# The 80-120Hz hole?



## kwalikum

I've been reading up on satellite/sub crossover frequency including the recent thread regarding large vs. small amp settings, but I still seem to be missing something.

My understanding is frequencies above 80Hz start to be directional, and THX specifies an 80Hz crossover. I have a Sony STR DE475 and, while it doesn't say so specifically, it is generally assumed that the crossover for 'small' speakers is 80Hz, and I think I read somewhere than 'micro' might be 120Hz. All is well.

Here's my question:

Why are there so many satellite speakers that come nowhere near 80Hz (other than the obvious fact that the drivers are too small)? :huh:

I would understand if they all got poor reviews, but they don't. I've been looking at klipsch lately, and the quintets get great reviews while their specs say 120Hz:
http://www.klipsch.com/quintet-home-theater-system

Does this mean there is a hole in the 80Hz-120Hz range that nobody notices, or does everyone set their amp crossover at 120Hz, put the sub front and center, and hope they aren't distracted by sounds coming from it?

I've read all kinds of reasons why a person shouldn't buy small satellites, but I find it hard to understand why good companies get good reviews for these sorts of speakers.


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## tonyvdb

That "hole" does exist but its hard to hear sometimes due to room acoustics and reflection. In your description 120Hz isn't that bad many satellite speakers dont even come that close to 120Hz some like the Bose system dont even go below 350Hz meaning that the so called sub (not actually a sub at all) has to handle playing up much higher and even then only up to about 200Hz leaving an even bigger hole.
That 120Hz is not a brick wall rather a drop off. The same goes with the 80Hz on the sub it will go higher gradually dropping off so there will be some overlap although minimal


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## kwalikum

Thanks for that. Would you recommend setting the crossover higher to allow the sub to cover the hole and avoid sending lower frequencies to the satellites that they cannot handle anyway, or is a "whichever sounds better" listening test the best option? I don't have the satellites to test with at the moment, just worried if I do get them I'll end up with a compromise that I won't like.


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## tonyvdb

I think what sounds best to you is what is important. Dont always read too much into the numbers. that said its ideal to get the crossovers set so they are the same. I personally dont like speakers that cant play down to at least 80hz but if your set on the look of small speakers then setting the sub up to 120Hz wont really be all that bad.


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## astrallite

THX supposedly does require your speakers to handle a 80 Hz crossover seamlessly, although in reality given how many products (especially Klipsch) that seem THX Certified almost boggles the mind considering many of them employ tiny 3" drivers that even on the specification sheet will admit to be nowhere capable of an 80 Hz crossover.


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## chashint

astrallite said:


> THX supposedly does require your speakers to handle a 80 Hz crossover seamlessly, although in reality given how many products (especially Klipsch) that seem THX Certified almost boggles the mind considering many of them employ tiny 3" drivers that even on the specification sheet will admit to be nowhere capable of an 80 Hz crossover.


Just curious which Klipsch models are you specifically referring to?


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## kwalikum

chashint said:


> Just curious which Klipsch models are you specifically referring to?


http://www.klipsch.com/quintet-home-theater-system

Also their reference speakers in the cinema 6 package but they are no longer made

http://www.klipsch.com/rcx-3-center-speaker and http://www.klipsch.com/rsx-3-bookshelf-speaker


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## megageek

I have floorstanding towers all round so my amp is set at 60hz crossover. I find most subs get too boomy when playing higher frequency's. I would say set it where it sounds good. Too many variables to follow one opinion (thx).


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## MikeBiker

biach said:


> I have floorstanding towers all round so my amp is set at 60hz crossover. I find most subs get too boomy when playing higher frequency's. I would say set it where it sounds good. Too many variables to follow one opinion (thx).


I agree, set the cross over where it sounds good to the listener. 80 Hz is always a good place to start, but, depending upon many variables, it may have to be adjusted up or down to get the best sound for the listener.


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## ndurantz

Thanks for this thread. I have a set of Orb Mod 1s with a Mirage Omni 8 and have always been frustrated getting them to blend. I felt "locked down" to setting the x-over to 110 - 120. Doing so caused some parts of tracks to be "boomy" and some to be a little "thin." I will play around with things more freely now to see if I can get a better blend. 

