Mains set to Large?

[CECAA850]

 

I'll be the voice of dissent then.

 

If you're mains cabinets are tuned to 32Hz and you feed them a really hot content with a lot of 20-25Hz stuff, the box will no longer be protecting the woofers, causing over excursion and damaging the drivers.  I would certainly think it would be possible.  Probable is another question.

Personally I think crossing your mains over at 40 hz gets all the benefits of running as large but with added protection from situations like this. I'm not sure you could tell the difference on movies.

 

 

 

Agreed.  The crossover isn't a brick wall and you'll still get some content below 40 Hz sent to them.

[timdog5000]

Do most of you use the EQ on your subs? I have mine disabled, is there an advantage to setting the eq on the sub itself as opposed to disabling and using AVR?

[Zen Traveler]

 

for most the question would be which would hit those notes more efficiently-speaker or sub.

Anything below 80 a sub is always going to be more efficient. That's not the whole story though.

Let's say you have one sub, which is boosted 6 db, located in your front right corner or behind you, your crossover is set to 80, even though your towers could handle lower. This is a pretty common setup. Let's say that you're watching a movie and a low male voice around 80 hz is sent to your front left main. Which do you think would sound better:

1. that voice coming through nothing but that left main like it was recorded

2. the upper frequencies of the voice coming through your left main while a 6 db hot version of the lower frequencies of that voice coming through your subwoofers on the other side of the room, which is exactly what is going to happen here.

This is a very real possibility. Same scenario happens with gunshots and common musical instruments. A low E on an electric guitar is 82 hz and drop D tuning is even lower, I think at 73 hz. No reason to send that to your subs in my opinion. Bass guitars can really get goofy, you can hear them jamming through the mains and it sounds nice, then suddenly they get below the cutoff and you get some exaggerated notes that are of a different tone and possibly from a different location. The more your mains can handle the more this stuff is prevented.

 

Fwiw, I can understand where you are coming from (especially in less than ideal settings)  but have experienced none of the above crossing over most of my speakers at 60 Hz and having front and rear RSW subs. Bass notes sound natural and as if they are coming from the direction they are supposed to as well as gun shots and the like...YMMV

Edited April 24, 2015 by tkdamerica

[CECAA850]

Do most of you use the EQ on your subs?

 

I have an external EQ (Behringer BFD) and use room correction software in my pre-pro as well.

[Paducah Home Theater]

Do most of you use the EQ on your subs? I have mine disabled, is there an advantage to setting the eq on the sub itself as opposed to disabling and using AVR?

Depends on what kind of EQ it is. Many people's "EQ" including mine is actually a DSP which is much more powerful than anything on a typical AVR.

[derrickdj1]

Should I Set My Speakers to Large or Small?
People always ask this question. The answer is very simple. If you own a subwoofer that outputs good bass sound, you should set all your speakers to SMALL. In general, if you own a subwoofer, it may be wise to set all your speakers to small for several reasons:

1. When there is an overlap of bass sound from the front speakers and the subwoofer, you will get bloated and boomy bass.
2. A subwoofer can play low frequencies all the way down to 20Hz or lower. Even relatively large front speakers cannot go that low.
3. The placement of a sub in a room is the primary factor in receiving good bass sound. You cannot adjust the position of the front speakers and move them to the side or back.
4. If the subwoofer and the front speakers play the same bass frequencies, there will be a possibility of phase cancellation of certain bass frequencies.
5. Redirecting the bass to the subwoofer relieves the receiver/amplifier from having to work on reproducing the low frequencies and this greatly improves the headroom.
6. If you are using the Audyssey MultEQ calibration, you will get much better bass performance because the MultEQ subwoofer filters have 8x higher resolution than the filters for the other speakers.

People have a psycological difficulty with the word SMALL. They have spent good money on their front speakers and get insulted when the AVR sets them to SMALL. Remember that this is not a personal insult against you or your speakers. My Definitive Technology front speakers have 15" built-in subwoofers with built-in 300 watt amplifiers. In addition to those, I have six external subwoofers in my HT room. When I set the front speakers to SMALL, the quality of the sound (both music and movies) improves.  http://forum.blu-ray.com/showthread.php?t=95817

 

With the mains set to small there is and additional 3-5 db headroom for the midrange.  There is less intermodulation distortion since the woofer has less surface cone breakup. 

 

A nonlinear system generates new spectral components which are not in the stimulus. In addition to harmonics, the fundamental components interact with each other and generate difference-tone and summed-tone components in the output signal (see figure below). In the time domain the intermodulation causes a variation of the phase (instantaneous frequency) or an amplitude modulation of the envelope. Loudspeakers and other electro-acoustical transducers generate significant intermodulation distortions in the audio band which have a significant impact on the perceived sound quality.

