Pregap problem help please


I just burned a cd for the first time from an audio montage, and played it in my car stereo.

The problem is that even though I left approximately 200 ms as pregap, the very beginning of the songs get chopped off. I thought 200 ms was more than enough to have as pregap? A friend of mine said he use to have 100 ms.
Is this problem occurring because I use splice markers? There is no “negative time” before each song?
Any suggestions what I should do?

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First grab your audio contents in WaveLab from the CD, to verify that the data is complete as expected.

How is the behavior with other CDs professionally mastered? My car CD player (2017 VW) seems to do a brief fade up when skipping to tracks no matter what.

For fun I should make a CD that has 1 full second between the track start marker and the first beat of a song and see if the CD player is muting silence (like a gate) or if it’s slow to unmute after skipping to a certain track.

Excuse me, I dont understand really what you mean?

Extract the audio files from your CD, to verify that the songs are fully written.

I have never played a cd in the car, I only listen to spotify nowadays :smiley:
But maybe 1 second pregap isn’t so bad? At least one is safe then?

I think we are starting to confuse terms. Pre-gap is the space between the CD Track End Marker and the next CD Track Start Marker. The main issue you’re having here is the gap between the start marker and the start of the audio. Whether it’s a CD Track Splice marker or a traditional end/start marker with space between them, you’ll likely see the same issue.

I personally think 1 second between the start marker and the first audio is too much. I would test a few other CDs behavior in your specific CD player before you start making decisions like this. Also, test the CD in a few other CD players if you have that option.

As PG says, load the CD (or DDP of the montage) back into WaveLab and see what’s really there.

First, arrange the clips to you or your clients liking on the timeline so they sound right when played back to back. Then just make sure the CD Track Splice marker is roughly 150 to 300ms before any audio of the next track and this should be OK. Adding 1 second of space between the CD Track Start marker and the first beat will be too much space in my opinion, especially on the streaming services.

Also, one thing that is really helpful if you don’t already have one is a DDP Player. I am in the habit of making a DDP of everything first to print all the audio processing, CD-Text, Markers etc, and then burn the DDP to CD when a CD is needed.

Using a DDP Player from HOFA or Sonoris can give you a good idea how it feels when skipping from track to track, as well as what the CD-Text looks like. You can do this in WaveLab of course but I think the HOFA DDP Player gives a more consumer view of what’s what.

I no longer burn a CD direct from montages with plugin processing because I think it’s good to quality control the plugin processing and other technical details before burning a CD of it.

I saw the same thing in a friend’s VW. I consider it a mistake on VW’s part to give no options, and simply have to disregard that player because it’s totally non-standard and is noticeable on at least one or two tracks on most standard gap commercial cd’s.

I saw a similar but somewhat different thing in a very inexpensive boombox from Best Buy. It would autoplay (no option) when you inserted a cd and on the first track would always fade up about 2 secs (but only on the first track), ramping into every cd I attempted to play, so unfortunately it’s heavily dependent on some badly programmed cd players with no options IMO, that are going to be “wrong” with pretty much every cd out there.

There are standard CD marker offset options in the CD Wizard (“adjust gaps between markers and sound”) that pretty much conform to other mastering programs like Soundblade, for automatic offset of the CD track markers from pre-trimmed clips (although the default offsets are 330ms standard, or 200ms for splices, in Soundblade I think). It creates the CD markers offset from the clips by the number of frames specified. With the defaults, it gives about the same offsets that Justin is suggesting I think (“silence after track start marker” = 15 CD frames = 200ms).

Mr. Picker, like Justin said, try some commercial CDs in the the car player and see if you don’t get the same thing, at least on some tracks where it’s obvious with hard starts. If so I would blame the car player. The offset “standards” have been around in mastering programs for a long time.