I assume really the only way to avoid the "hole" is to go with full size towers that do a "fuller" spectrum?

Sent from my iPhone using HTShack


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## tonyvdb

Full sized towers would be ideal but many bookshelf speakers will go well below 80Hz and thats where any good sub will do just fine.


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## ndurantz

tonyvdb said:


> Full sized towers would be ideal but many bookshelf speakers will go well below 80Hz and thats where any good sub will do just fine.


Good point. I have thought stepping up to some smallish bookshelves would help out, but I also wonder if I am physically too close to the sub. It is sitting to the side of my desk and I am literally only a foot or two back from it as my desk is my main stereo setup.

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## tonyvdb

Still would be better than not using a sub at all. For music you rarely will get below 30Hz and that would still be just fine at that distance.


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## ndurantz

I will chalk it up to them not being blended correctly, then and fiddle around with my cross-over some. Thanks!

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## tonyvdb

If you have enough length on the cord for the sub try to place it in a coroner. that usually helps alot.


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## ndurantz

Not really sure that will help much in my current space as that would place the sub a significant distance from the mains. And the room is really an odd shape as it is a converted attic space. Still a good consideration, tho.

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## tonyvdb

Placement of the sub wont matter with regards to how it blends. Frequencies below 80Hz are non directional so you should not be able to "hear" where the bass is coming from.


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## ALMFamily

Angryht has a thread in the REW forum where he was moving around his sub to try to get a better response curve. I might suggest taking a look at it - pretty sure his best sub position was behind the main door. It might help to see the graphs in action to understand that the best position might not be one you have even thought about.


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## megageek

Moving the sub around the room is not about changing the direction you hear it from, its about changing the percieved volume of sound from a given position within a room. Sound bounces all over your room, including the bass. If you move the sub to another position, you have changed where the sound bounces and so where it is most loud in the room. A simple test we can all do is play something bass'y and walk around the room. You will hear the bass 'level' change as you move. Its not directional but it will change the percieved loudness. 

I heard of a simple test to find the sweet spot for your sub in any given room; put the sub in the listening position ( on the couch). Now move around the room while playing bass'y stuff and wherever you can hear the loudest bass is where you should put the sub. Give it a go!!


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## Timoteo

It's actually not about perceived loudness it's about which frequencies are getting canceled or boosted. These are called Peaks & Nulls. Don't worry about keeping the sub close to the mains. As long as the sub is playing below 100hz you shouldn't be able to pinpoint the subs location with your eyes closed. Yes that's because bass is "non-directional" as mentioned.

The previous post was describing the "bass crawl". Nobody should set. Sub in a room without doing this. It's the minimum that you should do when placing a sub. Placement is Paramount!! Proper placement can make a sub sound like a beast or a fart haha!


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## foofighter3

I would like to add that if you want to go with smaller speakers that only go down to 120hz+ you should pair them with a good quality small diameter sub as well. Stay in the 10"-8" range. You will be able to hear where your sub is when its set to 120hz cuttoff (only when its playing 80-120), but what you hear will sound good. 12" subs sound muddy at over 80hz because they vibrate so much, in a bad way, at those higher frequencies (common complaint about 12 inchers and people dont know why).

I would highly suggest an 8" sub or two to match with small speakers. If you get two you can play around with the locations until you semi dont hear where they are coming from. And set that cutoff to 120hz.

OR

Get two floor standers to replace 2 fronts that go to a low frequency (60hz or so). Set them to "large", set cutoff to 80hz. The floor standers will fill the 80-120 hole.

Hope this helps!


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## ndurantz

Great discussion. I actually got myself a pair of small bookshelves that I am going to try out with the sub to see if I can achieve a more "seamless" blend. I am using a Mirage Omni 8 & haven't tried moving it yet b/c I can't have the cord running across the floor. Any after-market wireless solutions/suggestions that could work?

