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View Full Version : DJ Mix CD's ripped to mp3 - what's the gap like in playback?



charlesr
2006-01-10, 10:46
Hi
I'm thinking of getting a squeezebox3 and have a question about the gap between tracks during playback.

When I rip a DJ Mixed dance CD to mp3 and play it back, on some playback devices there is a noticeable gap between tracks which is quite annoying and on others it is barely noticeable.

For example, Window Media Player is almost seamless between the mp3 tracks, so the DJ's work isn't messed up. Similarly on my in car cdmp3 player. On my friend's Roku Soundbridge it's also very good. But on my Benq portable mp3 player, there is a noticeable pause while it loads up and starts playing the next track (perhaps 1/3rd of a second).

What's the gap between tracks like on the squeezebox3?

When I've asked this question about other devices before, i've had responses talking about removing gaps between gaps while ripping, so just to be clear - there are no gaps between tracks -it's a seamless DJ mix and the length of the audible gap during playback of the ripped mp3s is a function of the media player/device, not the ripping software.

Many thanks!
Charlesr

radish
2006-01-10, 11:33
When I've asked this question about other devices before, i've had responses talking about removing gaps between gaps while ripping, so just to be clear - there are no gaps between tracks -it's a seamless DJ mix and the length of the audible gap during playback of the ripped mp3s is a function of the media player/device, not the ripping software.


No, the gap is primarily a function of the format. MP3 (well, standard MP3 anyway*) cannot do proper gapless playback. If you want gapless, use a gapless format like WAV, FLAC or Vorbis. Squeezebox will play all those back gapless just fine.

(*) There are hacks to make MP3 gapless. One approach is for the player to try and guess the true length of the track by looking for silence, this is error prone. Another is for the encoder (LAME is the only one to support this IIRC) to write special comments with the correct file length in. This requires player support as well, I think there's an open request for this to be added to Squeezebox. Regardless, if you didn't rip it in the correct version of LAME in the first place that won't help you. Finally, LAME will also allow you to rip and entire album gaplessly by moving the track start/end points to fit into exact frames. If you do it that way then it should be gapless on most players, Squeezebox included (but I haven't tested it).

charlesr
2006-01-10, 17:23
Thanks - useful stuff.

Ok, so let's say I'm completely happy with the tiny almost imperceptable gap between my mp3 tracks that windows media player and the Roku soundbridge do, and there's no way I'd consider re-ripping my 400+ albums again any time soon, will I be happy with the gap between tracks on the Squeezebox? Will it be similarly small? That is all I need to know before slapping my credit card down. I intend to convert it all to FLAC at a later date when I have replacement HDs with enough space, so later it's not going to be a problem.

ajmitchell
2006-01-12, 15:51
If I understand your question correctly, there need be no gap at all...in fact squeezebox allows a seamless crossfade from 1-10 seconds when there is a period when both current and next track plays simulatanously. The only bug in the ointment (literally!) is that this feature will not currently work when multiple squeezeboxes are synched together...although a fix is promised.

charlesr
2006-01-12, 16:38
Cross fade would screw up the DJ mix (the DJ does the cross fading on dance CDs in the studio during recording!).
Is anyone able to tell me how big the gap would be without crossfade on my amateurly encoded mp3s? :D

radish
2006-01-12, 17:06
Cross fade would screw up the DJ mix (the DJ does the cross fading on dance CDs in the studio during recording!).
Is anyone able to tell me how big the gap would be without crossfade on my amateurly encoded mp3s? :D

You're right - crossfade is the last thing you want!

I just loaded up one of my own mixes (which I keep in a number of formats for ease of distribution to potential clients) and took a listen on my SB2. The gap is pretty tiny, the SB prebuffers so there's no transmission delay, just the frame space at the end. No pop or anything, just a momentary silence. Enough to annoy me (I'm a perfectionist!) but I'm sure fine for most people.

charlesr
2006-01-13, 00:47
Sold! You star! Thanks to everyone who took the time to read this thread. I'll probably be back with some "I've just bought one and can't do this and that" type questions soon :D

francis_lhert
2006-04-11, 01:32
You're right - crossfade is the last thing you want!

I just loaded up one of my own mixes (which I keep in a number of formats for ease of distribution to potential clients) and took a listen on my SB2. The gap is pretty tiny, the SB prebuffers so there's no transmission delay, just the frame space at the end. No pop or anything, just a momentary silence. Enough to annoy me (I'm a perfectionist!) but I'm sure fine for most people.

How to remove or reduce these silences ?
Somewhere on the technical documentation I have seen there are "silent frames" added at the beginning of files.

radish
2006-04-11, 06:47
How to remove or reduce these silences ?
Somewhere on the technical documentation I have seen there are "silent frames" added at the beginning of files.

