1uf or 2uf for helper tweeter

[bigwill]

I have some drivers that go up to about 15Khz and need a bit of help above that. A lot of people say use a 1uf cap to cross at 10Khz (for 8 ohms) but the calculations say a 1uf cap puts the xover freq at 20Khz, but 2uf is 10Khz. Should I use 1uf or 2uf for a helper tweeter? I have a lot of 1uf metal film caps, will these work? Thanks

[sreten]

Originally posted by bigwill
I have a lot of 1uf metal film caps, will these work? Thanks

Yes they will, so try one or two with the helper tweeter.

/sreten.

[bigwill]

Done

WOW, what a difference!!!!

[bigwill]

This is the first time the entire spectrum of my system is covered by DIY speakers! This cheapy mess of drivers sounds better than my mordant shorts running > 80Hz did!

I don't understand why the treble sounds so much better than on my supposed "hi-fi" speakers. Cymbals now sound like bits of metal instead of a generic TSSSss sounds. Very odd. The tweeters cost about 5 pounds each!

[Godzilla]

1uf provides -6db at about 20k.

http://www.zillaspeak.com/Crossover.asp


This means it's gradually blending into the full ranger you have. Sometimes you might want to use an L-pad to further adjust the volume of the tweeter for an even better match if needed.

I love super tweeters. The cheaper the better!

Godzilla

[bigwill]

It seems to blend pretty well. The level is about right luckily since it roughly matches the full ranger's efficiency. Hopefully there isn't too much of a hole in the trebel response.

[zobsky]

Originally posted by bigwill
This is the first time the entire spectrum of my system is covered by DIY speakers! This cheapy mess of drivers sounds better than my mordant shorts running > 80Hz did!

I don't understand why the treble sounds so much better than on my supposed "hi-fi" speakers. Cymbals now sound like bits of metal instead of a generic TSSSss sounds. Very odd. The tweeters cost about 5 pounds each!

congratulations!, TL subwoofer + widerange + helper tweeter is a good way to go.

you might be surprised at how cheap the components in many "hi-fi" speakers really are (and also how compromised commercial designs often are), hence the whole diyaudio thing

be sure to check that your tweeters aren't running several dB louder than the rest of your system (and in general that your system has a balanced response. there are several shareware RTA audio analysis programs out there

[Landroval]

Originally posted by bigwill
I have some drivers that go up to about 15Khz and need a bit of help above that.

May I ask what driver are you using?

[bigwill]

Originally posted by zobsky


be sure to check that your tweeters aren't running several dB louder than the rest of your system

Is it possible for this to happen and go unoticed? I don't want to be blasting my ears with loud 20Khz all the time! I'm 18 so my earing still goes that high and I don't want to mess it up with some badly integrated tweeters I have a bad feeling they're too loud actually... turning the treble down on my preamp gets rid of the treble quite a lot - but it's not completely gone like on my other speakers. The treble set to +0 sounds good, possibly rather bright.

[zobsky]

Originally posted by bigwill


Is it possible for this to happen and go unoticed? I don't want to be blasting my ears with loud 20Khz all the time! I'm 18 so my earing still goes that high and I don't want to mess it up with some badly integrated tweeters I have a bad feeling they're too loud actually... turning the treble down on my preamp gets rid of the treble quite a lot - but it's not completely gone like on my other speakers. The treble set to +0 sounds good, possibly rather bright.

even if your hearing goes out to 20KHz, chances are it's not going to be as sensitive at that frequency as say, 1000Hz.

if you have the T/S specs for the drivers, you could compare the efficiency of the widerange and the tweeter to guestimate if you might have a mismatch.

from there, experiment, ... a small resistor is a simple way to pad down the output ot a driver, if needed. google up for more info