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AES Paper Digest: Audio Capacitors. Myth or reality?

AJ Soundfield

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#21
AJ, audio gear doesn't play by your rules, that you're trying to simplify everything with.
Folsom, audio gear obey the laws of physics, which audiophiles know nothing of.
Further, audiophiles are human and subject to perceptual bias, another thing they know nothing of, or simply deny.

Four of the capacitor materials tested are common in speaker crossovers. You didn't look close because all the bridge residual testing was done in the audio spectrum. Besides I proposed the question why you can't hear the differences, supposedly, based on the paper.
It's not a "paper". It's hobbyist Conrad Hoffman doing some cap measurements. There is zero audibility data there.

I'm not feeling any cheers, as you seem to be combative without looking at what I posted.
That's ok, I'm used to audiophiles screaming victimization when they can't defend their baseless arguments. It's a natural protective scheme to avoid reality.:)

cheers,

AJ
 

NorthSky

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#22
This is a very good subject; if we can have more tests similar to the first one → the same two-way monitor speaker made six times (same exact design) and each one of them with different caps inside. Wow, I feel that it would be a totally new experience for me in trying to tell which one sounds better...but I'm sure there are things to learn from it.
And I bet some speaker's manufacturers do experiment with various caps? We all know that the speaker's crossover is very important...to disappear...leaving no trace of transition but just the perfect blend between all the frequencies of the audio spectrum, in particular @ the three x-over points (3-way speaker) ...A nice smooth frequency response @ each x-over point.
And the drivers are important too; what they can handle and down to where and up to where in advance before their performance become less than optimal.
The x-over slopes too, the exact frequency point, the steepness of the slopes. Is 6dB per octave preferred for smoother transition? Most x-over operates @ 24/12.

Question: What exactly is the role of capacitors in speaker's crossovers?
 
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RayDunzl

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#23
Question: What exactly is the role of capacitors in speaker's crossovers?
In series with the signal they reduce/block the low frequency - as would go to a tweeter.
In parallel with the signal they reduce the high frequency - as going to a woofer.

Lows blocked, left, highs shunted, right:

 

AJ Soundfield

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#24
Question: What exactly is the role of capacitors in speaker's crossovers?
Physically, as Ray shows above.
Mentally, they have potentially tremendous psychological impact, depending on the susceptibility of the "listener", who must know for the "effect" to occur psychogenically.
YMMV.
I use film caps (none of the boutique woo woo stuff) in my filter designs due to the tighter manufacturing tolerances, greater stability over time/longevity...and of course, in no small part, because no one listens blind at home, so the above does have an impact on folks. Some more so than others, with/without cognizance.

cheers,

AJ
 

RayDunzl

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#25
Mine probably looks like this... I undid the screws once, but the back didn't fall off so I gave up.

High Voltage supply top right.

Step-up transformer for the stators, top center.

High pass bottom right, low pass, left.

"If it ain't broke don't fix it." - Ray Dunzl

I see what looks like electrolytics (blue) in the woofer filter, I suppose they have bipolar disorder.





upload_2016-4-24_9-47-54.png
 

AJ Soundfield

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#26
Hmm, I'm surprised they mount inductors non orthogonal, which reduces mutual coupling. Fig 5 or 6 would be my preferred layout, but the way ML has it there is better for durability/shipping!
Yes, I'm sure the susceptible will "hear" those caps in the woofer section...now.
 

Speedskater

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#27
This is a very good subject; if we can have more tests similar to the first one → the same two-way monitor speaker made six times (same exact design) and each one of them with different caps inside. Wow, I feel that it would be a totally new experience for me in trying to tell which one sounds better...but I'm sure there are things to learn from it.
There would be so many uncontrolled variables that you won't learn anything.

Some of the problems would be:
a] No two speaker drivers are truly identical.
b] Positioning the loudspeakers in the exact same position.
c] Long time delays when switching loudspeakers.

A better plan would be to have an external crossover, with a switch that another person could use to select a capacitor.
 

NorthSky

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#28
There would be so many uncontrolled variables that you won't learn anything.

Some of the problems would be:
a] No two speaker drivers are truly identical.
b] Positioning the loudspeakers in the exact same position.
c] Long time delays when switching loudspeakers.

A better plan would be to have an external crossover, with a switch that another person could use to select a capacitor.
That's one good thing I just learned from you right now. And I knew that there would be too many variables in my prior example.
Now we need to test yours. ...Your better plan. That could be a tough challenge, but it's from tough challenges that we learn few more things too, not just from simple easy challenges. :)

* And thx Ray for the answer on the role of capacitors in speaker's crossovers.
 
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