Don't like direct-rad surrounds. Why do you? (1 Viewer)

[Ryan Tsang]

Ed: That's why surrounds in a theater are not distracting, because there are so many of them. and like Wayne says, they're far away.





Wayne: I have had (in a previous apartment) a rect room about 16x22 in which I tried a number of surr configs. couch was in the middle. Having direct rads in the rear 8 or 9 ft behind me left a hole in the side. Having them directly at the sides were too "beamy" The best that I've come up with is 4ft above head, 9ft away from me along side wall, crossing their axis behind my head. Therefore it was the best blend of imaging without being distracting. Bipoles in the same position is still more pleasant to me. THX style dipoles at direct sides created too much diffusion, like a pair of stereo speakers wired out of phase; don't like that either. That's how I came to prefer Bi/Omni poles.

 

[Kevin C Brown]

quote:THX specs call for dipoles on the sides, not direct radiators.

quote:Yeah...but not DTS or Dolby.

THX specs are for Dolby Pro Logic and Dolby Digital. (THX Surround EX? That is deconding of Dolby Digital THX Surrounds EX encoded soundtracks. THX specs wouldn't exist without Dolby Pro Logic or Dolby Digital.)

Wayne- When I had direct radiators as surrounds, I had them 7 ft away, and 2 ft behind me, tweeters 18 inches above my ears, pointed at me. And then I also bought into the hypothesis that with 7.1, 4 speakers back there rather than 2, that that would help with localization too. For me: didn't.

Some people suggest to point them straight ahead, or raise them to 2 - 3 ft above ear level. That, IMO, defeats the whole purpose of having direct radiators.

I.e., ever see an off-axis freq response plot of a direct radiator? You get comb filtering in the mids, and the highs are massively rolled off. Might as well use Bose for surrounds then.

Some people like the imaging of direct radiators as surrounds. That's cool. But for those that play tricks with the speakers' height and or direction to try to create a diffuse sound field with a speaker that isn't designed for it, why not just use a speaker that *is* designed to be diffuse but still can be properly positioned?

And for those of you who preach the mantra of any type of speaker but have never tried anything else, I say, try something else first, otherwise you know not of what you speak.

 

[Jerome Grate]

My preference is to be able to localize the surround as oppose to disbursing the sound in a wide field. I find the seperation between front and back is a more natural transition and well positioned speakers can create diffused sound and I think they sound better than sound directed to space between the speakers from bipolar. But it's all a matter of preference. If you don't like direct radiating speakers enjoy what you do. Finding out why other people dislike or like them I guess would boast your feelings towards direct radiating or not.

 

[CurtisSC]

quote:THX specs are for Dolby Pro Logic and Dolby Digital. (THX Surround EX? That is deconding of Dolby Digital THX Surrounds EX encoded soundtracks. THX specs wouldn't exist without Dolby Pro Logic or Dolby Digital.)

It is still a different spec...right?

 

[Greg-ST]

I like to hear whatever I'm playing coming out of the speaker(s) it was intended to come out of. If the sound was intended to pan from the front right to the rear left I want to hear that sound pan from the front right to the rear left, not from the front right to 'somewhere behind me'. In my setup the rear direct-rad's aren't distracting at all.

 

[Kevin C Brown]

Curtis- THX is not a "different spec" than Dolby Digital. In this particular case, THX is a unique set of criteria applied to equipment that is meant to (try to) perfectly replicate at home what you hear in a THX certified movie theater. That includes dipolar surround speakers. Dolby Digital soundtracks can be THX certified or not. Up to whoever is mastering the soundtrack. A lot more starting from this link:



http://www.thx.com/mod/techlib/speakers.html

 

[Jake S]

O.k., you're all right.....



I will say that it more has to do with the room, your seating in it, and the position of the speakers.



My room is small, my speakers (both sets of surrounds) are high ,and my seats are along 3 walls (obviously not the one where the tv is).....

I like multi-channel music but the tv plays a lot of movies too. I was never happy until I had switchable bi-pole/di-poles at the side and monopoles at the rear and a receiver that had presets to play either or /or both... now if I could only switch the sides from bi-pole to di-pole without getting up and doing it manually!



I will do the same type of thing with the B&W's I am considering, although I'm not quite sure of the models yet.

 

[Wayne A. Pflughaupt]

quote:

Some people suggest to point them straight ahead, or raise them to 2 - 3 ft above ear level. That, IMO, defeats the whole purpose of having direct radiators. I.e., ever see an off-axis freq response plot of a direct radiator?

Good point. Mine are 9 ft. high, 9 ft. away from the seating, and off-axis. Obviously there is some reduction of the highs and ample time for dispersion to make them less “localizable.” Hmm, maybe that’s why I like them!

I will say that my current home is the only place I’ve ever had a HT set up. If we ever get to sell this place and move, and encounter different circumstances – who knows, I may well find myself singing a different tune!