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## Timoteo

Earthquake Sound makes a wireless sub adapter that you can hook up 2 subs to. There are others out there. I think RocketFish makes one too!


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## ndurantz

Timoteo said:


> Earthquake Sound makes a wireless sub adapter that you can hook up 2 subs to. There are others out there. I think RocketFish makes one too!


Thanks for the tip. I checked it out. Looks like the Rocketfish stuff are all amplified now & the Earthquake stuff is pretty expensive. However, it looks like both Aperion and Audioengine make something similar for around $150. Anyone had any experience with either of those set-ups?

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## turbo v6 camaro

foofighter3 said:


> I would like to add that if you want to go with smaller speakers that only go down to 120hz+ you should pair them with a good quality small diameter sub as well. Stay in the 10"-8" range. You will be able to hear where your sub is when its set to 120hz cuttoff (only when its playing 80-120), but what you hear will sound good. 12" subs sound muddy at over 80hz because they vibrate so much, in a bad way, at those higher frequencies (common complaint about 12 inchers and people dont know why).
> 
> I would highly suggest an 8" sub or two to match with small speakers. If you get two you can play around with the locations until you semi dont hear where they are coming from. And set that cutoff to 120hz.
> 
> OR
> 
> Get two floor standers to replace 2 fronts that go to a low frequency (60hz or so). Set them to "large", set cutoff to 80hz. The floor standers will fill the 80-120 hole.
> 
> Hope this helps!


I just did this, and thats how i set them up 

I have and older HK AVR 235 what do i want to set the sub for? it has many options like LFE and LFE+L&R 

i assume thats telling the reciver what source you have pluggin? I only have LFE so that what i selected. 

Then theres an option that i think controls what channle the BASS is played from, i set this on L&R 

is that correct? 

we have trouble hearing voices and the new floor standing speakers on the L&R really helped fill in a gap for the TSS-1200 system. 

its not fully installed yet waiting on my new chairs

i also though about removing the center channle


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## tonyvdb

foofighter3 said:


> I would like to add that if you want to go with smaller speakers that only go down to 120hz+ you should pair them with a good quality small diameter sub as well. Stay in the 10"-8" range. You will be able to hear where your sub is when its set to 120hz cuttoff (only when its playing 80-120), but what you hear will sound good. 12" subs sound muddy at over 80hz because they vibrate so much, in a bad way, at those higher frequencies (common complaint about 12 inchers and people dont know why).


That may be true for cheap subs but a good quality 12' or even 18" sub would not have that issue. You just need to spend the money on a good one.


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## jliedeka

I agree. A good sub should be able to cross at 100 or 120 Hz without a problem. It may not even by localizable at those frequencies. Opinions vary as to what frequency starts to be directional. I suspect that a poorer performing sub will sound directional at lower frequencies because its distortion products are audible and well into the directional range.

I have a Hsu sub. Hsu doesn't recommend a higher crossover than 80 Hz but I used mine up to 100Hz for a while with no directionality issues.

Jim


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## Dub King

Stereo subwoofers - as in a pair of subs each located next to one of your mains - is another option. It happens to be the what I use in my system. Think of stereo subs as speaker stands for bookshelf speakers, capable of turning them into full-range transducers. Regardless of the crossover point chosen, stereo imaging will remain intact... I'm using a 200Hz crossover because my subs are a dual 12" front-firing 'tower' arrangement. With a bookshelf speaker on top, they look suspiciously like the Wilson WATT Puppy.

The catch is you are limited in terms of placement options, and you need an AVR that outputs a stereo subwoofer signal, or else you need separates and DSP-based crossovers. However even with mono bass, the stereo sub arrangement allows for the higher crossover without compromising the soundstage the way a single corner-placed sub with a high crossover point would.



ndurantz said:


> Thanks for this thread. I have a set of Orb Mod 1s with a Mirage Omni 8 and have always been frustrated getting them to blend. I felt "locked down" to setting the x-over to 110 - 120. Doing so caused some parts of tracks to be "boomy" and some to be a little "thin." I will play around with things more freely now to see if I can get a better blend.
> 
> *I assume really the only way to avoid the "hole" is to go with full size towers that do a "fuller" spectrum?*
> 
> Sent from my iPhone using HTShack


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## 3dbinCanada

foofighter3 said:


> I would like to add that if you want to go with smaller speakers that only go down to 120hz+ you should pair them with a good quality small diameter sub as well. Stay in the 10"-8" range. You will be able to hear where your sub is when its set to 120hz cuttoff (only when its playing 80-120), but what you hear will sound good. 12" subs sound muddy at over 80hz because they vibrate so much, in a bad way, at those higher frequencies (common complaint about 12 inchers and people dont know why).


