2.2 audio set up. any suggestions?

[ilovetoast]

Hello, I'm looking to build a 2.2 audio system for a 19' by 12' room that opens up to other rooms. My budget is 2-2.5k canadian for an integrated amp, 2 subs, and 2 loudspeakers, new or used. anybody have any recommendations, it will help quite a bit.

thank you.

[Mr Peabody]

Any more criteria to help narrow the field? Bookshelf or floorstanding speakers or does it matter? Music or both music and video? Listening style, genre of music? Sources, ie. CD, turntable, streaming?

You may be able to get separates on an integrated budget, www.emotiva.com Their stereo preamp also has a dedicated sub out with crossover. I tend to favor integrated amps by Arcam & Creek. Rotel and NAD are pretty good bets as well.

Have you thought about speakers with an amplified bass module already built in like the Definitve Technology? There so many ways to go so I will wait to see if you can help give us more of a direction.

Welcome to AR

[EYEdROP]

Describe what a good soundsystem would sound like to you. Describe how you like the bass, guitar, singer, drums, cymbals to sound.

[Feanor]

Hello, I'm looking to build a 2.2 audio system for a 19' by 12' room that opens up to other rooms. My budget is 2-2.5k canadian for an integrated amp, 2 subs, and 2 loudspeakers, new or used. anybody have any recommendations, it will help quite a bit.

thank you.

Welcome to AR Forums, Toast.

It will certainly be possible to set up a very decent 2.1 system on a 12' x 19' foot room.

The type of music you listen to and how loud you like it are big considerations: maybe you could tell us about these things.

Why do you want subs? There are three major reasons to consider one sub instead of two under your circumstances:

• Sound is uni-directional below about 80 Hz, i.e. mono or stereo makes really no difference
• Low frequency transducers are prone to cause room effects, specifically resonance nodes at certain frequencies; two speakers exacerbates this problem
• With you budget, the extra cost of a 2nd, decent sub is money that could better be spent on other components.

[audio amateur]

I believe 2 subs would help smooth the overall response

[JoeE SP9]

They do. Placed asymmetrically they help smooth each others response. Two is definitely better than one.

[Sir Terrence the Terrible]

Gentlemen,
Bass is omni-directional below 80hz, and two subs smoothes the response of two or more seats, not the entire room.

There is no such things as a 2.2 system. It is a 2.1 system with two subs handling the same information, or it is 2.0 with subs handling the low bass content (via crossovers in the subs) in each channel. Any pre-pro that offers two sub outputs is actually sending out the same mono signal to two outputs.

[Mr Peabody]

Hmmmm.... I always thought ".0" meant "no sub", as in 5.0. And ".1" represented the LFE, as in 5.1. I took 2.2 to mean stereo with two subs. You West coast guys always trying to be different.

The asymmetrical thing is new to me, I believe I first heard about it from another forum. These guys do some wild stuff with subs. Anyway as it was described it sounded like it ssmoothed the entire response. The second sub filling in dips left by the first. As they were talking about sub concepts I hadn't heard of before i figured they may know what they were talking about but who knows. One guy had a sub near to the ceiling. Some rave about those infinite baffle in-wall designs.

[Feanor]

Hmmmm.... I always thought ".0" meant "no sub", as in 5.0. And ".1" represented the LFE, as in 5.1. I took 2.2 to mean stereo with two subs. You West coast guys always trying to be different.

The asymmetrical thing is new to me, I believe I first heard about it from another forum. These guys do some wild stuff with subs. Anyway as it was described it sounded like it ssmoothed the entire response. The second sub filling in dips left by the first. As they were talking about sub concepts I hadn't heard of before i figured they may know what they were talking about but who knows. One guy had a sub near to the ceiling. Some rave about those infinite baffle in-wall designs.

Yes, I suspect that with careful positioning, (and an obliging room), you might be able to set up sub #2 to cancel the reinforcement nodes of sub #1. However also I suspect it would be easier (and cheaper) to carefully place just the one sub and, if necessary, apply some equalization.

