THE Crossover Thread

AngrySailor

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---not quite right
#48
How would we look at and measure phase? I assume we're talking about the AC electrical waves in the speaker wires not having the same "timing"? Or?
I THINK, the issue is varying phase shift over a frequency range which a blanket delay couldn’t compensate for? As Gibsonian posted, how much worse is it compared to passive? Would narrower bands/more channels help control this? I’m running two way active in the shop with three way passives on the upper frequency amp/cabinets. In the house I’m trying to run three way active, with one passive network splitting the mid and tweeters. Linda receives 500hz and up, the passive splits the mid and tweeter at 3.5khz.
 

laatsch55

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Halfbiass...Electron Herder and Backass Woof
#49
Any electronic component messes with phase coherency.. or phase shift..It's frequency dependant...The AP I have measures phase lag/lead...a WOPL will have the high frequencies leading the lower frequencies by 7 degrees IIRC??? All equipment has some sort of phase shift....and I'm about to get corrected.....I just know it. And the bad thing is...the ears and the brain are very sensitive to it....you might not be able to explain it or know it for what it is .....but you know something ain't right. It gets worse as your slope gets steeper.. a 6db/oct Butterworth filter sounds much better to the ear than a Linkwietz/Riley filter at 48 db/oct. Why are things like this.....that's where Joe comes in...
 

J!m

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#52
My understanding of phase shift as it applies to us is each speaker in a multi driver arrangement not moving in unison.

so, some frequencies arrive later than others. Typically low frequencies are late. The slopes baffle of Thiel and staggered placement of the Vandersteen were done to try and retain time coherence of the arriving signal.

They also both have very complex crossovers to deal with first order shift to successive drivers as well as keeping phase as true as possible electronically.

The physical and electrical need to work well together to make a speaker that lets you suspend disbelief.

This is no small feat.
 

laatsch55

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#54
That was a good read...starting to get th a small inkling of understanding...
I think we are lucky that anything coming through the speakers doesn't send us running from the room screaming
 

George S.

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#56
Received the MiniDsp 4X10 HD. A very clean unit.
I contacted Support with the units serial number, and within the hour they activated the software plugin download on my Support page for free, no charge. They've always impressed me with their online support.
The unit has internal jumpers and switches for selecting input and output gain structure.
Input unbalanced sensitivity can be set to 0.9V or 2V RMS.
Output unbalanced gain can also be set likewise to 0.9V or 2V RMS.
There are similar gain structure settings for the balanced inputs and outputs.
I'll be using the unbalanced RCA inputs and outputs.
Going to open her up and set the gain structure to it's lowest sensitivity and output gain setting. I'll get her up and running in a 2X4 configuration for the JBLs and stereo subs, and see how it compares to my ancient MiniDsp 2X4, and experiment with the gain structure.
Been listening to FM Classic Rock all day on the PL5100 S2 tuner. Spent the morning watching those DUST short scifi films on YouTube that Fred posted. Excellent and thought provoking.
 

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George S.

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#57
The 4X10 HD unit is a improvement over the old 2X4. This is going to work well even though MiniDsp considers it a "legacy device" now since it's so old.
Tomorrow I'll dig in the parts and see if I have Budwig feet for it.
Damn the tinnitus that's been really bad today.
 

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Mohawk

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#59
The 4X10 HD unit is a improvement over the old 2X4. This is going to work well even though MiniDsp considers it a "legacy device" now since it's so old.
Tomorrow I'll dig in the parts and see if I have Budwig feet for it.
Damn the tinnitus that's been really bad today.
The 4x10 HD is out of production and has been replaced by the flex series.
Apparently a dramatic improvement in the AD converter.
The reviews I have read tend to agree.

https://www.minidsp.com/products/minidsp-in-a-box/minidsp-flex-eight
 
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