Also MrPicker, when you say 200 ms pregap, you do mean 200 ms silence/space between the splice marker and the incoming audio don’t you? That would be a normal safety offset. But if you mean the 200 ms silence is before the splice marker as “pregap”, and the splice marker is placed right on incoming audio, that’s not going to work well. You need the little safety zone (the 200-300 ms) between the splice marker and the start of audio.

Sorry I wasn’t sure if that’s what you meant when you said pregap.

And no, there is no “negative time” countdown with splice markers.

Hey, thanks for all your advices.

I imported the cd into wavelab and choosed " convert all tracks to audio montage". Like you se in pic 1: “cdaudiomontage”.

And when I zoom in at the beginning of the tracks it looks like this: See pic 2 “audiomontagezoomed”.

As you see there is 200 ms of silence before the track, as I intented when I burned the cd, so nothing seems to have gone wrong there?

I listened to some other “professional” cds, and one cd seemed to work fine, and the other seems to have the same problem as mine on some songs. I imported the cd that seemed to be fine into wavelab, and if I read it right, that master engineer have left aroud 230 ms before the songs. But that seems strange because I cant imagne that it would be different if I add 30 ms to my songs beginnings? :S

What do you think?

One more question. When I imported that professional cd into wavelab, wavelab automatically made splice markers, like it did on my cd (since I used it I guess). But does this mean that the guy that mastered that cd also had no time “between” the songs? (like it would be if I used only start and end markers instead of splice markers).

What you show on the zoomed in version looks reasonable to me. Did you test in another CD player? Did you try in a DDP Player?

I’ve never tested how WaveLab imports CDs with gaps between the markers (negative time). Maybe you can burn one and import to test if it brings back the markers exactly as they were or if it makes CD Track Splice Markers.

PG may also be able to just tell you here.

I don’t own a DDP player, i don’t even know what it is :S. But I just did test it in our other car, and there it worked fine, no chopped beginnings! I am thinking about increase the silence before the tracks to 300 ms and see if the problem still occurs!

DDP is a great way to transmit masters for CD production to the CD manufacturer. Most accept DDP and it’s generally faster and more reliable than delivering a CD-R master which is more prone to errors and issues. I also love DDP for getting project approvals from clients. I render the DDP from WaveLab montage, use HOFA DDP Player Maker to generate a software DDP Player that the client can use to open the master and do nothing but listen to it. They can’t edit it. They can examine the audio, track markers, CD-Text and all that via their computer and then burn a CD-R direct from the DDP Player if they want to.

HOFA DDP Player:

HOFA DDP Player Maker:

Even without all that, it’s not a bad idea to render your montage to DDP to print all the sounds, plugins, track IDs etc, and then burn a CD from WaveLab via the DDP. It’s a good place to check everything one last time before you burn the CD. WaveLab can export and import DDP no problem.

Regarding the man issue, I think you’ll find that each CD player is a little different and it’s up to you how much you want to cater to all CD players which could be an impossible task.

Wavelab can only detect gaps during CD import if you’re using an old Plextor CD drive to read the CD. Any modern drives will result in splice markers (no gap) being generated by Wavelab, whether the original mastered CD used Splice markers or standard CD track Start and End markers with gap.

Exact Audio Copy is a free program on Windows that can accurately detect gaps and markers (including CD Index markers) using virtually any CD drive (using the “detect gaps” function), so it can tell if the original mastered CD had gaps and used CD Splice or Start and End markers. If EAC indicates a gap time > 0, they used standard CD Track Start and End markers with gap there. You can make an cue image file from the CD read in EAC to open in Wavelab to see the markers.

Not sure if any programs on Mac can do that. Maybe Hofa or Sonoris if they can read CDs (not sure if any of their products can).

It looks like XLD on Mac can detect the gap markers, and extract a cue image that can then be imported into Wavelab. XLD doesn’t seem to read “in-track” sub-index markers like EAC does (Index 2,3,4…), but that’s not needed for gap checking anyway. But they might have a newer version that does.