only frequency test left + description

src/dsp/node_ad.rs

@@ -2,11 +2,11 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{sqrt4_to_pow4, TrigSignal, Trigger};
 use crate::dsp::{
     DspNode, GraphAtomData, GraphFun, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom,
 };
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{sqrt4_to_pow4, TrigSignal, Trigger};
 
 #[macro_export]
 macro_rules! fa_ad_mult {

src/dsp/node_allp.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::AllPass;
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::AllPass;
 
 /// A simple amplifier
 #[derive(Debug, Clone)]

src/dsp/node_biqfilt.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::*;
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::*;
 
 #[macro_export]
 macro_rules! fa_biqfilt_type {

src/dsp/node_bosc.rs

@@ -2,11 +2,11 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::PolyBlepOscillator;
 use crate::dsp::{
     DspNode, GraphAtomData, GraphFun, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom,
 };
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::PolyBlepOscillator;
 
 #[macro_export]
 macro_rules! fa_bosc_wtype {

src/dsp/node_bowstri.rs

@@ -2,11 +2,11 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{DelayBuffer, FixedOnePole, Biquad};
 use crate::dsp::{
     denorm, denorm_offs, inp, out, DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom,
 };
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{Biquad, DelayBuffer, FixedOnePole};
 
 // Bowed String instrument oscillator
 // Bowed string model, a la Smith (1986),

src/dsp/node_comb.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp;
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp;
 
 #[macro_export]
 macro_rules! fa_comb_mode {

src/dsp/node_cqnt.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{ChangeTrig, CtrlPitchQuantizer};
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{ChangeTrig, CtrlPitchQuantizer};
 
 #[macro_export]
 macro_rules! fa_cqnt {

src/dsp/node_delay.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{crossfade, DelayBuffer, TriggerSampleClock};
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{crossfade, DelayBuffer, TriggerSampleClock};
 
 #[macro_export]
 macro_rules! fa_delay_mode {

src/dsp/node_formant.rs

@@ -69,14 +69,17 @@ impl DspNode for Formant {
             let decay_freq = denorm::Formant::dcy(decay_freq, frame);
 
             // where the two decays meet
-            let carrier_center = attack_freq / (attack_freq + decay_freq);
+            // clamp to avoid division by 0
+            let carrier_center =
+                (attack_freq / (attack_freq + decay_freq)).max(1e-6).min(1.0 - 1e-6);
 
             // where they meet in amplitude
-            let carrier_lowest_amplitude = if carrier_center * decay_freq > base_freq * 2.0 {
-                0.0
-            } else {
-                (-(std::f32::consts::PI * carrier_center * decay_freq) / base_freq).exp()
-            };
+            let carrier_lowest_amplitude =
+                if carrier_center * decay_freq > base_freq * 2.0 || base_freq == 0.0 {
+                    0.0
+                } else {
+                    (-(std::f32::consts::PI * carrier_center * decay_freq) / base_freq).exp()
+                };
 
             // make a triangle wave, with the peak at carrier center
             let carrier_base =
@@ -88,17 +91,22 @@ impl DspNode for Formant {
                     * (carrier_base * carrier_base * (3.0 - 2.0 * carrier_base)));
 
             // multiple of the frequency the modulators are at
-            let multiple = formant_freq / base_freq;
+            let multiple = formant_freq / base_freq.max(1e-6);
 
             // round them to the closest integer of the formant freq
-            let freq_a = multiple.floor().max(1.0);
+            let freq_a = multiple.floor();
             let freq_b = freq_a + 1.0;
 
             // and how much to lerp between them
-            let blend = multiple.max(1.0).fract();
+            let blend = multiple.fract();
 
             // get the true modulator
-            let modulator = (1.0 - blend) * (std::f32::consts::TAU * self.phase * freq_a).cos()
+            let modulator = (1.0 - blend)
+                * if multiple < 1.0 {
+                    0.0
+                } else {
+                    (std::f32::consts::TAU * self.phase * freq_a).cos()
+                }
                 + blend * (std::f32::consts::TAU * self.phase * freq_b).cos();
 
