Dolby Lab's recommendation on full range speakers at all channels...

Discussion in 'Archived Threads 2001-2004' started by John H, Jan 14, 2002.

  1. John H

    John H Second Unit

    Joined:
    Nov 27, 1998
    Messages:
    472
    Likes Received:
    0
    Trophy Points:
    0
    I sent a question to Dolby Labs and this is the answer I received.
    Question:
    Does Dolby Labs recommend "full range" speakers at all channels and a subwoofer in a 5.1 system over a Sat/Sub combination?
    Answer:
    "The ultimate, ideal, cost-no-object system (i.e tens of thousands of dollars) might very well incorporate identical full-range speakers at the five main channels. More important, though, is that they all have similar, preferably identical, timbre or tonal balance. For example, if you use five identical, high quality satellites and a sub that crosses over no higher than about 80 Hz, there would be very little if any disadvantage over five similarly balanced full range speakers plus a sub. Perhaps a tad more power handling at the low end with the full-rangers, but little else. For most people, cost is an object, so a well designed satellite system, particularly one with a relatively low crossover and a well-designed heavy-duty sub, is the answer, even for perfectionists."
    Best regards,
    Dolby Customer Support
     
  2. Chuck C

    Chuck C Cinematographer

    Joined:
    Jan 6, 2001
    Messages:
    2,224
    Likes Received:
    1
    Trophy Points:
    0
    sounds reasonable to me.
     
  3. Bob_A

    Bob_A Supporting Actor

    Joined:
    Jul 30, 2000
    Messages:
    876
    Likes Received:
    0
    Trophy Points:
    0
    For HT, I see no reason why 5 identical satellites + quality external sub(s) would not be a high performance and highly cost effective approach...though I still feel that there can be some benefits when having near full range speakers. Notice that Dolby mentions a subwoofer which must be crossed below 80Hz...but are they saying that the lower the crossover, the better? Notice the tact on their part...the crossover point below 80Hz excludes the perfectly timbre matched BOSE AM sub/sat systems! [​IMG]
     
  4. Chuck C

    Chuck C Cinematographer

    Joined:
    Jan 6, 2001
    Messages:
    2,224
    Likes Received:
    1
    Trophy Points:
    0
    I imagine that full range speakers are suited more for music. In the HT, that may not me the case...just look at M&K 150 speakers. They're not full range at all.
     
  5. Bob_A

    Bob_A Supporting Actor

    Joined:
    Jul 30, 2000
    Messages:
    876
    Likes Received:
    0
    Trophy Points:
    0
    Good point Chuck...some near full range speakers probably cater towards the 2-channel crowd [​IMG]
     
  6. Bob_A

    Bob_A Supporting Actor

    Joined:
    Jul 30, 2000
    Messages:
    876
    Likes Received:
    0
    Trophy Points:
    0
    From Dolby's website:

    Satellite/subwoofer systems take advantage of the fact that the lowest bass frequencies are non-directional, which means the ear cannot readily detect where bass sounds are coming from. As a result, these systems channel the low bass to a dedicated bass speaker called a subwoofer. The subwoofer can usually be tucked out of the way, because its placement is not critical to reproducing the directionality of the original sound.

    Because they are not required to reproduce low bass, the satellite speakers can be compact, making them less intrusive and easier to place. Many systems use identical satellites for the left, center, right, and surround channels. This means that all speakers have the same timbre, or tonal characteristic, which is desirable in a home theater system. Other systems provide identical satellites for left, center, and right, but the surround units may be somewhat different, usually with respect to their radiating characteristic. Nevertheless, the surround speakers should still be timbre-matched to the front speakers.

    Of course, there are excellent alternatives to satellite systems. For example, you can create a home theater system using larger, full-range tower speakers for the front left and right channels, or for both the front and the surround channels. Their manufacturers usually provide well-matched center and surround speaker options. Some of today's tower speakers have built-in powered subwoofers, making them particularly suitable for a home theater.

    __________________________________________________ ________

    Dolby seems pretty flexible on their recommendations...Ultimately, it seems like a preference thing.
     
  7. Adil M

    Adil M Supporting Actor

    Joined:
    Nov 21, 2001
    Messages:
    922
    Likes Received:
    0
    Trophy Points:
    0
    Right, when I was reading it I was smiling and knew who was going to jump in the conversation. See, Full-range is better ideally, but in a real world the sub/sat is much more efficient. However, I won't comment too much on this b/c I don't have a sub and since I haven't lived w/ one, I might be biased in my rec'ds despite working w/ audio on a daily basis. [​IMG]
     
  8. Bob_A

    Bob_A Supporting Actor

    Joined:
    Jul 30, 2000
    Messages:
    876
    Likes Received:
    0
    Trophy Points:
    0
    Adil, I never said that near full range speakers all around was practical (particularly for relatively small rooms)! But it sure is nice for the main channels, and I have seen several people on these forums who enjoy it for the rear channels [​IMG] I think it has something to do with the overall soundstage and presence from such a setup involving near full range mains all around vs. smaller satellites all around.
     
  9. BruceD

    BruceD Screenwriter

    Joined:
    Apr 12, 1999
    Messages:
    1,220
    Likes Received:
    0
    Trophy Points:
    0
    It's not the type of speaker that matters, what matters is where the -3dB point for low frequency output is and what type of crossover slopes are involved.

    I find the best way to get a smooth integration of mains and subs for optimum performance is to have mains whose -3dB low frequency is at least a full octave below the crossover frequency. This means for an 80Hz crossover you want mains (sats or towers) that have a -3dB of 40Hz.

    I get really good sub integration with a 60Hz crossover rather than the traditional 80Hz, and my mains go down to 32Hz. I get a very smooth transition, so good I use my mains+sub with 2-channel music.
     
  10. Lewis Besze

    Lewis Besze Producer

    Joined:
    Jul 28, 1999
    Messages:
    3,134
    Likes Received:
    0
    Trophy Points:
    0
    Bruce,[​IMG]
    If one plan on to get fullrange speakers all around,then one better aquinte onself with the room's acoustic properties before doing so.Especially if there is another sub in the "picture" as well.
    To get them work properly is a lot of work,without instrumentation,and lack of knowledge,and experience.
    Otherwise you either get lucky,or having a "mess" in your hand.
     
  11. BruceD

    BruceD Screenwriter

    Joined:
    Apr 12, 1999
    Messages:
    1,220
    Likes Received:
    0
    Trophy Points:
    0
    You are absolutely correct Lewis.

    I spent a fair amount of time with my ETF5 Acoustic Measurement Software and a calibrated mic/mic-preamp when positioning speakers, sub and listening positions in my room.
     
  12. Lee-c

    Lee-c Second Unit

    Joined:
    Sep 2, 2000
    Messages:
    497
    Likes Received:
    0
    Trophy Points:
    110
    Tom over at SVS says that a 100Hz crossover works just as well as a 80Hz, as far

    as localization concerns go. How well the sub blends with the mains would depend heavily

    on exactly what speakers your matching together, obviously.
     
  13. Adil M

    Adil M Supporting Actor

    Joined:
    Nov 21, 2001
    Messages:
    922
    Likes Received:
    0
    Trophy Points:
    0
    I was reading this thread once.. and these guys were arguing about something like towers vs. sat/sub combo and one guy didn't have a sub in his setup and the other guy used multiple subs in different areas of his listening room b/c he liked the effect better. It was ironic. But one guy was one guy and the other guy was the other guy.
     

Share This Page