How to change active xover frecuencies

[merlin el mago]

How to change active xover frecuencies of Reckhorm F1 active xover, now the high cut adjustable 30-100Hz, low cut adjustable 50-100Hz.

I want to filter tweeter Seas Millenium TCF002 with a low cut filter 1.000Hz and advice for high cut filter for SS18W8545-00

Attached pics with schematic & manual.

All help will welcome.

TIA

Felipe

 

[AndrewT]

The highlighted resistors are for gain setting.
But these gains are monstrously high @ +9.8dB and +20dB !!!!

The filters are the 8 opamps to the right.

All 8 are unity gain Sallen and Key.

 

[merlin el mago]

Thanks Andrew, how can change the frecuencies? yes the attached schematic is to change the xo for high gain.

 

[merlin el mago]

Technical data:

power supply 230 volts / 50 Hz or 110 volts / 60 Hz
input sensitivity 0.1 - 10 volts / 10 k ohms
satellite stereo signal output + 3 dB / 47 k ohms
satellite frequency response 50 - 40000 Hz -1 dB
satellite high pass, stereo, variabel 50 - 150 Hz / 24 dB
satellite total distortions 0.001 %
subwoofer 2 x mono signal outputs max. 10 volts / 47 k ohms
subwoofer frequency response 15 - 150 Hz -1 dB
subwoofer 2 x mono low pass variabel 40 - 150 Hz / 24 dB
subwoofer total distortions 0.001 %
signal - noise ratio subwoofer and satellites over 95 dB
power consumption with signal input max. 3 watts
power consumtion without signal max. 2.5 watts
width x height x depth (mm) 155 x 48 x 130
weight 0.7 kg

 

[AndrewT]

read up on

unity gain Sallen and Key.

 

[merlin el mago]

Like the linkSallen-Key Low-Pass Filter?

 

[woody]

Active Filters



But it doesn't seem to be all that much like the ones described in
that article but I could be wrong.

 

[merlin el mago]

I got this schematic for Sallen-Key Butterworth High Pass Filter

With the calculator online for 1KHz I got:

Ca 11.25nF
Cb 11.25nF
Ra 20K
Rb 10K

Are these values OK?

The schematic isn't the same like the reckhorn uses....

 

[AndrewT]

C1 = Ca
R19 = Ra
etc.

 

[merlin el mago]

?

 

[AndrewT]

look at the schematics.

 

[merlin el mago]

OK reckhorn schematic now I understand, have I to left R19-22 100K?

 

[merlin el mago]

C1 = Ca
R19 = Ra
etc.

Wich one are Cb & Rb, C3 & R23?

 

[merlin el mago]

Sorry my ignorance the filter sub are also high pass filter?

 

[DF96]

As Andrew says, you have a set of unity-gain Sallen and Key filters - some high pass , some low pass. The circuits are identical to the one in post 8, so what is the problem?

 

[merlin el mago]

Look schematic post 1.

 

[DF96]

I already have. So has Andrew. He has explained what you need to do.

 

[merlin el mago]

Pic post 1 I didn't see any low pass filter.

 

[merlin el mago]

Wich one are Cb & Rb, C3 & R23?

I don't know wich are.

 

[DF96]

Low pass filters are on the right. High pass in the middle. Input gain amps on the left. Can you read a circuit diagram?