             // entire wave

src/dsp/node_mux9.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::Trigger;
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::Trigger;
 
 #[macro_export]
 macro_rules! fa_mux9_in_cnt {

src/dsp/node_noise.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::Rng;
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::Rng;
 
 #[macro_export]
 macro_rules! fa_noise_mode {

src/dsp/node_pverb.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{DattorroReverb, DattorroReverbParams, crossfade};
 use crate::dsp::{denorm, DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{crossfade, DattorroReverb, DattorroReverbParams};
 
 pub struct DatParams {
     frame: usize,

src/dsp/node_quant.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{ChangeTrig, Quantizer};
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{ChangeTrig, Quantizer};
 
 #[macro_export]
 macro_rules! fa_quant {

src/dsp/node_rndwk.rs

@@ -2,9 +2,9 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{Rng, SlewValue, Trigger};
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{Rng, SlewValue, Trigger};
 
 /// A triggered random walker
 #[derive(Debug, Clone)]

src/dsp/node_sampl.rs

@@ -2,10 +2,10 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{cubic_interpolate, Trigger};
 use crate::dsp::{at, denorm, denorm_offs, inp, out}; //, inp, denorm, denorm_v, inp_dir, at};
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{cubic_interpolate, Trigger};
 
 #[macro_export]
 macro_rules! fa_sampl_dir {

src/dsp/node_scope.rs

@@ -8,12 +8,12 @@
 // Copyright by Andrew Belt, 2021
 
 //use super::helpers::{sqrt4_to_pow4, TrigSignal, Trigger};
-use synfx_dsp::CustomTrigger;
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::SCOPE_SAMPLES;
 use crate::nodes::{NodeAudioContext, NodeExecContext};
 use crate::ScopeHandle;
 use std::sync::Arc;
+use synfx_dsp::CustomTrigger;
 
 #[macro_export]
 macro_rules! fa_scope_tsrc {

src/dsp/node_sfilter.rs

@@ -2,13 +2,13 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
+use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
+use crate::nodes::{NodeAudioContext, NodeExecContext};
 use synfx_dsp::{
     process_1pole_highpass, process_1pole_lowpass, process_1pole_tpt_highpass,
     process_1pole_tpt_lowpass, process_hal_chamberlin_svf, process_simper_svf,
     process_stilson_moog,
 };
-use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
-use crate::nodes::{NodeAudioContext, NodeExecContext};
 
 #[macro_export]
 macro_rules! fa_sfilter_type {

src/dsp/node_sin.rs

@@ -2,11 +2,11 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::fast_sin;
 use crate::dsp::{
     denorm_offs, inp, out, DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom,
 };
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::fast_sin;
 
 /// A sine oscillator
 #[derive(Debug, Clone)]

src/dsp/node_test.rs

@@ -2,11 +2,11 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::TrigSignal;
 use crate::dsp::{
     DspNode, GraphAtomData, GraphFun, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom,
 };
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::TrigSignal;
 
 #[macro_export]
 macro_rules! fa_test_s {

src/dsp/node_tseq.rs

@@ -2,10 +2,10 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{Trigger, TriggerPhaseClock};
 use crate::dsp::tracker::TrackerBackend;
 use crate::dsp::{DspNode, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom};
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{Trigger, TriggerPhaseClock};
 
 use crate::dsp::MAX_BLOCK_SIZE;
 

src/dsp/node_tslfo.rs

@@ -2,11 +2,11 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{TriSawLFO, Trigger};
 use crate::dsp::{
     DspNode, GraphAtomData, GraphFun, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom,
 };
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{TriSawLFO, Trigger};
 
 #[derive(Debug, Clone)]
 pub struct TsLFO {

src/dsp/node_vosc.rs

@@ -2,11 +2,11 @@
 // This file is a part of HexoDSP. Released under GPL-3.0-or-later.
 // See README.md and COPYING for details.
 
