initialize all voices instead of dynamic allocation (fixes access errors)

synth/midi_synth.h

@@ -14,12 +14,10 @@ namespace trnr {
 template <typename t_voice, typename t_sample>
 class midi_synth : public voice_allocator<t_voice, t_sample> {
 public:
-	midi_synth(size_t voice_reserve = 1)
+	midi_synth(size_t num_voices = 1)
 		: m_voices_active {false}
+		, trnr::voice_allocator<t_voice, t_sample>(num_voices)
 	{
-		// call base constructor with a reserve of 1 voice
-		voice_allocator<t_voice, t_sample>::set_voice_count(voice_reserve);
-
 		// checks whether template derives from ivoice
 		typedef t_voice assert_at_compile_time[is_convertible<t_voice, t_sample>::value ? 1 : -1];
 	}