Condenser in tweeter line with active crossovers???

[wwwn]

I am in process of building 4way, precisely 2x active, with 2x passive. And wondering if I must have some kind of crossover before horn and tweeter? Maybe condenser of 14uf (1500hz,8ohm) or so in line for the case of 50/60hz humming or dc impulses when amp is turning on/off or in case of bad connection? Putting tweeter directly on an amp don't seems too smart for me...

 

[Charles Darwin]

I've been using my 4way actives for a number of years now.
They have a compression tweeter and the amp driving it right now does produce a turn-on thump but even without a cap it has never been a problem whatsoever.

On the other hand I also use a ribbon supertweeter which I protect with an 18dB/oct high pass (5kHz, the ST kicks in at 12kHz).

 

[bobodioulasso]

I use 50uf serial connected to my active filtered tweeters to protect them without interfering with the crossover.

 

[wwwn]

@Charles, Bobodioulasso
Thanks for answers...
Next.. If I decide to put condenser, it will make 90o phase shift... than, I should use inductor in woofer line to get opposite 90o for 180o difference for connection with opposite polarity?

 

[sreten]

@Charles, Bobodioulasso
Thanks for answers...
Next.. If I decide to put condenser, it will make 90o phase shift...
than, I should use inductor in woofer line to get opposite 90o for 180o
difference for connection with opposite polarity?

Hi,

No. There is no phase shift in the active region of
the tweeter if you use a decent sized capacitor.

rgds, sreten.

 

[Charles Darwin]

Just make sure that the capacitor which protects your tweeter has its -3dB point AT LEAST one octave below where your tweeter actually kicks in.

That is to say that if your tweeter does 5kHz and up the protection cap should roll off everything below 2.5kHz

 

[bobodioulasso]

Not only the cap will protect the tweeter but also null the dc offset of the amplifier (wether there is some) allowing the tweeter to remain centered at his rest position, avoiding unwanted distortion.

 

[wwwn]

Thanks to all

there is my idea about crossovers in lo and hi active channels. What do you think?
There is no zobel or sensitivity compensation, this my is first concept.
How zobel should looks like for this configuration?
I have no much data about drivers...
What kind of box to make? I thought about compression boxes for both bass drivers - apr 40-50l for woofer and 10-15l for bass/mid...

 

[bobodioulasso]

Which drivers are these?

 

[wwwn]

ex Yugoslav, Ei nis... not to bad
I have them 15 years, its last minute for DIY))))

 

[bobodioulasso]

Personally, i would make it simpler: two ways active.
12" + horn. (about 60liters)

 

[wwwn]

Personally, i would make it simpler: two ways active.
12" + horn. (about 60liters)

I have information about this 12".. nice but soft bass. My idea is to make reference monitors for studio and i need tight bass around 200hz for bass guitar and drums kick. At the other hand, horn goes to 16khz.. good but maybe it is better to have dedicated tweeter for highs over 10k?

 

[wwwn]

I am wondering if this woofer have to be in the vented box? What are apr measures of such hole?
@bobodioulasso
I will give it try... good idea

 

[bobodioulasso]

Using quickly Winisd beta , you can see volumes and bass response for a vented box and a closed one.
vent diameter and length, ( not shown) i read
diameter: 0.102m
lengh: 0.169

These are rough results that you can optimise downloading Winisd beta and entering Fs, Vas and Qts.

 

[wwwn]

Using quickly Winisd beta , you can see volumes and bass response for a vented box and a closed one.
vent diameter and length, ( not shown) i read
diameter: 0.102m
lengh: 0.169

These are rough results that you can optimise downloading Winisd beta and entering Fs, Vas and Qts.

Thank You, very useful tool