-use synfx_dsp::{Oversampling, apply_distortion, VPSOscillator};
 use crate::dsp::{
     DspNode, GraphAtomData, GraphFun, LedPhaseVals, NodeContext, NodeId, ProcBuf, SAtom,
 };
 use crate::nodes::{NodeAudioContext, NodeExecContext};
+use synfx_dsp::{apply_distortion, Oversampling, VPSOscillator};
 
 #[macro_export]
 macro_rules! fa_vosc_ovrsmpl {

src/lib.rs

@@ -321,8 +321,8 @@ pub mod monitor;
 pub mod nodes;
 pub mod sample_lib;
 pub mod scope_handle;
-pub mod wblockdsp;
 mod util;
+pub mod wblockdsp;
 
 pub use cell_dir::CellDir;
 pub use chain_builder::MatrixCellChain;

src/matrix.rs

@@ -8,9 +8,9 @@ use crate::matrix_repr::*;
 pub use crate::monitor::MON_SIG_CNT;
 pub use crate::nodes::MinMaxMonitorSamples;
 use crate::nodes::{NodeConfigurator, NodeGraphOrdering, NodeProg, MAX_ALLOCATED_NODES};
+use crate::wblockdsp::{BlkJITCompileError, BlockFun, BlockFunSnapshot};
 pub use crate::CellDir;
 use crate::ScopeHandle;
-use crate::wblockdsp::{BlockFun, BlockFunSnapshot, BlkJITCompileError};
 
 use std::collections::{HashMap, HashSet};
 

src/matrix_repr.rs

@@ -3,8 +3,8 @@
 // See README.md and COPYING for details.
 
 use crate::dsp::{NodeId, ParamId, SAtom};
-use serde_json::{json, Value};
 use crate::wblockdsp::BlockFunSnapshot;
+use serde_json::{json, Value};
 
 #[derive(Debug, Clone, Copy)]
 pub struct CellRepr {

src/nodes/node_conf.rs

@@ -6,15 +6,15 @@ use super::{
     FeedbackFilter, GraphMessage, NodeOp, NodeProg, MAX_ALLOCATED_NODES, MAX_AVAIL_CODE_ENGINES,
     MAX_AVAIL_TRACKERS, MAX_INPUTS, MAX_SCOPES, UNUSED_MONITOR_IDX,
 };
-use crate::wblockdsp::*;
 use crate::dsp::tracker::{PatternData, Tracker};
 use crate::dsp::{node_factory, Node, NodeId, NodeInfo, ParamId, SAtom};
 use crate::monitor::{new_monitor_processor, MinMaxMonitorSamples, Monitor, MON_SIG_CNT};
 use crate::nodes::drop_thread::DropThread;
-#[cfg(feature = "synfx-dsp-jit")]
-use synfx_dsp_jit::engine::CodeEngine;
+use crate::wblockdsp::*;
 use crate::SampleLibrary;
 use crate::ScopeHandle;
+#[cfg(feature = "synfx-dsp-jit")]
+use synfx_dsp_jit::engine::CodeEngine;
 
 use ringbuf::{Producer, RingBuffer};
 use std::collections::HashMap;

src/wblockdsp/compiler.rs

@@ -210,7 +210,7 @@ pub struct Block2JITCompiler {
 
 #[cfg(not(feature = "synfx-dsp-jit"))]
 pub enum ASTNode {
-    NoSynfxDSPJit
+    NoSynfxDSPJit,
 }
 
 impl Block2JITCompiler {

src/wblockdsp/definition.rs

@@ -208,39 +208,42 @@ pub fn setup_hxdsp_block_language(
         });
     }
 
-    dsp_lib.borrow().for_each(|node_type| -> Result<(), ()> {
-        let max_ports = node_type.input_count().max(node_type.output_count());
-        let is_stateful = node_type.is_stateful();
+    dsp_lib
+        .borrow()
+        .for_each(|node_type| -> Result<(), ()> {
+            let max_ports = node_type.input_count().max(node_type.output_count());
+            let is_stateful = node_type.is_stateful();
 
