Now draw it, then say it
On the grid: draw a high-pass filter with its cutoff between 2 kHz and 4 kHz, mark the cutoff with a cross, and label the axes.
Press and draw across the grid; draw over a part to redraw it. Then press ✕ Cross and tap the bend. Pick a label, then tap where it goes.
Read your line where it is 1 dB down: that is where it leaves the 0 dB line, and it must sit inside the range. To read the cutoff off a printed curve, read where it has dropped 3 dB.
Say it in words
Tick each point your drawing or your words make.
On the paper and in a DAW: the same controls
The names you may meet
| On the paper | On a DAW's filter, such as Live's Auto Filter |
|---|---|
| Low-pass (a high cut) | LP, Lowpass |
| High-pass (a low cut) | HP, Highpass |
| Band-pass | BP, Bandpass |
| Cutoff, in Hz | Freq, Frequency |
| Resonance | Res, Q |
| Slope: 12 or 24 dB per octave | 12 or 24 (also called 2-pole and 4-pole) |
The synth panel is our own drawing, in the exam's names. Its picture and the sound come from the same numbers: a sawtooth riff made here, through a real filter, and every curve on the grid is that filter's own response, so the cutoff sits 3 dB down. The grid is the exam's: 20 Hz to 20 kHz across on a log scale, +20 to −20 dB up. ► Mine plays a filter with your line's features (its type, where it is 3 dB down, the nearer of 12 or 24 dB per octave, and any peak), not your exact line. Laptop speakers lose the lowest notes, so headphones help. Made for a laptop or the whiteboard.