Topic: Tascam DR-70D 4-channel audio recorder (Part 4)

[Gutbucket]

I still haven't discounted this unit for ambisonic recording. Am I right about the preamps still not being gangable? Any word on a firmware update for that?

Regarding the slate function, is the slate tone written directly to the files? I'm thinking this could be used to level match the recordings in post. (If not, how are you doing it now?)

As a side, is it possible Tascam will never release a gang function firmware update because it might cause some sales loss from the DR680? This is the only feature keeping me from the 70d.

Thanks for your thoughts

Regardless of SD card issues, which presumably will be ironed out eventually, as an ambisonic mic user recording raw A-format output from the mic, I cannot recommend choosing a recorder with gangable gains strongly enough!!  The DR-680 is a far better fit for an A-format output ambisonic mic, trust me on this.

An acceptable alternative is to use a four channel preamp which provides global gain control across all channels while keeping the relative interchannel gains equal, eliminating the need to adjust gain on the recorder at all, once it's input sensitivity has been calibrated to match the preamp's output level and the input sensitivity across all channels have been adjusted to be as close as possible to each other.  And after doing that you might consider removing the input level adjustment knobs from the recorder to prevent accidental adjustment which will knock it out of calibration.

Yes, recorded test tones can work for gain matching adjustment on the computer later, but it's a PITA!  I do that occasionally when I need to use the R44 instead of the DR-680.  The recorded tones need to be made at the end of the recording session, while the channel gains on the recorder are still set exactly the same as they were during the session, preferably immediately afterwards.  You can record tones beforehand, but that only works if you don't need to make ANY gain adjustment on the recorder at all while at the gig.  If you need to adjust a few times during the gig, you need separate test tones across all tracks for each adjustment.

And, unless the internally generated tone provided by the DR-70D is injected prior to input gain adjustment on each channel (meaning the tone level needs to be affected by the input gain adjustment on each channel), the reference tone will need to be provided by an external source.  So if you plan to use the internal tone for gain matching, first confirm that is the case.

But again, use a DR-680 (mark I or II doesn't matter) and your recording life will be much simpler and more enjoyable.

[Gutbucket]

I haven't been following the thread closely, so forgive me for the suggestion if it's been covered, but has anyone tried reverting to the previous firmware which was widely in use before the problems started happening?  ..assuming it can be reloaded.

Not sure what was addressed with the most recent firmware, but it couldn't have been more critical than reliable card writing.

Steve, you may be the obvious one to try doing this, since you aren't currently relying on the machine for regular recording and have less to loose if it bricks.

[Life In Rewind]

Im still on the original firmware - and getting the glitches.

I've recorded 4 channels on these cards before without problem - and now have trouble with 2 channels.

[willndmb]

I posted yesterday that my Lockn recordings (2ch 24/48, etc.) appeared good. Check that. At least one file corrupt.

Willndmb, if this data gathering exercise is for 4ch users only, please advise.

no its not for 4 channel only however, a lot of the issues are at 4 channel recording so imo i would like to hear if good or bad results happen on 4 channels vs 2 as well.

[pohaku]

Im still on the original firmware - and getting the glitches.

What version is your firmware?  Versions 1.02 and 1.10 are still available for download on the Tascam site.  Current version is 1.11.

[stevetoney]

I haven't been following the thread closely, so forgive me for the suggestion if it's been covered, but has anyone tried reverting to the previous firmware which was widely in use before the problems started happening?  ..assuming it can be reloaded.

Not sure what was addressed with the most recent firmware, but it couldn't have been more critical than reliable card writing.

Steve, you may be the obvious one to try doing this, since you aren't currently relying on the machine for regular recording and have less to loose if it bricks.

They person that I refunded for the unit I bought back tried all of the firmware and reported that it didn't resolve the issue.

[2manyrocks]

Pulled out the box where I bought a 70d (still new in the box) as part of the $199 special that went on a while back to see what card was in there.  It's a Sandisk Ultra microSDHC UHS-1 8 GB card which I've never used.

Got me to wondering...I had a 70d from another seller and had no issues with it at all.  I haven't touched the one I got as part of the $199 special to know if it's good or bad.

Tonedeaf and others having card issues, did you get your 70d as part of the $199 special?  Is there something about a particular production batch of these 70ds that we ought to be looking into?

Maybe do another survey on this detail?

[Life In Rewind]

Im still on the original firmware - and getting the glitches.

What version is your firmware?  Versions 1.02 and 1.10 are still available for download on the Tascam site.  Current version is 1.11.

Mine says - System Version: 1.00 0037

[Life In Rewind]

Pulled out the box where I bought a 70d (still new in the box) as part of the $199 special that went on a while back to see what card was in there.  It's a Sandisk Ultra microSDHC UHS-1 8 GB card which I've never used.

Got me to wondering...I had a 70d from another seller and had no issues with it at all.  I haven't touched the one I got as part of the $199 special to know if it's good or bad.

Tonedeaf and others having card issues, did you get your 70d as part of the $199 special?  Is there something about a particular production batch of these 70ds that we ought to be looking into?

Maybe do another survey on this detail?

Mine came from B&H - but early, before the special.

[stevetoney]

OK thanks for that explanation about buffer.  Two followup questions, if you don't mind. 

First question is, when the write speed falls under the minimum speed during your testing, what is the resulting effect on the resulting recording?  Digi-noise?  Skipping?  I just want to confirm with 100% certainty that what you're seeing when the speed drops too low is the same as what I'm experiencing in my unit.  Thanks.

