Axiom Home Page Forums General Discussion Home Theater Ditching front QS8's

I have a 7.1 system with 4 QS8's. I find the forward QS8's just are not directional enough. I think a blend of back surround QS8's (for general ambient sound) coupled with single direction forward surrounds would be the best of both worlds. I find I have to crank the QS8's up to high to get decent directional sound so my idea is to use M22 on wall speakers for the front surrounds. One possible problem I see is the specs are different but hopfully not critcal. Other ideas would be appreciated or if you think this set up would cause problems let me know.
Thanks!

Are you using the system more for multichannel music or for movies ? It seems fairly common to prefer directional speakers for surrounds with music, and QS8-style surrounds for movies.

One trick I saw was to use directional speakers for *rear* surrounds, QS8-style speakers for *side* surrounds (what you referred to as front surround), then wire the surround channels from your music source to the rear surround inputs rather than side surround inputs (obviously this works better with analog interconnects ;)).

That seemed to be a good "best of both worlds" solution and one day I hope to have time to try it.

Depends on what you are trying to do. Like many, when I had a HTIB system, I cranked the side surrounds to hear lots of surround sound directly from the speakers.

However, as my system grew and I learned more, I learned that if you correctly calibrate your system so that all speakers are equal, that you not only get surround sound appearing from the speaker itself but all of a sudden, it can appear to be emanating from almost anywhere in the room.

If you think of the stereo effect up front, (meaning sound just doesn't appear to be coming from exactly the left speaker or exactly the right but can appear to be coming from anywhere in between,) producers also mix their surround sound effects to do the same between the front speakers and the side surrounds and rears if you have them and there is a 7.1 track.

If properly calibrated, a plane flying over doesn't just suddenly switch from the front to the side speaker. Instead, you will hear the plane in the front and the plane will literally travel through the room inches at a a time from front to side to back, giving you a much more realistic and 3D experience.

Opinions may vary, but around these parts the general consensus is that bi or quad-polar speakers are very good at creating an enveloping sound as side speakers. For rears, some people like a bit more direct action and go with a directional speaker in the rear. Yours is the first time I have heard someone say they might reverse this.

My suggestion is to try calibrating your speakers first. It's fun and meters can be had from just 20 bucks up. It will take you a while to get used to what you might mistake as "less" surround effects" but in quality mixed movies, you will get even greater enjoyment when sound starts coming from all parts of your room, not just the speakers themselves.

Examples:
One of my favorite demos to watch peoples's head turn as they follow a particular sound as it does a slow but complete 360 around the room, is in the the 'extras' video track of "only" on the Nine Inch Nails DVD called "Beside You In Time". Reznor mixed this version of the song in 5.1 and obviously spent a lot of time playing with the placement of the various sounds in the song. This particular sound effect crawls slowly around your room like a bug on the wall.

On the movie side, in one of the early scenes of "Master and Commander" when the camera is moving around below deck... you hear someone walking or something above deck and the sound actually appears to come from the left part of my ceiling. Totally freaked me out the first time I heard it as not only was it in between my fronts and my surrounds but it also 'appeared' to be coming from above.

In the end though, do what makes you smile.

bridgman,
My goal is strictly movies. I'm a little confused about your wireing. Are you saying to wire the rear directional speakers to to "side surround" output on the AV receiver? I have thought about that but think it might sound wierd. I am using HDMI for my whole home theater BTW. I have played with all the possible settings on my Denon AVR-3311CI including the auto calibration but find that the QS8's just don't play loud enuf to give good direction for me. The front L/R M80's seem to over power the surround channels even when turned as low as possible and the QS8's cranked. In fact, I think I may have destroyed my QS8's because now they all have distortion. In the end I just want a killer movie setup. My system has the EP800, M80's, VP150, and 4 QS8's. I am totally blown away with everything but the surround sound. I don't have room for 4 more M80's for surround but I bet that would do the job...lol. I realize that surrounds are just for ambient and special FX but when I see action traveling left to right and front to back I expect to hear the same from the surround speakers with them increasing and decreasing in volume and the other channels acting the same way. I know it's also all about the movie sound track mix. I have the perfect spacing and position for all my speakers and only want one listioning position.I have not tried a sound meter because I thought audesy cal was the best. I have a lot to learn about home theater and appreciate any imput.

