Menu

Post image 1
Post image 2
1 / 2
0

We Eliminated EQ Frequency Cramping Without Oversampling — Here's How (DAFx26 Paper)

DEV Community: cpp·Gary Doman/TizWildin·3 days ago
#paOU3lE9
Reading 0:00
15s threshold

We Eliminated EQ Frequency Cramping Without Oversampling If you've ever pushed a parametric EQ boost to 16 kHz and wondered why the curve looks wrong — you've hit frequency cramping . Traditional biquad filters using the bilinear transform exhibit 199% Q distortion at 16 kHz (44.1 kHz sample rate). The filter becomes almost 3× narrower than intended. The industry solutions? Brute-force 4× oversampling (adds latency, burns CPU) or proprietary analog-matching curves (FabFilter's approach, closed-source). We took a third path: the Simper State Variable Filter (SVF) . The Results Topology Magnitude at 16 kHz Error RBJ @ 44.1 kHz +0.73 dB −5.27 dB (cramped) SVF @ 44.1 kHz +6.00 dB 0.00 dB (exact) RBJ @ 4× Oversampling +4.82 dB −1.18 dB The SVF achieves exact gain at the center frequency — no oversampling, no proprietary tricks. How It Works The SVF pre-warps the cutoff frequency: g = tan(π · fc / fs) Enter fullscreen mode Exit fullscreen mode This single line eliminates the bilinear transform's frequency warping.…

Continue reading — create a free account

Join HashtagPLUS to read full articles, follow hashtags, vote, and join the conversation.

Read More