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Discussion Starter #1
ABEX,


In a previous thread we were discussing xover methodologies for the XR45.


You said,
Quote:
What I am saying is just take the signal from the Receiver and have the subs Amp crossovers point set to 60-80 and bypassing the receiver XO all together. It is still getting the signal,but you are deptermining the XO point through the outboard amp's XO pt..
If you feed a digital signal to the XR-45 and define sub=yes, you can't bypass the receiver's XO, i.e. there is no way to correctly implement what you are describing, unless you want to simply throw away all the bass from 100Hz down to 60-80Hz (this is actually the cascading XO problem I was describing).


Likewise, since the XR-45 amps are driving the speakers directly, there is no way to set sub=no and only use the sub's XO, feeding the output signal of the XR45 to the sub and then to the speakers won't work.


You also said,
Quote:
I always heard that was the best way to go with subs amp\\XO thereby defeating the XO of the receiver altogether.
Where did you hear that?


I'm not quite sure I know what kind of setup you are referring to here, so hopefully you can provide more detail about the setup.
 

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Quote:
Originally posted by dm
I have the XR45. I have the sub set to YES and XO is set to the default 100 hz (you cannot set it to disabled) and my main left right set to large.


For normal music, I get bass out my sub AND as far as I can tell also my mains.
The XR45 says that if you are using a sub to use the default front setting of "small", I see you are using the setting of "large" with your setup. Do you recommend that method? I've only had my XR45 for a couple days so I haven't toyed around with it much yet.
 

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My mains are good down to 40hz. So I used the setting large. I have XO and volume setting adjustments on my sub to compensate for the potential of too much base coming out of both. What bass I can get out of my mains is preferred since those speakers are better and smoother than my sub.


I do have to readjust a little for DD/DTS playback. Since my sub volume is a little low in that mode if I stick with my music calibration levels.
 

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Gotcha. My sub is my best speaker, a Klipsh KSW-12, and my fronts are fairly small (KSB - Alpha's) so I guess maybe our situations are quite different.
 

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Is there a way to adjust the fronts? On the remote, you can adjust the other speakers, but I have yet to find a way to adjust the fronts. (I'm not talking about setting from large to small, I'm talking the volume setting for the front).


Thanks
 

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Bruce D

I do not have a sub at the moment and was thinking of just running the line from the Outputs to a sub.How about the Second Audio Out from the receiver and using a powered sub with it's own internal XO to set the XO pt. below 100Hz..I am trying to think of how I had done it for someone in the past using an HK receiver. I know that person was having trouble with intergration and that is what we did to make the setup work better.


As far as where I heard\

ead it I would have to look through notes in order to specificly state who and where I read it from. I remember reading it and implementing it for someone using a receiver. It worked much better than using the receivers Sub Setting. Not making this up as I go along,but I do make mistakes like any normal person.L


I will look further into the equation.


Hope that helps!
 

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Quote:
Originally posted by rcmoto
Is there a way to adjust the fronts? On the remote, you can adjust the other speakers, but I have yet to find a way to adjust the fronts. (I'm not talking about setting from large to small, I'm talking the volume setting for the front).


Thanks
no level adjustment for the mains. You calibrate the rest of the speakers +/- in relationship to the mains. If you have a Left front vs Right front level problem, I guess you could use the balance setting in the tone controls.
 

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Thats what I thought on the speakers. I just wanted to make sure I was reading it right. Didnt mean to get off subject, it has a little to do with crossovers
 

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Discussion Starter #10
I was searching for a way to optimize the output to a sub without compromising the use of the Panny's digital amps, but I guess there just isn't one for DD/DTS 5.1 HT. I do it with my current system's regular analog amps and an external analog XO.


1) Unless mains have a -3dB to 20Hz, setting sub=YES and mains=Large is a serious negative compromise in bass quality. Normal config is sub=Yes and all speakers=small.


2) If the sub is connected to the XR45 sub-out, the XO on the sub should be set to off or to it's highest setting like 150Hz+. If not, then cascading XOs (combination of XR45 XO plus sub's XO) will produce very uneven bass frequency results.


3) Using the Second Audio out won't work for DD/DTS 5.1 either, it is only a stereo output.


Using the XR45 in stereo only, maybe you could actually use a digital xover (completely in the digital domain) between the PCM digital output and the XR45 digital input (something like a Beringer DCX2496 or a TACT), feeding the high-pass digital signal to the XR45 and sending the decoded analog low-pass to the sub.


