Faital pro build too bright - cross over filter help please!

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Hi all! I just built some 3" ported full range speakers from faital 3fe25's but they are incredibly bright. I hace seen the frequency graph but didn't expect them to be quite so trebly!

I'm a bit confused about how to go about fixing this. I know I need a resistor and a capacitor across the + and - but not sure what values. The driver is 4ohm. I was thinking maybe I should order a few different types of capacitor and swap them out and see what happens. Ideally I think I want to take the 10k area down. What range of caps should I try and what resistor is needed?

Tia.
 
The datasheet of the Faital Pro 3FE25 indeed shows a huge (10 dB) increase at the top end. To reduce only the top end you might want to try putting an inductor in series with the driver to low pass it. 'Bypass' the inductor with a resistor in parallel to reduce it's effect if necessary. The inductor value sets the frequency at which it starts rolling off the highs.

Or alternatively, create a notch filter at say 12 kHz by putting a inductor, capacitor and resistor in parallel and putting the whole in series with the driver. the notch frequency is set by the inductor and capacitor, the amount of cut by the resistor. Download Boxsim, simulate a box with a Visaton FRS8M and experiment with different values to see what frequencies are affected with certain component values.

Example values to start with: 0,33 mH or 0,33 mH / 0,47 µF / 33 ohm.
 
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Ah ha! Thanks! So could I use a pot to vary the resistor value that would set the roll off?

What value resistor range would be useful in this respect? Very eager to try your suggestion!


The datasheet of the Faital Pro 3FE25 indeed shows a huge (10 dB) increase at the top end. To reduce only the top end you might want to try putting an inductor in series with the driver to low pass it. 'Bypass' the inductor with a resistor in parallel to reduce it's effect if necessary. The inductor value sets the frequency at which it starts rolling off the highs.

Or alternatively, create a notch filter at say 12 kHz by putting a inductor, capacitor and resistor in parallel and putting the whole in series with the driver. the notch frequency is set by the inductor and capacitor, the amount of cut by the resistor. Download Boxsim, simulate a box with a Visaton FRS8M and experiment with different values to see what frequencies are affected with certain component values.

Example values to start with: 0,33 mH or 0,33 mH / 0,47 µF / 33 ohm.
 
Founder of XSA-Labs
Joined 2012
Paid Member
BSC is just an inductor and resistor in parallel between amp and driver +ve terminal. No surgery involved :)

524823d1452728991-tabaq-tl-tang-band-image.jpeg
 
Hi all! I just built some 3" ported full range speakers from faital 3fe25's but they are incredibly bright. I hace seen the frequency graph but didn't expect them to be quite so trebly!

I'm a bit confused about how to go about fixing this. I know I need a resistor and a capacitor across the + and - but not sure what values. The driver is 4ohm. I was thinking maybe I should order a few different types of capacitor and swap them out and see what happens. Ideally I think I want to take the 10k area down. What range of caps should I try and what resistor is needed?

Tia.
You dont mention what treatments you did inside the enclosure to minimize the treble acoustical energy, I suppose you did not do anything as usual in these cases, DIYers want resolve an acoustical problem by electronic means as Zobel, filters, capacitors etc
See This thread:
How to Treat Passively Peaky FullRange Drivers
OR THIS:
How Treat Passively Peaky Fullrange Drivers
Due FS 110Hz you will need up the bass response w/the 10mm browm car hood blanket.
Small enclosures will favor mid and hi frequencies and down the bass.
Hope this Help.
image.php
 
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Founder of XSA-Labs
Joined 2012
Paid Member
I have used this driver extensively (3FE25), it is smooth and really pretty much free of annoying peaks. "Too bright" usually means an imbalance of bass relative to treble - usually cured with a shelving filter like a bsc. A "peak" at a certain frequency will not be described as "bright" because it only affects certain sounds and passages that have content at that frequency.

You won't find too many drivers smoother than this except for maybe TC9FD/TG9FD/10F but they are all 86-87dB sensitve and not 90dB.
faitalpro-3fe25-freq-size475.gif


The breakup peak at 12k is angle dependent and smooths out as soon as you are off axis so is not a problem in general.
 
I put a 4" x 3" x 2" slab of rockwool behind the driver. The cabinet is tuned to around 85hz with a 32mm wide port.

You dont mention what treatments you did inside the enclosure to minimize the treble acoustical energy, I suppose you did not do anything as usual in these cases, DIYers want resolve an acoustical problem by electronic means as Zobel, filters, capacitors etc
See This thread:
How to Treat Passively Peaky FullRange Drivers
OR THIS:
How Treat Passively Peaky Fullrange Drivers
Due FS 110Hz you will need up the bass response w/the 10mm browm car hood blanket.
Small enclosures will favor mid and hi frequencies and down the bass.
Hope this Help.
image.php
 
hey i had the same problem with mine even they are a bit different , they are 3 fe 22 the annoying distorsion at heights still occur.

i placed a 1 mH coil in series , then in paralel with the coil a 2 uF capacitor and 22 ohm resistor . it sounds ok for my setup.
But remember **** in **** out , when I play u tube at low fidelity they scream annoyingly again!
 
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