Topic: Tascam DR-70D 4-channel audio recorder (Part 6)

[voltronic]

^ I thought you and I had buried the hatchet, TD?

My comment didn't single anyone out specifically.  Lots of people were involved with this over the last four or five months.

So as far as I'm concerned, there's no hatchet, only lessons to be learned.  My hope in making the comment above is that people that were active in this saga will look back and reflect on what they'd do differently.  I'm not proud of some of the things I said at points along the way (emotions get in the way of rational thought sometimes), but in the end I'm really glad that I had a role in pushing Tascam and not being satisfied with their interim explanations and/or 'solutions'.  As poorly as I think they handled this overall, I do have to give Tascam credit for forging ahead with this fix.  Perhaps they learned some lessons as well.

Anyway, the bottom line is we're all on the same team and we can use our collective 'voice'.  A unified team is stronger than a fractured one.

Fair enough.

I think what would be really great is if Tascam could take a page out of Zoom's customer service playbook (never thought I'd say that) and really listen and respond to users in a timely and thorough fashion.  Would I be correct in saying that for those of you that have had problems with this and other Tascam products that the the customer service end is almost equally as frustrating as the actual problems you've had with the product?

Also I'm hopeful that they are getting things on track, but we'll have to see if that bears out.

[voltronic]

Here's a pretty nifty bag specially designed for the DR70D, if anyone's interested.  Check out the demo video.

http://www.bhphotovideo.com/c/product/1200016-REG/k_tek_kstg70_stingray_bag_for.html

Very slick - I just put it at the top of the gear bag list on the 70D FAQ page.  I wish you could actually fully enclose the unit though without the cutouts for the 1/4"-20 mount and the built-in mics.  But for its intended use it seems great.

[aaronji]

Would I be correct in saying that for those of you that have had problems with this and other Tascam products that the the customer service end is almost equally as frustrating as the actual problems you've had with the product?

More so...

[stevetoney]

Would I be correct in saying that for those of you that have had problems with this and other Tascam products that the the customer service end is almost equally as frustrating as the actual problems you've had with the product?

More so...

Yes.  I could spell it out, but it's really just Customer Service 101, especially dealing with people that are providing feedback on new products. 

[2manyrocks]

Unless someone really sees a reason to upgrade the firmware I am going to stay put where I am. I have not had any issue using the PNY Elite card and have used the deck for both 2 and 4 channel recordings.

If it's working for you, I wouldn't upgrade, either.  I think it would be better for Tascam and its customers  if Tascam more clearly stated what the firmware improves. If the firmware is intended to fix write timeout errors, make that plain as day.  It gets everyone on the same page.   

Wouldn't pay $95 for a bag for a $200 recorder.    

[justme]

I picked up a new 70D the other day to try out and see how it works for me.
Anyway, I installed a set of totaly new Eneloop Pro, just out of the charger and played around with it. Its firmware was still on rev 1.01 so I dowloaded the latest firmware 1.13 and updated it.

I then noticed that the battery meter read very low even though the NiMH cells should be pretty full.
After a changed it between "Alkal" and "NiMH" it seemed that there's a bug in the settings.

Tascam apparently have mixed up Alkal and NiMH settings.
When the battery type is set to Alkal though NiMH is used the battery meter is showing a higher reading and vice versa.
It should be the other way around.

Is this a know bug?

Anyway, I emailed their support and asked about it.

[soundsinteresting]

Had the same experience with my new DR70, after installation of fresh ENELOOP PRO 2500mA and updated to ver 1.13.
Sofar it looks like I have a stable recorder (8Gb card) but my battery indicator seam to behave badly and it certainly looks like Alkaline/NiMh selector has been switched or algoritme is weak. most of the time it shows 50% left.
I have another  peculiar thing that does no harm but is yet annoying in menues.
I do not like that the phrase "MIC" is used for diferent things in menues, it should be distinguissed where needed (internal MIC, external etc..)
If ch 3/4 is set up for internal "MIC"'s it is still possible to select phantom power on 3/4.
I assume that is not intentional and does not show on display but is yet selectable in menu INPUT/INPUT GAIN.