Update: just spoke to Brent at Axiom and more then likely my calibrations where way off initialy so I never really have heard the true QS8's before blowing them. Major thanks to Brent and Axiom for working to fix this under warrenty even though it's really my fault. I will definately be a return customer!

Great customer service as usual.

Next time, stop in here first before doing anything that just seems wrong, like needing to get the QS8s cranked to your liking. Clearly something isn't quite right, and we are all most than willing to try to help out. Plus, you should be able to get the results that you want without nuking your speakers. We are all hobbyists here that love great sound, and really like to share knowledge with each other so that others can experience great sound to.

Let us know when the QS8s are back up and operational and we'll all try to get you squared away!

I'm a bit confused, the point of "side" and "rear" surrounds (not front as you say) is to not be directional, that is the point. They are supposed to envelope or wrap you in the experience, not be diretional.

When you say "forward" surrounds, I hope your talking about the "side" surrounds which should be to the sides of the listeners?

The surrounds are for movie affects and background sounds during movies, unless your talking about cranking up music on them, which they are able to handle power.

My guess is you have something calibrated wrong, or placement is wrong. They should be set to "small" after you run your setup, and probably end up with a crossover around 90hz or higher.

Drifter, although you've said that your speaker positioning is "perfect", you also referred to the "front" surrounds, so that raises a question. There are side surrounds, which in a 7.1 setup should be directly to the side of the listening position and maybe 2-3' above ear level. The back surrounds on the rear wall should be separated about the same distance as they are from the listening position and also be about 2-3' above ear level.

If they're already well-positioned, the next point would be that they're calibrated for a level that blends well with the front speakers(your auto-calibration on the receiver should do this nearly perfectly, better than you could judge by ear). Many sounds aren't meant to be "directional" and to be clearly heard as coming from the surround speakers. If your surrounds are correctly positioned and level-calibrated you should be hearing what the producers of the source material intended.

Sorry for the confusion as to which speakers I'm talking about. I mean the side surrounds but for now I wont be changing anything until I replace 6 woofers, that's right, 3 out of 4 QS8's I fried. JohnK, my speakers are positioned as you say, maybe off an inch or two. This brings up some questions for me and please remember I'm new to home theater setups.

1. My denon AVR-3311CI is 125W for each surround speaker and the QS8 is 400W. I didn't think it was possible to harm the QS8's with 275W left over for the speaker. What is going on here?

2. Would a separate power amplifier help to increase sound quality in both high and low volume? If so, wouldn't the risk of damageing the speakers be even greater?

3. The Axiom A1400-8 is $3,880.00 so I'm wondering how much differance this will make. My whole system wasn't much more than this so can I expect at least twice the performance or are we talking about a small change in quality. Again I'm after movies with great surround sound. My EP800, M80's, and VP150 already work great.

4. I was advised to manually calibrate the speakers with a sound meter starting all speakers at zero DB. Has anyone done this? if so, how can it be better than the Audyssey set up?

These are my current Denon Audyssey settings:
Channel Levels
Front L = -6 dB
Front R = -6 dB
Center = + 7 dB
Surround R = -4.5 dB
Surround L = +9 dB
All speakers set to small and all distances were right except for the sub which is 12ft but audyssey thinks it's 23.7ft.

I was told that by doing the calibration manually I shouldn't need to go more than 2-3 dB above and below zero dB. So why do my Audyssey levels vary so much and what is going on with my sub distance. I have done the auto cal several times and get simular results. Also I'm calibrating to just one listioning position.

Thanks!

I will work from the bottom of your post on up...

Wow. I was wondering the same thing about the larger variances in dB from say Surround R and Surround L.

Room treatments and acoustics will make a difference, but that still seems like a lot.

I've seen sub distance estimates being off due to echo and wave cancellation, etc, again based off of room acoustics.

As for using an SPL meter, I haven't done it, but I have been told and have read that it is the best way to do it. I will let others that have actually done it speak about that point.

Separate amps (from decent brands) will pretty much always provide a better quality sound, and yes will boost output volume.

I will let someone else also talk about the watts. One thing that I will say is that if you start feeding a quality speaker a distorted signal or have too much receiver clipping even, at high volumes, this can damage any speaker.