-        let mut inputs = vec![];
-        let mut outputs = vec![];
+            let mut inputs = vec![];
+            let mut outputs = vec![];
 
-        let mut i = 0;
-        while let Some(name) = node_type.input_names(i) {
-            inputs.push(Some(name[0..(name.len().min(2))].to_string()));
-            i += 1;
-        }
+            let mut i = 0;
+            while let Some(name) = node_type.input_names(i) {
+                inputs.push(Some(name[0..(name.len().min(2))].to_string()));
+                i += 1;
+            }
 
-        let mut i = 0;
-        while let Some(name) = node_type.output_names(i) {
-            outputs.push(Some(name[0..(name.len().min(2))].to_string()));
-            i += 1;
-        }
+            let mut i = 0;
+            while let Some(name) = node_type.output_names(i) {
+                outputs.push(Some(name[0..(name.len().min(2))].to_string()));
+                i += 1;
+            }
 
-        lang.define(BlockType {
-            category: if is_stateful { "nodes".to_string() } else { "functions".to_string() },
-            name: node_type.name().to_string(),
-            rows: max_ports,
-            area_count: 0,
-            user_input: BlockUserInput::None,
-            description: node_type.documentation().to_string(),
-            color: if is_stateful { 8 } else { 16 },
-            inputs,
-            outputs,
-        });
+            lang.define(BlockType {
+                category: if is_stateful { "nodes".to_string() } else { "functions".to_string() },
+                name: node_type.name().to_string(),
+                rows: max_ports,
+                area_count: 0,
+                user_input: BlockUserInput::None,
+                description: node_type.documentation().to_string(),
+                color: if is_stateful { 8 } else { 16 },
+                inputs,
+                outputs,
+            });
 
-        Ok(())
-    }).expect("seriously no error here");
+            Ok(())
+        })
+        .expect("seriously no error here");
 
     lang.define_identifier("in1");
     lang.define_identifier("in2");

src/wblockdsp/mod.rs

@@ -6,10 +6,10 @@
 
 */
 
+mod compiler;
 mod definition;
 mod language;
-mod compiler;
 
+pub use compiler::*;
 pub use definition::*;
 pub use language::*;
-pub use compiler::*;

