function P = bass_defaults()
% BASS_DEFAULTS Default parameters, mirroring the web app's params.ts.
% The output duration is not a parameter: it is
% (note_count - 1) * 60 / tempo_bpm + tail_s.

% Strings (1 = G2, 2 = D2, 3 = A1, 4 = E1), a 3/4-size double bass.
% Linear density is not a parameter: it follows from the tension and the
% open pitch, mu = T / (2 L f0)^2, which lands on realistic values
% (about 7 g/m for the G string, 42 g/m for the E).
P.scale_length_m = 1.04;
P.tension_g_n = 285.0;
P.tension_d_n = 290.0;
P.tension_a_n = 300.0;
P.tension_e_n = 310.0;
P.inharmonicity = 8.0e-5;  % B of the open string: f_n ~ n f0 sqrt(1 + B n^2)
P.tuning_trim = 1.0;       % overall pitch trim (1 = standard orchestral tuning)

% String damping
P.loss_factor = 1.6e-3;    % frequency-independent internal loss
P.loss_slope = 4.0e-7;     % extra high-frequency loss, s
P.finger_loss = 6.0e-3;    % extra loss factor on stopped notes (finger termination)
P.residual_y = 0.015;      % residual bridge conductance above the retained body modes, s/kg

% Body (see bass_body.m for the mode table these trims act on)
P.a0_hz = 58.5;            % f-hole Helmholtz resonance
P.body_trim = 1.0;         % scales the corpus mode frequencies
P.body_q_scale = 1.2;      % scales the body mode Qs
P.bridge_mobility = 1.0;   % scales the body admittance seen at the bridge (1/masses)
P.rad_area_scale = 1.0;    % scales the radiating areas of the body modes
P.dipole_length_m = 0.45;  % effective front-to-back path of the corpus dipoles
P.radiation_loss = 1.0;    % scales the radiation damping added to the body Qs

% Pluck
P.pluck_force_n = 15.0;    % transverse pull at release
P.pluck_pos = 0.38;        % fraction of the vibrating length, measured from the bridge
P.finger_release_ms = 2.6; % finite release time of the fingertip (spectral rolloff)
P.choke_ms = 45.0;         % decay time constant applied when the next note lands

% Gesture
P.root_midi = 33;          % A1; the single note, and the key of a walking line
P.note_count = 1;
P.tempo_bpm = 96.0;
P.force_spread = 0.20;     % lognormal spread of the pluck force across a line
P.timing_jitter_ms = 4.0;
P.seed = 1;

% Radiation / listener (origin at the bridge, +y up the neck, +z out of the top plate)
P.direct_gain = 0.7;
P.listener_x_m = 0.50;
P.listener_y_m = 0.30;
P.listener_z_m = 1.20;
P.speed_of_sound = 343.0;
P.air_density = 1.204;

% Rendering / output
P.max_mode_hz = 3000.0;
P.sample_rate = 48000;
P.oversample = 2;
P.tail_s = 8.0;
P.pre_delay_ms = 3.0;
P.normalize = 1;
P.peak_dbfs = -3.0;
P.full_scale_pa = 2.0;
end