Take a look at my first response on this thread. The best advice is to not use mp3 if you want gapless.

autopilot
2006-04-11, 10:46
Hello mate.

I asked the exact same question before i wanted to buy an SB3, as 1/3 of my CD collection requires gapless playback. I can tell you that you wont be disapointed. But i would HIGHLY recommend you use a different format, as people here have already said. Use either FLAC or Vorbis, which are designed for gapless.


I intend to convert it all to FLAC at a later date when I have replacement HDs with enough space, so later it's not going to be a problem.

Do you mean you intend to convert all your MP3's to FLAC? Don't bother - a) you wont get any improvement in sound quality, what was lost when comressing to MP3 is lost forever. b) The gap is actually in the MP3 files (padding frames added by the encoder) and converting to FLAC wont solve the problem. Re-rip your CD's to FLAC or Vorbis.

One other option in to rip to one long file and use a CUE sheet for track names and times (tracks still appear as single tracks in slimserver because it reads the cue sheet). This is the best way to get true faultless gapless playback (works with MP3 too).

charlesr
2006-04-11, 12:06
Thanks, I did mean rerip it all from CD to FLAC :)

qirex
2006-04-17, 08:50
Has anyone checked for gaps using Apple Lossless? Out of sheer habit I've ripped my mixtapes as a single track.

autopilot
2006-04-17, 10:20
Has anyone checked for gaps using Apple Lossless?

As far as i know, it does not explicitly support gapless in the way Vorbis and FLAC do. But then Apple have nothing to gain from it being gapless as the iPod does not support gapless playback.

EDIT : Here is a usful link - http://www.pretentiousname.com/mp3players

hifisteve
2006-04-18, 06:53
I use Apple Lossless for all of my music and have quite a number of mixed CDs.

My experience is that the 'gap' is almost imperceptable, that is to say that if you are really listening for it you will hear it but otherwise it's fine. It's more of a slight skip than a gap as such.

charlesr
2006-04-18, 15:10
Well, I've finally gotten around to testing out FLAC. I used EAC to rip to wav and to convert that to FLAC. I unchecked "add id3 tag" to avoid any unecessary info being added.

My current setup is a laptop (plugged into the amp/speakers), streaming wirelessly off the PC. First I tried winamp (just streaming all tracks in a folder - i.e. not using slimserver) and it's TOTALLY seamless (once I'd set the "buffer ahead on track change" to 2000. Zero gap. Most excellent.

I don't have a squeezebox (yet!), so I'm trying softsqueeze (NOT the applet version - the install version) on my laptop, so I tried that next, but I get a quite large gap. The only setting I could find of relevance on slimserver is "Build Items Per Pass -
To avoid interrupting the music, SlimServer builds long lists in chunks. This setting determines how many items to build in a single pass" - this is currently set to 20. Not quite sure if this is relevant but I tried raising it to 100 anyway, but still no change - softsqueeze still giving a gap. I tried softsqueeze on the server/PC as well but with the same gap. So my question is.... does the squeezebox3 have something that softsqueeze doesn't? Some extra buffering? Or will the squeezebox3 give the same gap? Sorry to keep coming back to this - but as each step seems to bring me a little closer, something else crops up to put a dampener on things :)

autopilot
2006-04-19, 11:15
Try not to compare Softsqueeze with a proper SB3. It's not a true emulator and there are lots of differences. You wont have a gap, it will be as good as, probably better than, Winamp :)

charlesr
2006-04-19, 14:31
That's the answer I was looking for. So where's the best place to buy one in the UK, or should I import from slimserver?

autopilot
2006-04-20, 12:34
You won't save any money importing, i looked into this a lot a few months ago. After import charges etc etc it worked out slightly more expensive. Also, if it goes faulty it could take ages to get it to the US and back and probably have to pay the shipping.

Buy it from www.scan.co.uk. Trust me, they are the best online retailer in the UK by a country mile. I have bought a lot stuff from them over the years, thier award winning customer service is absolutly the best i have ever come across. I can't recommend them more mate. And no, i dont work for them!

charlesr
2006-04-20, 23:54
Thanks. I've used Scan many times. However, this time I've placed an order with these guys: http://www.multitask-computing.co.uk/catalog/
209 with free DHL delivery. They do qnap NAS too, which I'm quite interested in once HD prices come down a bit (so 6 months time probably!)
I'll let you know what the service is like there.
Many thanks to everyone for you knowledgeable advice.

charlesr
2006-04-26, 03:00
My squeezebox3 just arrived and I can confirm even with mp3s that haven't been messed about with (just ripped using Nero) the gap is negligable - smallest gap I've heard on any player. :D

Awesome. Most impreseed. Many thanks all.

davidcotton
2006-04-26, 03:05
Copied across a couple of albums ripped in flac last night. No gaps whatsoever. There was narration linking the tracks so would have been noticeable.