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Gary Eickmeier Gary Eickmeier is offline
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I thought I was doomed.

Just finished shooting the second half of Mulan, a stage play that we were
hired to shoot. Used the Zoom on a tripod to get the up-front sound from the
stage. First half, worked flawlessly. Second half complete, shut down the
camera and go down to retiieve the recorder. It was put in the HOLD position
for recording so that no one could shut it off on me. So what happens when
you try to stop recording or any other operation is that it tells you you
are on the HOLD position and must rmove the HOLD if you need to do some
task on it. Well, if you move the HOLD button down, you arrive in the SHUT
DOWN BYE SEE YA position, which is what happened. Then I started sweating
because I thought it didn't have time to transfer the data to the memory
card before shutting down. Super bad trend if they are trying to eliminate
complicated usage instrucions.

But it DID transfer all the data. Beautiful recording of the close-up dialog
on stage, which was very hard to hear in the audience due to a cheap sound
system. So now the video will have better sound than the play did live. I
used a touch of compression in Audition in editing, but the sound on AGC was
very good anyway. Saved the video.

Also did a surround sound recording of a dance band with the Zoom. Used 3
spaced omnis (AT 2050) for the front, Zoom MS for the rear. Worked quite
well technically, but quite a pain to edit and convert to DTS surround
files. Not the best example either, with very small audience & hardly any
rear sound to listen for.

Anyway, a good report on an inexpensive little "non - professional" recorder
as discussed above doing a job for me and coming through even with operator
screw-ups.

Gary Eickmeier


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Mxsmanic Mxsmanic is offline
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Gary Eickmeier writes:

Well, if you move the HOLD button down, you arrive in the SHUT
DOWN BYE SEE YA position, which is what happened. Then I started sweating
because I thought it didn't have time to transfer the data to the memory
card before shutting down.


I'm sure that the switch isn't really any kind of on/off switch. It would just
send a signal to the OS to start shutdown. And writing any remaining data out
to the card would be a standard action for the OS before it actually shuts
down. Any kind of gadget that shut down without writing out all updates to
files would be a really bad design.
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Gary Eickmeier Gary Eickmeier is offline
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"Mxsmanic" wrote in message
...
Gary Eickmeier writes:

Well, if you move the HOLD button down, you arrive in the SHUT
DOWN BYE SEE YA position, which is what happened. Then I started sweating
because I thought it didn't have time to transfer the data to the memory
card before shutting down.


I'm sure that the switch isn't really any kind of on/off switch. It would
just
send a signal to the OS to start shutdown. And writing any remaining data
out
to the card would be a standard action for the OS before it actually shuts
down. Any kind of gadget that shut down without writing out all updates to
files would be a really bad design.


Sure - agreed - but I was composing the fattest letter to Zoom on the design
flaw on the drive home while sweating the recording. Normally, especially on
a long recording, when you press the Stop recording button, you get a screen
that says Please Wait... and it takes a few seconds to finalize, write to
card, whatever it needs to do to finish the process and get ready for the
next recording. This time, I drew the HOLD slider button down, and it
immediately said Bye See Ya (the cute little shut down language) and it was
outa here. No waiting period. All I can conclude is that it just says that,
but internally it is writing and finalizing whatever it has to do to finish
the file, unbeknownst to the hapless schmuck who just got lured into
shutdown from Hold.

Bottom line, competernt design - actually a very clever little recorder -
even if it is not a "Pro" recorder as was discussed in a thread above.

Gary Eickmeier



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Trevor Trevor is offline
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"Gary Eickmeier" wrote in message
om...
Sure - agreed - but I was composing the fattest letter to Zoom on the
design flaw on the drive home while sweating the recording. Normally,
especially on a long recording, when you press the Stop recording button,
you get a screen that says Please Wait... and it takes a few seconds to
finalize, write to card, whatever it needs to do to finish the process and
get ready for the next recording. This time, I drew the HOLD slider button
down, and it immediately said Bye See Ya (the cute little shut down
language) and it was outa here. No waiting period. All I can conclude is
that it just says that, but internally it is writing and finalizing
whatever it has to do to finish the file, unbeknownst to the hapless
schmuck who just got lured into shutdown from Hold.


