[The Godfather]

I am evaluating the possibility of building a car mp3 player with a Mac motherboard. Do you know if the 680X0 cpus can play mp3s? What's the minimum required for this?

Why a Mac MP3 player? Because I am planning to use speech to announce the track title, boot it off an old small SCSI HD and play MP3s from a SCSI Zip drive. Macs are inmune to sudden power downs, I would control it from an ADB gamepad.

Would it be possible to start such a system from a floppy?

[blizaine]

I tried playing them on a 100Mhz 601 PPC and they played but they would skip alittle, like the CPU couldn't keep up. I would suggest anything less. Last I heard, you had to have a PPC to play mp3's.

I don't think you could boot the system from a floppy because the extenisions needed to play MP3's would be to big. And the floppy would be sloooow.

Hope this helps...

[spinkb]

Depends on what MP3 player you use. I used to play MP3's with Vamp, MacAmp, and SoundPlayer on a 6100/60. NONE of them skipped unless I did some sort of disk activity where the program got starved for CPU time. You will need at least a PPC though. I don't know of any 68k mp3 players. 68k machines just didn't have enough power.

You could boot from a floppy...but you wouldn't be able to load the things you want...like sound manager, and speech manager. Plus it would suck to have to wait a couple minutes before it would even play. Use a small HD.

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Complete Full Scale FTP Server : CrushFTP ---> http://crushftp.bizland.com/ by Ben Spink

Use a 6100/60, do a custom install of a base system for this computer (8.6 MAX, try 7.5.3 or 8.1 first). Pick an MP3 player you want to use (soundjam isnt that good because of the way the keyboard is used to control it). Move the MP3 player into the system folder along with any other files you need for it. Use resedit and make the mp3 player applicatio you want to use have the same type and creator as Finder. Move the original finder out, and rename the mp3 player finder. Once you restart the mp3 player will be the only thing running. You can buy a small fan and strap it on the heatsink of the 601 to make it cooler. Try www.mp3car.com..... It seems DOS is the best way to play mp3s since it has a fast start time and you can just turn off the computer. You can also buy logicboard as small as 2.5 hard drives to make a really small box to fit in your glovebox. A 6100 logicboard is big. And uses SCSI hard drives which are expencive.

This is a cool idea. But you need a ppc I suggest a ppc 6100 motherboard. It and it's power supply are small and quiet. Since you will be running a stripped system it shouldn't skip. It has onboard scsi. Here is one for 35$ ( http://cgi.ebay.com/aw-cgi/eBayISAPI...item=322779752 ) Instead of booting from a floppy use a scsi drive. OS 8.0 with hfs standard. small scsi drives are very cheap. Here is a link for a 700MB for 6$ ( http://cgi.ebay.com/aw-cgi/eBayISAPI...item=316940775 )

Where in the vehicle were you planning to put this and also how are you planning to power it? Cooling might be a factor.....(More fans direct on processor and on power supply) A peltier junction is also an option. It is an active cooling device (gets cold!)

Are you going to build an enclosure or use the Mac case?

I would love to hear how it turns out. feel free to email me at [email protected] Also if you take pics of how you did it I will be happy to host a "How To" page on my Server. I run my own private server through my cable modem. http://www.macmeisters.com

There are NO 68k mp3 players. While it would be possible to make one, mp3 playback is mostly an fpu function. Most 68k fpu's (if they even have one(i.e. not 68LC040)) are terrible. Even if someone made one that would run on 68k (no one with the ability to make one would) the performance would be terrible. I am in the process of building a Performa 6115 w/ G3 upgrade into my car. I will post my progress as i go.

BlackFly
[email protected]

The best option is probably not a 6100 although that is fast enough to run mp3s if you use SoundApp PPC. The perfect mac for Car MP3 would have a few other characteristics: IDE drive for inexpensive storage and 44 KHz sound out. I tried a Performa 6300 (enough CPU, cheap Hard drive) but all the early performas (before the 6360) have 22 KHz sound out which makes them sound muddy. It's a shame because you can find old performas for $100 and they have small, power frugal motherboard that supports IDE. Of course you might think that with the car noise, 22 KHz is sufficient. I missed the high end when I was listening in my house.

IDE is important because you can get huge drives that could hold your whole collection and not have to deal with swapping media (CDs or Zips).

The best Mac for a high end MP3s would probably be a Motorola StarMax--it's the cheapest mac available with IDE and 44 KHz. Performas would be next best and a 6100 would be last. A 6100 does have 44 KHz output but it's expensive to buy a big SCSI hard drive.

I think a car MP3 should aim to have all your CDs on the Hard Drive because fiddling with disks is a waste of time and can be dangerous while driving. You could pretty easily set SoundApp up to randomly play songs from your whole collection. Or with a gamepad and some addtitional software you could make 'stations' of different types of music.

As you can see, I've done some thinking and experimenting with this.....

Nate

Nateinator: I am very interested in doing this and have some questions. How would you easily add new music and set up stations to your config (without a monitor)? I can see Applescript doing this but that's beyond my scripting abilities.

How are you planning to supply power?

I got excited about a cd of mp3's for a second but I'll bet that a cdrom would have all sorts of skipping trouble on a car as they are not built for shock absorbtion

What about heat and extreme cold? My area of the midwest USA ranges in temp from -25 to 115 degrees.

To all interested, a note: Many Macs won't boot without a monitor attached the way to get aroung this is to attach a monitor cable adapter to the monitor port

For anyone looking for a simpler solution:

I saw a Kenwood CD/MP3 car stereo in the latest Crutchfield. It's pricey (about $650), but much easier than trying to hack a mac to do the job.

