What affects front to back depth in room/ system?

I've been moving speakers around for a while now trying to maximize their placement for a happy balance of soundstage width, focus of center image, vocal height, instrument placements, etc. I want to get the speaker placement settled before acoustically treating the room. The room is 15x20 with 8' ceilings. Speakers are setup along the 20' wall. I'm pretty happy with most aspects of the sound, but what I can't seem to figure out is how to improve the depth. Honestly, I'm not sure if what I'm after is attainable to begin with. Is it possible to have depth that reaches the listening position in a 2.2 channel sound system? The depth behind the speakers is great, just not much in front of them- unless it's one of those songs that has a part where it has that inverted phase trick. Then it washes over me. I want that all the time. Any feedback and advice is appreciated. 


This has a lot to do with equipment quality and system setup


You need high resolution gear and a system setup with good cabling power vibration conditioner vibration reduction you haveto maximize what the system can show you and if it is in the recording you should get it

Acoustic treatment in dimension of concern.  Diffusion behind speakers and listeners, ceiling absorbers between speaker and listener

A primary factor is how much space behind the speakers.

My current setup, wall behind, I get great imaging EXCEPT limited Depth


Prior Location, Long Space, Speakers 2/3’s out facing Living Area One End, Very Wide Archway Open to Dining Area Behind Speakers: MORE DEPTH.

However, the reverse existed regarding rear wall reflection timing..

Prior: Sofa against rear wall, quick rear wall reflections

Current: Open space Behind Listening Position, diminished volume of and increased time delay of rear reflections, improves precision of imaging.

And: Rear PORTS: Closed here, Open Prior (a bit of extended bass out of the 15" woofers) too close to rear wall now.

I was young, thinking too much, had Electrovoice Engineers help me with port design, never needed, waste of time.

My friend has my old JSE Model II’s, he loved them here when younger. He lives in a Firehouse he bought, they have PLENTY of space behind and to the side, he updated the crossovers, changed the tweeters from those nice but easily blown Dynaudio D21’s.

HOWEVER, like my prior location, his sofa is against the wall behind. I keep telling him, treat the wall behind, minimize the rear reflections. He mentioned he has a giant American Flag. I would glue a thick layer of old fashioned carpet underlayment on the wall behind the flag.

He thinks he may reverse everything in the big room, then he would have plenty space on sides, rear, and behind his listening position, that ought to be better than ever.

Maybe when setup, I’ll have him and a strong friend or two move my current speakers over there, hear them in that ’open’ setup for the first time, and he wants to compare these to the Model II’s.

If I understand your question, you are looking for something very unusual. Typically we look for the soundstage to begin at or behind the speakers… like at a concert. The stage, is where the sound comes from. The mark of a great system, in part, is it being laid back with a deep / wide sound stage.

Some speakers can be “forward” typically having a shallow sound stage… typically this is a criticism of the system because it is not reproducing natural sound.


There is a few home audio speaker systems that are are designed not so much to do the sound-staging.. but to produce a wall of sound. The ones I remember hearing were six or seven feet high, with tweeters in the middle and mid range above and below then further out woofers above and below. I don’t remember names.

i would recommend trying your system against the short wall. Making sure there is nothing taller than an amp on the floor… equipment racks typically interfere with sound staging.


It would be really helpful to see your system in its current form. There is a place for photos along with your equipment.



Most importantly, set speakers on the 15' wall, not the 20' one. Then place them at least 4' to 5' from front wall and 2' to 3' from sidewalls. Only then will you start getting the full 3D effect. By my experience anyway. 

Ability to Visualize is part of our experience, 2 channel system: all Imaging is Phantom in origin and that modified by the space.

You would think: ’How the hell does he have a dining room table in the middle of the listening area???? Keeps telling us his system has excellent imaging, WTF?


Close your eyes, tables out of your perception: everything comes from the un-obstructed L and R speakers, the Phantom Image is NOT coming from a center speaker: timing, volume differences, phase, whatever the engineers did, comes together as excellent or poor imaging.

This is why I often say: REMOTE BALANCE is a wonderful feature, a small tweak can bring the entire intended Imaging into Focus, not just the center singer, everything ’sharpens’.

It is/was much easier to perceive ’DEPTH’ in spaces with open space behind the speakers, and in fact that open space and resulting reflections/timing ... does help your brain Perceive Depth.