Regards,

Wayne A. Pflughaupt

 

[Andrew Pratt]

In my 6.1 config I have bipoles for my side speakers and a direct rad in the back. For my this gives me the ideal surround field as effects can be very directional if need be or softer for ambience. The 6th rear channel really adds a lot of depth to the rear sound stage

 

[Ryan Tsang]

quote:If you don't like direct radiating speakers enjoy what you do. Finding out why other people dislike or like them I guess would boast your feelings towards direct radiating or not.

Not at all. Maybe direct rad fans are doing something different that I don't know about and I could learn from it. I can't see myself buying anything other than bipoles and I'm curious as to why people would buy $$$ bookshelves/monitors for the rear. There has to be a reason.



I think overall this thread have been very civil and it's cool.

 

[Phil Iturralde]

Early on, the creator's of Dolby Digital 5.1 / (& 6.1) provided the following guidelines for the Recording Engineers and/or Mixing Studio Heads that were planning to jump on the 5.1 bandwagon. As you can see below, the Production Guideline helped them to identify what modifications they require to convert their existing Dolby Pro Logic Studios or if starting from scratch, ... what Dolby Labs recommended for them to Monitor/Mix 5.1 properly when they created the Movie Soundtrack Mix like the first DD-5.1 Movie 'Batman Returns', 1992.



1) 5.1-Channel Production Guidelines - Production Environment

quote:3.2.1 Front Speakers (pg. 24)

Multichannel sound systems add a center speaker to the Left/Right pair used in stereo systems. To promote good imaging, all three should be identical, just as conventional L and R stereo speakers must be matched. If all three cannot be the same model, the center speaker may be a smaller model from the same product line.



3.2.2 Surround Speakers (pg.25)

Whenever possible, use the same speakers all around to achieve uniformity. If this is not feasible, the surround speakers may be smaller than the front speakers but should maintain the same character; i.e. they might be smaller speakers from the same manufacturer.

With the advent of Multichannel Music, Dolby later provided the following Production Guidelines with the following Reference Monitors recommendation ...



2) 5.1-Channel Music Production Guidelines The 5.1-Channel Music Mixing Environment

quote:3.2 Monitoring pg. 16 & 17

3.2.1 Reference Monitors

Note: All five loudspeakers (L, R, C, LS, RS) should be identical.



One of the main differences between 5.1-channel setups for music and those for home theater playback is the type of speakers used for the surround positions. The goal of surround reproduction in the cinema (accomplished using multiple speaker arrays) is to provide surround playback to large audiences.



Surround effects are often very diffuse, ambient soundscapes. Dipole speakers are sometimes used in the home environment (rarely used in movie theatres) at the surround locations to help create the wide wash of sound created using an array of speakers in the cinema.



However, in 5.1-channel music production, as well as in films, the surrounds are sometimes used for distinct placement of featured performers. Accurate reproduction in this case requires the use of direct-firing speakers that match the overall characteristics of the front speakers. Use of matched direct radiator or monopole speakers in 5.1-channel music production is recommended for achieving the greatest control of level, timbre, and image location. Due to their dependence on null spot positioning, reflective front and rear listening room walls, and preference of a diffuse surround field, dipole speaker monitoring is not ideal for critical 5.1-channel music production.

To help consumer's, the following Dolby Labs FAQ recommends for the following question ...

quote:Frequently asked Questions about Dolby Digital[/url]

15. What kind of speakers should I get for an all-new Dolby Digital system? pg.6



The ideal Dolby Digital playback system would use identical full-range speakers for the left, center, right, and each surround channel. If this is impractical, be sure that the overall tonal characteristic, or timbre, of all the speakers is similar. This is equally important for both Dolby Surround Pro Logic and Dolby Digital playback.

Tom Nousaine was aware with the above HT 5.1 Guidelines when he established the HT Speaker Testing Standard for Sound & Vision. For the Surround location (see diagram) in his typical room, the standard was ...

quote:Sound delivered to the listener's ears from surround speakers will be reflected from room surfaces, so their response was averaged over a ±60° window with double weight given to the widest off-axis angles.

Since Dolby Digital 5.1 side and 6.1 rear center channels surround effects depend on the speakers high frequency (17 kHz to 20 kHz ±3 dB) extension to provide the distinct pin-point encoded effects specifically in size and distinct location, only direct-reflecting speakers were identified by the above Dolby Labs White Papers to give the Recording Mixer the tools to monitor the sound effects w/360-degree accuracy. Movie Sound effects like 5.1-Channel Music demanded the use of direct-firing speakers that match the overall characteristics of the front speakers. The recommended identical direct-firing speakers helped the Mixing Engineer to achieve the greatest control of level, timbre, and image location.



