1. Join Now

    AVForums.com uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

di-polar v's bi-polar

Discussion in 'Home Cinema Speakers' started by eman, Nov 2, 2001.

  1. eman

    eman
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Hi all,
    Wondering if any of you AV home cinema fans can give me some feedback to using any of the two types of speakers and experiences gained as a consequence.
    I have a denon 3801(why did they do that to us, brought mine 6weeks before 3802 came out!?) and tannoy M series speakers, plus a paradigm PDR10 sub.
    Am looking to upgrade these surround speakers with 7 instead of 5 and intend using di-polars at side of room.
    Finally has anyone sourced paradigm speakers other than from richersounds?

    In waiting anticipation to spin up T2 on me system
    Laterz
     
  2. Gary Lightfoot

    Gary Lightfoot
    Well-known Member

    Joined:
    Apr 6, 2001
    Messages:
    12,140
    Products Owned:
    0
    Products Wanted:
    1
    Trophy Points:
    136
    Location:
    Surrey. UK.
    Ratings:
    +1,953
    Hi eman.

    I had a similar quandry myself - bipoles or direct radiators?? I have a 3802.

    I bought some Eltax HT2s from Richer Sounds (now only £80), just so that I could experiment with them.

    I have 4 AE Aegis Ones which I initialy used for my rears, but I had to angle the back surrounds down because the sound they produced sounded as if it was coming from the front. This was easily demonstrated using the test tone.

    I Then tried the bipoles as the side surrounds, but I didn't like them, as the sound seemed too vague. It's a personal preference I think, but I prefer direct radiators at the sides, so I still have the Aegis 1s as the side surrounds.

    I then tried the HT2s at the rear. I personally found them to give a much better rear soundfield, and they don't need angling down as the sound isn't being fired forward.

    Buy one pair of bipoles (I think they will sound better than di-poles because the speakers are in pahse and produce more bass), and try them Like I did. See what is best for you.

    I think the way I have my speakers now follows a logical pattern - when DPL first came out, di/bi-poles were reccommended as the effects speakers because of the type of sound field they produce from a mono matrixed source.

    When 5.1 came out, direct radiators seemed to be the reccomendation because the rear soundfield was now full range stereo.

    With 7.1, we basically have 5.1 with two extra speakers. So use your existing 5.1 as it is - direct radiators all round. As the new rear surrounds are a mono matrixed derived sound like DPL (or mono discrete, but not much different sound wise), then it seems to me that the same rules as before apply - use bipoes to disperse the sound in the same way they did for DPL.

    It's just my opinion of course, based on my own experience, and you may have different preferences, but if you need another pair of speakers anyway, you can't go wrong with the HT2s at the current price of only £80. :)

    HTH

    Gary.
     
  3. eman

    eman
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Hi Gary,

    Thanks for you insight into good methods for discovering possibilities of bi-polar.

    The thing is when writing di-polar, did not mean direct radiating but di-polar being out of phase surround speakers as oppose to in phase bi-polar.

    This is probably why you encountered problems when placing your bipolars to the side since they radiate sound together in both directions and hence give off a percieved source image of sound.

    This is the idea of dipolar, where each side of surround speaker is out of phase hence cancelling out eaxchother producing a less point of source sound. These are a basic requirement of THX surround speakers.

    Am happy to hear you confirm though that the bipolars worked well for oyur rears, this is one thing I was concerned with.

    My idea is to use dipolars at side and use both bipolar and direct radiators for rear. Supposedly the preferred layout is to use the bipolars high up and pointing down in the corners and to have the direct radiators producing the matrixed centre rear channel at a more ear level listen positoining.

    Any more comments welcome from all.

    Rgds
    E
     
  4. Gary Lightfoot

    Gary Lightfoot
    Well-known Member

    Joined:
    Apr 6, 2001
    Messages:
    12,140
    Products Owned:
    0
    Products Wanted:
    1
    Trophy Points:
    136
    Location:
    Surrey. UK.
    Ratings:
    +1,953
    I think that bipoles are preferable to dipoles due to there being more bass. I guess it's a personal thing. When I refered to 'direct radiators' I mean of course normal speakers. Just to clear up any confusion there. :)

    I didn't like the bi-poles at the sides because they didn't give a perceived source of sound. They were too vague. I prefer normal speakers in the 5.1 configuration, with bi-poles for the rears in 7.1.

