Topic: Archos Gmini 120

[Kelso]

right if it's one meter long, you shouldn't have trouble even if the cable isn't designed for digital transfert. But if you want to be sure use video cable that has the necessary bandwidth and is 75 ohm, like a digital cable should be, and stay away from any magnetic source.  I doubt the cable causes the drops.

[JasonSobel]

while the supplied digital cable is cheap and flimsy, it does specify right on the cable that it is a 75ohm cable.  I haven't had time to make my own 75ohm S/PDIF RCA to mini yet, but I don't think the cable is causing the problems I'm experiencing...

[rustoleum]

I attempted to do some testing this weekend.  Unfortunately, I didn't get anywhere near as close as you guys did.  I was unable to get the thing to lock onto any signal via spdif.  I fed it the coax out of my minime and a singal from my d100 and both times it was unable to lock on.  I was able to do some line-in recording, although I didn't dwell on it long as I don't have intention of ever using the line-in option.  I'm not giving up yet, but hoping one of you guys who is farther along can answer some questions for me that might get me further along:

1) The recording format seems to be set to MP3 all the time... I was unable to change this to WAV.  Is that correct?  Is it supposed to detect that the incoming SPDIF singal is a WAV and then automagically dump a WAV to the harddisc?  

2) What is this 'supplied' digi cable you guys mention.  I got the little adapter that gives a an output and a SPDIF/line-in option, but there were no other cables other than the USB interface.  I ended up using a radio shack phone plug to 1/8" mono.  I was able to use the cable (along with an 1/8" to phono adapter) to feed my d100 from my MiniMe, so I don't think the cable is the problem.

3) I have to push the shit out of the 'Right' button to get it to work.  This tells me their quality control ain't that great.  Anybody have any other obvious flaws like this?

I guess that's all for now. If anyone could chime in on these questions or share any other experiences I'd appreciate it.  Hopefully I get over this stumbling block and can get to some accuracy testing.

Rusty

[timP]

did you update the latest firmware? it allows you to record in wav and may allow you to lock into it w/ yr mme...

[timP]

http://www.archos.com/download/firmware.html
here it is... did you already have this?
hope not........

when you have this firmware installed, you should be able to pick mp3 or wav and the kbps..

[rustoleum]

I did grab that but I'll admit that I didn't see anything happen after I copied it to the root drive and rebooted.   I'll try to update it again tonight.  Thanks!

Rusty

[JasonSobel]

Rusty,
the latest version of the firmware is 1.5.0
they said that if you had anything less than 1.2.0, you should update to that before updating to 1.5.0
Mine came with 1.2.0 already installed, so I just went ahead and upgraded to 1.5.0 with no problems.

you can check which version of firmware you have by going into the system information section...

the supplied cable is a set of RCA to an 1/8" input.  there are actually three RCA plugs, red/white, for line level recording, and a yellow RCA for the S/PDIF.  All three RCA's terminate into the same 1/8" plug, which, if you look, is divided into 4 areas...

[Riley]

OK, I have some time tonight, so I'm going to do some testing.

I only have a UA-5 for A to D, which resamples.  I also don't have any way to get a digital input into my computer except through my Gmini.  So here's the plan:

I record from mics through the UA-5 into both my D8 and the Gmini.  Then I transfer the recording from the D8 to the Gmini and then get both recordings off of the Gmini and compare for bit accuracy.

That's the only way I can think of to get some test data with the equipment that I have.  Anyone see any flaws with this methodology?  The only thing I can see that could introduce error is if the signal from the D8 to the Gmini isn't a good signal.

Riley

[MattD]

Errors on DAT playback could be an issue as well. The results are likely to be inconclusive.

-Matt

[Riley]

Yes, that's essentially what I meant by getting a bad signal from the D8.  Sorry, should have clarified that.

Well, the test is done.  I recorded 15 minuites of audio from my UA-5 to both the Gmini and DAT at 44.1 kHz.  I then transferred the recording from the DAT to the Gmini and then copied both files to my computer.  I took both WAV files, inverted one and mixed it with the other to find any inconsistencies.  Result:  YES there were some inconsistencies.  They were pretty much the same as those reported earlier.  I have a nice picture of them to post but I can't figure out how to get it into this message.  Any advice?

To rule out whether or not the DAT was the problem, I listened to the origial recording from the Gmini at the points where the inconsistencies occoured.  I haven't checked all of them, but YES at least some were present in the Gmini recording and were audible.  As mentioned earlier, they sound like little clicks or pops in the audio.  They aren't very long, though.  I check the length of a couple of inconsistencies, and each was just one sample in length.  Some of them were in both left and right channels, but others were in just one.