The above White Paper basically said, ...

quote:Due to their dependence on null spot positioning, reflective front and rear listening room walls, and preference of a diffuse surround field, dipole speaker monitoring is not ideal for critical 5.1-channel music production.

The above makes sense since a trumpet sound is not 6 feet wide diameter, as some dipole or bipolar speakers would reproduce.



Using Tom Nousaine Surround standard, speakers designed as di- or bipole rarely reach 15kHz @ the 'sweet spot', ... so not only is the encoded 5" diameter distinct 20 kHz effect is diffused to over 2-feet diameter but the 2nd and 3rd harmonics between the 15 kHz to 20 kHz are nearly non-existent or at the very least distant and finally based on the following on-line article**, ..." the fact that timing and phase cues are lost and the imaging specificity is lost., ... so much for distinct discreet 20 kHz surround effects.



** "Bipole, dipole, monopole?" by John R. Potis Jr.

quote: -- quoted below (from SMR HT Magazine - added: 2-5-01):



"Unfortunately, as in the classic "quantity VS quality" argument, all is not roses for the bi-pole. Creating the exacting, pin point image (the ability to close ones eyes while listening to music and point to each musician up on stage, both in terms of lateral spread and of front to back positioning on that stage) requires great precision on the part of the speaker. Timing and phase cues are everything. Sadly, with all the reflecting going on with bi-poles, many of these timing and phase cues are lost and the imaging specificity is lost."

So, since my blockbuster DD/DTS-5.1/6.1 DVD's are encoded using identical direct radiator speakers @ the Mixing/Monitoring 5.1/6.1-Channel Studio, ... it made sense to me to buy and setup my HT playback system(s) to reproduce that very same sonic speaker pattern, ... using the identical direct-radiators around me to recreate the encoded, pin point image(s), with discreet and seamless timing and phase cues accuracy so that my 360-degree surround effects environment in my HT/family room would sound glorious!!!



Phil

 

[JohnSmith]

And again I would avoid any bumfluff recommendations from the "experts" and try each for yourself. Only you can decide what is best IN YOUR ROOM, NOT DOLBY. If that is the case Bose must be great speakers?, because they say so.

Just because Dolby say so, doesn't make it the best choice without even trying the various types out.

Instead of just listing lots of techno babble compare the various types, when in reality your room swings it so far out the whole lot is rendered meanginless.
I'll betcha my system sounds far better than those with other speaker types of lesser speakers. But it must be "wrong" because Dolby say so.

As for Bi/Dipoles not reaching 15khz at the SS. What utter Bolxxx.

There was a blind test by a magazine where people choose dipoles for sides & surrounds over monopoles, again this shows Dolby recommendations are basically just interesting theory reading material.

If you pay too much attention to numbers you'll probably assume amp A is better than amp B just because of some superior technical matters (ie 3x more power), when in fact the lower powerered amp SOUNDS better (take Naim and Technics as two examples)

 

[Kevin C Brown]

quote:Using Tom Nousaine Surround standard, speakers designed as di- or bipole rarely reach 15kHz @ the 'sweet spot'.

Agreed: this is B.S. The whole point to a dipole, is that the integrated freq response all around the speaker is indeed flat. That is a THX requirement. And even though obviously not all dipoles are THX certified, *most* of them actually still adhere to this. Also turns out to be true for most bipoles and all omnipoles. Direct radiators only have a flat freq response *straight on* to the speaker. And I guarentee you, if you place direct radiators 2 - 3 ft above your head, you will have the high freqs rolled off. (But yes, as Wayne pointed out, that is one reason why the localization is improved. ) Remember how in the old Pro Logic days, that the signals to the surrounds were rolled off above 7 kHz? Yes, 7 kHz. DPL...

quote:Sadly, with all the reflecting going on with bi-poles, many of these timing and phase cues are lost and the imaging specificity is lost.

And this sounds like it is written by someone who, a) never actually has listened to well set up bipoles/omnipoles, and, b) doesn't understand the Haas effect.

The Haas effect is interesting: if the reflections are less than about 20 ms or so, the brain automatically lumps them in with the direct sound, and imaging is *not* affected. But to a lot of people, the overall presentation is enhanced.

Again, theory vs practice. Some of us have tried different speakers types, locations, and orientations. We ended up with what sounded the best to us in each of our respective systems because we compared ourselves. Some people however, argue from theory that a specific way is the only way because of what some expert says. Nope. If you have never tried any other type of speaker than what you feel is the best, then I say you are very likely shortchanging yourself in terms of at least being able to compare the soundfields from your own direct experience, and possibly from not having the best setup that you could because you might be missing out on something you'd prefer even more that what you have now.

Ryan- I have a theory why there are so many direct radiators used for surrounds.

Because a lot of speaker manufacturers *don't* offer dipole or bipole surrounds, so if you want to stick with the same company all around, you don't have any choice for the surrounds but monopoles. That's my *theory* for the day!