It seems the only good way to use this unit is to use the XR45's internal 100Hz digital XO (all speakers=small) at the moment (sure wish they offered at least an 80Hz option).
 

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Only other way I see to do this easily is use the speaker-level ins on the sub - set SUB:NO, left/right Large, run your speaker cables to the sub (assuming it supports this - many do) set your X-over wherever you want on the sub, and run the left/right speaker cables from the sub to front speakers.


Not an ideal solution by any means, but it works.
 

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Les;

Yes,running the Mains through the subs inputs are not ideal. I cannot remember how I did it with an HK receiver so that it bypassed using the XO pt. of the receiver.


100hz. is to high for a good speaker system to use in conjunction with a sub. My main speakers roll=off at 40Hz. and to use a sub that is set at 100Hz. would suck!


Thx!
 

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Discussion Starter #14
Les and ABEX,


Doesn't running the XR45 main speaker outputs through a sub and then to the main speakers completely negate the sonic purity and damping control (tight bass) of the XR45 amplifiers over the main speakers?



My current setup works the way you both indicated above, with analog amps (prepro Sub=no, main speakers=Large, all other speakers=Small) and an external active XO (Marchand) between prepro, main speaker amps and powered sub (low-level RCA cables).


I'm mostly in agreement on 100Hz being too high, but I also think the typical 12dB high-pass XO slope is too gentle. Wish the XO was 80Hz with 24dB slope for both high-pass and low-pass.
 

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Discussion Starter #15
dm,
Quote:
why do you say this? I have not noticed a problem setting sub = yes mains = large. My mains only go down to 40hz.
You may not notice a problem, but you are likely missing bass frequency content from the main channels that your main speakers are simply not able to reproduce (typically just in 5.1 HT mode). It is also amazing to note the improvement in clarity of many main speakers when their amps are relieved of the lowest 1-2 octaves (20-80Hz) of bass frequencies that are handled by a more capable bass frequency radiator such as a sub.
 

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Quote:
Originally posted by BruceD
Les and ABEX,


Doesn't running the XR45 main speaker outputs through a sub and then to the main speakers completely negate the sonic purity and damping control (tight bass) of the XR45 amplifiers over the main speakers?
Like I said earlier and agree with Les that running the Mains through a sub is less than ideal and I never used main speakers in that hook-up option.


To follow-up on the original Q you had asked I think one of the major mags had stated that by-passing the XO or not using the LFE Out from a receiver is more beneficial if you have a good speaker array and good Sub. You should use the sub ,getting just the signal from the Receiver or Pre-Amp and use it's(sub) Amp and XO selector pt. to blend the speakers to the sub.


It makes more sense that way in order to defeat the 100hz. cutoff pt. that the receiver has.For my system even 80Hz. is to high and when I use to use NHT\\Velodyne and a JAMO Sub and use to set them between 30-40Hz. so that they blended better.The Vol. was set so that it did not attract attention as being noticed.Of course it did add sound to the presentation though.


You try to match the drop off bass freq pt. of your main speakers to the subs XO point.


As another suggestion.If you can tell there is a sub being used then you do not have it set correctly.Subs and Bass frequencies should not be noticed as a source.If you can notice that sound is coming from the box when listening to something then it is set to high.

That is a hard one to describe,but to put another way subs should be noticed as far as adding dimentionality to the sound,but not draw attention to themselves.


Sorry I cannot be more descriptive as to get accross,but I hope you get the meaning as to what I am trying to describe.


Later!
 

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Discussion Starter #17
Quote:
You try to match the drop off bass freq pt. of your main speakers to the subs XO point.
My point is, this is almost impossible to do correctly and get a clean transition across the XO boundary with only the low-pass filter on a sub (not to mention the rather cheap XOs found in many subs) .

Quote:
You should use the sub ,getting just the signal from the Receiver or Pre-Amp and use it's(sub) Amp and XO selector pt. to blend the speakers to the sub.
Can't say I agree with that point of view, too many unknown variables (the sub's XO) that you can't control.


One of the best ways to implement a main speaker-to-sub XO is to use an active external symmetrical (24dB slope Linkwitz-Riley high-pass and low-pass) XO with the XO frequency between 1/2 to one full octave above the main speakers f3. This way the SPL levels will sum to flat across the crossover boundary (something you won't be able to do with your method).


I do this with mains whose f3 is 32Hz and I use a 60Hz crossover. By the way this works for both 2-channel stereo and DD/DTS 5.1, and I don't have to adjust the sub levels when going from one to the other.
 
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