Efficiency: 90db

simphiwes
simphiwes Posts: 116
edited May 2006 in Speakers
On the Rti8 specifications it says Efficiency: 90db, what does this mean?
(((((STEREO)))))
System 1(complete)
Front: Rti8
Intergrated: Valve Audio Epsilon
CD Player: Xindak Muse Delux 1.0
Media Player: Mede8er MED 200
Behringer DAC
Post edited by simphiwes on
· Share on FacebookShare on Twitter

Comments

  • VR3
    VR3 Posts: 28,781
    edited May 2006
    With 1 Watt at 1 Meter - they play 90db.

    That means at 2 Watt/1 Meter they play 93db.

    4 Watt/1 Meter, 96 DB
    8 Watt/1 Meter, 99 DB
    16 Watt/1 Meter, 102DB
    32 Watt/1 Meter, 105DB

    So on and so on.
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
    · Share on FacebookShare on Twitter
  • McLoki
    McLoki Posts: 5,231
    edited May 2006
    Another thing to keep in mind is that the sound level drops by 6db every time you double the distance.

    90db at 1 meter = 84db at 2 meters (about 6.5 feet) = 78db at 4 meters (about 13 feet)

    Starting from there (depending on your listening distance from the speakers) add the power requirements like Sid did above.

    Michael
    Mains.............Polk LSi15 (Cherry)
    Center............Polk LSiC (Crossover upgraded)
    Surrounds.......Polk LSi7 (Gloss Black - wood sides removed and crossovers upgraded)
    Subwoofers.....SVS 25-31 CS+ and PC+ (both 20hz tune)
    Pre\Pro...........NAD T163 (Modded with LM4562 opamps)
    Amplifier.........Cinepro 3k6 (6-channel, 500wpc@4ohms)
    · Share on FacebookShare on Twitter
  • simphiwes
    simphiwes Posts: 116
    edited May 2006
    How Loud is 90db compratively speaking?
    (((((STEREO)))))
    System 1(complete)
    Front: Rti8
    Intergrated: Valve Audio Epsilon
    CD Player: Xindak Muse Delux 1.0
    Media Player: Mede8er MED 200
    Behringer DAC
    · Share on FacebookShare on Twitter
  • SDA SRS 1.2
    SDA SRS 1.2 Posts: 255
    edited May 2006
    simphiwes wrote:
    How Loud is 90db compratively speaking?

    Here's a table from an old physics text that might be helpful:

    Near total silence - 0 dB
    A whisper - 15 dB
    Normal conversation - 60 dB
    A lawnmower - 90 dB
    A car horn - 110 dB
    A rock concert or a jet engine - 120 dB
    A gunshot or firecracker - 140 dB
    Main System: Polk SDA SRS 1.2 Speakers, Sunfire Signature 600~two Amp, Carver C-16 Preamp, Carver TX-11b Tuner, Marantz 6350Q TT, Philips CDR-775 Recorder, Teac V-707RX Cassette Deck, Signal Cable Double Run Speaker Cable

    Upstairs Den: Marantz 2325 Receiver, Marantz 5220 Cassette Deck, Marantz HD-880 Speakers, Marantz 6370Q TT

    Exercise (Kabuki speaker) Room: Kenwood KR-9600 Receiver, Pioneer CS-99a Speakers, Sansui SP-X9000 Speakers (not pretty, but LOUD! :) )
    · Share on FacebookShare on Twitter
  • Refefer
    Refefer Posts: 1,280
    edited May 2006
    Another thing to note is that that rating is given in an anechoic chamber. In room sensitivity almost always improves by a couple decibels for so.
    Lovin that music year after year.

    Main 2 Channel System

    Polk SDA-1B,
    Promitheus Audio TVC SE,
    Rotel RB-980BX,
    OPPO DV-970HD,
    Lite Audio DAC AH,
    IXOS XHA305 Interconnects

    Computer Rig

    Polk SDA CRS+,
    Creek Audio 5350 SE,
    Morrow Audio MA1 Interconnect,
    HRT Music Streamer II
    · Share on FacebookShare on Twitter
  • michael_w
    michael_w Posts: 2,813
    edited May 2006
    90dB is quite loud. When I have things pretty cranked it's usually around 95 to 100dB... that being said you have to be careful because permanent hearing loss begins at about 85dB.

