MAS-Player and 68030

[Xanxi]

Hi.

I have a MAS-Player. I think it's a Pro version hence it has both parallel and serial connectors.

I though it was suffucient for full hardware support of MP3 decoding, but it's not, on my current computer at least (A1200 - Blizz 1230@50MHz + FPU - 64 MB FASTRAM). I tried reading a 320 kbs 44 KHz MP3 from an USB key, from the hard drive or from RAM: but i only get choppy output while multitasking, and most of the time when doing nothing.
I use the simple program which comes with the MAS Player, with 0 priority and 2MB buffer.

Any idea what i am doing wrong?

I remember to have used this flawlessy some years ago but was on an Apollo 1260.


Subsidiary question:
I connect the output from the MAS Player to the "line in" connector of my Logitech speakers, while in the meantime, the Paula output is connected to the main jack entry of these speakers. Could there be any danger for the amiga circuitry (some kind of dangerous electronic loop or so)?

Thanks for your help.

[doctorq]

Both the Mas standard and Mas pro has serial and parallel connectors.

As for playback, have you tried with MP3s with a lower rating than 320 kbs? I have used mine with AmigaAMP and anything higher than 192 kbs MP3s gave problems with audio output.

[Franko]

Hi.

I have a MAS-Player. I think it's a Pro version hence it has both parallel and serial connectors.

I though it was suffucient for full hardware support of MP3 decoding, but it's not, on my current computer at least (A1200 - Blizz 1230@50MHz + FPU - 64 MB FASTRAM). I tried reading a 320 kbs 44 KHz MP3 from an USB key, from the hard drive or from RAM: but i only get choppy output while multitasking, and most of the time when doing nothing.
I use the simple program which comes with the MAS Player, with 0 priority and 2MB buffer.

Any idea what i am doing wrong?

I remember to have used this flawlessy some years ago but was on an Apollo 1260.


Subsidiary question:
I connect the output from the MAS Player to the "line in" connector of my Logitech speakers, while in the meantime, the Paula output is connected to the main jack entry of these speakers. Could there be any danger for the amiga circuitry (some kind of dangerous electronic loop or so)?

Thanks for your help.

I used to have the MasPlayer, it worked perfectly 99% of the time on my old A1200 + GVP030/50Mhz board. At the time though I was reading mp3's from the HD and not via USB, but doing too much multitasking would cause the choppy effect.

I think reading your mp3s via USB could cause problems, if your Amiga is only 030 & less than 50Mhz CPU Speed. I can play mp3's on my A1200 060/PPC from HD without problems using Songplayer via the custom built amp in my A1200 and it only uses about 25% of the processor speed.

[Tenacious]

Hi.

 I tried reading a 320 kbs 44 KHz MP3 from an USB key, from the hard drive or from RAM: but i only get choppy output while multitasking, and most of the time when doing nothing.
I use the simple program which comes with the MAS Player, with 0 priority and 2MB buffer.

Subsidiary question:
I connect the output from the MAS Player to the "line in" connector of my Logitech speakers, while in the meantime, the Paula output is connected to the main jack entry of these speakers. Could there be any danger for the amiga circuitry (some kind of dangerous electronic loop or so)?

Thanks for your help.

Gee Whiz!  Where do you find Mp3s encoded at 320 kbs?  I think most of mine are at 128kbs.  Can you hear the difference in the 2 bit rates?  I enjoy music,but, I'm not an audiophile.

My Amigas are offline, currently.  Otherwise, I would DL a Mp3 at 320kbs and try it out.  MasPlayers, though wonderful, are built around an old chip.  I wouldn't be surprised to find out that 320 kbs is too much for the chip or the Amiga's parallel port (the serial port only supplies power to the MasPlayer).  

I have often heard of ppl happily using MasPlayers at their full fidelity with 7 MHz A600s (haven't tried this myself, yet).

SUBSIDIARY ANSWER:  I don't know the specifics of your speakers.  Often, audio switching hardware only switch the left and right signals of different audio sources, not the grounds.  This is usually desirable.  So, yes, you probably do have a ground loop. You could try unplugging the Paula source and checking playback.  This is probably not the problem, though.  I have a Radio Shack 4 input switcher (selecting MasPlayer, Paula, CDRom, & a Macintosh) supplying one speaker system, no sweat.

