hey guys -I am running a full ATC system- The big 100's, c6 center, c6 sub and right now 2 sets of the 20's -all active- My question is right now I have the big c6 sub handling everything under 80 HZ- would I gain anything by going to the big 100's for the side speakers or since the sub handles most of the bass am I not gaining anything- My side speakers are roughly 8-9 feet from the listening position- thanks for all your help- gary

If you have a later Lexicon model (version 4 of DC-1, all DC-2, and all MC series), sides that go down to 40 Hz may be useful for the Bass Enhance feature. If you listen to discrete multichannel recordings, full-range sides may be useful if the recordings are done in a certain way.

In the real world, bass envelopment is a very real and beneficial effect, and if you listen to recordings that preserve this kind of sonic cue, then full-range sides are good to have.

--Andre

Andre- thanks- I am using the Meridian 861 4.2=

To me is not that much the frequency response (as it can be handled with bass management- Doesn't the 861 decode rear sub data? it was promised in 1998).

To me a good front speaker must be directivity controlled Far Field Type, the surrounds should be near to mid field type, hence my opposition to the ludicrous idea of 7 exact speakers.

In small spaces (less than 50' x 100' for example), the locations for speakers which produce the best imaging and best envelopment simply are not the best location(s) for low frequency drivers for smooth bass response in the seating locations. Thus physically separating your low frequency drivers allows you to set up speaker locations that provide best imaging/envelopment AND smoothest bass reponse.

In small spaces (less than 50' x 100' for example), the locations for speakers which produce the best imaging and best envelopment simply are not the best location(s) for low frequency drivers for smooth bass response in the seating locations. Thus physically separating your low frequency drivers allows you to set up speaker locations that provide best imaging/envelopment AND smoothest bass reponse.
But it is not an either or proposition (i.e. one could use full range speakers AND subwoofers to obtain the smoothest bass response).

Take some of the load off the single 15 driver in the sub. Another and perhaps better option might be to get a second, or third, or fouth :D ,sub. With all the juice you have now, I think at least one additional sub is the way I would go and perhaps keep the current surrounds. You can use the additonal sub to help even out the base. I am running two subs now and I wish I would have done that years ago.

But it is not an either or proposition (i.e. one could use full range speakers AND subwoofers to obtain the smoothest bass response).
Not very likely.

Not very likely.
So oneobgyn should trash the Wilson X2's that he uses in combination with his XS sub and replace them with satellites?

I use 7 x Meridian DSP5500s and 2 x Meridian SW5500 subs in my room.

Mark

So oneobgyn should trash the Wilson X2's that he uses in combination with his XS sub and replace them with satellites?
There's nothing wrong with a sub-sat configuration (with good speakers). He has be be very careful with the X2s due to their poor off axis response; but, since he likes the X2s, get a third X2 for the center and another XS sub. Then have the room professionally calibrated. The odds are exceptionally high that the end result will be a much better sounding space and the crossovers set such that the lower end of the Wilson's are not being used.

Dennis,

At one point are you suggesting the lower end on the X2's be crossed over (approximately)?

the locations for speakers which produce the best imaging and best envelopment simply are not the best location(s) for low frequency drivers for smooth bass response in the seating locationsThat's something I've repeated (almost verbatim) in threads about full range speakers vs sub/sat set-ups. However, achieving the smoothest response across multiple seating locations might not be the top priority for everyone, and that's where full range side speakers can be useful.

The maximum output crowd tends to pile their subs one on top of another, placing them all in the same corner (a la Nousaine). Folks wanting consistent low frequency response (not necessarily the smoothest or flattest) across multiple seats, can use 2 or 4 subs along the midpoint of each wall (a la Harman's Toole, Welti, Olive).

Others will prioritize low frequency envelopment and externalization (stereo bass) as the most important quality for them. As Andre mentioned, this is more easily and effectively accomplished by having low frequencies coming from the sides of the listeners, either using a pair of (stereo) subs or full range speakers at the sides.

Sanjay

Others will prioritize low frequency envelopment and externalization (stereo bass) as the most important quality for them. As Andre mentioned, this is more easily and effectively accomplished by having low frequencies coming from the sides of the listeners, either using a pair of (stereo) subs or full range speakers at the sides.


Also note that people into bass envelopment (vs. higher frequency envelopment that Dennis refers to) will not suffer from the same kinds of problems that people who listen to mono bass do. The Harman paper addresses the problem of reproducing mono bass accurately. Once you have multiple decorrelated bass channels, the rules change.

I should also point out that just because you have 5 full-range speakers around you doesn't mean you have decorrelated bass. Either it has to be on the recording already, which is unlikely for the vast majority of recordings out there, or you have to have a feature like Lexicon's Bass Enhance to change it for you.

