System/Library/PrivateFrameworks/SiriSpeechSynthesis.framework

QSSMutablePronunciation.h

NSObject
>
QSSPronunciation

@class NSString;

@interface QSSMutablePronunciation : QSSPronunciation

@property (copy, nonatomic) NSString *phonemes;

- (id)init;
- (id)copyWithZone:(struct _NSZone { } *)a0;

@end