www.yampp.com has plans for a DIY mp3 player (several, actually) and i got really interested in building one. but then i read on the discussion forum that the Yampp-3/USB had a hard drive, so it could hold a lot of songs, but it had a horrible battery life, the yampp-7 was designed for portability, but it uses crappy CF cards. newegg has an 8GB one for $1,219.50 CF $152.4375/GB 100GB 2.5" ultra slim line HDD $1.52/GB see why i want a HDD? does anybody have a linky to a site with the info on a (reasonably) lightweight, HDD based, battery operated, DIY mp3 player (basically a homebrew iPod)
mp3ar.com used to have some good stuff, but they haven't been going for a couple of years, and the site is now detagged. Try the Google cache?
you could use a cf based hard drive, like this http://www.andymack.com/mylog/pivot/entry.php?uid=standard-868 or just buy a microdrive
Depending on how clued-up you are, you could make one using a VS1011, a high-speed PIC, a 3x8 PIO chip for the IDE interface and a few other bits. But it would be a lot of work.
here is a 20gb 1.8 in hd, IDENTICAL to the one used in the 20gb gen3 ipod. There are 40gb and 80gb versions too, but not from that site try froogle This is an ATA (IDE) hard disk, NOT a compact flash one. Good luck with this! ch424
i kinda want to stay away from CF and other memory cards, 2.5" hard drives are fine with me. i couldn't find www.mp3ar.com in google cache. nohope4me, there is nohope4me if i try to design one myself, i am almost a complete n00b to electronics ch424, thanks for looking, but the only board I've managed to find is sized to fit over a 2.5" hdd, so a 1.8" won't change much. that thing is cool though.
Most of these projects use the CF in an IDE interface format, so the main differnece is the format (coding for larger than say 4gig). But also a decent one will buffer the MP3 (or a large portion) into SRAM, so the HDD can spin down (also shock protection). This is all very simple, and if you actually understand the MP3 player (rather than wanting a solder by numbers kit). The changes are simple. Problem is making it look neat, nice case etc.
http://www.myplace.nu/mp3/yampp3u.htm does have a very simple schematic, but i know nothing about digital audio. the hardware part at least. modifications wil require major hand-holding, unless there is a howstuffworks.com, or a similar website thingy about this. that is my major source of info.
The problem i had when i made my MP3 player (I actually used one of them neto atmels with integrated mpeg-decoder, as well as PIC with external one, i used damnit can't find the chip i used, it has a DAC + MPEG decoder in one package). Anway as i was saying the problem i have had was noise, quality. It was all post DAC chip errors, the sound was always low end. i like Hi-Fi, but i'm not stupid audiofile, i think the problem was PCB noise, and low quality caps(or wrong value). in short i never found why it was so fuzzy.
with my luck, if i fiddle with the design i'll hit the brown noise in a crowded room while I'm giving a speech
ooh! ooh! ooh! what what what? What's it called? How did you get it? Would that be the VS1101? That's the main one I think, but many people use the STA013, which needs an external DAC. I actually met the CEO of ST (the company that makes the STA013), and he said he'd post me a few if I emailed him. I'm still waiting... TheAnimus you are an electro/coding guru! :respectSmilie: (BTW, your website doesn't work) ch424
no, no, no, it's "audio file" he was mistaken for a real media file the other day, he had to brutally beat the fool i don't blame him TheAnimus, if you really want to figure it out, you could try a variable capacitor and tweakuntil the fuzz is gone. but you probably knew that. the way i figure it, anyone who knows how to build a mp3 player knows the simpleist way (meaning i figred it out) to fix it.
Chip was an 89C51SND1C-EL can't remeber how i got it (i think i perswaded someone to give me one, as the one left in the project box has SAMPLE printed on it ) Err honestly can't remeber it was a few years ago! Was a damn small qfpn package only form its in, i never got round to properly using this chip! comming soon..... since 1999 i've got about 10 articals on it, they're all so seperated and dis-jointed! i've a short attention span! i got board. As for audiophiles, i didn't emply all were stupid, u mearly assumed (incorrectly, ergo, stupidly) i ment all. Which does really sum up the group, i only have a problem with the ones that really don't understand their subject, and waste money on it (only because i don't get the money). These are people who buy £35 gold plated scart leads from dixons. So for me the fun of making an mp3 player, then making a CF interface, then a Smart Media Card (which i promptly lost the code for )
yeaah i just spent 100 quid on a set of componant cables from my dvd player to my new TV... it does make a difference on new stuff
yes there is quality cables as oposed to non, but when ur dealing with TV quality signals (non-hidef) there is no need for gold connectors, their not been jiggled about! and when there £40+ its a rip off! Its short distance, i'm not saying get a good one thats got proper sheilding, but don't get ripped off, PAL-M dosen't move *that* fast, and if your really taking it all to that extent then worry about how smooth the psu is in the DVD player thats driving the analouge conversion.
Been looking into this. The biggest annoyance I can see with the MPEG decoder chips is that they only do mp3 (lots of my music is in FLAK e.t.c). Using some rought gestimates e.t.c I believe one of the new Atmel arm7 "8bit MCU replacement" chips should have enough grunt to decode FLAC and definatly enough for mp3. On the alanlog output stage I would recomend keeping the analog ground separate from the digital ground (or only connect them at one thin point), keep the analog components on a designated part of board and pass a ground plane beneth them. If there is still hiss it means your filters are incorrectly designed.
Yes, i wanted to add a ground plane, but didn't have time or money or enthusiam to do so! (the circuit was pretty much perfect i felt, so the intresting bit was done). i've been thinking of using a dsPIC, built in AC'97 interface support if u wanna have a bash at making one lynx, i'll be more than happy to help! (myself i wouldn't mind a HDD based one, that was good, ie had oodles of RAM to cache the song to, so the HDD could fully spin down).
How did you solder it? It's got 80 pins along 4x 14 mm of side! Just patience? Or did you pay to use an SMD machine? ch424