Surely it's just writing to the card all along, so why would you expect it
to take a few seconds to "finalise" anything before "writing to the card"?
If anything is being done it's not to do with saving what you've just
recorded. Most digital recorders you can pull the plug (batteries) half way
through, and still keep what you've recorded up till then.
(caveat I don't own a H2n so have no idea if they do what most of the others
do)

Trevor.


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Gary Eickmeier Gary Eickmeier is offline
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"Trevor" wrote in message
...

Surely it's just writing to the card all along, so why would you expect it
to take a few seconds to "finalise" anything before "writing to the card"?
If anything is being done it's not to do with saving what you've just
recorded. Most digital recorders you can pull the plug (batteries) half
way through, and still keep what you've recorded up till then.
(caveat I don't own a H2n so have no idea if they do what most of the
others do)

Trevor.


Does anyone know what it is doing during the "Please Wait" period?

Gary Eickmeier




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Mxsmanic Mxsmanic is offline
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Trevor writes:

Surely it's just writing to the card all along, so why would you expect it
to take a few seconds to "finalise" anything before "writing to the card"?


Data is probably held in an internal buffer before being written to the card.
This buffer must be flushed to the card before the system is shut down, in
order to avoid any loss of data. Depending on the size of the buffer and other
factors, there may or may not be a perceptible delay when the buffer is
flushed.

An experiment to demonstrate this would be to pull the batteries out while the
recorder is recording sound, although that's not an experiment that I intend
to carry out. If there is indeed a buffer flush, the card content is likely to
be corrupted if the batteries are removed while recording is in progress.
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Mxsmanic Mxsmanic is offline
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Gary Eickmeier writes:

Does anyone know what it is doing during the "Please Wait" period?


Probably flushing buffers and doing other operations on the memory card. I
note that the longer the recording, the longer the "please wait" period,
although it's not a linear correlation.
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John Williamson John Williamson is offline
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Mxsmanic wrote:
Trevor writes:

Surely it's just writing to the card all along, so why would you expect it
to take a few seconds to "finalise" anything before "writing to the card"?


Data is probably held in an internal buffer before being written to the card.
This buffer must be flushed to the card before the system is shut down, in
order to avoid any loss of data. Depending on the size of the buffer and other
factors, there may or may not be a perceptible delay when the buffer is
flushed.

An experiment to demonstrate this would be to pull the batteries out while the
recorder is recording sound, although that's not an experiment that I intend
to carry out. If there is indeed a buffer flush, the card content is likely to
be corrupted if the batteries are removed while recording is in progress.


It flushes the recording buffer to RAM and updates the FAT, which is
normally held in RAM while the machine is working. As they don't use a
journalling file system, the information on where to find the file
blocks can get out of sync with where they actually are. If they used
something like extf3 or reiser FS, it wouldn't be an issue, but Windows
would be unable to read the SD card directly.

The H2 has a few seconds of buffer available which can be used as a
pre-record buffer in live situations so you don't miss the first few
seconds of a vital recording, as it records from 10 seconds before you
press Record. In this case, the last 10 seconds has to be written to the
card before it can shut down.


--
Tciao for Now!

John.
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Arny Krueger[_4_] Arny Krueger[_4_] is offline
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"Mxsmanic" wrote in message
...
Trevor writes:

Surely it's just writing to the card all along, so why would you expect
it
to take a few seconds to "finalise" anything before "writing to the
card"?


Data is probably held in an internal buffer before being written to the
card.


A relatively small amount, a few seconds worth at most.

This buffer must be flushed to the card before the system is shut down, in
order to avoid any loss of data. Depending on the size of the buffer and
other
factors, there may or may not be a perceptible delay when the buffer is
flushed.


Closing a file also requires some kind of table of contents entry to be
updated, and there may be some work needed along the lines of updating file
allocation tables.

An experiment to demonstrate this would be to pull the batteries out while
the
recorder is recording sound, although that's not an experiment that I
intend
to carry out.


If the media is removable, see what happens when you simpy pull that out.

If there is indeed a buffer flush, the card content is likely to
be corrupted if the batteries are removed while recording is in progress.


Not necessarily. There can be a big capacitor inside the box that keeps it
alive long enough for housekeeping to finish.


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Mike Rivers Mike Rivers is offline
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On 3/26/2012 7:03 AM, Arny Krueger wrote:

Closing a file also requires some kind of table of contents entry to be
updated, and there may be some work needed along the lines of updating file
allocation tables.