I respectfully disagree with this assertion. I can almost agree with this if cheap subs were used. However, subs made by reputable manufacturers such as SVS, HSU, Oultaw etc will not sound boomy above 80 Hz. They carefully design their drivers not to break up in the higher bass frequencies.


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## gdstupak

A 12" driver can be engineered to sound better reproducing lower sub bass frequencies or better reproducing higher bass frequencies. This from HSU's website:
"...a woofer optimized for low bass reproduction is not the best for mid to upper bass reproduction. A heavy cone is best for low bass, but that reduces the mid to upper bass efficiency. The MBM-12 MK2 woofer is optimized for mid to upper bass reproduction - a very light cone, low inductance voice coil, and a strong magnet yields extremely quick response with high efficiency. It demonstrates excellent micro-dynamics and an extremely wide dynamic range that no single subwoofer can provide."

I believe this is why the 12" woofers in my main speakers (JBL S312) sound ever so slightly better in that 80-120hz area than my old 15" subs and same for my new 18" subs. Last time I mentioned this, I got all kinds of suggestions about how my subs must have some problem.

Over the years, I have read several articles which suggest using 2 subs for the best integration with smaller sattelite speakers. One sub is optimized for mid bass, and the other sub is optimized for lower sub bass. A mid bass module can be bought through HSU... http://www.hsuresearch.com/products/mbm-12.html .


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## wpbpete

"...a woofer optimized for low bass reproduction is not the best for mid to upper bass reproduction. A heavy cone is best for low bass, but that reduces the mid to upper bass efficiency. The MBM-12 MK2 woofer is optimized for mid to upper bass reproduction - a very light cone, low inductance voice coil, and a strong magnet yields extremely quick response with high efficiency. It demonstrates excellent micro-dynamics and an extremely wide dynamic range that no single subwoofer can provide."



gdstupak said:


> Over the years, I have read several articles which suggest using 2 subs for the best integration with smaller sattelite speakers. One sub is optimized for mid bass, and the other sub is optimized for lower sub bass. A mid bass module can be bought through HSU....


Thank you for clarifying this :T When I saw this on the HSU site last week it didn't click with me. 

Would you hook up the subs so that one handles 150-80 and the other one 80 and below?
I'm thinking of placing the smaller sub under the cc set at 150hz and the larger one next to the seating area set at 80hz. Would this work? and how would you wire it? LFE to Y cable to subs? :dunno:

Denon 3801
Mirage MX 5.1 w/ MM6


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## gdstupak

wpbpete,
that is one way of connecting the 2 subs.

Here is another way if your smaller sub has 'high level input/output' speaker connections. With standard speaker wire, go from the AVR's main/front left and right speaker outputs, to the smaller subwoofer's 'high level input' left and right. Then with standard speaker wire, go from the smaller subwoofer's 'high level output' left and right, to the corresponding left and right main/front speaker. Then connect the bigger sub with the AVR's LFE output. 
With this type of connection, the AVR would be set up as if you were using bigger main speakers, you would set the main speaker crossover point to somewhere around 80hz (so 80hz and higher would be output to the main speakers (and to the smaller sub)... and the bigger sub would get the main speaker's signal that is below 80hz, plus it would get all of the LFE signal). (TIP: For the crossover setting knob that is located on the bigger sub, leave it set to it's highest setting, even if it goes all the way up to 150hz).

We can't hear your system, so we can't tell you which is the best way to connect everything. You are going to have to do it all and listen and decide for yourself which way sounds best to you.