    How are you going to use both direct radiators and bipolar speakers for the rear? You going to use 4 speakers at the rear, and two at the sides? Or di-poles all round?

    Or do you mean tri-poles??

    Gary.
     
  5. Reiner

    Reiner
    Active Member

    Joined:
    Jul 16, 2000
    Messages:
    3,315
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    61
    Location:
    Germany
    Ratings:
    +13
    The Denon amps (3801 and higher) have rear speaker switching facility, so you could indeed connect 6 speakers at the back, e.g. 4 di/bipolar for 7.1 and 2 direct radiating (normal, monopole) speakers for 5.1 music.
     
  6. Gary Lightfoot

    Gary Lightfoot
    Well-known Member

    Joined:
    Apr 6, 2001
    Messages:
    12,140
    Products Owned:
    0
    Products Wanted:
    1
    Trophy Points:
    136
    Location:
    Surrey. UK.
    Ratings:
    +1,953
    Oh yes, I forgot about that. I didn't realise that was what he meant to do...

    I was going to do a similar thing myself, but with bipoles and direct radiators as the alternative ones, and just select which ones I wanted depending on the source. i.e dpl or 5.1

    As it turns out, I didn't like the bipoles at the sides anyway, so it ceased to be an option.

    Gary.
     
  7. Ian J

    Ian J
    Banned

    Joined:
    Aug 6, 2001
    Messages:
    25,529
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Ratings:
    +4,906
    Whilst direct radiating speakers may be preferable at the rear most people do not live in American style huge rooms and they have their settee pushed up against the rear wall.

    I feel that in practice bipoles are more practical in these circumstances as the sound from direct radiating speakers a couple of feet away from your ears is overpowering.

    Ian
     
  8. Gary Lightfoot

    Gary Lightfoot
    Well-known Member

    Joined:
    Apr 6, 2001
    Messages:
    12,140
    Products Owned:
    0
    Products Wanted:
    1
    Trophy Points:
    136
    Location:
    Surrey. UK.
    Ratings:
    +1,953
    Hi Ian,

    I tried the bipoles in my lounge originaly (5.1 set-up), where my sofa is pushed up against the wall. The speakers are about 4ft from my ears, on stands, facing directly towards the sofa. The backs are against the side walls.

    At lower volumes, there's not much difference, but at higher volumes there was a slight difference in the sound.

    I think that as they were more or less in a corner, the rear firing half of the speaker was bouncing of the wall and traveling along the rear wall in much the same way as a direct radiating speaker.

    I honestly couldn't say one was much better than the other.

    Fortunately, I can say I notice a bigger difference in a 7.1 set-up using them as the rear center channel.

    Gary.
     
  9. Matt F

    Matt F
    Active Member

    Joined:
    Jul 18, 2000
    Messages:
    900
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    21
    Location:
    Chester, UK
    Ratings:
    +4
    I think this is a bit of a generalisation - a good pair of dipoles such as KEF TDM34DS certainly don't have a lack of bass - far from it.

    Having owned both bi and di-poles I'd say the latter are vastly superior but there are a couple of caveats - they cost a lot (£699 for the KEFs) and they aren't easy to drive - you need some real power to get the best from them.

    The difference sound-wise between the two is - the bi-poles spread the sound around the room quite well whereas the di-poles disappear altogether so that it's very difficult to pin-point where the sound is coming from - just what you want for movies. Personally I think they also work well for 5 channel music as long as you're getting ambient effects (and not instruments popping up out of nowhere) in the rear channels but that's another argument.

    So, in conclusion, di-poles such as the KEF TDM34s are brilliant (and, yes, I own a pair), but they're bloody expensive and you need a lot of power to do them justice.

    As for the original question - I would say that bi, di or tri poles on the sides with direct radiators on the back wall would be a good shout.

    Matt.
     
  10. Nic Rhodes

    Nic Rhodes
    Well-known Member

    Joined:
    Mar 23, 2001
    Messages:
    17,133
    Products Owned:
    0
    Products Wanted:
    1
    Trophy Points:
    133
    Location:
    Cumbria
    Ratings:
    +1,277
    I'm with Matt on this one. Dipoles do / can have bass.

