New Cirrus Triple-Xover a good thing?

Discussion in 'Archived Threads 2001-2004' started by BruceD, Mar 5, 2002.

  1. BruceD

    BruceD Screenwriter

    Joined:
    Apr 12, 1999
    Messages:
    1,220
    Likes Received:
    0
    Do you think the new Cirrus DSP's Triple Xover option provides a better integration of multiple speakers than one xover frequency for all speakers?

    I think having the option to implement the best xover for a particular speaker, taking into account it's rolloff characteristics, is better than the same All-in-One xover for all speakers. My experience with custom electronic crossovers for my mains and sub leads me to believe this may be true.

    I think it depends on the speakers, but for those of us without identical speakers for every channel, I think it may provide a better solution.

    As an example:

    Mains xover @60Hz

    Center xover @100Hz

    Surrounds xover @80Hz
     
  2. Lewis Besze

    Lewis Besze Producer

    Joined:
    Jul 28, 1999
    Messages:
    3,134
    Likes Received:
    0
    This may not be as simple,since you wan't the sub to integrate as well.Naturally the sub's crossover should be set to the highest setting of the others,like in your case 100hz!

    However when I get the Outlaw I will experiment!
     
  3. Ron Alcasid

    Ron Alcasid Stunt Coordinator

    Joined:
    Apr 11, 2000
    Messages:
    168
    Likes Received:
    0
    On the other hand, if you don't have identical speakers wouldn't you want to minimize any differences between them? Why throw different x-overs into the mix? I'm not saying one way is better than the other, just presenting a different point of view.
     
  4. BruceD

    BruceD Screenwriter

    Joined:
    Apr 12, 1999
    Messages:
    1,220
    Likes Received:
    0
    Ron,

    So, does that mean you think different xovers maximizes the differences between speakers?

    Not sure I buy that, but I'm thinking about it.
     
  5. Ron Alcasid

    Ron Alcasid Stunt Coordinator

    Joined:
    Apr 11, 2000
    Messages:
    168
    Likes Received:
    0
     
  6. BruceD

    BruceD Screenwriter

    Joined:
    Apr 12, 1999
    Messages:
    1,220
    Likes Received:
    0
    OK.

    So what is the ideal setup?

    5 identical full range speakers? I'm not sure this is true, because the bass will be negatively affected.

    5 identical speakers all with the same 80Hz xover? This is the question, and I'm not sure that is true either. i.e the reason for this thread.
     
  7. Sankar

    Sankar Second Unit

    Joined:
    Aug 1, 1999
    Messages:
    315
    Likes Received:
    0
    I personally think that having crossovers tuned to each specific speaker cannot hurt. I think that it all depends on whether the crossovers are applied before or after the time delay adjustments.
    I'm pasting a response that I had posted on another discussion (The NEW Anthem AVM-20 Thread) .. its probably more appropriate here.
    ------------------------------------
     
  8. Robert Elliott

    Robert Elliott Stunt Coordinator

    Joined:
    Feb 18, 2002
    Messages:
    103
    Likes Received:
    0
    I believe the flexibility to 'tune' your receiver/pre/pro to your specific speakers is the best bet. Yes, it adds complexity to the system setup but is then done.
     
  9. Evan S

    Evan S Cinematographer

    Joined:
    Nov 21, 2001
    Messages:
    2,210
    Likes Received:
    0
    There is a good discussion of this over at AVSForum where Brian Florian trys to explain his remarks regarding the lack of the triple crossover in the Anthem and how this might be a good thing. It's in the "Question for Brian Florian" thread, I think started by the same BruceD that started this thread.
     
  10. Rusty J.

    Rusty J. Agent

    Joined:
    Mar 3, 2002
    Messages:
    27
    Likes Received:
    0
    It seems to me, after reading Brian Florian's comments that using different crossovers will only have a negative impact if you send a identical signals to at least two of your speakers that have different crossovers. On the basis of maximizing each speakers sonic potential, I think having the choice to set different crossovers for front, center and rear speakers is a good one to have.
    Of course, I'm a rookie so what do I know. [​IMG]
     
  11. BruceD

    BruceD Screenwriter

    Joined:
    Apr 12, 1999
    Messages:
    1,220
    Likes Received:
    0
    I'm not sure there is any clear picture on this yet.

    A comment by Phillip Brandes in the same AVS thread regarding Brian's statements from a written product review:

     
  12. Brandon B

    Brandon B Second Unit

    Joined:
    Mar 23, 2001
    Messages:
    263
    Likes Received:
    0
    Regarding Sankar's point about large vs. small, Brian and others have all actually said that you will get better performance setting all your speakers to small, and have stated why, so in that sense, we have heard that it is a problem before.

    Given that, however, I disagree that the triple XO WILL do more harm than good, but would instead think it CAN do more harm than good if not used correctly.

    My 3 mains are (well, will be as soon as I finish making them) 3 identical 2 ways actively crossed and bi-amped with three sealed box woofers. My 4 surrounds are more of the same 2 ways with no woofer. This 2 way on its own is flat to low 60Hzish range. WIth the woofer, it is flat to about 32Hz, and strong down to mid 20's. For me to XO all these at the same point, it would need to be 120 Hz following Brian's and other's advice that the XO be 1 octave above the flat response of the speaker.

    My plan is rather to cross my mains at 60Hz. My center will possibly be higher, as it sits on the same stand as my TV, and I may need to redirect some of the bass (esp. the LF) to my sub.