There are a lot of mathematical numbers around what a watt means in comparison to sound levels and such, but like I said, I will let someone else speak to that.

The DSP in the EP800 will also add to the sub's distance setting. Mine show up as 28 feet or so away despite being only maybe 8-10' away.

Something does sound funky with the disparities you are describing so it is really tough to know for sure what's happening but it sounds like it's getting figured out and rectified.

Just thought I'd take a stab at question #1 How can you blow a speaker that is 400 watts with just a 125 watt amp?

A good question and many years ago, I thought exactly like you. Basic Math right? However, I'll take a stab at how the opposite can be true in layman's terms.

I don't know how loud you were trying to reach or what issue was creating the need to drive certain speakers louder than others but in regards to question #1, if you keep requesting more volume , essentially the speakers will attempt to suck more and more power from your amp. Because the speakers are rated higher than your amp, you eventually reach a point where more wattage is needed than the amp can actually dish out. The speakers are not maxxed out, but your amp is.

The amp, will try it's best to a certain point. However eventually it can no longer produce a perfect sign wave of signal. The lows and the highs get cut off. If you were to run the signal through an oscilloscope, it would look something like this.


Speakers HATE signals like this as they are supposed to vibrate smoothly in relation to the signal wave. This effect called is "Clipping" and it can and will damage speakers, at the very least it creates distortion. Often amps have protection circuits built in to shut things down before it gets too severe but it does commonly happen to a point if you drive to much volume.

Short answer:

A big wattage amp can indeed blow low wattage speakers
but
an underpowered amp can also damage even high wattage speakers because it can't handle the job.

Am I saying you need a bigger amp? No. Not unless you enjoy ear damaging volumes or your room is huge. 125 watts is fine for most people. Essentially, if you are playing with the volume button and the sound starts to sound distorted or simply worse instead of better, you have driven your amp into clipping. If you hear clipping but you still want to go louder, then yes you definitely need a bigger amp...... and probably a hearing aid down the road (room size aside).

I have no idea what was the 100% cause and effect of your issues but I thought this bit of trivia would be handy to know in any case.

Thanks Murph. I knew that someone could explain it better than I could.

Ditto Murph...picture and all.
I have a denon AVR-3311CI and it confuses me the relationship between "channel levels" and master volume. If I set everything manually to zero dB the front L/R speakers overpower the center and surrounds. So I would think I should increase the center and surrounds by maybe 3 dB to compensate. Now forget the surrounds and lets talk about the center.

When I increase the dB for the center using audio adjust "the staic sounding test" I get close the the fronts and think all is well with my level adjust. It seems 2-3 dB is enuf to make the center sound even in volume to the fronts but when I play a movie the center sounds muted and lacks bass compaired to the fronts by a large amount. I try to increase the center even more but still I get the same effect, more volume but muted and lacks bass, like the woffers don't work right. So it's like the center level adjust doesn't work in an actual movie.

The only thing that makes the center sound full like the fronts is using the "matrix" mode and I think all that does is mix the sterio from the fronts into the center, not true 5.1. I have no clue but it's the only way I have found to get the center even in tone and volume to the fronts.

Shouldn't I just be able to start a movie and the denon select the surround mode so that the center is separate from the fronts or am I confused about "matrix" mode? I try direct and pure modes but the center then goes back to sounding muted with little bass. What is matrix mode anyway and why is it the only thing on my reciever that makes the center sound full like the fronts?

I have played with all the manual input modes like dts and dolby but none give me the full center tone like matrix mode. Is this normal?

If your watching movies, the display should say something like Dolby Digital for example, or DTS if your in that mode for Movies. Sometimes you might see PLIIx during the DVD menu previews prior to the movie. Direct and Pure modes I believe are more for music listening and disregard your bass management modes for movies.

The Center channel is more for dialog in movies and surrounds for surround affects. I'm still a bit confused what you could have been cranking up to blow the Q's.

It doesn't matter if you set the levels for each speaker to 0dB or even -10dB to start, as soon as you run Audyssey they all get reset and changed based on the test results. If your doing it manually, normally people get an SPL meter and match all the speakers to the same pink noise around 75dB or so...

Drifter, I'll try some of your questions.