Another Perception Aid is Knowing Where the various musicians are seated,

expecting violins left, bass right, Woodwinds Center l/r and f/b, Horns rear, Drums rear left

i.e. Knowing,, Expecting, Perceiving that imaging IF the engineers got it right.

standard Orchestra Arrangement:




I saw the Hot Sardines Live in Montclair, then I bought a double LP of Live Performances: One Toronto, the Other Joe’s Pub, NYC.


Joe’s Pub, Piano on the Left? Piano was right when I saw them live.

Everything was ’opposite’ to my former experience and expected perception. McIntosh Mode switch to the rescue: ’Stereo Reverse’, now that is ’right’, did someone involved make a l/r mistake?

Nope, as it happened, Donna was at the Joe’s Pub performance, and that smaller stage, the Piano was on the left.

OK, now, knowing that, and being familiar with Joe’s Pub, I listened in Stereo, not reversed.

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It's unusual for a system to throw a deep soundstage. Over the years there have been several attempted enhancements to simulate depth. All of these systems manipulate phase information to trick your brain into perceiving more depth. Here are several examples. You can look up the reviews on this stuff and get a better idea what each option does. Soundstage depth has been a priority for me and I have owned several of these units.
1. Carver Sonic Holograhy C-9. Alters phase information to give the illusion of more depth. I have one and it works reasonably well but you have to carefully set it up and keep your head still when you use it. They come up for sale regularly and are not expensive.
2. BSG QOL Processor. This is the best solution I've found. They are discontinued but ocassionally one comes up for sale. It adds depth and the instruments sit in their own three dimensional space. When audiophiles hear my system with this engaged their jaw drops. I have a spare in case my first unit bites the dust.
3. Baach 3D Spacial Processor. This is the newest gizmo (or software) on the market and its generating lots of press. I haven't heard one but I'm looking forward to auditioning at least the software version. The deluxe hardware unit goes for a heart stopping $54,000. You can get a mac software version for a few grand. Like the Carver, you have to carefully set it up and keep your head in a vice while listening. The ultra fancy version actually has a head tracking function that direct the image at your noggin if you sneeze.
4. Polk SDA Speakers. Polk makes speakers that incorporate phase altering technology to improve the soundstage.
5. Yamaha DSP-1 Processor. This is a different approach in that it has an adjustable delay function for one or two sets of auxillary speakers. It can simulate a live concert to an eerie degree. It takes one or two additional amplifiers and one or two pairs of additional speakers to make it work. I have one but it isn't hooked up at the moment. It's kind of a pain but when you have it running and dialed in it is an incredible experience - especially for live recordings.

There is also an easier experiment you can do which requires a set of bookshelf speakers, stands, and a separate integrated amplifier. Setup the bookshelf speakers back to back with your regular speakers so they are firing at the front wall. Hopefully you have an unused set of preamp outputs that you can hook up to an integrated amp. Hook up the integrated to the bookshelf speakers and experiment with the volume and tone controls. If you have an equalizer hooked into the integrated you are in tall clover. This can add a nice amount of depth to your system.

If you've made it this far you realize that you are not the first person to have this issue. Depth is the holy grail of stereo reproduction and there has been a lot of attempts to solve the problem.

For the record, I'm running a pair of Thiel CS6 speakers with a Krell KSA 300S amp. The speakers are 6' from the front wall which is the best place to get maximum depth without any processing. With the BSG QOL I have a window that sounds like a deep soundstage with instruments that are placed left to right and front to back. It's pretty amazing. 

It's unusual for a system to throw a deep soundstage. Over the years there have been several attempted enhancements to simulate depth.



Good Omni directional speakers like mbl do it best but are still limited in most rooms at home unless they can be set up just right to get levels and timing of reflected sound just right. 

Thanks for the replies so far. I'm going to get a photo up tomorrow so you can see my room/setup. @baylinor: For 3 years, I had the system setup with speakers on the short 15' wall (rooom is 15x20). I didn't understand why at the time, so I bought new speakers thinking larger drivers (went to 10" from 8") would have improved the bass response, but it didn't. I ended up going to Acoustic Fields and did there free room consultation. Dennis suggested setting up the speakers on the long wall. I did that and boy- what a huge improvement. Everything was better- no comparison. I'm don't understand the physics behind it, but certainly can appreciate the positive difference. I think I must have had a nasty node/ cancellation in previous room configuration. For good measure, I was thinking about switching back again (at some point) just to double check.

