Topic: Tascam DR-70D 4-channel audio recorder (Part 3)

[dogmusic]

I have had this bookmarked for a long time, I should probably link to it in the FAQ:

https://www.gearslutz.com/board/remote-possibilities-acoustic-music-location-recording/960891-new-very-compact-4ch-recorder-tascam-2.html#post10842631

You might quote a few posts there - but there's a lot of out of date speculation there and stuff about a 70Dmkii - that seems wrong...lets not perpetuate that.

The JW posts seem the to be the most relevant.

Yes, well actually JW was the one who was perpetuating the mkII rumors.  You'll see I asked him directly about it since it seems so strange.

I think that was a confusion of his with the DR680MKii.

[ts]

Oops on me about the factory preamps being mentioned, but I don't see a link to the modification?

I dont think anyone has a Busman Modded unit yet - at least no one reporting here.

And - I don't think Busman has reported his mod specs...

Cheesecadet had his done locally - and to his (and Jim Williams) specs - JW isnt doing the mod business-wise...

So - its a bit of a mystery...dont think there is a link...

Here's a DR70 Busmod: http://taperssection.com/index.php?topic=172797.0

[2manyrocks]

http://taperssection.com/index.php?topic=172109.msg2131985#msg2131985

Photos and parts list for the JW mod posted by Cheesecadet in post 13 of the second thread. 

[Cheesecadet]

There is no Tascam DR-70D MKII.

JWmod consists of 5 opamps and 8 poly caps.

Jim Williams is not performing any mods at this time.  After many lengthy emails and pictures sent, I have his detailed instruction on how to perform his mod.  I can forward this info in its entirety to those who may want it, although, I did post it in the threads so that would probably be easier for you to find and you wouldn't have to wait on me to get back to you.

I asked Busman about his components used in his mod to compare to the JWmod and he does not want to give out this info.  I can appreciate this as it is his business.

[willndmb]

There is no Tascam DR-70D MKII.

JWmod consists of 5 opamps and 8 poly caps.

Jim Williams is not performing any mods at this time.  After many lengthy emails and pictures sent, I have his detailed instruction on how to perform his mod.  I can forward this info in its entirety to those who may want it, although, I did post it in the threads so that would probably be easier for you to find and you wouldn't have to wait on me to get back to you.

I asked Busman about his components used in his mod to compare to the JWmod and he does not want to give out this info.  I can appreciate this as it is his business.

could be the same based on the info jw supplied 

[Cheesecadet]

There is no Tascam DR-70D MKII.

JWmod consists of 5 opamps and 8 poly caps.

Jim Williams is not performing any mods at this time.  After many lengthy emails and pictures sent, I have his detailed instruction on how to perform his mod.  I can forward this info in its entirety to those who may want it, although, I did post it in the threads so that would probably be easier for you to find and you wouldn't have to wait on me to get back to you.

I asked Busman about his components used in his mod to compare to the JWmod and he does not want to give out this info.  I can appreciate this as it is his business.

could be the same based on the info jw supplied 

What do you mean?  What could be the same?

If you are referring to an MKII version of the DR-70D, I was told there was not one even being considered at this time by Tascam directly.

[willndmb]

There is no Tascam DR-70D MKII.

JWmod consists of 5 opamps and 8 poly caps.

Jim Williams is not performing any mods at this time.  After many lengthy emails and pictures sent, I have his detailed instruction on how to perform his mod.  I can forward this info in its entirety to those who may want it, although, I did post it in the threads so that would probably be easier for you to find and you wouldn't have to wait on me to get back to you.

I asked Busman about his components used in his mod to compare to the JWmod and he does not want to give out this info.  I can appreciate this as it is his business.

could be the same based on the info jw supplied 

What do you mean?  What could be the same?

If you are referring to an MKII version of the DR-70D, I was told there was not one even being considered at this time by Tascam directly.

I'm saying maybe he got the same info as you from jw and the mod is the same

[Cheesecadet]

There is no Tascam DR-70D MKII.

JWmod consists of 5 opamps and 8 poly caps.

Jim Williams is not performing any mods at this time.  After many lengthy emails and pictures sent, I have his detailed instruction on how to perform his mod.  I can forward this info in its entirety to those who may want it, although, I did post it in the threads so that would probably be easier for you to find and you wouldn't have to wait on me to get back to you.

I asked Busman about his components used in his mod to compare to the JWmod and he does not want to give out this info.  I can appreciate this as it is his business.

could be the same based on the info jw supplied 

What do you mean?  What could be the same?

If you are referring to an MKII version of the DR-70D, I was told there was not one even being considered at this time by Tascam directly.

