ngpc: Sound emulation problems
Author: AidricEmblemCreated Sep 8, 2026Updated Sep 16, 2026
MAME version
0.289 (mame0289-731-gfa3f053e669)
System information
Windows 11 Home, 64-bit, version 25H2, USA, US English AMD Ryzen 7 8845HS x86-64, 16GB system RAM, GeForce RTX 4060 Laptop GPU driver version 32.0.16.9656 d3d video output
INI configuration details
#
# CORE CONFIGURATION OPTIONS
#
readconfig 1
writeconfig 0
#
# CORE SEARCH PATH OPTIONS
#
homepath .
rompath roms
hashpath hash
samplepath samples
artpath artwork
ctrlrpath ctrlr
inipath .;ini;ini/presets
fontpath .
cheatpath cheat
crosshairpath crosshair
pluginspath plugins
languagepath language
swpath software
#
# CORE OUTPUT DIRECTORY OPTIONS
#
cfg_directory cfg
nvram_directory nvram
input_directory inp
state_directory sta
snapshot_directory snap
diff_directory diff
comment_directory comments
share_directory share
#
# CORE STATE/PLAYBACK OPTIONS
#
state
autosave 0
rewind 0
rewind_capacity 100
playback
record
exit_after_playback 0
mngwrite
aviwrite
wavwrite
snapname %g/%i
snapsize auto
snapview auto
snapbilinear 1
statename %g
burnin 0
#
# CORE PERFORMANCE OPTIONS
#
autoframeskip 0
frameskip 0
seconds_to_run 0
throttle 1
sleep 1
speed 1.0
refreshspeed 0
lowlatency 0
#
# CORE RENDER OPTIONS
#
keepaspect 1
unevenstretch 1
unevenstretchx 0
unevenstretchy 0
autostretchxy 0
intoverscan 0
intscalex 0
intscaley 0
#
# CORE ROTATION OPTIONS
#
rotate 1
ror 0
rol 0
autoror 0
autorol 0
flipx 0
flipy 0
#
# CORE ARTWORK OPTIONS
#
artwork_crop 0
fallback_artwork
override_artwork
artwork_font default
#
# CORE SCREEN OPTIONS
#
brightness 1.0
contrast 1.0
gamma 1.0
pause_brightness 0.65
effect none
#
# CORE VECTOR OPTIONS
#
beam_width_min 1.0
beam_width_max 1.0
beam_dot_size 1.0
beam_intensity_weight 0
flicker 0
#
# CORE SOUND OPTIONS
#
samplerate 48000
samples 1
volume 0
#
# CORE INPUT OPTIONS
#
coin_lockout 1
ctrlr
mouse 0
joystick 1
lightgun 0
multikeyboard 0
multimouse 0
steadykey 0
ui_active 0
joystick_map auto
joystick_deadzone 0.15
joystick_saturation 0.85
joystick_threshold 0.3
natural 0
joystick_contradictory 0
coin_impulse 0
#
# CORE INPUT AUTOMATIC ENABLE OPTIONS
#
paddle_device keyboard
adstick_device keyboard
pedal_device keyboard
dial_device keyboard
trackball_device keyboard
lightgun_device keyboard
positional_device keyboard
mouse_device mouse
#
# CORE DEBUGGING OPTIONS
#
verbose 0
log 0
oslog 0
debug 0
update_in_pause 0
debugscript
debuglog 0
#
# CORE COMM OPTIONS
#
comm_localhost 0.0.0.0
comm_localport 15112
comm_remotehost 127.0.0.1
comm_remoteport 15112
comm_framesync 0
#
# CORE MISC OPTIONS
#
drc 1
drc_rwx 1
drc_use_c 0
drc_log_uml 0
drc_log_native 0
