What creates good imaging?

[3db]

I am on the hunt for new speakers. I am currently running some old MB Quart QLC-404s. I picked these speakers up a long time ago for pretty cheap when I was much poorer. These speakers have served me well for about 8 years, but a substantial update is long overdue.

I have been auditioning speakers locally. Today I listened to some GoldneEar Aon 2s and 3s. They both sounded way better than my old MB Quarts, but the number one thing that jumped out at me was how well they imaged.

When I was listening to the Aons a trumpet sounded like it was dead center of the soundstage. On my MB Quarts its just a giant wall of sound in which its hard to pinpoint where things are in the soundstage. Which leads me to my question.

What speaker qualities create good imaging?

-- jaydillyo

I'm wondering if the Quarts were wired out of phase with one another.

 

[JerryLove]

Maybe I'm over simplifying this a little but wire one of the speakers out of phase and see if you can correct it with acoustic treatments.

The danger would be actual phase cancellation. Other than that: I don't think you'd notice.

For example: subs tend to work just fine with a 180-degree switch. Go change the phase on your sub phase by 5-degrees and see if the sound-stage moves.

 

[3db]

The danger would be actual phase cancellation. Other than that: I don't think you'd notice.

For example: subs tend to work just fine with a 180-degree switch. Go change the phase on your sub phase by 5-degrees and see if the sound-stage moves.

Try it Jerry. You'll be surprised how wiring one speaker 180 degrees out of phase will affect the soundstage. I noticed it right away before using the room correction software on my AVR when having wired up my system after a home move. Your example of bass is not a good example as bass is omni directional to begin with in stark contrast to the mids and highs which are far more directional.

 

[JerryLove]

Try it Jerry. You'll be surprised how wiring one speaker 180 degrees out of phase will affect the soundstage.

I won't. I've done it before. There is phase cancellation at wavelengths long enough to do so. Exactly like I said in my previous post.

Your example of bass is not a good example as bass is omni directional to begin with in stark contrast to the mids and highs which are far more directional.

Try it. Put two subs right next to each other and 180-degrees out of phase. You'll be surprised how it affects sound.

 

[3db]

I won't. I've done it before. There is phase cancellation at wavelengths long enough to do so. Exactly like I said in my previous post.


Try it. Put two subs right next to each other and 180-degrees out of phase. You'll be surprised how it affects sound.

I was able to tell almost instantly when vocals started that my speakers were wired out of phase. Instead of it being centered, the vocals were smeared across the soundstage.

 

[Dr. Parthipan]

I was able to tell almost instantly when vocals started that my speakers were wired out of phase. Instead of it being centered, the vocals were smeared across the soundstage.

what are you both arguing about? wiring the left speaker out of phase with the right?

 

[JerryLove]

Any two drivers.

But yes, if left and right are out-of-phase (if their timing is different) I would completely expect that to move the sound-stage at medium frequencies. (HF I'm not so sure and LF I'd expect actual cancellation).

 

[Irvrobinson]

I'm not sure exactly what qualities create good imaging, but I continue to be amazed by the imaging of the Revel Salon2. It is eerie. For example, my wife and I were just listening to Peter Schickele's PDQ Bach 1712 Overture CD from Telarc. On track 5, Schickele is supposedly standing outside somewhere in LA, and a jet flies overhead. Now when I say a jet flies overhead I'm not kidding, it sounds like the damned jet is really flying overhead. It is so weird that an audio system can do that with only two speakers that my wife actually doesn't believe it. She thinks the jet only appears to come from overhead because it sounds realistic and that's where your mind expects it to come from. It is by far the weirdest imaging effect I've heard yet from an unassisted stereo system.

[By the way, IMHO if you don't find Schickele's arrangements to be incredibly humorous and quite brilliant your taste is truly unsophisticated, and is in dire need of improvement.]

 

[monkish54]

I'm not sure exactly what qualities create good imaging

Reflections & phase create imaging--just as they do in everyday life.

Phantom Images at the Side
A phantom front center image can be generated by feeding identical in-phase signals to speakers at the front left and front right of a forward facing listener. The surround sound crowd would be ecstatic if they could produce as good a phantom image, to the side, in the same simple way, by feeding identical in-phase signals just to a right front and a right rear speaker pair. Unfortunately, phantom images cannot be panned between side speakers the way they can between front speakers without involving the other ear through speakers operating under Ambisonic or other interaural coding scheme or by using dynamic, individualized pinna and head equalization. The reason realistic phantom side images are difficult to generate is that we are largely dealing with a one-eared hearing situation. Let us assume that for a right side sound only negligible sound reaches the remote left ear. We already know that the only directional sensing mechanism a one-eared person has for higher frequency sound is the pinna convolution mechanism. Thus if a sound comes from a speaker at 45 degrees to the front, the pinna will locate it there. If, at the same time, a similar sound is coming from 45 degrees to the rear, one either hears two discrete sound sources or one speaker predominates and the image hops backward and forward between them. Of course, some sound does leak around the head to the other ear and depending on room reflections, this affects every individual differently and unpredictably.

http://www.stereotimes.com/comm0499.shtml

but I continue to be amazed by the imaging of the Revel Salon2.