Tony

[baliset]

I see you're recommending a 6100 board, but have you seen how *big* they are? Unless you're building a custom enclosure, you'd have no choice except to stick it in the boot (uh.. that's "trunk" to you Americans). Then there's the matter of how stable a regular HD will be in a bumpy environment. My advice- use a Powerbook. Adantages:
1. Easy to power.
2. Built in HD is shock-rated for mobility.
3. Much, much more compact.

BTW- why not use one of the portable MP3 players like Rio and use an in-car stereo system with an input jack?

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Nathan Zamprogno,
Manager, Baliset Solutions
[email protected]

[Bartman]

Hi,

I have soe ideas that I'd like to share. Why don't you burn a system CD + MP3 files, and place an alias of your MP3 player into the (Startup Items Folder). Your System Folder should be minimum (boot faster / more stable).
IMHO, this way is better than using a hard drive because you can prepare your MP3s CDs at your home and use them directly. I think if you use an IDE/SCSI hard drive you will have to take it out and plug it in a Mac which may be inconvenient or tedious.
You can even hide the whole unit somewhere under the seat and place the CD drive in the dashboard (plus power key / controls).
You can go with removable storage (Zip / Orb / MO) instead.
If someone suggested this earlier, sorry for the "headaches".

Tell us on what you decide on and what you build, some people will follow.

Good luck

[MacOS761]

I agree that SoundApp is very good for this kind of purpose. It doesn't require any Extensions, which is a plus. I use it on a 5200/75 LC, which I believe is less powerful than a 6100/60. SoundApp is especially good because you can tweak the way it accesses the HD (actaully, I use Jaz disks). I set the double buffer really low (but not zero) to minimize any possible skipping.
The thing about setting up another app as the "finder" is cool, I was just thinking that should be possible. The only problem is turning the computer off...? (BTW, if you do that and quit the psuedo-finder app, it would automatically start itself again!)
Floppy boot could be possible with a version of system 7, but what's the point? If you're really concerned about performance, a good Applescripter (not me) could do something with a RAM disk, I bet.
Hope that helps.

[The Godfather]

I like the ideas on the two last posts:

* to burn a System+MP3 CDROM and use it in your bootable CD drive, no HD required, no VM, no corrupted files.

* I am witness that SoundApp puts a very light load in my G3. 761, did you say you played MP3s in your 5200/75 LC???

* someone selling his/her StarMax MB?

I add this:

* a purpose-specific launcher/controller could be written in Real Basic really easy. I would start that as soon as I get convinced that Macs can make good MP3 players.

* I am on the search of the under-$100 car MP3 player. I've found PCs that could make this goal, do you think Macs could do it too?

* I have just had this idea: the Sony Playstation has built-in hardware MPEG decompression. Will that make it capable of playing specially prepared MP3 CDROMs?

The Godfather

[MacOS761]

No kidding Godfather! I amaze even myself... here's my setup:
- 5200 / 75 LC running a 75 MHz 603
- 1 GB Jaz drive
- SoundAPP (2.5.x ? whatever's current)
- Mac OS 8.5 fairly standard install MINUS SoundManager (QT 4.1.2)
I found that the SoundManager extension is responsible for lots of unwanted slow-downs, skips, quiet moments. Apparently, it tries to process the audio that SoundApp puts out for some reason, slowing the whole process down, so I disabled it. Now it's great.
As I mentioned before, the Double Buffer (Pref->Play) is set at 64, the lowest except None which loads the whole song into RAM. I believe this basically means that it reads in 64 byte chunks, so they are small but frequent, whereas 256 would be large but not often. Small chunks keep the Jaz from lagging, and you can only hear the little skips if you listen hard or on particlar songs (mostly the quieter variety).
Also in the Play prefs is the sampling rate. I tried setting this lower to see if performance would increase but it didn't. I figured that the reason was if it's trying to read a 44 KHz sampled recording at 8 KHz, it has to skip over 4 samples, which would require more work than just skipping every other (max rate on my machine is 22KHz). The lesson is to set this as close to the native recorded rate as possible.
I think that covers all the important details on my setup.
I think you could *theoretically* make a Mac mp3 player for under $150 anyway, if not $100. I say theoretically because projects like that always cost more than they should. I have a friend who's making a PC laptop into an mp3 player, but I haven't talked w/ him in a while. You should be able to rustle up a 6100 motherboard, smallish HD, and make a
box for fairly cheap, though. A Rio type player can be had for under $100 though.
As far as PlayStations, it would not be worth the effort. First, you need to get special disks. Second, you would have to write a "game" to act as a driver for the MPEG hardware. Plus, the hardware is probably for video MPEG, but it could include mp3 support... who knows? Still, a
neat idea but not very simple.
I wish I had a StarMax CPU. A new G4 this summer is consolation though.

Speaking of the Performa and 22kHz, is there anyway to work around that to get 44.1kHz? I just picked up an old Performa and a 13 Gig IDE HD JUST to use as a mp3 jukebox. I never even though about the 22kHz... Can that sound output hardware be replaced, or is there any sort of soundcard that can be used with the Performa 6320CD (maybe through SCSI)? (It has not PCIs). Man, I wish I'd though of that before.

[The Godfather]

Whew! Bringing up a topic from MONTHS ago...

Well, I have just found The Best Thing (TM) in MP3 playing. It is called SoriTong, it is for PCs and it barely uses 1/3 of the CPU time of a Pentium 100, running Window$ 95.

Check it out in http://showcase.netins.net/web/phdss...p3_players.htm
Start Soritong and set the audio quality to "Medium". The sound quality doesn't drop in my opinion.

I think I could do this MP3 player with a 486/50 motherboard. Aren't these worth a dollar a dozen now?