Well, what now?  Is it time to talk to Archos and battle with tech support to see if we can make them understand what's going on here, or should we do a little more testing first?

On the upside, my Gmini has been running for almost 6 hours now without dying on me (while playing music on headphones or recording).  I read a post somewhere that someone did in response to prople complaining about only getting 3 hours or less out of the battery.  He said to "prime" the battery by running the thing dry right out of the box, fully charging it, and running it dry again several times.  That's pretty much what I do.  He claimed that he got about 10 hours out of it.  We'll se how long this thing runs, but it's doing pretty well so far.  I'll do another post when it dies to let everyone know how long it went.

Riley

[timP]

dang... not the best news about the pops and such... I already have 1 so-so recorder in the IRIVER......
only have 4 days to take my ARCHOS back, and am not sure what to do...
this could be formware or it may be the HD, either way it's a bunch of cash.....

[Riley]

HEY!!  Here's something really interesting.  I have been playing around with the file I created that shows only the pops.  I amplified it so that each pop was at peak level so I could see them better and checked the amount of time between them.  There were a total of 16 pops in the 15 minuite recording.  Here are the lengths of time between each pop in seconds.

19.3
19.9
19.3
38.6
96.6
38.1
39.2
38.1
77.3
77.3
19.95
57.5
121.5
38.1

Notice anything?  Every single number except for 1 of them is almost exactly a multiple of 19.3 seconds.
This indicates to me every 19 seconds there was something that happened during recording that gave an opportunity for an error to occour.

ALSO, THERE'S MORE.  While recording, there is a little red light that blinks occasionally during some kind of hard drive operation.  I listened to a WAV file on the  recorder and timed how long it was between when the light starts to flash.  Here's the times in seconds

34
38
37
35
39

Again, about every 38 seconds it does some kind of hard drive operation.  38 is also a multiple of 19.

Could these pops maybe be related to some kind of hard drive writing operation that occours during recording?

Riley

[Riley]

Oh, yeah, I forgot to mention.  The battery finally died.  It lasted just about 7 hours.  That's about as long as I'll need to record anything.  Might not need an external battery after all.

Riley

[Riley]

Here's another thought.  This thing has an 8MB buffer, right?  If it is writing at 44.1kHz, that's 180.15kBytes/sec or 1411.2kbits/sec.  At that rate the buffer will fill after about 44 seconds.  It will need to write before then to keep the buffer from overflowing.  Then it would make sense to start writing at about 38 seconds.

I don't know.  I might be out on a limb here.  It would be interesting though to try the same test while recording at 48kHz.  This might decrease the amount of time between hard drive writes.  Then we could check to see if the amount of time between the pops decreases.  YEE GODS!  LOOK AT THE TIME.

Maybe tomorrow.
ZZZZZZZZZZZZZZZZZZZ
Riley

[jerryfreak]

picked one of these up today. first off, I gotta say its heads above the creative products if only for the following reasons:

1. logical fat32 volume, no special software/drivers required
2. installing new firmware and plugins are a snap
3. since it acts like a drive, you can decode shns to wavs written directly on the drive, whereas with the nomad, you must decompress, and then load the wavs onto the device
4. coax beats optical any day of the week
5. size and weight are better than the jb3 (who ever decided a device needs to look like a cd player anyway?)
6. the gmini acts as a self-powered usb2 drive (for those of us who use laptops, this is a real nice feature
7. The power jack is the same size and polarity as my mini firewire external drive, which draws 5V off a usb>coax cable. This charges the gmini fine. Always nice to have gear that shares common cables.
8. It can actually write a 96K file (albeit 16/96). If I switch the spdif sample rate from 48 to 96, it starts writing data in double time without errors. Too bad its limited to 16-bit. it obviously has the potential to do 24/48 and possibly 24/96.

the only downside is the fact that you must use that goofy adapter jack to get spdif in. unfortunately, the spdif signal is coming in one of the odd proprietary 'wing' jacks on the side of the trrs jack. but at least we can make a custom trrs plug to take spdif right to the adapter jack and lose the multi function line in/spdif in cable.

one more downside is that it doesnt playback wav files seamlessly, but this will come in time I'm sure.

I'll report more results as they happen


I've been doing tests, and so far everything looks good with my unit (out of the box+1.50 firmware), I have run 40 minutes out the ad2k with no errors whatsoever, and also did a short test with the v3 (4 minutes) that worked perfectly. I'm currently doing a longer test with the v3 now.