The other reason offered for two subs is that the original recording might have out-of-phase bass information that can only be reproduced by two subs. However this ignores that fact the combining the out-of-phase signals electronically will achieve the effect more reliably than than trying to do so accoustically in the room when the frequency is below 80 Hz.

I feel bottom line for our new poster, with his $2k budget, is to go with one, properly set up, sub. At least the money saved could be spent to upgrade other components.

[IRG]

I would think in a 19 x 12 room that one sub and 2 (maybe more full range) speakers should be sufficient to fill the room. 2 subs in a space that size would seem overkill, but it does open to another room, and I don't know what the celing height is either. I would agree that more should be spent on the other components. You could always add a 2nd sub later if needed.

[Sir Terrence the Terrible]

Hmmmm.... I always thought ".0" meant "no sub", as in 5.0. And ".1" represented the LFE, as in 5.1. I took 2.2 to mean stereo with two subs. You West coast guys always trying to be different.

LOLOL!! Well, you are right. Officially, to the left of the dot is your discrete channels, and to the right of the dot is your limited range channels. So 2.2 would be two stereo channels with two stereo subs, which does not exist on any audio or video medium I can think of. Folks(trying to differentiate their systems) these days are not using this as it properly should, so they are using the right of the dot to show how many subs they use, not how many limited channels.

The asymmetrical thing is new to me, I believe I first heard about it from another forum. These guys do some wild stuff with subs. Anyway as it was described it sounded like it ssmoothed the entire response. The second sub filling in dips left by the first. As they were talking about sub concepts I hadn't heard of before i figured they may know what they were talking about but who knows. One guy had a sub near to the ceiling. Some rave about those infinite baffle in-wall designs.

Sounds like Hometheatershack.com. Two subs placed in the two front corners(in a rectangular room only) with smooth the response of a front row of seats, but will make it worse over a back row of seats closest to the rear wall. However the seats in the middle of the room will not benefit from the smoothed output, as they sit in the middle of the room in a low pressure area.

I think infinite baffle in wall systems are completely unnecessary unless your viewing room is absolutely huge, and even then it is not needed. Does anyone really need a flat in room response to 10hz? Really, aside from the infrasonics of a very few movies and organ recordings(even those have next to nothing at 10hz) there is nothing down there worth reproducing. I think this is pissing contest area myself.

[Sir Terrence the Terrible]

Yes, I suspect that with careful positioning, (and an obliging room), you might be able to set up sub #2 to cancel the reinforcement nodes of sub #1. However also I suspect it would be easier (and cheaper) to carefully place just the one sub and, if necessary, apply some equalization.

For a sole listener in this size room, this is correct.

[quoteThe other reason offered for two subs is that the original recording might have out-of-phase bass information that can only be reproduced by two subs. However this ignores that fact the combining the out-of-phase signals electronically will achieve the effect more reliably than than trying to do so accoustically in the room when the frequency is below 80 Hz.[/quote]

Even with out of phase bass information below 80hz, the wavelengths are too long to perceive any "stereo" effect. Testing has proven this.

I feel bottom line for our new poster, with his $2k budget, is to go with one, properly set up, sub. At least the money saved could be spent to upgrade other components.

Agreed!

[Ajani]

Hello, I'm looking to build a 2.2 audio system for a 19' by 12' room that opens up to other rooms. My budget is 2-2.5k canadian for an integrated amp, 2 subs, and 2 loudspeakers, new or used. anybody have any recommendations, it will help quite a bit.

thank you.

Since you're looking for an Integrated Amp then I assume your priority is music (and not HT), so I'd suggest keeping it simple and buying and Integrated Amp and a pair of Floorstanding Speakers (and forget the subs)...

Near your price range (new) I'd opt for a Rotel RA-1520 Integrated Amp with either Revel Concerta F12 Towers or Monitor Audio RX8 Towers... However, like with all audio, you need to audition these items yourself...

[E-Stat]

Even with out of phase bass information below 80hz, the wavelengths are too long to perceive any "stereo" effect. Testing has proven this.