I'm saying maybe he got the same info as you from jw and the mod is the same

Busman only told me that he uses different opamps than JW and he believes his own mod would sound better.  To each their own I guess.  I'm sure Busman probably based his mod on JW's regardless though...I could be wrong, who the hell knows  

[Ozpeter]

he believes his own mod would sound better.

But is it more accurate?  "Sounding better" is a totally subjective thing - for one person it might, for instance, involve exaggerated (but not correct) bass response, which another person might dislike.  On the other hand, it might involve a measurable improvement in signal to noise ratio. 

If I were ever to pay out money for any mod to any device, I'd want to know exactly what I was getting in terms of outcome, and how it could or has been measured.  Often, there just seems to be so much vagueness when these mods are discussed.  And of course there's the whole "law of diminishing returns" thing - I don't doubt you can make improvements to any audio device, but are the improvements sufficiently audible to justify the effort and expense, and could the cost be better put towards (for instance) a better mic instead?

[Cheesecadet]

Exactly. It is very subjective.  I went with JWmod because I have always been impressed with his mods and it gives a better top end detail and lower noise floor. Those are the exact two things I was looking for in a mod and JWs reputation in the biz speaks for itself.  I use various pres to change "flavor" when needed. I don't believe Busman has specified what his mod achieves, has he?

[2manyrocks]

One way to find out what the Busman mod consists of is to unscrew the case of one of his units and look inside. 

[Cheesecadet]

True.  He said he used an Analog Devices opamp but wouldn't specify which one.  Not sure if he is using poly caps or if it is just an opamp swap.  Maybe we can get an owner of a busman modded unit to take a quick peak inside and let us know?

One would be able to determine the opamps used pretty easily by just unscrewing the outer case.  Determining if poly caps of some sort are used is a bit more involved as it would require complete disassembly of the unit.

Regardless of whatever opamps are being used in his mod there is more that goes into deterring if something is "better" or not besides a basic opamp.  Power consumption, signal to noise ratio, detail, noise floor, etc, etc, etc.

I would be curious to know exactly which opamp he is using though.

[voltronic]

he believes his own mod would sound better.

But is it more accurate?  "Sounding better" is a totally subjective thing - for one person it might, for instance, involve exaggerated (but not correct) bass response, which another person might dislike.  On the other hand, it might involve a measurable improvement in signal to noise ratio. 

If I were ever to pay out money for any mod to any device, I'd want to know exactly what I was getting in terms of outcome, and how it could or has been measured.  Often, there just seems to be so much vagueness when these mods are discussed.  And of course there's the whole "law of diminishing returns" thing - I don't doubt you can make improvements to any audio device, but are the improvements sufficiently audible to justify the effort and expense, and could the cost be better put towards (for instance) a better mic instead?

These are both excellent points.  I would feel much better about getting a unit modded if I could see measurements before / after.  It could confirm / disprove what you "think" you're hearing after listening to your modified unit.

Of course, it would be REALLY nice if Tascam published real measurements for this unit in the first place, or a reviewer took the time to measure it properly.  I've read quite a few reviews, but have not seen one that does this.

[Joshua_G]

...  I would feel much better about getting a unit modded if I could see measurements before / after.  It could confirm / disprove what you "think" you're hearing after listening to your modified unit.
…

It looks like the above is written out of the assumption that conventional measurements (frequency response, THD and SNR) are giving full and accurate picture about how any audio gear sounds.
Alas, this isn't the case. This is in my experience of (now retired) sound engineer and electronics engineer (and an ardent audiophile).
Many of us know that the proper way to choose a microphone for a certain task is by the way it sounds (subjectively), not by the way it measures. There are very accurate microphones which are used for measurements, however, generally speaking, those measurement microphones aren't the best suited ones for recording.

[voltronic]

...  I would feel much better about getting a unit modded if I could see measurements before / after.  It could confirm / disprove what you "think" you're hearing after listening to your modified unit.
…

It looks like the above is written out of the assumption that conventional measurements (frequency response, THD and SNR) are giving full and accurate picture about how any audio gear sounds.
Alas, this isn't the case. This is in my experience of (now retired) sound engineer and electronics engineer (and an ardent audiophile).
Many of us know that the proper way to choose a microphone for a certain task is by the way it sounds (subjectively), not by the way it measures. There are very accurate microphones which are used for measurements, however, generally speaking, those measurement microphones aren't the best suited ones for recording.

I actually wasn't making that assumption.  Measurements don't tell the whole story necessarily, but they would take some of the mystery of what has been done to these modified vs. stock units.