What I thing would really help at this point is to be able to hear a truly great system. I need a benchmark. It would also help me understand what is possible and not in 2 channel audio. Anyone here in SoCal have an awesome room/ system I can take a listen to? 

Can't help you there, but if you are ever around Austin, just let me know. My house of stereo may well meet your high standards. Good luck in your pursuit.

Soundstage can be at least as much dependent on how a recording / track was mastered (or remastered) as it might be on speaker model / placement x room. Hard characteristic to change, but as already mentioned, DSP can help.

@veerossi if you find “truly great” systems to have a listen, either bring a USB stick with a few of the exact files you think have exemplary soundstage, or at least make sure the same streaming service tracks are available in a short time span. If you don’t use the same source file / master, any conclusions you make could be off-mark.

Easy illusion for a time and phase correct speaker….. and get the mid and tweeter about 44” off the back wall so as not to confuse the ear/brain. It’s also quite helpful to use a great reference…like Opus 3 test LP… drumroll…. Depth of Image

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Interestingly, I came across this video tonight. I swear Paul can read my mind sometimes.

After watching Paul’s video, it sounds like what I’m hoping for can be found in a surround sound system, but that’s not my cup of tea. I’m becoming a bit of a purist at really like the simplicity of 2 channel. At some point, I hope to get speakers to where I can get rid of my 2 subs.



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I also made it over to my local audio shop and took a listen to this today. I’m not sure how good this system rates in the big picture. It consists of a $40K T+A integrated solid state amp, 30K Fyne speakers, Chord Dave DAC, one of the Hi-Fi Rose streamers, and all Nordost cabling. It sounded great, but in the end soundstage and depth were not too far apart from what I have at home. Here’s the setup I listened to:


and here’s my setup at home:


I get that effect where the musicians are playing in the space in front of the speakers as well as the usual depth behind them. The speakers are completely gone in the 3D soundfield. Vinyl, tubes, Quad ESL57.  I'm not sure how that translates into your set up but perhaps tubes might help. 

I think you should start with some basic treatments, the simple stuff that is unlikely to change. Diffusion on the rear wall, absorption on the side walls, absorption on the ceiling absorption behind you. Then report back on how that affects, your soundstage

OP The depth behind the speakers is great, just not much in front of them- unless it’s one of those songs that has a part where it has that inverted phase trick. Then it washes over me. I want that all the time.

I guess you are talking about the tunnel sound or the mid-range far behind speakers. It happens when an audio system sounds unnatural which sound stage is far behind speakers. The speaker makers try to pull the sound forward but they can’t do it because the veil in front of sound images is already too forward and the veil irritates the listener. The actual mid-range is behind speaker, but the veil/glare is already hitting the face of the listener that makes sound very bright and noisy (left speaker in below video).


If an audio system sounds natural, the sound stage comes forward like the original music naturally.

Original music


A sample of natural sound system. Many systems can sound closer to this sound with right audio cables and some tweaks.   Alex/WTA

@veerossi : Seems like good speakers (assuming it is the Tannoy Turnberry). They are sensitive two way speakers, like mine, but not bidirectional like my Audiokinesis Dream Maker. I think they should be able to do depth very well, if precisely set up. Note, I said precisely. Not just OK. This is because they seem very pinpoint front sound oriented (e g compared to mine).

I am experimenting with an even more ‘puristic’ pinpoint system in my home office – single driver speakers, no crossover. The soundstage changes a lot even with small changes of speaker positioning and toe-in. One might think that frontfiring speakers were less dependent on the room and reverberant sound, compared to bi- or omnidirectional, and yes, it is partly so, but there remains a huge dependence. More than we usually think about. The speaker «cant help it», it plays the room, and together with the room, even when designed and tuned to minimize this effect.

Consider trying the short wall once more, with more space behind the speakers, and adjust in case of bass dropouts. In my room 27 x 20 x 9 feet, there is no doubt that the sound is best with the speakers on the short wall. Others have reported the same, so I wonder why it is different for you.

