Why is the sound quality recorded with FMPPZ poor?

[denjhang]

Using np21 vgm mod to record ppz (psg pcm driver z) driven by fmp has poor sound quality, and the same is true for pps driven by pmd. But directly using fmpmd2000 to play, or using a real machine, the effect will be much better.
Is there a better way?

[ValleyBell]

I know that NP21 itself has a few issues regarding PSG PCM.
It has some DC offset removal code in its PSG emulation that doesn't play nice with PMD-PPS and causes heavy distortion. However, the VGM logs are unaffected by this.

If you plan to record songs that use PSG PCM, please as in the chat first though. The PMD PPS driver does some optimization that makes it impossible to use PCM optimization tools on it.
Some time ago I made a patched PPS driver that removes the optimization and thus allows for PCM optimization as a post-processing step. (Removing the optimization also happens to reduce the distortion in NP21.)

[denjhang]

Where is the patch, please link me.

I know that NP21 itself has a few issues regarding PSG PCM.
It has some DC offset removal code in its PSG emulation that doesn't play nice with PMD-PPS and causes heavy distortion. However, the VGM logs are unaffected by this.

If you plan to record songs that use PSG PCM, please as in the chat first though. The PMD PPS driver does some optimization that makes it impossible to use PCM optimization tools on it.
Some time ago I made a patched PPS driver that removes the optimization and thus allows for PCM optimization as a post-processing step. (Removing the optimization also happens to reduce the distortion in NP21.)

[denjhang]

Recently I have devoted myself to recording and improving YM2608 VGM. When will ValleyBell release the patch?
If possible, thank him very much. I will also record and upload more VGM packages to vgmrips.