If there is indeed a buffer flush, the card content is likely to
be corrupted if the batteries are removed while recording is in progress.


It's possible that the housekeeping is writing something to
the card that allows the recorder to find and play the file.
So it may not be playable from the recorder, but as long as
the WAV file was properly written to the card, it would be
playable with a computer as long as the card still looked
like a disk drive.

--
"Today's production equipment is IT based and cannot be
operated without a passing knowledge of computing, although
it seems that it can be operated without a passing knowledge
of audio." - John Watkinson

http://mikeriversaudio.wordpress.com - useful and
interesting audio stuff


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Gary Eickmeier Gary Eickmeier is offline
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"Mxsmanic" wrote in message
...
Trevor writes:

Surely it's just writing to the card all along, so why would you expect
it
to take a few seconds to "finalise" anything before "writing to the
card"?


Data is probably held in an internal buffer before being written to the
card.
This buffer must be flushed to the card before the system is shut down, in
order to avoid any loss of data. Depending on the size of the buffer and
other
factors, there may or may not be a perceptible delay when the buffer is
flushed.

An experiment to demonstrate this would be to pull the batteries out while
the
recorder is recording sound, although that's not an experiment that I
intend
to carry out. If there is indeed a buffer flush, the card content is
likely to
be corrupted if the batteries are removed while recording is in progress.


Another good example is digital cameras. Notice that if you take a picture
that requires some processing in camera, it can take a while. All
photographers know that the basic process is it records to internal memory,
then writes to the card. If the internal memory is too small, you have to
wait a while after shooting a burst of exposures. I'm supposing that if you
pulled batteries or similar then you would lose your pictures. If a digital
recorder works by constantly writing to card, then that would be great,
because you would not lose much if batteries failed etc.

Gary Eickmeier


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Arny Krueger[_4_] Arny Krueger[_4_] is offline
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"Mike Rivers" wrote in message
...
On 3/26/2012 7:03 AM, Arny Krueger wrote:

Closing a file also requires some kind of table of contents entry to be
updated, and there may be some work needed along the lines of updating
file
allocation tables.


If there is indeed a buffer flush, the card content is likely to
be corrupted if the batteries are removed while recording is in
progress.


It's possible that the housekeeping is writing something to the card that
allows the recorder to find and play the file.


Yup, and us computer nerds call those things that help find and play files,
"tables of contents". ;-)

So it may not be playable from the recorder, but as long as the WAV file
was properly written to the card, it would be playable with a computer as
long as the card still looked like a disk drive.


On CDs, unclosed media is called a CD that is not finalized. The good news
is that I have 95%+ success finalizing the unfinalized CDs fall into my
hands. DVDs, not so much, but usually I have better success if I can get
access to the recorder that wrote the disc.

On USB flash drives, unfinalized media is generally not observable. The
flash drive itself may keep itself alive long enough to do the needed steps
when you unplug is, or it may use a file system that allows the finalization
to be done automatically the next time you plug it in. USB flash drives
usually have a fairly powerful 32 bit computer in their USB interface that
preserves the illusion that it is dumb, but friendly media. In fact flash is
not especially nice to work with, but its bad habits are well known and
concealing them is a very highly developed art.


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Mxsmanic Mxsmanic is offline
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John Williamson writes:

It flushes the recording buffer to RAM and updates the FAT, which is
normally held in RAM while the machine is working. As they don't use a
journalling file system, the information on where to find the file
blocks can get out of sync with where they actually are. If they used
something like extf3 or reiser FS, it wouldn't be an issue, but Windows
would be unable to read the SD card directly.


NTFS supports journals, but I assume it must be more complex to implement than
most vendors would like. Also, I suppose that FAT32 is probably understood by
way more non-Windows operating systems than NTFS. Other journalling file
systems tend to be even more exotic and are thus even more problematic to
support.
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Mxsmanic Mxsmanic is offline
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Arny Krueger writes:

A relatively small amount, a few seconds worth at most.


Well, it takes several seconds to finish. Maybe it's just the speed of the
card.

Closing a file also requires some kind of table of contents entry to be
updated, and there may be some work needed along the lines of updating file
allocation tables.


Yes.

If the media is removable, see what happens when you simpy pull that out.