Same thing with setting the crossover points and the sub's phase controls. That is going to take a lot of trial and error. Here are a few suggestions to help: (If you can't use the REW program that is available here at The Shack) buy an SPL meter, buy an audio test cd/dvd that plays test tones throughout the frequency range, and buy a few recordings of quality bass material to listen to (solo electric bass guitar, solo upright bass...).

Of course this is only beneficial if you can clearly hear that the smaller sub plays mid/high bass audio with greater fidelity than the bigger sub.


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## gdstupak

wpbpete said:


> I'm thinking of placing the smaller sub under the cc set at 150hz and the larger one next to the seating area set at 80hz.


Sub Placement:
The smaller sub would need to be placed front and center because you will 'hear' that sub playing the higher freq.
As far as placing the bigger sub next to the seating area, do you already know that that is where it sounds best? or are you asking if we think that is a good place for it?
If you don't know about doing the 'sub crawl' to find it's best sounding location: put the sub exactly in the main listener's position and play some bass audio over and over. Crawl around on the floor and listen for the best sound. Wherever you hear the best and most consistent bass audio is where you need to put the sub.


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## wpbpete

gdstupak, thanks again for the excellent information. 

you said
"With this type of connection, the AVR would be set up as if you were using bigger main speakers, you would set the main speaker crossover point to somewhere around 80hz (so 80hz and higher would be output to the main speakers (and to the smaller sub)... and the bigger sub would get the main speaker's signal that is below 80hz, plus it would get all of the LFE signal). (TIP: For the crossover setting knob that is located on the bigger sub, did you mean to say smaller? leave it set to it's highest setting, even if it goes all the way up to 150hz)"

My fear with this set-up is, that it seems like i'd be turning the MX's (or any sat system for that matter) into full spec speakers set to "small" on the avr. Doesn't that kinda defeat their goal of integration and sound quality? Realizing that i'd be setting the small sub's crossover to 150hz it still would not be producing (as it was meant to) anything under 80hz. 
Can't the small sub's crossover still be set to 150hz while using the LFE? Or does it not get those signals once the avr is set to small, It seems to, or are my ears deceiving me?
My goal is to allow the MM-6 to do what it's supossed to do and let the big sub pick up where the MM-6 leaves off. So settings would look something like this:

AVR set to small, 80hz
Y cable from LFE to both subs
MM6 (small sub) at 150hz
large sub bypassed or 60hz

Hopefully MM-6 will produce as close to it's full frequency response of 42hz-200hz. Of course if the LFE won't be sending it signals over 80hz then it's kinda of mood point LoL.....


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## gdstupak

wpbpete said:


> (TIP: For the crossover setting knob that is located on the bigger sub, did you mean to say smaller? leave it set to it's highest setting, even if it goes all the way up to 150hz)"
> .....


I meant what I wrote.
The LFE signal can contain content with freq up to 120hz. So you want the sub that is playing the LFE signal, to have a crossover high enough to play them.


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## wpbpete

gdstupak said:


> I meant what I wrote.
> The LFE signal can contain content with freq up to 120hz. So you want the sub that is playing the LFE signal, to have a crossover high enough to play them.


I agree, but shouldn't it be the small sub playing that signal? So the LFE does provide up signals higher than 80hz, I'm glad to hear that.


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## gdstupak

The LFE channel can contain frequencies above 80hz.
This part is just my opinion, I doubt these higher LFE channel frequencies are critical enough to necessitate needing a separate higher fidelity sub. Whereas frequencies 80-120hz engineered for the main speakers is probably audio best reproduced through higher fidelity speakers. I hope that made sense.


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## wpbpete

gdstupak said:


> The LFE channel can contain frequencies above 80hz.
> This part is just my opinion, I doubt these higher LFE channel frequencies are critical enough to necessitate needing a separate higher fidelity sub. Whereas frequencies 80-120hz engineered for the main speakers is probably audio best reproduced through higher fidelity speakers. I hope that made sense.


I agree, I guess that's the compromise we make with sat systems. I will be updating mine soon. Will post my system status then, thanks


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