 

Power management is another important factor to consider.  This topic comes up often and I have never seen a good scientific argument for setting the speakers to large. I feel it sounds better is not scientific, lol. The RF 7's are rated to 32 or 34 Hz but, add average listening position of 10-12 and the distortion goes up compared to the 1 meter measurement in the specs.  There is nothing magical about setting the speakers to LARGE or using a XO of 40, 50, or 60 Hz.  The only real purpose of the XO is to protect the speaker when using avr's with autocalibration.

 

Ok, I went a little overboard.

Edited April 24, 2015 by derrickdj1

[Sancho Panza]

Wgas if it is scientific, or not?

There are many Airplanes that fly, in spite of scientific theory...

[dtel]

When there is an overlap of bass sound from the front speakers and the subwoofer, you will get bloated and boomy bass.

 

That's what I was getting with the mains set to large, it sounded much better set to small, cleaner and better bass.   forte ll's ht

 

It probable has a lot to do with the different rooms also if it's better set small or large ? I always thought if a driver can't reproduce a sound it doesn't, ( subs may be different ) same for a tweeter if a recording goes to 30mhz and the tweeter can only get to 25mhz it just rolls off the rest, and it doesn't take much to hurt them ? But been wrong before

Edited April 24, 2015 by dtel

[Zen Traveler]

 

That's what I was getting with the mains set to large, it sounded much better set to small, cleaner and better bass.   forte ll's ht

 

It probable has a lot to do with the different rooms also if it's better set small or large ?

 

I think it has most to do with people's expectations and EQ ideas...Prior to understanding room dynamics, EQ and target curves I will admit to running my subs considerably hot enjoying the visceral sensations both felt and witnessed by crap shaking on the walls--When I learned the value of tight bass (felt and heard) that didn't mask nuances in other speakers, I reached Nirvana. 

Edited April 24, 2015 by tkdamerica

[gadgtfreek]

I eq my subs with XT32 dual sub eq. Seems to work well.

[Paducah Home Theater]

When there is an overlap of bass sound from the front speakers and the subwoofer, you will get bloated and boomy bass.

The placement of a sub in a room is the primary factor in receiving good bass sound. You cannot adjust the position of the front speakers and move them to the side or back.

The only reason it would do this is if the source material was recorded that way.

Plus, you're contradicting yourself. The alternative is to send this information to the subwoofer, which would be in a better location for stronger bass, and may have a 6-10 db boost on top of that. If anything, sending this information to the sub will make the bloated and boomy issue worse. Earlier I mentioned this happening with bass guitars, that's a good example.

 

Redirecting the bass to the subwoofer relieves the receiver/amplifier from having to work on reproducing the low frequencies and this greatly improves the headroom.

Totally agree with that.

Edited April 24, 2015 by MetropolisLakeOutfitters

[Quiet_Hollow]

It also bears mentioning, in addition to all the above, that a person can set their "crossover points" to whatever they want, but until they are measured at the listening position with a mic it's simply a rough idea.

 

In reality, the difference between the two is: setting of a filter point versus qualifying the acoustics. 

 

For example, the subwoofer at my place is "crossed over" at 35 Hz according to the LPF on my amp, but it's crossing over at the listening position at 95 Hz according to the mic. 

 

This is also where a lot of confusion between home theater and 2-ch arises, because setting a system as flat as possible, while a requirement for movies, often produces a lack-luster playback experience for typical music recordings.

[CECAA850]

This is also where a lot of confusion between home theater and 2-ch arises, because setting a system as flat as possible, while a requirement for movies, often produces a lack-luster playback experience for typical music recordings.

 

Setting it flat for movies is lackluster as well IMO.

[tromprof]

 

This is also where a lot of confusion between home theater and 2-ch arises, because setting a system as flat as possible, while a requirement for movies, often produces a lack-luster playback experience for typical music recordings.

 

Setting it flat for movies is lackluster as well IMO.

 

 

Beat me to it.

[garyrc]

Notion I:  Setting good front speakers to LARGE, with the sub(s) overlapping, and the AVR sub setting at LFE + Main will cause bloated or boomy sound.  Maybe, maybe not.  In my case, in my room, the answer is "not."  I do set my center (a Belle Klipsch) to SMALL, with a crossover of 40 Hz, though, to keep the damn voices (dialog) out of the damn sub.

