| General > General Technical Chat |
| band pass filter for an audio application |
| (1/5) > >> |
| Coordonnée_chromatique:
Hello, I'm trying to design a band pass filter for an audio application and i'm curious to have you advices on audibility of an eventual quality degradation that i haven't thinked about because i'm not a secialist at all. |
| TimFox:
For large capacitors, e.g. 1 uF, the type of capacitor may be important. Polypropylene film is the usual "good choice", with very high Q and therefore low ESR, but X7R and Z5U ceramics will have substantial loss and nonlinearity. |
| jonpaul:
Bonjour cher Monsieur bon pour vu un français à la forum eevblog SVP me préciser votre application et requirements The two pole bessel is perhaps a bad choices eg ADC, DAC antialiasing, Cordialement Jon |
| Benta:
Ain't no such thing as a "Bessel" band-peak filter (band-pass is something else in my book, particularly for audio). The only thing that matters here is fc and Q. You apparently need a low Q filter. Sallen-Key is OK for that. For higher Q, I recommend using a MFB filter instead. |
| dmills:
Not I suspect going to work! The TLV2405 has all of 5kHz GBP, and a few mA of output drive, and you have an 80 ohm resistor in the filter feedback path (With 1uF to ground??!)? Sallen and Key topologies are notoriously 'interesting' once the opamp runs out of GBP so I would at least be opening the plot out to see what happens in the top couple of octaves (The lowpass version of things have a bad habit of coming back once the opamp is out of puff). |
| Navigation |
| Message Index |
| Next page |