Rendering with PDC sometimes cuts beginning of initial sounds

Steps to reproduce:

1 Add a plugin/effect that introduces PDC, for example mastering plugin. Check PDC report.

  1. Now render song, setting doesn’t matter.

  2. Re-render, this time with melda mrecorder.

  3. Compare the beginning of both files in a sample editor. Renoise renders lost some beginning transients…

Expected result:

The rendering should start at the correct position, not cutting any beginning transient. Just like played live.

Which plugin have you tested this with? This will very likely change with every plugin, depending on what exactly the plugin does to delay the sound.

If a plugin reports latency, this does not necessary mean that it always adds X amount of !silent! samples to the buffer. When for example using filters which introduce latency, the transients will roughly be delayed by a given amount while the “surrounding” samples are not exactly silent.

As host, we can only compensate what gets reported by plugins. If some transients are really missing, then maybe the reported latency is simply a bit too high in this case?

oh ok, it tested that new lurssen master plugin by ik multimedia. seems to be buggy then.

Taktik, I have another concern regarding that lurssen plugin:

If I render the song in live rendering mode, it will sound DIFFERENT to live played. I made a phase inversion test live (thru melda mrecorder) vs live rendering:

The diff is actually noise, and some little bass.

If I compare now mrecorder vs offline hq rendering, the noise is gone in the diff!

So, how it is possible that a plugin can act differently on live rendering vs. live playing? Shouldn’t it behave exactly the same?

Any idea?

So, how it is possible that a plugin can act differently on live rendering vs. live playing? Shouldn’t it behave exactly the same?

The plugin gets notified by the host when it’s being offline rendered, instead of real-time played. Some plugins automatically use different (HQ) rendering modes then. I never tried the lurssen master, but if the plugin does so, there usually is an option for this in the plugin to enable/disable that.

no no, it sounds different on live rendering mode, it sounds the same on offline-rendering mode.

Is there a notification to the plugins on live rendering mode, too?

Hi Taktik,

I think the important point here is, that actually a plugin CAN SOUND DIFFERENT IN LIVE RENDERING VS. LIVE PLAYING, as stated in post #3 (both recorded in 32bit float).

So can you please do another deep thinking about how to prevent plugins 100%from detecting a rendering for live rendering mode?

As you can see, the lurssen mastering thing sounds different live played vs. live rendering.

So is the timing or whatever some how different in rendering mode? Is it maybe because of different inter-sample interpolation? Or different dithering?