I am missing PREREC of at least 5 secs which should be no big deal as any small recorder like M10 has a similar functionality.
it has been decribed before but I also would like to have Monitor to each channel / channelpair.
It looks like my version is very sensitive to switching phantom powered devices which has caused malfunction that needed repowering, but any technician would know that this of course should be done unpowered

Despite of this, this little device behaves like a charm and i have been playing almost glitchless with several different setups and input sofar.

[2manyrocks]

Welcome to the discussion.

It is interesting and concerning that we have two new posts reporting inaccurate battery metering with the new firmware.  So do we have one step forward and one step back with version 1.13?    

The way the 70d uses batteries, it's helpful to use an external 5v cell phone battery pack like the Ravpower or something like that. Then the 70d will run for hours with no worries.

 

 

[soundsinteresting]

Welcome to the discussion.

It is interesting and concerning that we have two new posts reporting inaccurate battery metering with the new firmware.  So do we have one step forward and one step back with version 1.13?    

The way the 70d uses batteries, it's helpful to use an external 5v cell phone battery pack like the Ravpower or something like that. Then the 70d will run for hours with no worries.

I use a powerbank rated 10000mAh so batteries are not a big worry, inside eneloops are used for backup just in case.

[voltronic]

Welcome to the discussion.

It is interesting and concerning that we have two new posts reporting inaccurate battery metering with the new firmware.  So do we have one step forward and one step back with version 1.13?    

The way the 70d uses batteries, it's helpful to use an external 5v cell phone battery pack like the Ravpower or something like that. Then the 70d will run for hours with no worries.

I actually wonder if this is even new behavior, or was an existing problem none of us noticed before because most of us are probably running off external power, especially if you're powering external mics directly.  I have only ever had alkalines in my unit, and they are only there as emergency backup so I've never had a chance to check the battery setting before - it's always been set to alkaline, and my external battery is attached to the unit at all times so out of habit I power on the pack even when I'm just messing around with menu settings and not recording. 

I'm still on 1.12 so I can try popping in rechargeables and see if the setting doesn't stick with that firmware version also.

[stevetoney]

I just recharged my Energizer NiMH and measured all four batteries at 1.40V on a multi-meter (well one battery actually read 1.41V).  The battery indicator on the DR-70D is reading full.  I have firmware v1.13 installed and confirmed that my battery setting is on NiMH, so as far as I'm concerned the indicator is working fine for NiMH batteries.

Before reaching any firm conclusions about the battery indicator, I'd suggest other users measure the actual voltage and make sure that the indicator reflects accurately what the voltage of the batteries is saying, rather than just assuming that a fresh recharge should result in a full reading.  It's possible that your charger isn't taking your Eneloop batteries all the way up to 1.4V each. 

Also, I'm not sure any conclusions should be reached that Alkaline and NiMH scales are switched based on just changing the setting between NiMH and Alkaline with Eneloops installed and then observing how the indicator changes.  I'd rather see someone measure the voltage from a fresh set of alkalines, then install them with the unit set on 'Alkaline' and correlate the reading to the scale.  (1.5V for each battery should equate to full for Alkalines)

[soundsinteresting]

I just recharged my Energizer NiMH and measured all four batteries at 1.40V on a multi-meter (well one battery actually read 1.41V).  The battery indicator on the DR-70D is reading full.  I have firmware v1.13 installed and confirmed that my battery setting is on NiMH, so as far as I'm concerned the indicator is working fine for NiMH batteries.

Before reaching any firm conclusions about the battery indicator, I'd suggest other users measure the actual voltage and make sure that the indicator reflects accurately what the voltage of the batteries is saying, rather than just assuming that a fresh recharge should result in a full reading.  It's possible that your charger isn't taking your Eneloop batteries all the way up to 1.4V each. 