    Brian's advice generally assumes that unloading the mains from the lower 2-4 octaves will improve their performance as the sub is more able to handle it. In my system, this is not really true, as my 3 main woofers are (combined) capable of 30-40% of the output of my sub, and they are only covering the bottom 4 octaves, so having them only cover 1 of these octaves (120-250) will tax my sub to no real benefit (they would have to all XO at 120 because of the surrounds). Additionally, as they are low Q sealed units vs. a PR sub, the sound quality would arguably suffer slightly.

    My setup is not really the norm, however, as even most people with large mains do not necessarily have them bi-amped. It is by no means unique, though, and think the triple XO isvery suited to this type setup. It is, inn fact, the primary reason I originally planned on the 950.

    BB
     
  13. Will

    Will Guest

     
  14. BruceD

    BruceD Screenwriter

    Joined:
    Apr 12, 1999
    Messages:
    1,220
    Likes Received:
    0
    Will,

    I'm confused. Why would you cross mains at 40Hz? I understand a center at 100Hz.

    Mains crossed @40Hz traditionally means they still produce strong output a full octave lower than that (20Hz).

    Now a pair of mains with strong 20Hz content is likely going to produce some comb filtering (nulls and peaks) with each other in the lowest octave of bass frequencies.
     
  15. Michael Mohrmann

    Michael Mohrmann Screenwriter

    Joined:
    Dec 30, 2001
    Messages:
    1,394
    Likes Received:
    0
    Will,

    If the processor or receiver in question is performing the bass management internally, then the subwoofer should be set to bypass mode or to the sub's highest available crossover setting. Avoid cascading crossovers with the sub.

    In addition, you risk cutting off the LFE channel (if available) which can go as high as 120Hz. Of course, if your subwoofer can't go that high, then you may have no choice but to set a crossover (okay, exception to the rule!).

    Michael
     
  16. Brandon B

    Brandon B Second Unit

    Joined:
    Mar 23, 2001
    Messages:
    263
    Likes Received:
    0
    If you are using the bass mgmt of the 950, your sub doesn't have "a" crossover, it has 3 (excluding any XO built into your sub, which should be bypassed or turned up until it is effectively inactive).

    The only way material from your center would go to your mains is if your mains are set to large, your center to small, and sub set to "no", or a "redirect LFE to mainns" type setting, which I don't know if the 950 has.

    The bass mgmt circuit takes the 6 channles of info (5 +LFE). With no (all speakers at "large", sub to "yes") bass mgmt, it sends them directly to your speakers and sub unaltered and not diverted.

    With any speakers set to small and sub to "yes", info below XO point for the speakers set to small (i.e. 100 Hz for your center) will go to the sub only.

    BB
     
  17. Will

    Will Guest

    BruceB,
    Even though I am among the fortunate few to have speakers rated down to 20 Hz (Von Schweikert VR 4 Gen II's) they are rated at -3 db at the extremes and it is my understanding that it is better to crossover an octave higher than the -3 db point to achieve near flat frequency response.
    That's one reason the subwoofer is there -- it is flat supposedly to below 20 Hz.
    Truth be told, for music, I probably will disengage the crossovers on the mains since there's not too much content under 20 Hz except for organ and canon (War of 1812, etc.) and there's not that much content the next octave up, under 40 Hz, except for synth and rap-type music which I don't listen to much.
    But for most movies, the high volume of frequencies under 60 Hz in the crashes, thuds and thundering shudders, will probably necessitate a higher crossover point than 40 Hz.
     
  18. MatthewJ S

    MatthewJ S Supporting Actor

    Joined:
    Feb 27, 2001
    Messages:
    584
    Likes Received:
    0
    Let me add another wrinkle....how many speakers crossed at 80hz play flat to 40?..I do not subscribe to the theory of "one full octave below crossover", because while using ref30 & avr307's crossover and notch filtering and playing w/BFD'S, I seem to find real world room results have me setting the crossover points lower...I do understand the theory and on it's face it makes sense...Do I?
     
  19. Will

    Will Guest

    As long as you aren't pushing the speakers by playing too loud, I think you can, by equalization, get more speaker range. Whether it's best to equalize the speaker or to redirect low frequencies to a subwoofer is I suppose a choice. I think I'd rather send what my speaker can't do well to the sub via a crossover, but certainly can understand others who want to equalize the sound electronically instead.

    However, music played loud outside the speakers operating frequencies can cause noticable sound distortions when the speakers aren't designed for sound outside of its range, and may even damage your speaker especially if it doesn't have an internal crossover to remove damaging, out of range, frequencies.
     
  20. Ron Alcasid

    Ron Alcasid Stunt Coordinator

    Joined:
    Apr 11, 2000
    Messages:
    168
    Likes Received:
    0
    BruceD,

    I think the ideal setup would have 5 identical speakers and a sub, all with the same xover. The xover point would depend on the capabilities of the speakers and the sub, so it would be desirable to adjust the xover point. The goal of surround sound is to create a seemless 360 degree soundfield, so in the ideal setup every speaker would sound exactly alike. Of course we don't live in an ideal world. My front speakers are bigger than my surrounds, my center channel speaker lies horizontal and has two midrange drivers and a tweeter between them. Every little difference puts you further away from having that seamless 360 degree soundfield. Having different xovers for the mains, center and surrounds doesn' t help.

    I think the reason some of us want different xovers for the mains is to maximize them fo 2 channel playback. That's understandable since we have huge towers speakers and a mega watt amp to drive them but I don't think triple xovers are the answer. IMHO the ability to set different xovers for 2 and 5 channel playback would be more useful.
     

Share This Page