MAKING A POINT

摘要

I'd like to respond regarding Keith Howard's reply to a question regarding digitally applied RIAA equalization [HFN Sept '07]. First, my company (Pure Vinyl) offers real-time software that does indeed use double-precision floating point maths throughout the entire signal processing chain. Mr Howard seems to imply that this cannot be done in real-time. Second, regarding the phase response of the RIAA filtering, it can be anything (within reason) that the filter designer wants it to be: zero phase shift or otherwise. Actually, we have chosen a phase profile that is essentially identical to that of the analogue filtering network used in a conventional phono preamp.