Also, I'm not sure any conclusions should be reached that Alkaline and NiMH scales are switched based on just changing the setting between NiMH and Alkaline with Eneloops installed and then observing how the indicator changes.  I'd rather see someone measure the voltage from a fresh set of alkalines, then install them with the unit set on 'Alkaline' and correlate the reading to the scale.  (1.5V for each battery should equate to full for Alkalines)

Ok i had to reflect a bit more of my conclusions concerning battery dislay, and after a few tests of discharging i am on retrait with battery display as a problem.
My first hasty conclusion was probably based on thinking that Alkaline would always have a larger (measured) voltage during discharge than NimH, but this show not always to be a fact.
If you look at attached picture of a typical discharging of the two types you will see that curves are crossing at maybe 25% of capacity, so before this line, my assumption was  ok, but after crossline this is not a valid assumption.
So conclusion is that tascam display is probably ok for the 75% remaining capacity but not of the first 25%  (who cares?).
It is probably not a very accurate display anyway, due to the flat discharge curve of NiMh batteries but indicative at least.

I have no experience with other than the latest v1.13 sofar, and i am in no way a battery expert, so take it from there  .

[stevetoney]

I just recharged my Energizer NiMH and measured all four batteries at 1.40V on a multi-meter (well one battery actually read 1.41V).  The battery indicator on the DR-70D is reading full.  I have firmware v1.13 installed and confirmed that my battery setting is on NiMH, so as far as I'm concerned the indicator is working fine for NiMH batteries.

Before reaching any firm conclusions about the battery indicator, I'd suggest other users measure the actual voltage and make sure that the indicator reflects accurately what the voltage of the batteries is saying, rather than just assuming that a fresh recharge should result in a full reading.  It's possible that your charger isn't taking your Eneloop batteries all the way up to 1.4V each. 

Also, I'm not sure any conclusions should be reached that Alkaline and NiMH scales are switched based on just changing the setting between NiMH and Alkaline with Eneloops installed and then observing how the indicator changes.  I'd rather see someone measure the voltage from a fresh set of alkalines, then install them with the unit set on 'Alkaline' and correlate the reading to the scale.  (1.5V for each battery should equate to full for Alkalines)

Ok i had to reflect a bit more of my conclusions concerning battery dislay, and after a few tests of discharging i am on retrait with battery display as a problem.
My first hasty conclusion was probably based on thinking that Alkaline would always have a larger (measured) voltage during discharge than NimH, but this show not always to be a fact.
If you look at attached picture of a typical discharging of the two types you will see that curves are crossing at maybe 25% of capacity, so before this line, my assumption was  ok, but after crossline this is not a valid assumption.
So conclusion is that tascam display is probably ok for the 75% remaining capacity but not of the first 25%  (who cares?).
It is probably not a very accurate display anyway, due to the flat discharge curve of NiMh batteries but indicative at least.

I have no experience with other than the latest v1.13 sofar, and i am in no way a battery expert, so take it from there  .

When using NiMH rechargeables, it's good to know the shape of the discharge curve.  Since the center part of the discharge curve is flat, the display will go from full to half quite fast.  Then the display stays on half for a long time.  Once the batteries start to expire, the final bars go from half to empty quite fast. 

I've been caught offguard before because I will look at the display and it will still show the batteries are at half, then ten minutes later my device is dead.  Because of that, I like to conduct run time tests on my equipment so I have a better idea of exactly how long the device runs.  It removes the guessing about when the batteries will run out, so that I can change them if necessary at a convenient time, such as between songs or during setbreak or whatever.

[soundsinteresting]

I just recharged my Energizer NiMH and measured all four batteries at 1.40V on a multi-meter (well one battery actually read 1.41V).  The battery indicator on the DR-70D is reading full.  I have firmware v1.13 installed and confirmed that my battery setting is on NiMH, so as far as I'm concerned the indicator is working fine for NiMH batteries.

Before reaching any firm conclusions about the battery indicator, I'd suggest other users measure the actual voltage and make sure that the indicator reflects accurately what the voltage of the batteries is saying, rather than just assuming that a fresh recharge should result in a full reading.  It's possible that your charger isn't taking your Eneloop batteries all the way up to 1.4V each. 

