Adding a tweeter to full range

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OK, you seem to have found the best solution finally.

Integration of a second tweeter on the rear seems
to be tricky because freq response of the fullranger
is very different between front and rear.

Having a fairly large fullranger and the rear tweeter
having same crossover slope as the front tweeter
i can imagine there is nothing to win concerning
homogeity, especially because the XO frequency
on the rear would have to be much lower
than that of the front tweeter .... which in
turn can make the rear tweeter more detectable if
too loud.

With asymmetric crossover again there is a frequency
dependent phase shift between the tweeters.

So i feel my own good experience with rear filler
tweeters is restricted to smaller fullrangers on narrow
baffles, where there is "nothing to complain" in the highs
radiated to the front.

So finally i have learned from your experimenting too ...

Kind Regards
 
frugal-phile™
Joined 2001
Paid Member
What FR? What tweeter?

Usually the impedance rises as frequency goes up.

On the super-tweeter the cap causes the impedance at low frequencies to get very high...

so at most frequencyies the impedance is ~4 ohns in parallel with a very big R = ~4 ohms.

As probably mentioned earlier in the thread their are 2 techniques for attenuating a more efficient tweetr 1/ series R (or an L-Pad), or 2/ XO higher than nominal and let the 1st order slope of the XO bring the tweeter level down.

dave
 
FR: chr-70
Tweeter: ApexJr Ribbon Tweeter (4ohm version)
The tweeter will be crossed >15000 Hz and it's purpose is to give a wider high frequency response. The chr-70 goes high enough but the hights are, in my experience, very on axis dependent. Someone earlier in the thread mentioned the expression "filler tweeter". I think thats what I'm thinking of.

So what you're saying is that adding the tweeter in parallel would not lower the overall impedance that much?

Regards H@kan
 
Hi,
i want to use a Monacor RBT-95 SQ on top of my Speaker, W4-1320.

dzu48662.jpg


can it works?
 
frugal-phile™
Joined 2001
Paid Member
FR: chr-70
Tweeter: ApexJr Ribbon Tweeter (4ohm version)
The tweeter will be crossed >15000 Hz and it's purpose is to give a wider high frequency response.

As can be seen in the link, that ribbon only goes up to 15k... this apexJr tweeter is probably better for the application.

ApexTweeter1.jpg


Buy a whack, they are really useful to have kicking around.

Attached is the measured impedance of a CHR-70. The roll-off at the top is the measurement kit, the driver continues its slow rise. Where you plan on XOing it is ~ 7 ohms.

dave
 

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I will definitely buy a bunch of them. Looks useful.
I tried the ApexJr Ribbon Tweeter in parallel with the chr-70 with 2x2.2uF in series=1.1uF right? caps on the tweeter. The hights are now wider and i'm not restricted to just one of the seats in the couch :).

Regards Håkan
 
Hi. interesting topic. I have a pair of Tang Band W8-1772 which they are very good in high freq. I would like to experiment to add a tweeter crossed very high, +15000 Hz or so. My question is if it is necessary to get a expensive tweeter if it will be used so high. And may be the most important is to look the sensitivity and the freq response maximum?
 
Interesting thread.

I am thinking of adding a tweeter to to my fullrange driver. I have been reading this web site Series vs. Parallel Crossover Networks and I am having a little difficulty getting my head round the cicuit diagram for the 1st order filter in series. It looks wrong to me. Wouldn't the harmful low frequencies bypass the capacitor and go direct to the tweeter causing damage ? The parallel configuration makes sense.

I'd like to implement a series 1st order crossover configuration with no inductor. The drivers in question are the Fostex F120a (8ohm, 89db 1watt) and Vifa xt25 (4ohm 91db 2.83v). I'm not sure if i'll need to add an L-pad to the tweeter ?

I would add capacitance until I reach the preferred sound.

Any feedback would be much appreciated
 

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frugal-phile™
Joined 2001
Paid Member
... am having a little difficulty getting my head round the cicuit diagram for the 1st order filter in series. It looks wrong to me.

That circuit is correct. Low frequencies are shunted across the choke, away from the tweeter (leaving just HF) and the HF are shunted by the cap past the woofer (leaving just the LF)

dave
 
Hi All,

Am trying to revive an old thread here.

I am building a 2.1 boom box using a 2.1 TPA3118 based amp which puts out 30W x 2 for the Satellites/FR and 60W x1 for the Subwoofer. There is a crossover built into the amp for the Subwoofer from 30Hz to 150Hz. There is no built in HPF for either the Sub or the FRs.

I am using a pair of Dayton Audio RS100-8 (8 Ohm) for Satellites/FR duties with a first order HPF at 100Hz (200 mfd Cap) and a basic BSC comprising of a 0.90mH Inductor and 6 Ohm Resistor in parallel.

The Sub is a Tang Band W6-1139SIF (4 Ohm) with a first order HPF at 33Hz (1200 mfd Cap).

The sound is pretty controlled and coherent. The only thing missing are the topmost frequencies when I compare it with my main system which is a three way system using separates. The difference in the top end is not much, maybe around 10%. To compensate for this I was planning on adding AMT tweeters at top of the speaker (the top back portion). I was needing some 'clarity' with the wire connections for the same.

The earlier posts had suggested wiring the tweeter after the +VE terminal of the FR and adding a Cap to the +VE terminal of the Tweeter (I plan to use a 2 mfd Cap for a 10KHz first order HPF considering a 8 ohm Tweeter). My confusion is with regard to the fact that I have a BSC in place BEFORE the +VE terminal of the FR. How will this affect the high frequencies going towards the Tweeter which is wired AFTER the FR. Do I need to wire the Tweeter some other way?

Thanks in advance.
 
As far as my build is concerned, the two FR Dayton Audio RS100-8 and the Tang Band W6-1139SIF sub are front mounted. The plan is to mount the AMT Tweeters on the top of the speaker box (firing upwards). I hope this will be a better option for dispersion.

The question I have is how do I wire the Tweeters to the FR driver especially since I have the BSC (0.9 mH Inductor and 6 Ohm Resistor) and HPF (200 mfd Caps) before the FR drivers.
 
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