@erik_squires : «Acoustic treatment in dimension of concern. Diffusion behind speakers and listeners, ceiling absorbers between speaker and listener». Well said. My experience also, as a main rule. Not too much treatment, though. I had to remove two thirds of the ceiling absorbers to get it right. And speaker positioning is even more important, to my mind.

@elliottbnewcombjr «primary factor is how much space behind the speakers.» Yes. My speakers like 5-6 feet from the wall for optimal depth. So even with a more conventional front-firer, I would try 4 feet at least.

@noromance «The speakers are completely gone in the 3D soundfield. Vinyl, tubes, Quad ESL57. I’m not sure how that translates into your set up but perhaps tubes might help.» Right, works well for me also, with my Audiokinesis speakers and tube system. The better the source, the larger the chance to hear depth and detail.

Someone wrote, I would like the audience applause in a live concert recording to sound in front of my speakers.

Not sure if I can reproduce this effect in my system. Will try. Suggested test recordings, anyone?

First of all you should change your speaker placement, you should always put the speakers firing down the longest length which is 20 ft and then go on the Cardas site and you can plug in the 15-ft width of your room and it'll tell you exactly where to put your speakers, I did that and it totally opened up my sound stage, and then you should get the Townshend podiums to stop your speaker vibrating it was the most significant upgrade I've ever done to my system they're not cheap but well worth it.


I wish you would have named the system that that singer is singing on it sounds very natural even through my phone I can hear how nice it is.

In my experience I started with by-amping Adcom 555s . It sounded amazing but only a 6 foot circle in the center of the room between the speakers . When I upgraded to the mc452 that was a whole different story. Soundstage grew exponentially. My room is of similar size 15/20 with speakers set up along the 15 foot wall 7ft. apart. The soundstage grew from 6ft. circle to the whole back of the 15ft wall. My opinion is for a better soundstage is amp, amp ,amp.

Try playing Moon River by Jacintha to get a perspective of image placement and over all system sound.  

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Your perception of depth of soundstage is most likely negatively impacted by the first reflections (side walls, ceiling). Also, adding bass traps will help solidify the soundstage. When your brain needs to process sounds bouncing off every reflective surface, it will have a tough time realizing the stereo image. 
Easy way to test it is at very low volume where the reflections are minimal, does the depth increase?

Let's consider some of the basics of perceived soundstage depth.  Sounds that seem way behind the speakers have reverberation which is either natural--from distant-miking--or artificial.  Sounds that emanate from the plane of the speakers are typically close-miked without much reverb.  To have sounds in front of the speakers in a stereo system would require that the phase was reversed.  Or maybe it can be done with a surround system.

With regard to southern California dealers, I thought Alma Audio in San Diego did a nice job of setting up their Boenicke W8 speakers to create a sense of depth. The sound was very enveloping. Nice looking speakers that sound excellent, imo.

@veerossi adding to my earlier post. Now that I saw your system….very nice! But I’m afraid, in addition to room acoustics, lack of preamp is contributing to the soundstage limitations you’re experiencing. 

It sounds like I need to finally get going on my room treatment. I’m not sure there’s much left for improving speaker position in the room. My speakers dissapear 90% of the time right now. I need to finally buckle down and learn how to use REW.

Earlier I spun the Mofi Brothers in Arms and on "So Far Away From Me" I get the sound wrapping around the room- almost like it’s giving me a hug. My thought is: somewhere there’s a treated room with a properly setup system that can do this full-time. I’m holding on to this as a goal.

Not seen in my photo is the rest of the gear that’s against the back wall. I will try going back to the short wall for the setup, but will need to muster up the energy for that chore first.

@8th-note The BSG QOL Processor sounds interesting. Do you recall how much it cost?

@o_holter One of these days, I need to hear Quads. For a long time, I’ve heard so many great things about them.

@testrun Wow, that Moon River is a spectacular recording. It's ASMRish! Soundstage is massive!

@audphile1 The depth doesn’t change much at low volume, but I can tell when I’m at the right volume. There is a volume where the pressure in the room is just right. Too little and it’s a bit dull. Too loud and it overwhelms/ excites the room. Using my phone and the DecibelX app, around 70-75db works well.

u r chasing u tail….if your system can do it on a recording but not others….



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u r chasing u tail….if your system can do it on a recording but not others….