As far as I'm aware, cards that don't meet this threshold are dropped from further testing, so I don't know what the end-world result is of continuing to record in this case.
We are looking at improving this, though I'm not privy to the potential details.

Thanks for the response.  You said in your response that Tascam is looking to improve.  From a customer perspective, if you're looking to improve, start by providing answers to the logical questions users have posed in this thread.  The most important question that hasn't been answered, but has been asked repeatedly is, why do cards work in other units with the same data transfer requirements, but they don't work in this unit?  The response you provide is simply that users need to use a card on a small list.  But in responding this way, you haven't provided users with any level of confidence that this answer is going to resolve the issue.  I don't want to spend another $70 or $80 on a card and go through another month, two or three of doing what amounts to Tascam's beta testing with possible similar results only to find out that this is basically just a stall until these units are beyond their warranty period. 

If you find this response to be confrontational or non thankful to your continued response to questions, it's not intended to be.  It's the reality that I'm faced with by the lack of legitimate responses you've provided to the efforts people have made here to get to the bottom of this issue...basically on Tascam's behalf.

The second question is just the engineer in me that's curious...I think some people have commented in this thread that a certain card works fine in their DR680 but not in the DR70D.  Is it a logical conclusion then that there's more buffering memory in the 680 and that's why they're not seeing the same issues on the 680? 

Unfortunately I don't know, I've not seem the design docs for either products, and no other cases of increased recording failure has been reported so far, so there's no failure report doc yet.   Given that the DR-680 does more channels to start with, it makes sense that it would have a bigger buffer though.
Circumstantial evidence though still points at the card having slowed down since being used previously.  If someone has a card from that exact test, they should do an erase format and try it again, and let us know what card it was (if it was on the DR-680 tested media list).

I'm confused...and frankly somewhat bothered by your response.  On the one hand you're saying you don't know the answer about buffering.  I assume you must know something about these units or you wouldn't be responding.  So for this answer, you aren't tech saavy enough to give me a straight answer, or even suggest that you'll try to find out the answer, so you just say 'I don't know'.

On the other hand, you're tech saavy enough about these units to tell me that there's circumstantial evidence for cards slowing down as the reason for issues.  First off, what circumstantial evidence is there?  The DR70D has only been out for a few months and nobody that I know of has reported chronic issues with the 680 or any other multi-track recorder having problems with cards going bad with use.  Sure, it happens, but it's not chronic, so your explanation just doesn't hold water as an excuse for the DR70D, which has only been on the market for a short time.  So what is this evidence you speak of?

The only circumstantial evidence I know of is being compiled by this group in a database.

[stevetoney]

Pulled out the box where I bought a 70d (still new in the box) as part of the $199 special that went on a while back to see what card was in there.  It's a Sandisk Ultra microSDHC UHS-1 8 GB card which I've never used.

Got me to wondering...I had a 70d from another seller and had no issues with it at all.  I haven't touched the one I got as part of the $199 special to know if it's good or bad.

Tonedeaf and others having card issues, did you get your 70d as part of the $199 special?  Is there something about a particular production batch of these 70ds that we ought to be looking into?

Maybe do another survey on this detail?

I bought two of them under the $200 deal.  One for myself and one for another person (who doesn't have a credit card).  The purchases for both were from B&H and were one day apart.  Mine has problems, his doesn't.

[tomuo]

I'm out of here.

If anybody has glitch problems with cards on the tested list, please contact me directly.
The advice about slowed down cards was for cards not on the list.  Tested cards are good even when slowed down.

[2manyrocks]

Pulled out the box where I bought a 70d (still new in the box) as part of the $199 special that went on a while back to see what card was in there.  It's a Sandisk Ultra microSDHC UHS-1 8 GB card which I've never used.

Got me to wondering...I had a 70d from another seller and had no issues with it at all.  I haven't touched the one I got as part of the $199 special to know if it's good or bad.

Tonedeaf and others having card issues, did you get your 70d as part of the $199 special?  Is there something about a particular production batch of these 70ds that we ought to be looking into?

Maybe do another survey on this detail?

I bought two of them under the $200 deal.  One for myself and one for another person (who doesn't have a credit card).  The purchases for both were from B&H and were one day apart.  Mine has problems, his doesn't.

Presumbly they filled orders from existing inventory that could have been produced at different times.   There's a 7 digit label on the bottom of mine.  I have no idea if trying to match up those digits will lead to anything useful or if it's a wild goose chase. 

My interpretation of tomuo's "tested cards are good even when slowed down" is the tested cards should work.  If they don't, then a warranty claim would seem to be in order.

[Life In Rewind]

Ok - here's something interesting...not sure I've seen this mentioned.

I was just looking at some of the files on my card.

I recorded a show Aug 2 - headliner set was 4 channel - internals and a pair of condensers.

Went home and transferred the show to my PC. Recordings were perfect.

This weekend - I used the card again for a few sets a festival - just 2 channels.

All those sets have glitches - and now the set I recorded in August - also has glitches!

I went to my other PC - and the files I transferred right after the Aug show are clean.

All subsequent files have glitches - and now the pre glitch files have glitches!

WTF?

[ButchAlmberg]

Interesting you say that Life In Rewind. I just posted about a bad recording from Lockn. Funny thing is... my girlfriend said we listened to that set once and it was fine. Yesterday, all shitty.