bios
cheat 1
skip_gameinfo 0
uifont default
ui cabinet
confirm_quit 0
ui_mouse 1
language
nvram_save 1
rtc
#
# SCRIPTING OPTIONS
#
autoboot_command
autoboot_delay 0
autoboot_script
console 0
plugins 1
plugin
noplugin
#
# HTTP SERVER OPTIONS
#
http 0
http_port 8080
http_root web
#
# OSD INPUT MAPPING OPTIONS
#
uimodekey auto
controller_map none
background_input 0
#
# OSD FONT OPTIONS
#
uifontprovider auto
#
# OSD OUTPUT OPTIONS
#
output auto
#
# OSD INPUT OPTIONS
#
keyboardprovider auto
mouseprovider auto
lightgunprovider auto
joystickprovider auto
#
# OSD DEBUGGING OPTIONS
#
debugger auto
debugger_host localhost
debugger_port 23946
debugger_font auto
debugger_font_size 0
watchdog 0
#
# OSD PERFORMANCE OPTIONS
#
numprocessors auto
bench 0
#
# OSD VIDEO OPTIONS
#
video d3d
numscreens 1
window 0
maximize 1
waitvsync 1
syncrefresh 0
monitorprovider auto
#
# OSD PER-WINDOW VIDEO OPTIONS
#
screen auto
aspect auto
resolution auto
view auto
screen0 auto
aspect0 auto
resolution0 auto
view0 auto
screen1 auto
aspect1 auto
resolution1 auto
view1 auto
screen2 auto
aspect2 auto
resolution2 auto
view2 auto
screen3 auto
aspect3 auto
resolution3 auto
view3 auto
#
# OSD FULL SCREEN OPTIONS
#
switchres 0
#
# OSD ACCELERATED VIDEO OPTIONS
#
filter 0
prescale 1
#
# OpenGL-SPECIFIC OPTIONS
#
gl_forcepow2texture 0
gl_notexturerect 0
gl_vbo 1
gl_pbo 1
gl_glsl 0
gl_glsl_filter 1
glsl_shader_mame0 none
glsl_shader_mame1 none
glsl_shader_mame2 none
glsl_shader_mame3 none
glsl_shader_mame4 none
glsl_shader_mame5 none
glsl_shader_mame6 none
glsl_shader_mame7 none
glsl_shader_mame8 none
glsl_shader_mame9 none
glsl_shader_screen0 none
glsl_shader_screen1 none
glsl_shader_screen2 none
glsl_shader_screen3 none
glsl_shader_screen4 none
glsl_shader_screen5 none
glsl_shader_screen6 none
glsl_shader_screen7 none
glsl_shader_screen8 none
glsl_shader_screen9 none
#
# OSD SOUND OPTIONS
#
sound auto
audio_latency 0.0
#
# OSD MIDI OPTIONS
#
midiprovider auto
#
# OSD EMULATED NETWORKING OPTIONS
#
networkprovider auto
#
# BGFX POST-PROCESSING OPTIONS
#
bgfx_path bgfx
bgfx_backend auto
bgfx_debug 0
bgfx_vectorcrt 1
bgfx_screen_chains
bgfx_shadow_mask slot-mask.png
bgfx_lut lut-default.png
bgfx_avi_name auto
#
# WINDOWS PERFORMANCE OPTIONS
#
priority 0
profile 0
#
# WINDOWS VIDEO OPTIONS
#
attach_window
#
# DIRECT3D POST-PROCESSING OPTIONS
#
hlslpath hlsl
hlsl_enable 0
hlsl_oversampling 0
hlsl_write auto
hlsl_snap_width 2048
hlsl_snap_height 1536
shadow_mask_tile_mode 0
shadow_mask_alpha 0.0
shadow_mask_texture shadow-mask.png
shadow_mask_x_count 6
shadow_mask_y_count 4
shadow_mask_usize 0.1875
shadow_mask_vsize 0.25
shadow_mask_uoffset 0.0
