LM1875 minimal gain

Or just design a preamp that isnt blasting away for no reason.
The wattage is low. Most would just use a normal passive crossover for a 2 way MI application.
Why Biamp with a 18 watt chip when a normal 30 to 60 watt amp will power the whole thing.

Depending on tweeter if even ideal for bass.
Typical wideband 12" is fine for the application.
Otherwise for less beaming. Your looking at a typical 5 1/4 or 6.5 inch for a " Tweeter"
at the most a 2" dome midrange.
Depending on sensitivity needed.
 
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To reduce system noise of bass guitar for high harmonic content
Cutoff Can be 12 kHz
For anything with high harmonics from distortion
Cutoff can be 6 kHz
Usually done in the preamp.
Depends on filter order. High order recommended for distortion. 3rd or 4th order
If a simple 1st order filter The cutoffs can be lowered significantly
More like 3k distortion 6k for wider bandwidth.

The highest frequency fundamental on a standard Fender neck = 330 Hz
Bass Fundamental Bandwidth in a actual mix/ band mix is actually non directional
So 3rd harmonic is under 1000 Hz 6th Harmonic under 2000 Hz

Most players simply dont notice the difference between a 12" or a 15" for Beaming.
It doesn't even happen.
For Jazz or Slap 8" is really the smallest needed.
So again as mentioned for a " tweeter" at any extreme is a 5 1/4 inch or even just a 6.5 inch speaker.
1 cap 1 coil = all done "HiFi" could be second order.
Twee tards blow up. Dumbest thing ever put in a bass amp.
The attack transient is what blows them.
Most players cant control the attack, so compressor it is.
 
@toulou That's what op wants as specified in first post. He wants tweeter from 2.5kHz. Nothing wrong with that.
I do not play bass guitar, so i am no expert here. I know nothing about slapping tevhniques, or any other. All i know is that even bass guitar produces higher harmonics, so besides the woofer in bass cabinet, it needs the tweeter.
 
I have the amp almost finished, it is designed with active crossover and a separate tweeter volume.

I have the lm1875 pcb finished and mounted, so only ad hoc tweaks on the existing pcb are possible.
  • either the feedback resistor cap - gain stability problems?
  • or the input network tweak (1k/330p)
Then I wanted to limit the hiss that comes when you turn up the EQ highs (both onboard bass and the amp's EQ)

I have the tweeter already. A passive LPF would require at least some power resistor in series with a cap, both across the tweeter.
Or series inductor (don't have)/ parallel cap.

But why doing that if I can LPF the signal beforehand?

2k5 tweeter HPF is chosen by specs, the mid- bass speaker is supposed to go around there.
It could be tweaked, but the noise is more annoying.

The amp EQ highest band is ~6-7k and I do hear tonal difference tweaking it.
 
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