If there is indeed a buffer flush, the card content is likely to
be corrupted if the batteries are removed while recording is in progress.


Not necessarily. There can be a big capacitor inside the box that keeps it
alive long enough for housekeeping to finish.


True. But I'll leave both experiments to someone else with more money than I
have.

I actually did make the mistake of turning the H4n off today while it was
still writing out the (very long) sound file that I had just recorded, but the
file was still recorded correctly, so obviously it finished up what it needed
to do before shutting down. Of course, most operating systems work that way as
long as you don't turn the power off or hit a hardware reset button.
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Scott Dorsey Scott Dorsey is offline
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Mxsmanic wrote:

NTFS supports journals, but I assume it must be more complex to implement than
most vendors would like. Also, I suppose that FAT32 is probably understood by
way more non-Windows operating systems than NTFS. Other journalling file
systems tend to be even more exotic and are thus even more problematic to
support.


NTFS is totally undocumented. Everyone outside Microsoft who has implemented
NTFS has done so through reverse-engineering the filesystem format.

The quality and performance of the reverse-engineering continues to improve
but none of the third-party NTFS implementations are anywhere near up to
the level that I would trust a job with. ntfs3g is getting there fast, though.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."


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Trevor Trevor is offline
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"Gary Eickmeier" wrote in message
news
Another good example is digital cameras. Notice that if you take a picture
that requires some processing in camera, it can take a while. All
photographers know that the basic process is it records to internal
memory, then writes to the card. If the internal memory is too small, you
have to wait a while after shooting a burst of exposures.


Not a good example, since cameras often have high speed buffer memory to
allow you to take faster burst rates than the card can handle. After a burst
the data must be written to the card which can take time. When recording
audio of more than a few seconds duration however, the data is streamed
directly to the card, and any buffer is usually quite small.

I'm supposing that if you pulled batteries or similar then you would lose
your pictures.


Yep.

If a digital recorder works by constantly writing to card, then that would
be great, because you would not lose much if batteries failed etc.


And HAS to since most audio recordings are FAR to big for the buffer memory.

Trevor.


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Gary Eickmeier Gary Eickmeier is offline
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"Mxsmanic" wrote in message
...

I actually did make the mistake of turning the H4n off today while it was
still writing out the (very long) sound file that I had just recorded, but
the
file was still recorded correctly, so obviously it finished up what it
needed
to do before shutting down. Of course, most operating systems work that
way as
long as you don't turn the power off or hit a hardware reset button.


Interesting. But I suppose it is a different story if you remove the flash
drive or memory card from the computer before the little icon says "Safely
Remove" - right?

Gary Eickmeier


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Trevor Trevor is offline
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"Gary Eickmeier" wrote in message
.com...
Interesting. But I suppose it is a different story if you remove the flash
drive or memory card from the computer before the little icon says "Safely
Remove" - right?


Depends. I've been pulling USB memory sticks from the computer for many
years without going through the "safely remove" bit, but making sure it's
not during a write. Never had a single problem. If you pull one during a
write, you may lose data and possibly need to fix the file table as well.

Trevor.


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Mxsmanic Mxsmanic is offline
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Gary Eickmeier writes:

Interesting. But I suppose it is a different story if you remove the flash
drive or memory card from the computer before the little icon says "Safely
Remove" - right?


Yes. There's no way for software to bypass a hardware change. Once the
contacts slide out of the slot, communication is lost, so if the changes
haven't been written to the card, you have a serious problem.

The same is true for removing the power, although what seems like an instant
loss of power to a human being can often still provide useful power for a fair
amount of work inside a computer. Many systems can execute short
emergency-shutdown routines with just the power that remains if a power cut is
detected. This may not extend to the slower and more power-hungry operations
of physically writing to a disk or card, though.
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Trevor writes:

Depends. I've been pulling USB memory sticks from the computer for many
years without going through the "safely remove" bit, but making sure it's
not during a write. Never had a single problem. If you pull one during a
write, you may lose data and possibly need to fix the file table as well.


Most computers will write to the USB key as soon as practical, so unless you
literally pull the key while it's being written to, you're safe. Usually the
few seconds that elapse between the last operation you perform on the key and
your hand reaching for the key are enough for all writes to be completed. Most
systems will not configure removable devices for write-into caching,
especially things like USB keys, so physical writes are initiated immediately.
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