The trick, however, is assuring that there is little output at that frequency. With commonly found 12 db/octave crossovers you must set them far below 80 hz to achieve that goal to ensure a lack of localization.

rw

[Sir Terrence the Terrible]

The trick, however, is assuring that there is little output at that frequency. With commonly found 12 db/octave crossovers you must set them far below 80 hz to achieve that goal to ensure a lack of localization.

rw

It seems that the industry has already chosen steeper crossover slopes than 12db/per octave. 24db/per octave seems to the dominate choice, at least from what I have seen.

[Feanor]

The trick, however, is assuring that there is little output at that frequency. With commonly found 12 db/octave crossovers you must set them far below 80 hz to achieve that goal to ensure a lack of localization.

rw

Do you really think far below? (Assuming the 80 Hz is, indeed, the no-localization point, and I'd guess you meant "ensure localization" rather than lack of it).

I understand that shallower slope means more mono above 80 Hz from the single sub, but I wonder if this is significant, especially given you get more stereo below 80 Hz from you mains. But I do generally believe in steeper crossover slopes since it reduces driver output interactions including phase effects and "lobing".

[audio amateur]

As E-Stat said, if you have a shallow slope (12dB octave), then you'll have to set the sub's low pass crossover well below that point in order to get real attenuation at the 80Hz mark and above.

[E-Stat]

Do you really think far below?

Just for grins, I reconfigured my two subs in the HT. I set the crossovers as low as they would go (50 hz) and the high pass on the receiver nearby (60 hz). Since my room mode effects exist at higher frequencies, the result is less linear although I was able to remove the EQ. Just today, I used a test CD to determine how much output they have at various frequencies when playing alone. I could begin hearing output at 120 hz, with significant response at 80 hz. As Sir T indicated, it does seem that the preponderance of modern subs do offer 24 db/octave slopes which would help. Mine are slightly oven ten years old. There are a few, however, like Velodyne, M-L, and REL who either don't or specify nearly flat response out to 100 or 120 hz.

(Assuming the 80 Hz is, indeed, the no-localization point, and I'd guess you meant "ensure localization" rather than lack of it).

As for me I want to eliminate localization of a subwoofer. I want to close my eyes and not be able to immediately point to where the sub is located in the room - which is what I've heard in a number of systems.

I understand that shallower slope means more mono above 80 Hz from the single sub, but I wonder if this is significant, especially given you get more stereo below 80 Hz from you mains.

My concern really doesn't involve stereo effects - simply eliminating the notion of hearing the bass emanating from a readily identifiable source.

rw

[Sir Terrence the Terrible]

Do you really think far below? (Assuming the 80 Hz is, indeed, the no-localization point, and I'd guess you meant "ensure localization" rather than lack of it).

In actuality 80hz is the threshold were nobody can hear stereo or directional information when testing was done on this. The threshold of directional detection(where the first person could ascertain directionality) was closer to 150hz, and where everyone could detect direction stood at 160hz. This was with pure sine waves and a exceptionally low distortion subwoofer to keep higher harmonics from contaminating the test.

I understand that shallower slope means more mono above 80 Hz from the single sub, but I wonder if this is significant, especially given you get more stereo below 80 Hz from you mains. But I do generally believe in steeper crossover slopes since it reduces driver output interactions including phase effects and "lobing".

In that bold part, it should read LESS stereo below 80hz from your mains.

Here's the rub. If I set my single sub woofer exactly in between two main speakers, and used a 12db/per octave low pass filter set at 80hz and did a frequency sweep, would I really hear more directionality an octave up with the less steeper slope? Probably not. If the sub sits exactly where bass would image between two loudspeakers, you would not be able to tell the sub output from the main output at 160hz. Now if I were to place the sub in a corner, and do the same experiment, you would probably be able to tell which output is which because the direction of output at 160hz would differ between the sub and the mains. Since "timing" plays a huge role in direction detection, it is the offset of the output of the sub and mains that give the sub direction away an octave up. As you go up in frequency, you will be able to hear the shift from the corner to the middle between the loudspeakers. When the sub is exactly in between the speakers, there is no shift in the output. So while the slope does play a role in detection, sub woofer placement plays an even bigger role in this example.

