Amp matching in Bi-amping - ideas check

[substance]

Originally Posted by GaryProtein

What are you presently using the XVR1 for if not in this set-up?

I like my XVR1, but if you want room correction, the extra poles and use of shelving in a crossover still will not perform room correction. Furthermore, who is to say your room needs correction around the crossover points?

I doubt you will use the third and fourth poles for 18 and 24dB/octave. You'll most likely use the first and second poles for 6 or 12 dB slopes. The speakers may not even sound good with 18 or 24dB/octave slopes.

3rd and 4th order would probably cause phase issues and extra stress on the amps. I am pretty sure the original passive xover on the CLX is a 1st order high pass filter at 360Hz for the mid-high panel and 2nd order low pass somewhere in 330-350Hz for bass panel. I don't see any band limiting filtering on the bottom. 56Hz at -3db is bass panel's own characteristics.

For correcting the response, you don't need to use all the poles on xover points. You can try placing one or two poles on the very bottom (22hz or 36Hz) should significantly flatten the response of the bass panel up to mid regions, another pole or two on the other side (330Hz or 360Hz). In 3 way, you have 12 poles with the xvr1. If you set it up properly, you can remove nulls and significant peaks. You will be left with 1-2db fluctuations in the longer bands but anything under 3db is indistinguishable to human hearing. It's a lot of work, like tens of hours of calibrating perhaps (digital room eq does this in minutes) but that's ok with me. At the end, you are rewarded with never to digitize your signal.

On a second thought, writing a matlab code for playing with the poles would help figure out where to use poles. Matlab code would assume petfect flat response of course but it would help you calculate the curve if you have to place to poles very closely.

[GaryProtein]

If you have the XVR1 crossover and read Nelson's rather amusing introduction in the owner's manual, I'm sure you saw this:

INTRODUCTION

Some audio products are designed for anybody who can put batteries in a flashlight. This product is not like that.

Some audio products are designed so that you don’t have to study the manual. This product is not like that, either.

Some audio products are designed so that you plug them in and you don’t have to fool around with them for a year before the system is greatly improved....


The XVR1 is a fantastic piece of engineering, but I think you are barking up the wrong tree trying to use the XVR1 crossover for room correction.

[substance]

I don't want to sound rude but I already mentioned I have an ECE degree, I took all of the analog(microelectronics, power, sensors etc), both discreet and continous time, and some rf courses(and some more). I have been building/desiging such circuits for about a decade now. I am pretty confident Nelson's introduction does not apply to me.

I want to make it clear again. I don't expect ruler flat curves you would accomplish with a digital dsp. I can remove heavy nulls and peaks with the xvr1. Room eq in essence is the same thing as xvr1 written in software and many of them. If you already have a digital signal, by all means digital processing is better. No phase issues, you can have many polls and zeros, literally zero distortion. But I want to keep my analog sources in analog.

I respect some folks like to buy a product that already sounds good out of the box or pay for someone to calibrate it for them. At the end they are only interested in the good sound. I like the good sound too but calibrating, modifying, tweaking my electronics is part of that joy for me.

[Mctwins]

I totally agree with GaryProtein.

Don't forgett how your room acoustics behave. If you have room modal resonances, this can never be EQ. Even if you get flat freq response curve in the room.

Look at this video, very interesting.

https://youtu.be/zrpUDuUtxPM

[substance]

Why are we talking about room eq? Do you see in any of my original post, I mention room eq? Xvr-1 specifically sits under active xover sub-header. Once Garry started questioning my reasoning on such project, i used the word semi room eq, I should have perhaps say kinda room eq. Anyways I never intended to emphasize on room eq, well we taked about it, lets agree to disagree on the xvr-1. Can we go back to the original question?

[GaryProtein]

Originally Posted by substance

Why are we talking about room eq? Do you see in any of my original post, I mention room eq? Xvr-1 specifically sits under active xover sub-header. Once Garry started questioning my reasoning on such project, i used the word semi room eq, I should have perhaps say kinda room eq. Anyways I never intended to emphasize on room eq, well we taked about it, lets agree to disagree on the xvr-1. Can we go back to the original question?

Because you said you wanted to use the crossover poles to flatten the response--that is room correction,

A crossover is not the right tool for the job.

You said:

Currently its in 2-way, just the sub and towers. I don't know if you are familiar with the continues time signal processing in ece but 4 poles are sufficient to flatten out the response of these line source speakers in a relatively flat room. I prefer to deal in room correction with acoustic treatment for mid to highs and analog equalizer for the very lows.(low frequencies are too strong to compensate with 2-3" thick absorbers). Within 300-60 (bandpass), you can flatten that region with 4 poles. Sure digital room correction in discrete time with many poles would make it ruler flat but I prefer to stay in continues time.

For correcting the response, you don't need to use all the poles on xover points. You can try placing one or two poles on the very bottom (22hz or 36Hz) should significantly flatten the response of the bass panel up to mid regions, another pole or two on the other side (330Hz or 360Hz). In 3 way, you have 12 poles with the xvr1. If you set it up properly, you can remove nulls and significant peaks. You will be left with 1-2db fluctuations in the longer bands but anything under 3db is indistinguishable to human hearing. It's a lot of work, like tens of hours of calibrating perhaps (digital room eq does this in minutes) but that's ok with me. At the end, you are rewarded with never to digitize your signal.

On a second thought, writing a matlab code for playing with the poles would help figure out where to use poles. Matlab code would assume petfect flat response of course but it would help you calculate the curve if you have to place to poles very closely.

[substance]

Ok garry, you win.

[John49]

Originally Posted by substance

Ok garry, you win.

Is this now the end of the substance abuse?

[substance]

Originally Posted by John49

Is this now the end of the substance abuse?

Is this question related to my substance addiction?

[GaryProtein]

Originally Posted by Mctwins

I totally agree with GaryProtein.

Don't forgett how your room acoustics behave. If you have room modal resonances, this can never be EQ. Even if you get flat freq response curve in the room.

Look at this video, very interesting.

https://youtu.be/zrpUDuUtxPM

Thank you for this youtube video.

It should be required viewing for all!