Does the subwoofer's crossover matter when listening to 5.1 sound?

Discussion in 'Archived Threads 2001-2004' started by Bob McLaughlin, Apr 3, 2002.

  1. Bob McLaughlin

    Bob McLaughlin Screenwriter

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    Okay, I know the other 5 speakers' individual crossovers matter, but when you're listening to 5.1 sound, the subwoofer is going to be fed the dedicated LFE channel regardless of the sub's crossover setting; is this correct?
     
  2. John Kotches

    John Kotches Cinematographer

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    Bob,

    Some subs have a specific LFE input, which will bypass the subwoofers internal crossover.

    Others don't.

    Regardless, if you dial the subwoofers crossover to the highest value, you effectively move it out of the way so that the subs crossover doesn't interfere with the receiver/processors crossover.

    Regards,
     
  3. Keith Mickunas

    Keith Mickunas Cinematographer

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    Bob, how is your sub connected? My understanding is that if you connect to the sub/lfe out on your receiver or pre/pro, then you should set the crossover on the sub to the maximum position unless the sub ignores the crossover on the input, in which case it wouldn't matter.

    edit: John posted when I wrote mine, listen to him, he explains it better.
     
  4. Bob McLaughlin

    Bob McLaughlin Screenwriter

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    I just got an SVS 20-39 PCi yesterday, and it has a switch to disable the sub's crossover, which I did as the manual recommended. This means my receiver is doing all the bass management. I have a dedicated sub output on the receiver, and have connected it to the sub via the low-level input. I was just asking the question to see if I understood this correctly as far as 5.1 sound was concerned.

    Now, on the other hand, I still have to tweak the individual crossovers on my receiver for each of the other five channels. The factory default is 120 Hz but I'm going to have to play around with these until I get what sounds best. If I set the front main speakers to, say 90 hz, anything they get below this range will be routed to the subwoofer, correct? Will these crossovers apply to stereo sound as well?
     
  5. Keith Mickunas

    Keith Mickunas Cinematographer

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    Bob, crossovers in receivers work differently based on model. Post what you got and hopefully some others with the same receiver can tell you what it does. I think you've got the right idea though, fiddle with it until it sounds best to you.
     
  6. Bob McLaughlin

    Bob McLaughlin Screenwriter

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    It's a Sony STRD series, I'm not sure exactly what the model number is (I'm at work and I'm supposed to be working now!)
    I did a search and found this guy's thread,
    http://www.hometheaterforum.com/htfo...+svs+crossover
    he seems to be in the same boat as me, although his questions are a little different. Like you said, I'll just keep making adjustments until I get it where I want it to be. Thanks!
     
  7. Dan Joy

    Dan Joy Supporting Actor

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    Bob, I am that guy. My PPCi is due today(gotta rush just to go to the bathroom so I don't miss BROWN). I was anxious to hear what you and others are doing with front vs large. I listened to HFO with front to small without sub and mids and highs sounded awfull. I have calibrated both ways (front vs small) and havent noticed differance with mains center or surround settings. Let me know what ya do!
     
  8. Vin

    Vin Supporting Actor

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  9. Bob McLaughlin

    Bob McLaughlin Screenwriter

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    Thanks, Vin! That's what I wanted to know.

    Dan, I have all of my speakers set on "small" at this point. I have read many threads on this and that seems the way to go. I just feel I need to bring down those speaker's crossovers a bit, because the subwoofer is a little overwhelming. But when I run test tones it is only 3-5 dB higher than the other speakers, which is what SVS recommends for moderate listening levels. I think it will match up better with my other speakers once I let them share a little more of the bass load.
     
  10. Dan Joy

    Dan Joy Supporting Actor

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    How will you change the other speakers xover? What model receiver do you have?
     
  11. John Kotches

    John Kotches Cinematographer

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    Guys,

    While the spirit of the statement: Everything below crossover frequency gets routed to the sub is correct, the practice is a bit different.

    Consider a target SPL of 75dB, with a THX crossover (24dB/octave low pass, 12dB/octave high pass) engaged at 80Hz:

    Frequency....Main dB....Sub dB

    320Hz..........74+........24

    160Hz..........74.........48

    80Hz...........72.........72

    40Hz...........60.........74+

    20Hz...........48.........74+

    Given our brains perceptual functioning, we perceive one as taken over, but it isn't quite that way.

    Sorry to be picking nits here guys, but it's worth at least examining.

    Regards,
     
  12. Bob McLaughlin

    Bob McLaughlin Screenwriter

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    Of course you're exactly right, John. I remember seeing a chart that illustrated your point graphically, but I'll be damned if I can find it now.

    Dan, I believe mine is a STRDE-835 like yours, but I will have to verify this when I get home. It might be different. Anyway, on mine at least, there is a tiny button down by the jog dial, I think down in the 7 o'clock position. I think it's called "setup". You hit that, then hit the arrow buttons up above until crossover words (which speaker and how many Hz) come up in the display. Then, you can use the jog dial to adjust your crossovers for specific channels, I believe in 30 Hz increments.
     
  13. Bob McLaughlin

    Bob McLaughlin Screenwriter

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    Sorry Dan, I checked and mine's an 845, not an 835. So your options might differ from mine.
     
  14. Dave Schofield

    Dave Schofield Second Unit

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    If one were to used the LFE-out instead of (what I would call) main channel bypass, does the subwoofer still get fed during CD or 2-channel playback? Restated, is the LFE-out regulated by the receiver or by the Dolby/DTS codec (which would, conceivably, not be in use during 2-channel playback)?
     
  15. Cave Canem

    Cave Canem Auditioning

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    If I turn my Crossover all the way up the bass is just to much to handle, stuff falls of the walls and entertainment center, wife gets mad. Its not a pretty picture.

    I usually keep mine around 80hz and let my towers handle the rest. That way I get the nice deep base from the woofer and the ambient base from the towers.

    I have the STRDE-445. Older model but works great.
     
  16. Vin

    Vin Supporting Actor

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  17. John Kotches

    John Kotches Cinematographer

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    Cave,

    Then you are losing information between 80 and 120Hz on the LFE channel.

    It's fine as your choice, but I wonder if your results might be a result of miscalibration.

    Are you running the sub hot be a few dB by chance?

    Regards,
     
  18. Cave Canem

    Cave Canem Auditioning

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    hmm, Interesting.
    You have brought up some very good points. Im not real up to date on the proper setup of a HT system. I have just recently purchased all the required speakers so that I can have full SS. I have my Sub plugged into the 'sub-out' RCA jack on the reciever and into the 'line-in' jack on the Sub. I have the polarity set to normal or 0. SW is 'on' in setup and the volume is around 2 in setup.
    My problem is that my wife hates the sub, the only way she will tolerate it is I have it toned down to where you can barely hear it. I set it to 80 b/c most explosions will be lower base and thats when you will hear the sub, or so my thinking goes. [​IMG] When I have it set to 120Hz there is just entirely to much base, even messing with the volume knob doesn't help to much. Its a 12" 120W front fireing woofer. I have messed around with it and have gotten it to where it sounds pretty good and the wife isn't mad. I have never calibrated my stereo other then by ear and it seems to sound nice as is, granted im sure its way off compared to some standards but I have to make the wife happy.
    I keep my towers set to large so they will cover the largest Freq Range as possible, I have my Sub set to around 80hz to cover the lower 'rumbling' bass. You guys have made some good points so I will play some more when I get home. I also listen to a lot of music and Hz set any higher then 80 is to much base and overpowering for my apartment.
    Thanks for the advice and tips. Keep em coming if you have any more.
    Edit: My woofer will adjust from 50hz to 170hz.
     

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