shadow_mask_voffset 0.0
distortion 0.0
cubic_distortion 0.0
distort_corner 0.0
round_corner 0.0
smooth_border 0.0
reflection 0.0
vignetting 0.0
scanline_alpha 0.0
scanline_size 1.0
scanline_height 1.0
scanline_variation 1.0
scanline_bright_scale 1.0
scanline_bright_offset 0.0
scanline_jitter 0.0
hum_bar_alpha 0.0
defocus 0.0,0.0
converge_x 0.0,0.0,0.0
converge_y 0.0,0.0,0.0
radial_converge_x 0.0,0.0,0.0
radial_converge_y 0.0,0.0,0.0
red_ratio 1.0,0.0,0.0
grn_ratio 0.0,1.0,0.0
blu_ratio 0.0,0.0,1.0
saturation 1.0
offset 0.0,0.0,0.0
scale 1.0,1.0,1.0
power 1.0,1.0,1.0
floor 0.0,0.0,0.0
phosphor_life 0.0,0.0,0.0
chroma_mode 3
chroma_conversion_gain 0.299,0.587,0.114
chroma_a 0.64,0.33
chroma_b 0.30,0.60
chroma_c 0.15,0.06
chroma_y_gain 0.2126,0.7152,0.0722
#
# NTSC POST-PROCESSING OPTIONS
#
yiq_enable 0
yiq_jitter 0.0
yiq_cc 3.57954545
yiq_a 0.5
yiq_b 0.5
yiq_o 0.0
yiq_p 1.0
yiq_n 1.0
yiq_y 6.0
yiq_i 1.2
yiq_q 0.6
yiq_scan_time 52.6
yiq_phase_count 2
#
# VECTOR POST-PROCESSING OPTIONS
#
vector_beam_smooth 0.0
vector_length_scale 0.5
vector_length_ratio 0.5
#
# BLOOM POST-PROCESSING OPTIONS
#
bloom_blend_mode 0
bloom_scale 0.0
bloom_overdrive 1.0,1.0,1.0
bloom_lvl0_weight 1.0
bloom_lvl1_weight 0.64
bloom_lvl2_weight 0.32
bloom_lvl3_weight 0.16
bloom_lvl4_weight 0.08
bloom_lvl5_weight 0.06
bloom_lvl6_weight 0.04
bloom_lvl7_weight 0.02
bloom_lvl8_weight 0.01
lut_texture lut-default.png
lut_enable 0
ui_lut_texture lut-default.png
ui_lut_enable 0
#
# FULL SCREEN OPTIONS
#
triplebuffer 0
full_screen_brightness 1.0
full_screen_contrast 1.0
full_screen_gamma 1.0
#
# INPUT DEVICE OPTIONS
#
dual_lightgun 0Emulated system/software
NeoGeo Pocket Color (ngpc), Metal Slug - 2nd Mission (World) (ngpc:mslug2nd), Sonic the Hedgehog - Pocket Adventure (World) (ngpc:sonic)
Incorrect behaviour
Some parts of the music are missing, which is noticeable in the Neo Geo Pocket BIOS and Sonic the Hedgehog - Pocket Adventure. Metal Slug - 2nd Mission loses all T6W28 sound after samples play from the DAC.
Metal Slug 2nd Mission (MAME).mp3 Metal Slug 2nd Mission (Mednafen).mp3 NGPC BIOS (Ares).mp3 NGPC BIOS (MAME).mp3 Sonic the Hedgehog Pocket Adventure (MAME).mp3 Sonic the Hedgehog Pocket Adventure (Mednafen).mp3
Expected behaviour
Music and sound should play similarly to:
- original hardware
- Ares
- Mednafen None of which exhibit these issues.
Steps to reproduce
Run the NeoGeo Pocket Color system; the sound issues are immediately audible. Running Metal Slug - 2nd Mission or Sonic the Hedgehog - Pocket Adventure will also demonstrate immediately audible sound emulation issues.
Additional details
No response
Source: mamedev/mame