Ignorant capacitor question....

[Coytee]

As you likely know, I use an active....  however, I DO have passives on my LaScalas but the twist is, none of what I own creates this question in me.  It just dawned on me and I'm a curious type.

 

So, if a capacitor helps to block low frequencies, if it's doing its job correctly then you won't hear "X" frequency.  (by the way, if I'm backwards a bit on the capacitor, my question still applies to it for whatever it does)

 

Back to question....  if it's doing its job correctly, then it will block the low frequencies and "you won't  hear them".  Now, let's change the grade of capacitor from an entry brand to an esoteric " high quality" (high price) variant....  if it blocks the same frequencies and you still "don't hear them" then what is the improvement the higher quality unit gives you?  

 

Not trying to start any issues.....but with this Covid in our air, we could perhaps use a good thread or two on tubes/SS, passive/active....  

 

It is however, a genuine curious question I have....  if I successfully block "X" frequencies, then what improvement does a fancier version bring to my table?  How does it block those signals better?  Doesn't blocked equal blocked?  (not to be confused with calling me a blockhead)

 

I would like your report to be two pages, double spaced and presented in the third person.  

[jimjimbo]

Capacitor performance completely depends on the speaker, interconnect and power cables you are using, and whether you are using either quartz or Australian black walnut risers under all of those cables.  And of course, whether you have a dedicated 20 amp power circuit supplying your system.  Geez, I would have thought you would know all of this by now......

[Coytee]

I only have access to Pine... and where I live, is about 20 years behind society.  We just had in the local paper that President Reagan was shot???  I hope he's ok?

 

 

 

[seti]

4uf will block the same no matter what manufacturer. Now there are caps with tolerences from 20% to 1%. The weird thing is the higher end the cap or the more boutique the higher the tolerence. Does it matter how close to the prescribed freq you are?

[Wirrunna]

Well, I might be able to help you with Australian black walnut, or black sally wattle, black jarrah, black gum tree wood of all 101 varieties from the east coast - in fact most trees for a couple of hundred miles from my place are black due to the bush fires last christmas.

 

As far as capacitors go, this article - http://www.reliablecapacitors.com/oldRC/www.reliablecapacitors.com/pickcap.html

was one of the first to really get into the nitty gritty and worth a read.

[Edgar]

Also keep in mind that the only "frequency" that capacitors block is DC. All the others are attenuated; the lower the frequency the greater the attenuation.

 

Same applies to inductors, except in the opposite direction. Inductors pass DC and attenuate other frequencies; the higher the frequency the greater the attenuation.

 

It's all part of the Grand Plan. 

[jason str]

Its quite common for individual driver variances from 5% to as high as 20% .

 

Unless your drivers have been measured and hand matched to form a set i would not sweat it much.

[jimjimbo]

45 minutes ago, jason str said:

Its quite common for individual driver variances from 5% to as high as 20% .

 

Unless your drivers have been measured and hand matched to form a set i would not sweat it much.

Driver variances of what?  Sensitivity, SPL, etc, etc?

[Coytee]

You all need to dumb it down a bit...

 

and also, lest someone think I'm trolling....  I don't really care what the answer is, I'm merely a curious type and this has me wondering.  So, in that vein, let me give an analogy.

 

My door is on hinges.  They allow my door to swing shut.  Once it's shut.....it's shut.   At that time, I don't care if my hinges are brass, copper, gold or anything else as regardless of their finish, they did their job of closing the door.  A different finish didn't close the door any faster or tighter....  they simply allowed it to swing closed.

 

So, if a capacitor (and pardon my liberal use of loose understanding here)....  so, if a capacitor shuts down the sound at 400 Hz....the sound is shut down.  Much like my door being closed.  If we compare two extremely different capacitors what does the one extreme do better/worse than the opposite extreme if BOTH of them shut the signal/door at 400 hz (or whatever it might appropriately be)

 

In your spare time, you all meander about new amps, cars, women....something exciting.  I get curious about something like this and I use an active.

 

Go figure.

[Alexander]

23 minutes ago, jimjimbo said:

Driver variances of what?  Sensitivity, SPL, etc, etc?

 

Have done impedance sweeps on many drivers and they never seem to be exactly the same within the same model.

[Alexander]

 

Here is one:

'ESR adds DC resistance – effecting the charge/discharge rate in the circuit they are in. In other words how fast they react to change in frequency. The greater the ESR the slower the cap responds.

[carlthess40]

Is there a chart somewhere that would tell me what the crossover point is for any given capacitor and resistor in both 8 and 4 ohms?
I have a set of diy 2way towers that have one 8 ohm tweeter and two 8ohm woofers
I don’t really know how to Design a crossover but I do know how to rebuild them, and when rebuilding them you just follow what’s there so any help would be much appreciated and sorry to step on your post. But very good and valid question to best and I’d like to know these answers as well


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[mboxler]

14 minutes ago, carlthess40 said:

Is there a chart somewhere that would tell me what the crossover point is for any given capacitor and resistor in both 8 and 4 ohms?
I have a set of diy 2way towers that have one 8 ohm tweeter and two 8ohm woofers
I don’t really know how to Design a crossover but I do know how to rebuild them, and when rebuilding them you just follow what’s there so any help would be much appreciated and sorry to step on your post. But very good and valid question to best and I’d like to know these answers as well


Sent from my iPhone using Tapatalk

 

I use this for capacitors  http://www.pronine.ca/capimp.htm and this for inductors http://www.pronine.ca/indimp.htm

 

Just enter the "resistor" value in the impedance field and it will calculate the -3db frequency.

 

 

[OO1]

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[OO1]

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[muel]

4 hours ago, Coytee said:

I only have access to Pine... and where I live, is about 20 years behind society.  We just had in the local paper that President Reagan was shot???  I hope he's ok?

 

 

 

The newspaper I found in the trunk of my Chrysler Newport said Nixon was going to China... hope he stays well!  

Reagan?!  You mean the actor turned governor?

[Alexander]

23 minutes ago, Randyh said:

NO KIDDING ---

Was that really necessary? My post was directed to the question by the OP.

[babadono]

I'm not big on esoteric capacitors. Maybe when I was younger with much more acute hearing I could have gotten excited about such, I don't know. But....... there are other things at play here not just the "capacitance" of a capacitor. ESR has already been mentioned. there is also parasitic inductance. And I'm sure there are more.

[OO1]

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[MC39693]

I understand ESR at least conceptually, I think I took electricity and magnetism in university... but, my question is where is the “as installed” ESR value documented? The oil can capacitors I replaced in my Heresy E crossover had their capacitance value on them as does the documentation for an E crossover but not the ESR value. Yes I could check all 4 (2 per crossover) and subjectively say yeah they are all close or one is out? If I don’t have the original intended value am I changing the crossover performance when I didn’t intend to even though I match the capacitance value? Newer technology surely changes the performance some how?

 

I’ve only done 3 sets of crossover builds / major changes. I too have “old” ears. But I did convince myself I could hear a reasonable difference using only pretty ordinary capacitors.

 

I have seen seen some masterful crossover builds here and appreciate the time, effort and skill. I like to learn from others. I just have a tiny budget?