2. and 3. No, a separate amplifier with a higher maximum power rating doesn't help the sound unless the speakers are playing so loud that the higher power capacity actually is used. Your 3311 should have plenty of power for your needs. The A1400-8 has been unavailable for some time and it's uncertain when or if it will be.

4. The major differences in how the center speaker and left surround were set would seem to indicate that those speakers were either defective or damaged so that they had to be set much higher to match the loudness of the other speakers. No, calibrating manually with an SPL meter doesn't give more accurate results than the Audyssey(or any other)auto calibration system. It adds human error in reading the meter, and, if anything, is less accurate.

Yup. Head nods everywhere.

Common consensus is that if you have Audyssey and a proper mike that came with it, at least use it to calibrate your speakers to equal levels. This will give you the best results to re-create the spacial audio effects as they were intended by the creator's of the film/music. There is a second phase where it corrects for your unique room characteristics across all the various frequencies, but that is another discussion.

In the absence of a receiver with an automated system, use an SPL meter to get them all as equal as possible.

After calibrating the levels to be equal, many people do in fact tweak the numbers just slightly. Especially the center channel. It's very common, to turn up the center channel a db or two in order to get more clarity in dialog, a track that often seems mixed a bit light in movies. If you have ever held on to the remote to play constantly play with the volume controls between dialog and action scenes, you know what I mean. This will rectify that problem without throwing the spacial effects off too much.

Finally, while Johnk is correct, Audyssey probably does do a much better job at calibration vs. the SPL meter, I simply can't resist my inner geek to break it out once and a while. Sorry John, but I do love gadgets, even when my brain tells me I don't need them.

Thanks agin, this post is morphing into other subjects now so I think it's time to kill it.

I usually bump the sub up some too.

Do want auto-calibrating receiver... not a great time to upgrade right now, though.

SPL just focuses on volume and not trying to correct room issues, but many people swear by it. Do some sort of regulated calibration (either built in to the receiver or get an SPL meter) and see where it takes you. Maybe you are like I was a few years back where I used to love having the surround channels turned up to make things seem more dynamic. I still run my surround a bit hot, but only a couple of dB. With my new theater under construction, it will be interesting to see how I tune it since it will be a more ideal room with sound control and treatments of the room itself. Maybe I've just been compensating for less than ideal room acoustics.

Posts never die here. We just keep changing subjects until eventually we make fun of Mark's square room or Bigwyres makes an appearance.

Isn't that the truth.

Hey, we have a new restaurant where I used to live (Des Moines, Iowa area).

It is called Zombie Burger!
Zombie Burger + Drink Lab

I hear that it is pretty good.

You guys wont believe this but all that other trouble I was haveing with auto cal and the center speaker ended up being blown woofers in my center now. I must be an idiot but I learned to not crank it so loud. My indestructable EP800 fooled me into thinking I could crank everything. Can't wait to get my new woofers now. Will definatly post again before adjusting my system...Thanks JohnK, you were right about my center speaker being bad.

We all live and learn. No shame in that. That is how we progress. Make sure you let us know how things sound once all is back together.

will do.

Andrew, I know you were kidding with me about the SPL meter "gadget", but I certainly have had the Radio Shack digital model(far superior in different measurement modes available)for years and use it often, but not for speaker calibration anymore. I use it to verify that the listening levels I use at various times for music are safe and that the amount of power that my receivers can supply is in fact more than needed, even on brief peaks.

An interesting task I've given it a couple times is when I've taken it to a concert with me to test for orchestral sound levels. I had to reassure some of the other patrons that it wasn't a bomb. When I explained what I was doing they probably still thought that I was a nut, but not a dangerous one.

Unless you had the receiver at +15 or higher on your dial for extended periods of time, clipping the speakers, I find it so hard to believe you blew all those drivers. I just have never heard of this in the time I've been a member here.

Back when I was trying to isolate my POS Emotiva amp shutting down problems, there was a time where I drove just my rear Qs8's as front channels at +15dB on the volume dial for about 5 minutes. Now the dispersion was different than a direct radiating speaker, but they didn't break a sweat and I wasn't even touching the 400+ watt rating.

I just don't see how you could blow all these drivers unless someting is hooked up wrong, or your receiver is set wrong.