 

Notion 2: Setting good front speakers to LARGE, with the sub(s) overlapping, and the AVR sub setting at LFE + Main will cause phase problems.  Maybe, maybe not.  In my case, the answer is "not."

 

Notion 3. Setting good front speakers to LARGE, with the sub(s) overlapping, and the AVR sub setting at LFE + Main will cause LFE to get into the main speakers, causing damage.  Probably not, from everything I've read.  Some AVRs might conceivably let LFE into the mains, and some might mix the LFE into the mains if the Sub setting is OFF ... so don't set the AVR sub setting to OFF.  For all of the AVRs & pre/pros I know or have read about, with the sub set to ON, true LFE goes out through the AVRs subwoofer output only, thus doesn't get into the mains.  The LFE + Main setting is a subwoofer setting, not a mains setting.   On the other hand, bass management bass, with some speakers set to LARGE, will let the low frequencies that are not part of LFE into the speakers set to LARGE. so some low organ notes, and the like, might distort or damage your speakers, if played very loudly.

 

It is true that frequency modulation distortion may be worse with a speaker cone pumping back and forth over a large distance, so, if that is audible from the front speakers, it may be better to set them on "small."  Then the sub will pump a little more, but the crossover prevents some FM distortion above it, since the tones being played by the mains will not be riding back and forth on the cone playing the tones below the crossover ... at least, so I understand.  It all depends on what you can hear, and whether or not it is objectionable.

 

But, as other people have said in their posts, I could be wrong.  So, read the manual carefully ... even though many AVR manuals are not very good.

Edited April 24, 2015 by garyrc

[derrickdj1]

Plus, you're contradicting yourself. The alternative is to send this information to the subwoofer, which would be in a better location for stronger bass, and may have a 6-10 db boost on top of that.

 

No contradiction if autocalibration is run the sub should not be 6-10 db hot without the avr having abnormal sub reading.  The guideline in the post are general guidelines that most experts agree with including Auddysee.  I have not waved on the fact that these are solid guideline in the last 4 years.  They are guideline that I share with new members consistently.  Bad bass is a setup or room problem and both need to be addressed.  Bass decay, reflections are a big factor as well as boosting a sub to discolor the midrange.  If one is having proplems, REW or Omnimic is a good direction to pursue.  Without measurement, it is all guess work for the most part.  At the end of the day everyone should set their system to what is pleasing to them.

 

Also, if the subwoofer bass system is adequate, there should be no need to use the setting SUB + Mains.  It adds nothing in a good system.  As I state early these guideline are based on science and I would love to see some scientific info supporting SUB + Mains or an abundance of data supporting no phase or cancellation problems.  Anecdotal experience may support a trend but, that is all it is until proven.

Edited April 25, 2015 by derrickdj1

[Paducah Home Theater]

 I would love to see some scientific info supporting SUB + Mains

 

 

The only time I've seen that be useful is with heavy metal, kick drums slam harder with LFE+Main.  I have no idea why or what this setting even does totally.  

[Paducah Home Theater]

 

No contradiction if autocalibration is run the sub should not be 6-10 db hot without the avr having abnormal sub reading. 

 

 

This is my biggest issue with it all, I purposely run things hot AFTER autocal as do many others.  While I like the sound of it during most movies, it makes for some awkward transitions sometimes.  I don't know how to get around that other than bump it down a little to avoid some of the things that often cause weird transition issues, such as low male voices, or keep things flat.  I totally agree that if you set things to be flat then some of the things I am mentioning make no sense.  All the issues I'm mentioning are with the subs purposely running hot in mind.  

Edited April 25, 2015 by MetropolisLakeOutfitters

[derrickdj1]

All the issues I'm mentioning are with the subs purposely running hot in mind.

 

That is why I got more wooferage.  I can get the shake and rumble without running things hot and causing an imbalance in the FR for movies.  I like having several preset so that I can easily switch between music mode and HT. 

 

I had a similar problem in a 5300 cu ft. room because the FR dropped in the low bass and I would run the subs hot.  Adding more subs did not effect the above 40 Hz FR but, brought the bottom end up.  Measurements help clarify the problem.

Edited April 25, 2015 by derrickdj1

[Scrappydue]

That is why I got more wooferage.  I can get the shake and rumble without running things hot and causing an imbalance in the FR for movies.  I like having several preset so that I can easily switch between music mode and HT. 

i don't think subs has anything to do with metro running his hot. he likes em hot. i'm with you derrick i don't run mine hot at all and i get a great experience. i run hot once in a while, but if the movie isn't non stop action, and some music starts playing with subs hot i immediately hate it. just sounds un natural to me. 

 

metro will get to come check mine out soon as he is coming up my way.