Scoobateers,

Any one own an MP3 based head unit? I personally own an Alpine 7893R which I am very impressed with. However there are some niggles which I'm not sure are unit related or just down to the limitations of the MP3 technology.

> MP3 files encoded using joint stereo can sound jittery on playback especially if they have rapid beats (techno etc). I have to stick with standard Stereo which lowers the compression ratio.
> Theres is an annoying pause in between tracks as it reads the next file. This can be extremely frustrating if you are playing some kind of seamless mix. The only way to have seamless playback is to encode all tracks as one but you can't forward to the next track only fast forward.
> It takes ages to FF through tracks!


As I say, my unit is first generation so maybe these niggles will be ironed out of forthcoming releases.


Comments appreciated.

I've got the KDC-PSW9524 and have none of these troubles - have a google to see if it's a commonly known problem that you can fix with different encoding parameters...

I've just bought the Alpine 9812RB - I'll play tonight and let you know - I've not noticed anything up to now..

:cool:

This is down to your MP3 / CD burning package
If u use Nero 6 for example there is an option to switch of the default 2 secs pause between tracks. Also if your files don't comply with Joliet and ISO formats described in both Nero manual and in MP3 head unit manual yo will get a loud shreik on some tracks - most noticable on dance tracks.

Hope this helps.

Some of the 1st gen MP3 headunits don't play DJ mixes very well. This isn't necessarily related to the ripping + encoding process - it's just how some players are. JVC and Pioneer have the problem, although on Gen 2 players Pioneer have eliminated the issue.

None of Kenwood's MP3 players have the "silence" problem, I run DJ mixes in the car all the time (Ministry of Sound, Major Flavas, Phat Mix etc) without nary a pause. :)

As for your clipping problem with Joint Stereo, that could be related to the computer you're encoding with. What kind of soundcard are you using? How much memory do you have?
Does the file sound ok on the computer, or just bad on your headunit?
If you play the file off the CD, via the computer, does it sound ok? If it sounds bad there, then it's a problem with your encoding. If it sounds bad on your headunit, then that's a real problem.

It may also be the media that you're using! If you use CDRs designed for audio only, then they will SUCK if you are writing data (MP3) files to them. Likewise if you have songs on cheap audio CDs, and you try and rip them, you will end up with clipping and noise.

I had to image and reburn a bunch of audio CDs that I'd made, just so I could correctly extract the audio to encode into an MP3.

Sorry bit long winded! :)

thanks for the replies chaps.

The playback of the MP3's which I experienced jittery sounds with work fine when played back on my PC. Thats why I made the assumption the Alpine MP3 decoding technology was a little flaky. As I say, once encoded in standard stereo all was fine.
I've been using Audio-Catalyst to encode such MP3's. I know this application is a little dated but you kinda stick with what you know how to use :-).

Lightning101:
I didn't know you could specify time gaps between data tracks. I thought this was only relative to audio e.g. Disc-at-once mode to eliminate the gaps.

Huffer,
RE:Playback track gap.
Interesting, so I take it the gap/pause whilst reading the next track was a known issue. I have to admit, I thought it was a bit p1ss poor the way a quality head unit by Alpine would briefly stop the music so to read the next track... surely have they not heard of buffer ahead technology.

WHAT ENCODERS DO YOU GUYS USE AND CDR S/W?

How do Audio ONLY cd's differ from data ONLY cdr's?


Thanx again.

I use exact audio copy. Don't bother with anything else :D

this is correct! You shouldn't have any gaps...so that means the gap insertion is due to the headunit. JVC's Gen 1 have the same problem.

I don't know if it was an issue for Alpine or not - I'd have thought that a company so heavily involved in the US soundoff scene would have picked up on the "seams" in DJ mixes. The concept is quite similar to the minidisc scene, where the disc is essentially one continuous soundbite with "track marks" inserted to make skipping forward/back much easier.

The seamless transition between MP3 files was one of my top criteria when looking for a suitable player. That and looks, ease of use.

I use Audiocrusher for ripping and encoding. It's pretty good. I usually rip at least to 192kbs, and 320 if I'm listening to something with classical lines. When burning to CD-R/W (I only use CDR/W's as they're reusuable) I use Easy CD Creator 5. It came free with my laptop and it works.

not entirely sure, but I've found that if you use low quality, cheap media, you end up making nice coasters.

I use the Imation brand for all my backups, archives and data CDs. I also use Imation CDR/Ws for my MP3 + data cds, and also my music CDs.

I also burn at either medium or low speeds, and if I'm making a music only cd (CDA) then I make an image of the CD first, and burn that.

I'd suggest try playing some of your "faulty" recordings on other MP3 players (like Kenwood/Pioneer/Blaupunkt) and compare that.

Lightning, The pause in nero is for Audio tracks! MP3 is writen as data, the player induces the delay as it reads the next part of the data file