Sallen Key Low Pass Filter, bandpass filter

[Maglatron]

right the problem with loading the wav file is sorted, the spice file was in the wrong directory

 

[Maglatron]

so heres the files of the 6kHz wav and asc, It doesn't look like it's doing the job!

 

[Maglatron]

where does the amp go again is it between the filter and the envelope detector

Hello,

In stead of making a complete series of filters twice, you could add a simple amplifier between the filter and rectifier circuit:
View attachment 61950
That would save you a lot of work.

Bertus

 

[bertus]

Hello,

Yes, the amplifier goes between the filter and detector.

Bertus

 

[Maglatron]

Ok thanks can you tell me how to create 16 bands from 45Hz to 6000Hz logrithmically please?

 

[bertus]

Hello,

When you use a factor of 1.4 between the frequencies, you get the following range:

45 63 88 123 173 242 339 474 664 930 1302 1822 2551 3572 5000 7000

Bertus

 

[Maglatron]

Nice one matey

 

[Maglatron]

so here, how do I set the gain so that the millivolts from the signal is enough to be read by the lm3914
also if you can remind me how to link a power supply to the filter circuit power without connecting with leads I've forgot REF too

 

[Maglatron]

Hello,

In stead of making a complete series of filters twice, you could add a simple amplifier between the filter and rectifier circuit:
View attachment 61950
That would save you a lot of work.

Bertus

 

[Maglatron]

they didn't have the TL074 in the library

 

[Maglatron]

so I have written out all of the combined resistors and the capacitors for the series of frequencies you provide from 45 to 7000 hz took a while may sound stupid because its really novice but what are the type of capacitors in the buffer circuit (they're not polorized)

 

[bertus]

Hello,

The TL072 is the dual version of the TL074.
I have an alternate setup for your spectrum display.
In stead of making 16 amplifiers between the filter and detectors, you could make one amplifier in front of all 16 filters:

Bertus

 

[Maglatron]

ok makes sense what would be a good amplification factor??? thanks oh I just read (3-4 times)

 

[Maglatron]

and what is mixing line signal, left and right??

 

[Maglatron]

In spice, I want to create a point on the buffer called ref, and connect the refs of the filters to it without wires also the same with the 12v power supply I did it before but forgotten how!

 

[Maglatron]

when the original signal is 31.4millivolts and times by 4 only gives 0.1256, and you said that the range is from 0 to 2.4v, 0.1256 is only 5.23% of 2.4 am I missing something here?

 

[Maglatron]

If this +goes to REF where does the negative go to?

 

[bertus]

Hello,

Line level for consumer audio is about 0.9 Vpp:

Line level - Wikipedia

en.wikipedia.org

With a gain of 5 the peak would be about 0.45 X 5 = 2.25 Volts.

The VCC+ is 12 Volts, VCC- is 0 Volts. REF would be 6 Volts.

Bertus

 

[Maglatron]

 

[Maglatron]

oh yes I remember now

Hello,

Line level for consumer audio is about 0.9 Vpp:

Line level - Wikipedia

en.wikipedia.org

With a gain of 5 the peak would be about 0.45 X 5 = 2.25 Volts.

The VCC+ is 12 Volts, VCC- is 0 Volts. REF would be 6 Volts.

Bertus

and how do you set it to 0v again?