    I am not a fan of bipolar speakers. I have written elsewhere on this today already, for me all experriment were inconclusive and did yield good results. Dipoles did.

    5.1 Music use direct radiators
    7.1 Music use direct radiators

    5.1 Movies use dipoles (rear / sides) even for digital sources
    7.1 Movies use dipoles for sides and rears can be either dipole or direct radiators

    I therefore use all dipoles for Movies (7.1) and switch direct radiators in for music (7.1) as this gives a little extra definition and focus.

    All the debate seems to be over types of loudspeakers and I found greater differences between diferent qualities of speakers (cheapo speakers like we used to use for PL are no longer applicable).

    THX Ultra2 I think have it right now with dipoles at the side and direct radiators at rears.

    It is all down to personal preference in the end, the above are mine and are therefore correct:D
     
  11. Mark Ward

    Mark Ward
    Member

    Joined:
    Sep 12, 2001
    Messages:
    1,796
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    41
    Location:
    Kent
    Ratings:
    +18
    MattF Said
    Could you define your idea of a lot of power please?

    Would Denon AV-A10SE THX or POA-T10 THX be man enough?

    Cheers,
     
  12. Gary Lightfoot

    Gary Lightfoot
    Well-known Member

    Joined:
    Apr 6, 2001
    Messages:
    12,140
    Products Owned:
    0
    Products Wanted:
    1
    Trophy Points:
    136
    Location:
    Surrey. UK.
    Ratings:
    +1,953
    Hmmmm, looks like I'm going to have to try my bi-poles back in the side position with the direct radiators at the rear. Now that I've got a spl meter, I can set them up and see how they sound again.

    I'm wondering if it's just a personal preference thing in my case, or maybe my loft acoustics aren't giving the same results as a 'normal' shape room. what kind of sound levels are you using? Any idea? Maybe that makes a difference too - it seemed to when I tried them in the lounge that time.

    I'll let you know how I get on. :)

    Gary.
     
  13. Matt F

    Matt F
    Active Member

    Joined:
    Jul 18, 2000
    Messages:
    900
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    21
    Location:
    Chester, UK
    Ratings:
    +4
    Mark, I'd say the THX approved Denon setup you quote would certainly be man enough. I drive the KEFs with a Rotel RB985MKII 5 channel THX power amp (130 watts per channel) and this seems to work fine.

    Basically, you need to be looking at a genuine 100 watts per channel or so but also (and more importantly) an amp that won't turn itself inside out when presented with a 4 ohm load. There are plently of amps out there that can drive them but the cheaper AV amp/receiver would have a hard time - then again, I would have thought you're unlikely to want to put a pair of £700 surround speakers on the end of a £300 AV amp/receiver.
     
  14. DodgeTheViper

    DodgeTheViper
    Moderator

    Joined:
    Oct 23, 2001
    Messages:
    14,720
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    Inbetween Upgrades !
    Ratings:
    +3,501
    Hi Guy,s

    Just to throw something else into the equation as all your reply,s seem to be quite informative !

    What are your thoughts on tri-polar rear speakers used at the rear not side , as in M&K,s K4 tri-polar surrounds.

    All your comments appreciated

    Kev
     
  15. eman

    eman
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    The truth is with speakers is that they are not true bi/di-polar speakers, from what I have read in reviews on this site or elsewhere they are wired completely different to what it first seems.

    Personally, like many other comments made, it will all come down to personal preference, room size and the all important budget.
    ;-)

    So myself, I will probably go for dipoles at side, direct radiators up in rear corners high up and tilted downwards, and bipoles inbetween these, probably on wall too but slightly lower than directs.

    Just to highlight back to what Matt F and say to Gary Lightfoot "The difference sound-wise between the two is - the bi-poles spread the sound around the room quite well whereas the di-poles disappear altogether so that it's very difficult to pin-point where the sound is coming from - just what you want for movies."

    Its important to realise that your bi or di's don't overdo your fronts, where bipolars probably will, dipolars can work with or against!

    Finally, does anyone else know about the Jamo THX range of speakers?

    Keep up the volume, and watch T2 soon......

    E
     

Share This Page

Loading...