[E-Stat]

So while the slope does play a role in detection, sub woofer placement plays an even bigger role in this example.

Given that the suggestion given by many is to locate a sub in a room corner, I would emphatically agree when only one is involved.

rw

[Sir Terrence the Terrible]

Given that the suggestion given by many is to locate a sub in a room corner, I would emphatically agree when only one is involved.

rw

There is a reasons you should locate your sub in a corner.

A). It is the place where you get the flattest response from your sub.
B). You get an additional 6-9db boost without turning up the volume. You can use this to lower distortion by turning the volume on the sub down.
C) The crossover point for almost all pre-pros and recievers use steep 24db/per octave slopes, so by the time you get to the frequency of localization, there is very little output coming from the sub.

Yes the corner excites all of the rooms modes and nodes, but modes are easier to equalize than late arriving reflections are. We can equalize a specific event, but we cannot equalize time related events such as reflections.

The reason to locate the sub in the center of the room

In small rooms modes can pile up on each other, causing build up that exceeds the correction that most eq's can address. In this case, locating the sub out of a high pressure zone will actually keep those resonances from building up to such high levels they cannot be equalized. I have a 7.1 system in a 12x16ft room, and this is the problem with this room. With corner placement, I had three modes very close to each other that created a broadband boost my EQ's could not notch out. I moved the sub to the center of the room, and I had one notch that was correctable, and several smaller ripples(short reflections) of which only one could be tackled with EQ. What was left was treated by moving the viewing seat a bit closer to the sub, which made those ripples in the frequency response disappear. With the sub located at the center of the room, its output fell higher up in frequency than when it was located at the corner, so I had to create a room curve to keep the sub's response up below 35hz. When all is said and done, you have a 20-80hz response with only a 2db deviation from flat between 30 and 40hz. This I can live with.

[audio amateur]

-Corner placement is where you get the flattest response from your sub.

-Yes the corner excites all of the rooms modes and nodes

Aren't these two in contradiction with each other? Or are you implying in the first case that you have used EQ?
(I edited your post slightly for clarification purposes)

[Sir Terrence the Terrible]

Aren't these two in contradiction with each other? Or are you implying in the first case that you have used EQ?
(I edited your post slightly for clarification purposes)

Not really. In most rooms from 20-80hz you will get a couple of very loud modes, but when you equalize them out, you will get a much flatter frequency response than if you do not excite them. These modes are usually spaced apart enough to be notched out with parametric EQ.

If you use a center location, you will excite modes and nodes minimally, but later arriving reflected signals will cause more ripples in the response that are looser, and more broadband. These cannot be tamed with eq alone(or if at all) because they are time based issues, not mode or node based ones. This can only be corrected by sitting so close to the sub, that you effectively remove the room out of the equation. Even then their influence is not always completely removed unless the sub sits in free space.

I believe that EQ should be used on frequencies below 80hz, as acoustical solutions are pretty ineffective at these frequencies, and sometimes seating placement does not help that much either.

[E-Stat]

There is a reasons you should locate your sub in a corner...etc, etc...

They are well known starting points. I've experimented quite a bit with sub placement over the past decade. As with your room example, it is not always optimum if balanced output and seamless integration is what you seek. Speaking of center mounted subs...

BTW, call me crazy but I saw Avatar again today at a third different IMAX closer to me. Although they played things at uncomfortable levels (peaks > 96 db), it was the cleanest sound I've heard at a theater. I suspect part of that is because the theater is barely a year old. The spatial effects were much more realistic. There is a scene where Jake is with Neytiri and shoots an arrow. You clearly hear the launch and the flight path of the arrow whiz past you from front right to left rear. There was more inner detail to be found. Some of the explosions had a very realistic concussive effect. Ultra tight slam. All in all quite good.

rw

[audio amateur]

call me crazy
rw

A little, yes