Ground loops are bit unpredictable.  There are a number of issues, one of the worst is if one of the components connected together has a chassis ground at a different voltage than the others.  In that case, the signal ground could be carrying substantial current, maybe at 60 Hz (hum).  Sometimes the components can be de-coupled with capacitors.

[Xanxi]

Indeed, things are much better with a 128 kbits MP3.

Actually, tenacious, i can hear a great difference between 320 and 128 kbits. 128 kbits is a bit too compressed to my hears and i usually prefer 160 kbits, the best compromise.

I have noticed that after i unplug the output from the MASPlayer to the speaker, the miggy seems to have lost some audio channels from Paula when i listen to some mods. After a warm reset, everything is back to normal.
So it's probably not a good choice to use the line in entry of these speakers and i will go after a good switcher.

Anyway, how can we distinguish a MAS Player from a Pro version and what is the actual difference?

[AndyC]

Back in the day, I used a MAS Player with a Blizzard 1230 Mk4 50MHz and 16 megs of RAM. I Played 192k MP3s from my SCSI CD-Rom with no problems.

I challenge anyone to notice the difference in audio definition at any higher rate than that...

AndyC

[Karlos]

Back in the day, I used a MAS Player with a Blizzard 1230 Mk4 50MHz and 16 megs of RAM. I Played 192k MP3s from my SCSI CD-Rom with no problems.

I challenge anyone to notice the difference in audio definition at any higher rate than that...

AndyC

Actually, it rather depends on the audio and the other compression options. I have some stuff that sounds different at 192 and 256kbps.

[kolla]

People still use mp3?

[Tenacious]

People still use mp3?

I use what I have.  What do you have/use?

@ Xanxi

I've often wondered if the quality of an Mp3 is not more dependent upon the quality of the source and the recording skill as opposed to the bit rate.  I will try someday recording the same material at multiple bit rates to see if I can hear the difference.

That Paula channel loss thing you mentioned may be the best argument yet for avoiding a ground loop.  Sometimes chips accumulate damage and then fail like an avalanche.  Food for thought.

[Franko]

Before I converted all my music Cds to mp3s a few years ago (using nothing more than Lame & my Amiga) I carried out various tests on all the different bit rate encodings.

I found personally that using a VBR at between 128 to 225 bits, produced the best quality for file size ratio.

The playback quality really all depends on what your using to play the mp3s on and what type of speakers & amp you use. Having tried lots of different set ups I found that my cheap Alba MP3 player gives far superior sound than an expensive Sony one when played back on the same equipment...

[Heiroglyph]

I like to use 192k when I use mp3.  I've seen many devices have trouble with higher bitrates.

[LoadWB]

Before I converted all my music Cds to mp3s a few years ago (using nothing more than Lame & my Amiga) I carried out various tests on all the different bit rate encodings.

I found personally that using a VBR at between 128 to 225 bits, produced the best quality for file size ratio.

The playback quality really all depends on what your using to play the mp3s on and what type of speakers & amp you use. Having tried lots of different set ups I found that my cheap Alba MP3 player gives far superior sound than an expensive Sony one when played back on the same equipment...

Jah. I only ever used VBR for my MP3s.  It made a huge difference and in most cases didn't make the files much bigger, with the exception of more complex songs.  I have for several years kept my collection in FLAC so I can convert at a whim.  These days I use M4A.

[Rod_cl]

Where can i still buy a mas player. I've never been able to find one.
Best regards from Chile

[Xanxi]

So, no one answered yet about the differences between the normal and the pro version??

[Tenacious]

So, no one answered yet about the differences between the normal and the pro version??

IIRC, there is little difference in the 2 versions.  Maybe it was the casing or the audio out (2 phono plugs vs. one 0.125 stereo plug).  I believe they both used the same chip, both were powered by a serial pass-thru connector.

The chip is the big deal, supposed to be hard to find.