Also, I'm not sure any conclusions should be reached that Alkaline and NiMH scales are switched based on just changing the setting between NiMH and Alkaline with Eneloops installed and then observing how the indicator changes.  I'd rather see someone measure the voltage from a fresh set of alkalines, then install them with the unit set on 'Alkaline' and correlate the reading to the scale.  (1.5V for each battery should equate to full for Alkalines)

Ok i had to reflect a bit more of my conclusions concerning battery dislay, and after a few tests of discharging i am on retrait with battery display as a problem.
My first hasty conclusion was probably based on thinking that Alkaline would always have a larger (measured) voltage during discharge than NimH, but this show not always to be a fact.
If you look at attached picture of a typical discharging of the two types you will see that curves are crossing at maybe 25% of capacity, so before this line, my assumption was  ok, but after crossline this is not a valid assumption.
So conclusion is that tascam display is probably ok for the 75% remaining capacity but not of the first 25%  (who cares?).
It is probably not a very accurate display anyway, due to the flat discharge curve of NiMh batteries but indicative at least.

I have no experience with other than the latest v1.13 sofar, and i am in no way a battery expert, so take it from there  .

When using NiMH rechargeables, it's good to know the shape of the discharge curve.  Since the center part of the discharge curve is flat, the display will go from full to half quite fast.  Then the display stays on half for a long time.  Once the batteries start to expire, the final bars go from half to empty quite fast. 

I've been caught offguard before because I will look at the display and it will still show the batteries are at half, then ten minutes later my device is dead.  Because of that, I like to conduct run time tests on my equipment so I have a better idea of exactly how long the device runs.  It removes the guessing about when the batteries will run out, so that I can change them if necessary at a convenient time, such as between songs or during setbreak or whatever.

I agree that battery display cannot be used for production time validation, but can only be used as an indication of disaster ahead.
Using external power is even worse. My connected USB powerbank has only 4 LED's to show status so you really need to know your runtime here, but it seems to switch glitchless with internal batteries.
Thankyou for your feedback.

[kleiner Rainer]

Hi all,

estimating state of charge from a simple voltage measurement is close to impossible. There are too many variables: temperature, load current, and internal resistance to name a few. In the "good old days", tape decks had VU meters. Battery powered ones had a button to switch one of them to a battery meter - not with a voltage scale, but with a sector telling you full or empty - my Marantz CP430 did this. My Sony WM-D6C had four LEDs to show me battery voltage or level. You had to learn to understand what your recorder wanted to tell you - this has not changed in the last 30 or so years 

Another point to keep in mind is that current consumption of modern recording devices is not constant over changing supply voltage! Back then only a few parts of a tape deck were supplied with a stabilised voltage - the capstan motor, maybe the bias oscillator or sensitive preamps. The rest was simply powered off the batteries - mostly C or D cells (my marantz used three of the latter). So current drain dropped with dropping voltage.

Not so nowadays: our portable computers we call "decks" or "recorders" often use an elaborate array of high-efficiency switchmode converters to power the different subcircuits. The interesting part is that a DC/DC converter has the astonishing property to present the battery with a partially NEGATIVE input resistance! In simple terms: since the converter tries to keep the input power constant, current rises when voltage drops. I will give you an example:

Assume a recorder with four phantom powered mics, drawing about 3W of power overall. A good, modern, power supply of the switching type has an efficiency of 90%, so the battery has to deliver 3W/0.9 = 3.333W. Battery type is a Lithium polymer cell with 3.7V nominal, voltage goes from 4.2V (full) to 3.2V (empty). Now we can calculate current drawn from the cell:

4.2V: 0.79A
4.0V: 0.83A
3.8V: 0.88A
3.6V: 0.93A
3.4V: 0.98A
3.2V: 1.04A

Those numbers are also valid for the typical USB power bank.

Problem: the internal resistance of most electrochemical systems rises when they get discharged. There is a tipping point when the battery simply cannot sustain the ever rising current demand of the converter - the problem tonedeaf described.

My advice: keep backup batteries handy, use external power (power banks with as much capacity as possible), check your rechargeables often (there are chargers that can check capacity - since they discharge to a certain switchoff voltage, high internal resistance also shows as low capacity). Keep battery contacts clean, wipe with denatured alcohol: this keeps contact resistance and power loss down. If you record outdoors in cold climate: keep your rechargeables warm - put them in your pocket.

Greetings,

Rainer