This is correct (hence my previous comment about soundstage being largely recording- / master-dependent.

I’d find other well-performing systems to play my preferred files on for comparison before altering my system. If 90% of what you listen to has a soundstage you prefer on your system, I suspect you are near the lead of the audiophile curve. Some recordings just won’t permit it.

Plenty of anecdotal accounts where using DSP to focus stereo imaging had a reductive effect on soundstage size, just FYI.


The BSG QOL originally retailed at $4K. They show up used once in a while for around $800 to $1K.


mihorn, I wish you would have named the system that that singer is singing on it sounds very natural even through my phone I can hear how nice it is.

My system consists Oppo 95 (modded), Bakoon int. amp (modded), and Wavetouch audio speaker with Wavetouch cables. Here the system video. Alex/WTA

Soundstage depth is accomplished by a recording mixer by using relative volume level adjustments on isolated or semi-isolated instruments, and width is from panning from the middle outwards. That's it. Vibration controlling silliness or room reflection worries are minor or irrelevant.


You are leaving out a major mixing tool for creating the illusion of depth in recordings. Reverb and delay on particular instruments/tracks is, in my experience, the most effective way of creating depth in a recording.

Reverb and delay add reverb and delay, and not depth particularly in my experience. Maybe an illusion is enough, but level is key and burying an instrument in reverb tends to obscure its position in the mix more than accent it. Listen to the infamous brilliantly recorded later Steely Dan recordings...one of the first things you notice is the utter lack of reverb.

"Listen to the infamous brilliantly recorded later Steely Dan recordings...one of the first things you notice is the utter lack of reverb"

I'm listening in my head...

Skunk Baxter's  "Bohdisahttva or Walter Becker's "Josie" solo would have been ruined with noticeable reverb. OD tone/reverb is an odd pairing to my ears. 1-2 max on the knob- if any.

Those geetars are dry!

wolf on point.



It’s in no way a matter of cabling and tweak products such as vibration absorbers, contrary to what the either delusional or perfidious dealer suggested here. Yeesh…talk about misleading.


The primary factor is how much space you allow between the speakers and room boundaries. Additionally, bass smoothness, proper room treatment for ideal decay time, the phase of the recording, and overall speaker performance also play critical roles. All the rest affect perceived depth by far smaller margins.

I’ve setup systems that can create incredible depth for relatively little money, so it’s not so much about how much you can spend, but high quality speakers are a must. 


I see quality loudspeakers there. Wide-angle distortion in the photo makes it difficult to estimate the ratio of tweeter-to-tweeter and ear-to-tweeter. Some say that these should be equal (an equilateral triangle); however, most great-sounding systems I've heard have the speakers a little closer together. Tweeter-to-tweeter distance is ~85% of ear-to-tweeter.

I agree with others that for most loudspeakers to create a perception of depth, you're going to need to pull the speakers well out into the room…at least 4 ft from the front of the speaker to the wall behind. Sometimes further is better. It also helps for there to be nothing between the speakers. Bonus points for having nothing inside the triangle formed by the tweeters and your ears.

Good luck. It's something we're all chasing and have achieved to various degrees.

It’s all about setup. There are several excellent books on setup. Buy one, read it , learn how to setup your room

Note that unless you've never actually owned a stereo system or you have no faith in your own taste, the proper setup is what sounds best to YOU.

I went on the search for greater depth and have concluded it is a bit of a myth.  My speakers are 4' off front wall and 3' off sidewall.  My side reflections are treated. I have a fabulous sound stage and very holographic sounds.  There is depth but not to the degree some describe (i.e. behind and outside the front wall.).  

While it sounds counterintuitive, side wall reflections impact the width and depth of your sound stage more than I ever imagined.

As you consider room treatments, read a few articles written by Art Noxon, owner of ASC (Acoustical Sciences Corporation) Tube Traps. 

I like his tube traps because you can literally “dial in” the soundstage by simply adjusting the amount of diffusion and absorption you need. 

Use a mirror to find your 1st and 2nd side reflections, and watch your soundstage adjust to meet your needs. 

Hope this helps.


labpro is correct that sidewall reflections affect image depth...all other things being equal, by moving speakers closer together you can increase soundstage depth but at some point it's at the expense of sounstage width. It's an iterative process, and almost every room is different...