tests/node_formant.rs

@@ -0,0 +1,133 @@
+mod common;
+use common::*;
+
+#[test]
+fn check_normalized_if_freq_lower_than_formant_freq() {
+    let (node_conf, mut node_exec) = new_node_engine();
+
+    let mut matrix = Matrix::new(node_conf, 3, 3);
+
+    let mut chain = MatrixCellChain::new(CellDir::B);
+    chain.node_out("formant", "sig").node_inp("out", "ch1").place(&mut matrix, 0, 0).unwrap();
+
+    matrix.sync().unwrap();
+
+    let formant = NodeId::Formant(0);
+
+    // params
+    let freq_p = formant.inp_param("freq").unwrap();
+    let form_p = formant.inp_param("form").unwrap();
+    let atk_p = formant.inp_param("atk").unwrap();
+    let dcy_p = formant.inp_param("dcy").unwrap();
+
+    // set params to reasonable values
+    matrix.set_param(freq_p, SAtom::param(-0.2));
+    matrix.set_param(form_p, SAtom::param(0.0));
+    matrix.set_param(atk_p, SAtom::param(0.2));
+    matrix.set_param(dcy_p, SAtom::param(-0.2));
+
+    // run
+    let res = run_for_ms(&mut node_exec, 100.0);
+
+    // and check it's normalized
+    let max = res.0.iter().fold(0.0 as f32, |acc, x| acc.max(*x));
+    let min = res.0.iter().fold(0.0 as f32, |acc, x| acc.min(*x));
+    assert!(max > 0.8 && max < 1.01 && min < -0.8 && min > -1.01);
+}
+
+#[test]
+fn check_no_dc_bias_at_formant_freq_lower_than_freq() {
+    let (node_conf, mut node_exec) = new_node_engine();
+
+    let mut matrix = Matrix::new(node_conf, 3, 3);
+
+    let mut chain = MatrixCellChain::new(CellDir::B);
+    chain.node_out("formant", "sig").node_inp("out", "ch1").place(&mut matrix, 0, 0).unwrap();
+
+    matrix.sync().unwrap();
+
+    let formant = NodeId::Formant(0);
+
+    // params
+    let freq_p = formant.inp_param("freq").unwrap();
+    let form_p = formant.inp_param("form").unwrap();
+    let atk_p = formant.inp_param("atk").unwrap();
+    let dcy_p = formant.inp_param("dcy").unwrap();
+
+    // set params to reasonable values
+    matrix.set_param(freq_p, SAtom::param(0.0));
+    matrix.set_param(form_p, SAtom::param(-0.2));
+    matrix.set_param(atk_p, SAtom::param(0.2));
+    matrix.set_param(dcy_p, SAtom::param(-0.2));
+
+    // run
+    let res = run_for_ms(&mut node_exec, 100.0);
+
+    // average should remain at ~0
+    let sum = res.0.iter().sum::<f32>();
+    let avg = sum / res.0.len() as f32;
+
+    assert!(avg > -0.05 && avg < 0.05);
+}
+
+#[test]
+fn check_no_nan() {
+    let (node_conf, mut node_exec) = new_node_engine();
+
+    let mut matrix = Matrix::new(node_conf, 3, 3);
+
+    let mut chain = MatrixCellChain::new(CellDir::B);
+    chain.node_out("formant", "sig").node_inp("out", "ch1").place(&mut matrix, 0, 0).unwrap();
+
+    matrix.sync().unwrap();
+
+    let formant = NodeId::Formant(0);
+
+    // params
+    let freq_p = formant.inp_param("freq").unwrap();
+    let form_p = formant.inp_param("form").unwrap();
+    let atk_p = formant.inp_param("atk").unwrap();
+    let dcy_p = formant.inp_param("dcy").unwrap();
+
+    // set params to non-reasonable values here
+    // base freq 0
+    matrix.set_param(freq_p, SAtom::param(-1.0));
+    matrix.set_param(form_p, SAtom::param(0.0));
+    matrix.set_param(atk_p, SAtom::param(0.2));
+    matrix.set_param(dcy_p, SAtom::param(-0.2));
+
+    // run
+    let res = run_for_ms(&mut node_exec, 100.0);
+
+    // and check there's no NaN
+    assert!(res.0.iter().all(|x| !x.is_nan()));
+
+    // set params to non-reasonable values here
+    // base freq attack freq 0
+    matrix.set_param(freq_p, SAtom::param(-0.2));
+    matrix.set_param(form_p, SAtom::param(0.0));
+    matrix.set_param(atk_p, SAtom::param(-1.0));
+    matrix.set_param(dcy_p, SAtom::param(-0.2));
+
+    // run
+    let res = run_for_ms(&mut node_exec, 100.0);
+
+    // and check there's no NaN
+    assert!(res.0.iter().all(|x| !x.is_nan()));
+
+    // set params to non-reasonable values here
+    // decay freq freq 0
+    matrix.set_param(freq_p, SAtom::param(-0.2));
+    matrix.set_param(form_p, SAtom::param(0.0));
+    matrix.set_param(atk_p, SAtom::param(0.2));
+    matrix.set_param(dcy_p, SAtom::param(-1.0));
+
+    // run
+    let res = run_for_ms(&mut node_exec, 100.0);
+
+    // and check there's no NaN
+    assert!(res.0.iter().all(|x| !x.is_nan()));
+}
+
+#[test]
+fn check_formant_freq() {}