Voice Manipulator 2 is very good soft for sample sound.
I test it on clone БЭМЗ "Байт" and work everything except LOAD/SAVE operations. While try write or load sample data the computer resets. Probably it comes to other I/O ports. Please help in debugging and improving the code.
To test please use ZXMAK2 or any emulator with "Byte" ROM - byte_roms.zip
Карта портов компьютера "Байт"