 

[Lewis Besze]

quote:Instead of just listing lots of techno babble compare the various types, when in reality your room swings it so far out the whole lot is rendered meanginless. I'll betcha my system sounds far better than those with other speaker types of lesser speakers. But it must be "wrong" because Dolby say so.

I think it's safe to say that Dolby is beyond the "trial and error" method by now as they the one who "wrote the book" on that.They only make a recommendation not a definite "law",so one can adopt it or not,it' up to you. But to dismiss it as a "techno babble" is just wrong.

 

[Lewis Besze]

quote:Agreed: this is B.S. The whole point to a dipole, is that the integrated freq response all around the speaker is indeed flat.

TN actually does his own measurments, do you?He also explains the way attains his results,perhaps his method is different then THX's hence his findings ?

 

[Lewis Besze]

quote:Again, theory vs practice. Some of us have tried different speakers types, locations, and orientations. We ended up with what sounded the best to us in each of our respective systems because we compared ourselves. Some people however, argue from theory that a specific way is the only way because of what some expert says. Nope.

Nope is right. I did all the trials and different speakers types and placements in two different homes,and both times I ended up with monopoles as my preffered set up.So from where I sit they were right.[the experts]

quote:Ryan- I have a theory why there are so many direct radiators used for surrounds. Because a lot of speaker manufacturers *don't* offer dipole or bipole surrounds, so if you want to stick with the same company all around, you don't have any choice for the surrounds but monopoles. That's my *theory* for the day!

The ones that don't make bi/dipoles are the ones that don't care for them in the first place,based on what they think is "good sounding" speaker.

quote:Sadly, with all the reflecting going on with bi-poles, many of these timing and phase cues are lost and the imaging specificity is lost.

quote:And this sounds like it is written by someone who, a) never actually has listened to well set up bipoles/omnipoles, and, b) doesn't understand the Haas effect.

I agree with the first quote,based on what I've heard,iterestingly you bringing up a theory here why this shouldn't be[Haas effect]yet you argue just a few lines above that theory is only that and reality what matters.

It seems that my reality matches some of the theories presented here.

 

[Kevin C Brown]

Lewis- The Haas Effect, which is indeed a theory, explains the practical observations that the reflections from a bipolar/omnipolar speaker don't destroy the imaging capability of a speaker of that type. Oops, up to 50 ms:

[url=http://www.sonicmagician.com/articl...ass_effect.html]http://www.sonicmagician.com/articl...ass_effect.html[/url]

quote:and both times I ended up with monopoles as my preffered set up.So from where I sit they were right.[the experts]

So I guess the THX people are just all completely out to lunch, aay? Paradigm, B&W, Mirage, Def Tech, Polk, Wharfedale, etc, too? (All of which offer dipoles and/or bipoles for surround sound use.)

But I do give you credit. You have tried other types, and that is all I'm getting after. You speak from experience. A lot of people do. And some don't. If a person has any doubt? Then they should try their own experiments.

 

[Jake S]

I reiterate, use both and switch back and forth between them, if neccesary, as your personal tastes and preferances dictate. Placement of the speakers, and the furniture are going to matter as will the room itself.

I often find a disconnect between front and rear direct radiators when sounds are moving in movie soundtracks, however, I often attribute some of this to the poor placement of the direct radiators.

In 7.1 , when I have been setting up direct radiators the problem is often due to where the side surrounds are placed and how much attention they draw to themselves . Usually the room or the decor, or the wife have a lot to do with dictating speaker placement options. For those of you who can build a room knowing what speakers and where to place them , and room treatments and appropriate seating locations, I envy you, it is just that the majortiy of my system designs have soom of these "variables" already established.....I often tell clients not to decide on speakers independant of room design and furniture layout because these may severly impact placement and speaker selection.

God forbid you have to include interior decorators in your decision.

 

[Tim Hoover]

quote:So I guess the THX people are just all completely out to lunch, aay?

Well, Kevin, if you prefer dipoles or bipoles, you could suggest that the fine folks at Dolby Labs are out to lunch. It seems to come down to personal preference and basic audio values. Perhaps THX feels that a more dispersed rear soundfield is desirable, and thus suggested speakers to enable this. OTOH, Dolby may feel that the rear soundfield should be more precisely defined, and this led them to specify what they did...

 

[MikeH1]

I use the Mirage OM - R2 bipoles for rears and think they do a great job. With 2 angled tweeters, a lot of my surround comes from reflections off the very back wall since these are mounted on the side walls. It creates a huge soundstage. Its nothing like the pin point imaging that some desire, I think for rears (and especially movies) this works well. When listening to DVD Audio I could get more accurate if I moved them back a few more feet then the front tweeter would give me what I *think* would be better for music. But I needed to go with a happy medium and positioned the speakers accordingly.