major Contributor
After some more time spent listening, I've come to the conclusion that my conservative ultra-minimalist speaker EQ may have been a tad too sparing... seems I needed to cut down more the excess brightness (directivity curves bunches quite a bit) around 6-11 kHz:
*slight peak difference at 10 kHz and quicker declining slope seen of my nearfield quasi-anechoic measurements are due to the difference in mic calibration — but not too important — as the overall trend of the curves look clear enough.
Measured this some time ago but still very useful as a reference when re-equalizing speakers:
I'm still experimenting in trying to EQ the sub (with the absolute fewest PEQs possible) for my speakers -- as it turns out, my very nearfield measurements look nothing like what is measured in the listening seat! When it comes to the bass measured, the room truly dominates the response no matter how flat the frequency response is anechoically...
*Yikes! Talk about room gain!
Well, at least the dips aren't that bad compared to some others I've seen.
*slight peak difference at 10 kHz and quicker declining slope seen of my nearfield quasi-anechoic measurements are due to the difference in mic calibration — but not too important — as the overall trend of the curves look clear enough.
Measured this some time ago but still very useful as a reference when re-equalizing speakers:
I'm still experimenting in trying to EQ the sub (with the absolute fewest PEQs possible) for my speakers -- as it turns out, my very nearfield measurements look nothing like what is measured in the listening seat! When it comes to the bass measured, the room truly dominates the response no matter how flat the frequency response is anechoically...
*Yikes! Talk about room gain!
Well, at least the dips aren't that bad compared to some others I've seen.
Last edited:
Yes and ime it works well. I deliberately design with cross-firing in mind, for a variety of reasons.
I used to manufacture speakers with 45 degrees of toe-in already built into them, like this, such that the speaker axes naturally criss-cross in front of the listening position:
The horn is a constant-directivity type whose radiation pattern is 90 degrees in the horizontal plane, crossed over to a 12" woofer where their radiation patterns match (about 1.2 kHz). Here's a pair of them in action in a home theater system:
And finally here's a thread started by the person who took that photo, who sold his center channel speaker because he no longer needed it:
https://www.audiocircle.com/index.php?topic=100196.msg1010455#msg1010455
He uses the speakers in "phantom center mode" for home theater, and appropriately the screenshot is from Phantom of the Opera.
Imo the radiation pattern control was a key piece of the puzzle as far as making the center channel speaker unnecessary for off-centerline listeners. Credit to Earl Geddes for teaching me his technique. For people with a hearing imbalance (one ear hears significantly better than the other) imo a center channel speaker would still be beneficial.
I no longer make speakers with this configuration because it was just too weird to be successful in the marketplace, but I still recommend the 45 degrees of toe-in with my designs.
Last edited:
- Joined
- Jun 5, 2020
- Messages
- 4,799
- Likes
- 3,744
I have done it and it does improve the center image for my other seats.
However, the soundstage gets kind of weird for my seat, so I haven't been able to successfully leave it that way. I want it to work so I can continue to skip the center speaker.
However, the soundstage gets kind of weird for my seat, so I haven't been able to successfully leave it that way. I want it to work so I can continue to skip the center speaker.
Freeway
Senior Member
- Joined
- Apr 10, 2021
- Messages
- 325
- Likes
- 379
It works really well. Less than 45 degrees off the wall. Bingo.
Desktop very nearfield situation. Axis crosses the front edge of the desk a good 1'6" in front of my nose.
You didn't perhaps work for NHT when they first came on the scene?
Ha! Nope, if I recall correctly those were designed by the great Ken Kantor, who also designed the brilliant (but commercially unsuccessful) Acoustic Research MGC-1 "Magic" speaker.
It seems to me that the NHT's built-in toe-in is a lot less than 45 degrees, and puts the listener closer to on-axis than my Geddes-inspired criss-crossing geometry does.
That's too bad Duke. I'd think that WAF would be quite good.
I thought so too, and the first model I made with the built-in toe-in defied the very laws of physics: I had shoehorned a 12-inch diameter woofer into the front baffle of an 11-inch wide cabinet. The audio world was not impressed.