--Andre

achieving the smoothest response across multiple seating locations might not be the top priority for everyone, and that's where full range side speakers can be useful.
Actually, even with full range speakers, the statement is still true. This is simple physics and no speaker has been designed to violate the laws of physics. Once the speakers (and the single seating location) has been established for best imaging/sound stage, the odds you'll have smooth base response at the seating location is virtually nil.

The use of multiple subs, following the Harmon method, will provide the most consistant response across a wide area...it will, at the same time, provide smoother response. Multiple subs will NOT solve all the problems; however, multiple subs will make the process to calibrate the bass easier (across one, or multiple seats). The follow on process requires equalization and room treatments. One area not addressed (yet) in the Welti work (although Todd, Floyd and I have had discussions about this), is the use of phase and SPL adjustments to multiple subs to further reduce the work required of treatments and EQ.

Stereo subs have been shown, time and time again, to provide no "stereo" or added "envelopment". In fact, when these effects have been observed, it has been shown that the purported 'localization' was really the use hearing the mechanical and air slap noises from the sub woofer(s). Once these noises were eliminated, the "stereo" effect disappeared.

Stereo subs have been shown, time and time again, to provide no "stereo" or added "envelopment". In fact, when these effects have been observed, it has been shown that the purported 'localization' was really the use hearing the mechanical and air slap noises from the sub woofer(s). Once these noises were eliminated, the "stereo" effect disappeared.

Envelopment is not localization. I'm not sure what conclusions one can draw from these tests if they conflate these two concepts.

--Andre

Once the speakers (and the single seating location) has been established for best imaging/sound stage, the odds you'll have smooth base response at the seating location is virtually nil.Not disagreeing, just pointing out that smooth bass response might not be everyone's number one priority for low frequency reproduction. In fact, when these effects have been observed, it has been shown that the purported 'localization' was really the use hearing the mechanical and air slap noises from the sub woofer(s).The idea behind stereo bass is not to localize low frequencies. Mono bass tends to sound sorta like it's in your head; stereo (decorrelated) bass sounds externalized and all around you. The opposite of localization.

Sanjay

You are both exactly correct. "Localization" is not "stereo" nor "envelopment"; but, "stereo" bass is not necessary "decorrelated" (and usually is not). By the same token, without "localization" (ie, the ear can determine the source and direction of the sound source), you cannot have a stereo effect. At low frequencies, you cannot determine directionality, therefore you cannot have stereo imaging. Even slight timing differences between microphones at the low end of the spectrum, cannot be determined.

I agree, smooth bass response may not be a priority; however, I'd tend to think someone spending that kind of money on equipment would be seeking accurate playback and, in the absence of smooth response, accuracy is rather lost. On the other hand, in the Hip Hop world, well, all bets are off. :)

"but, "stereo" bass is not necessary "decorrelated" (and usually is not)."

Which is what Bass Enhance in Lexicon's is all about. It in effect decorrelates mono bass in the source to introduce inter-aural timing differences that would occur naturally in a hall even from a mono bass source.

"By the same token, without "localization" (ie, the ear can determine the source and direction of the sound source), you cannot have a stereo effect."

Out of phase material in L/R is diffuse and not really localizable either. Does that mean it isn't a stereo effect? Of course not.

"At low frequencies, you cannot determine directionality, therefore you cannot have stereo imaging."

As Andre and Sanjay have both stated, this isn't about directionality. There is more to perception then just pointing to where a sound originates from. Stereo bass response, with either actual stereo recorded bass or Bass Enhanced material, is perceivable when reproduced over stereo subwoofers as compared to mono subs. The effect isn't pointing to where the subs are located but hearing the bass sort of leave your head and the apparent size/spaciousness of the room increases.

Shawn

Even slight timing differences between microphones at the low end of the spectrum, cannot be determined.

Is that so? I have done experiments and have an idea of the magnitude that's audible, but I'm curious how large a difference you think there has to be at, for example, 60 Hz.

--Andre

hey guys -I am running a full ATC system- The big 100's, c6 center, c6 sub and right now 2 sets of the 20's -all active- My question is right now I have the big c6 sub handling everything under 80 HZ- would I gain anything by going to the big 100's for the side speakers or since the sub handles most of the bass am I not gaining anything- My side speakers are roughly 8-9 feet from the listening position- thanks for all your help- gary

Hi Gary,

I have four ATC 50s (2 active and 2 passive right now), a C6 Centre channel and 2 JL Fathom subs. In my unfinished room I found it best to crossover all speakers and send the bass to the subs. However, once Rives is done with my room I'm hoping to get ATC 150 towers up front and run all channels full-range.

I think that that the ideal setup is very dependent on the room - some rooms will support good bass from all channels in which case it's reasonable to run all speakers full-range. I suspect that most rooms aren't though, so it's worth checking with test tones etc...

The reference room at Widescreen Review has identical full-range speakers in all positions in an optimized room and they swear by it.

I'm going to PM you some ATC questions.

The Bogg