That's because the company who designed the Revel Salon 2 hired a guy who LITERALLY wrote the book (he did so after leaving the company) on a speaker's ability to image and sound spacious.

She thinks the jet only appears to come from overhead because it sounds realistic and that's where your mind expects it to come from. It is by far the weirdest imaging effect I've heard yet from an unassisted stereo system.

Other effects can be heard overhead using a stereo pair of loudspeakers. Try some tests online!

http://www.audiocheck.net/audiotests_ledr.php

 

[3db]

Any two drivers.

But yes, if left and right are out-of-phase (if their timing is different) I would completely expect that to move the sound-stage at medium frequencies. (HF I'm not so sure and LF I'd expect actual cancellation).

Based on my observation, I would say imaging has a great deal to do with the speakers themselves and room acoustics will either detract or augment a speakers imaging capabilities. It's not sole the property of room acoustics that affect imaging.

 

[Refuge]

Imaging starts with at least 2 good quality speakers closely matched in frequency response, timber, and volume. "STEREOPHONICS" is the key to imaging.
Good quality speakers start with matched drivers, well designed and integrated crossovers, and a speaker-driver to baffle relationship that has "imaging" as a design factor.
Low frequencies define the "acoustical size" of the original sound field as they reproduce the apparent image within the listening environment.
Room shape affects reproduction of the original sounds. Every room has modes.
High frequencies define the "acoustical quality and position" of the apparent sound sources within the original sound field.
~ONLY well recorded material will get anywhere near reproducing image, depth, and sound stage. Audio that has been haphazardly compressed to obtain a smaller file size
will have a hard time reproducing believable sound sound stage with imaging.
~Newer electronics are capable of shaping and changing image using the different electronic formats built into any given receiver, amp, or pre-amp.
~Your own listening environment can be changed to augment or diminish the amount of image and sound stage.
There is no "set" amount of reflection and/or absorption levels. Your own preferences prevail here.
Generally most homes and apartments even with full carpet are too reflective and will benefit from extra absorptive materials like drapes and curtains.
~Speaker separation is important in maximizing image and sound stage. Height above the floor has an affect on imaging. Toe-in and out can affect image.
Speaker distance from back and side wall affects image and sound stage. Listener distance from the speakers is important.
~Today's electronics, especially receivers, have all sorts of sound shaping and environment changing capabilities built in. Most have a form of MCACC or Audyysey
which, with their built-in mic and measurement system, will make your listening environment and speaker system much more useable and phonically-neutral.
Home Theater isn't easy if your looking to gain the best performance from your equipment. Experimentation and your own ears will yield some amazing results.
~"Your own ears" brings up a good point, how good are your own ears? Remember, as you get older you lose ability to hear high frequency sounds. It's inescapable.
There are a bunch of hearing tests on the internet that you can perform. Use a good set of ear buds and test your own hearing.
Are you over 30? I'll bet you can't hear above 12,000Hz. If you're younger, protect your hearing.
Surprisingly sounds we normally consider "safe" for our ears like wind noise from an open car window at 60MPH can damage hearing over time.
Or even live Rock Concerts that last only a couple hours but experiencing 105dbs will quickly produce damage. Remember, once your hearing is gone, it's gone.

 

[jaydillyo]

I haven't checked in here in a while, but thanks for all of the responses.

FYI, I am 34 and can still hear up to 17 kHz. I do my best to protect my hearing. A few years ago I had a really annoying hum in my right ear that would come and go. It made me really paranoid about my hearing. The good news is that I haven't had that problem in a long time. I can't tell you why. Used to drive me nuts when I was trying to fall asleep.

I'm satisfied with the imaging the Aon 3s are producing. It makes music a lot more engaging.

I don't have any room treatments yet. After I repaint the room I'll consider adding some. They just need to look good.x

-- jaydillyo

 

[ifsixwasnin9]

Imaging Definition from PC Magazine Encyclopedia

Definition of: imaging
The illusion of a live performance in audio playback. Microphone placement during recording, post-recording mixing in the studio and the performance of the speakers when listening all contribute to the quality of the imaging. Geared to the type of venue such as a concert hall or nightclub, surround sound processing in the audio equipment creates or enhances effects that attempt to make imaging more realistic.

Speaker Imaging
From the playback side, imaging quality is derived mostly from the speakers. The stiffness and mass of the speaker cone, along with the materials used to suspend the cone in its frame, are the primary criteria that affect the speaker's capability of reproducing sound accurately, and thus the imaging.

1) General question I have: (If speakers are wired in-phase) and you walk around a room phases are constantly changing due to reflections, right?
2) Dispersion is a major factor in reflection and therefore major factor of phase?

I believe what creates good imaging is the speakers ability to produce a good off axis response, in other words, it's ability to produce soundwaves well beyond it's rated range.

I notice my JBL L110s sound much better (clarity and balance) on-axis. So what's happening off-axis? Efficiency and/or Sensitivity becomes poorer off-axis?