    If you can, maybe try to pick up an SPL meter. It measures the sound pressure level (in decibels) and can help you do things like calibrate your system for home theater or trying to integrate a sub.
    · Share on FacebookShare on Twitter
  • MLZ
    MLZ Posts: 214
    edited May 2006
    To a NewB, it would seem that efficiency should directly correlate with power required to drive the speakers. But I look at some Polk speaker specifications for recommended power for speakers with an efficiency of 90 dB and see:
    RTi12: 50 – 500 watts per channel
    RTi8: 20 - 250 watts per channel
    Monitor 50: 20 – 275 watts per channel
    R50: 20 – 150 watts per channel

    Where am I going wrong? Is there any relation to efficiency and power required?
    · Share on FacebookShare on Twitter
  • McLoki
    McLoki Posts: 5,231
    edited May 2006
    MLZ wrote:
    Where am I going wrong? Is there any relation to efficiency and power required?
    Think of it as Power the speaker can handle rather than power required. As you move up the speaker lines, the power that the speaker can handle is related to the quality of the drivers and the way the drivers are wired withing the speaker (typically more speakers allows for more power handling...)

    Power handling and efficiency is really not as closely related as you would think.

    Michael
    Mains.............Polk LSi15 (Cherry)
    Center............Polk LSiC (Crossover upgraded)
    Surrounds.......Polk LSi7 (Gloss Black - wood sides removed and crossovers upgraded)
    Subwoofers.....SVS 25-31 CS+ and PC+ (both 20hz tune)
    Pre\Pro...........NAD T163 (Modded with LM4562 opamps)
    Amplifier.........Cinepro 3k6 (6-channel, 500wpc@4ohms)
    · Share on FacebookShare on Twitter
  • simphiwes
    simphiwes Posts: 116
    edited May 2006
    "For the most people, the easiest and best sounding thing to do is connect the subwoofer to the Front Left and Right speaker outputs. You can either connect your front main speakers to the subwoofer's speaker output terminals or you can "parallel wire" them to the same terminals. "

    Can someone explain this to me. i found this on the Bass Management article, unless i am really dumb but i do understand this method?
    (((((STEREO)))))
    System 1(complete)
    Front: Rti8
    Intergrated: Valve Audio Epsilon
    CD Player: Xindak Muse Delux 1.0
    Media Player: Mede8er MED 200
    Behringer DAC
    · Share on FacebookShare on Twitter
  • simphiwes
    simphiwes Posts: 116
    edited May 2006
    sorry to deviate here but i just had to ask the previous question.
    (((((STEREO)))))
    System 1(complete)
    Front: Rti8
    Intergrated: Valve Audio Epsilon
    CD Player: Xindak Muse Delux 1.0
    Media Player: Mede8er MED 200
    Behringer DAC
    · Share on FacebookShare on Twitter
  • simphiwes
    simphiwes Posts: 116
    edited May 2006
    Can someone explain this to me. i found this on the Bass Management article, unless i am really dumb but i dont understand this method?
    (((((STEREO)))))
    System 1(complete)
    Front: Rti8
    Intergrated: Valve Audio Epsilon
    CD Player: Xindak Muse Delux 1.0
    Media Player: Mede8er MED 200
    Behringer DAC
    · Share on FacebookShare on Twitter
  • MLZ
    MLZ Posts: 214
    edited May 2006
    McLoki wrote:
    Think of it as Power the speaker can handle rather than power required. As you move up the speaker lines, the power that the speaker can handle is related to the quality of the drivers and the way the drivers are wired withing the speaker (typically more speakers allows for more power handling...)

    Power handling and efficiency is really not as closely related as you would think.

    Michael

    So the upper number is max power that a speaker can handle.

    But shouldn't the lower number be the minimum amount of power a speaker requires and so be the same for all speakers rated at 90dB?
    · Share on FacebookShare on Twitter
  • holtzd
    holtzd Posts: 3
    edited May 2006
    simphiwes wrote:
    "For the most people, the easiest and best sounding thing to do is connect the subwoofer to the Front Left and Right speaker outputs. You can either connect your front main speakers to the subwoofer's speaker output terminals or you can "parallel wire" them to the same terminals. "

    Can someone explain this to me. i found this on the Bass Management article, unless i am really dumb but i do understand this method?

    As the article says, the bass management in the receiver doesn’t always do the best job of directing the bass where it needs to go. I have large main speakers so I want the sub to take over where the mains start to roll off. I have taken the advice this article suggests and it is easier to blend the subwoofer with the main speakers because you can use the adjustments on the powered subwoofer. The options you have for bass management in your receiver may be limited. Not all receivers and speakers are created equal though so you have to experiment and use what is best for your combination.
    · Share on FacebookShare on Twitter