Audio pop when CD track begins playing

softtest9
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Audio pop when CD track begins playing

Unread post by softtest9 »

I am guessing that this has to do with audio being streamed from the Linux side. Perhaps a solution would be to keep the Linux audio muted while it's being initialized. If this results in audio being cut off, then perhaps audio could be initialized when the core boots instead, and keep it active all the time (but muted when it's not used)?
dshadoff
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Re: Audio pop when CD track begins playing

Unread post by dshadoff »

Can you give a specific example ?

I haven't seen anything of this sort on any any rips made properly. However, I have seen a few video captures of things like this, and the reason was because the disc image of the game being played was bad.

In these cases, either:
a) The track itself isn't ripped properly (sound at either end of the audio track coming from the start/end of a neighbouring track), or
b) The reconstruction of the tracks into a complete disc (i.e. CUE sheet) had improper timings
(or both)

-> Many games request audio playback based on time signature, so if the audio on your rip isn't precisely the same timing as the original disc, it can play incorrectly.

There is one further individual case, which is the shooting game Sapphire - the original disc was mastered as "track at once", rather than "disc at once", so audio rips may end up having some linkage data at either end (sounds like noise) if the ripping tool wasn't able to deal with this.
softtest9
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Re: Audio pop when CD track begins playing

Unread post by softtest9 »

I notice the audio pop the most in Spriggan Mark 2: Re Terraform Project (Japan). It tends to happen in the beginning or end of cutscenes or voice dialogues. It's especially noticeable right after the first voice dialogue in the second stage.

My PC Engine CD images are from the Redump set. Just to make sure that nothing went wrong with the image, I went to Redump's website and compared the MD5 hashes of all the bin files for the game. I couldn't spot anything wrong with the bin files' hashes. The cue file's contents appear to be identical as well.
LeftEmpty
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Re: Audio pop when CD track begins playing

Unread post by LeftEmpty »

Oh that's not the CD, that's the PCM playback of the PC Engine. It is quite common on the real machine, and especially noticeable if you play through an equalizer amplifying bass or with headphones.
dshadoff
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Re: Audio pop when CD track begins playing

Unread post by dshadoff »

softtest9 wrote: Sun May 31, 2020 7:37 pm My PC Engine CD images are from the Redump set. Just to make sure that nothing went wrong with the image, I went to Redump's website and compared the MD5 hashes of all the bin files for the game. I couldn't spot anything wrong with the bin files' hashes. The cue file's contents appear to be identical as well.
I make no assumptions about downloads whatsoever, no matter the origin. I have ripped my own discs, so I can validate on my rips and/or real hardware if needed. But specifics are always required.

In this case, it looks like somebody else has already responded.
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