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Nagra VII - possibly not what you were expecting
Old 1st April 2014 | Show parent
  #31
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Quote:
Originally Posted by David Spearritt View Post
Strange, my Nagra 6 allows both analog and digital inputs to be used and mixed simultaneously.
Yes, so does mine *and* my AETA 4MinX.
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Old 2nd April 2014 | Show parent
  #32
Gear Head
Quote:
Originally Posted by philper View Post
A 744T can use digital and analog inputs at the same time.

philp
The difference is that in the 744T there are 4 tracks and the spdif/bnc can be routed to any track as the xlr microphone with phantom power:

The 744T uses a flexible routing scheme to assign inputs and tracks for recording. The input matrix
allows any input to be routed to any recording track. Multiple inputs can be routed to a single track
to create mono-mixed recordings.
The 4-by-4 blue LED matrix makes it easy to view the set routing. A solid blue LED indicates an
input is assigned to a record track.
any combination of
the four inputs can
be routed to any of
the four tracks

In the Nagra 7 there is only two tracks and the AES xlr digital input can be tracked to be mixed with the xlr phantom power microphone inputs, four inputs in two tracks:

The Input Matrix is used to route the audio to the left and/or right channels. By touching the
different boxes, either input can be sent to either or both channels. The selections can be made for
both analog and digital input signals. The analog and digital “Presets” will reset the inputs to their
default mode of standard stereo."
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Old 30th April 2014 | Show parent
  #33
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Soon I will test this Nagra Seven. I will be adjudicating the mic amps, conversion and AES 42 implementation.

Report to follow. . .
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Old 30th April 2014 | Show parent
  #34
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surflounge's Avatar
Quote:
Originally Posted by Plush View Post
Soon I will test this Nagra Seven. I will be adjudicating the mic amps, conversion and AES 42 implementation.

Report to follow. . .
Thank you. Looking forward to your review, especially regarding mic pres and converters for acoustic music and location recording.
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Old 30th April 2014 | Show parent
  #35
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Larry Elliott's Avatar
Quote:
Originally Posted by Plush View Post
Soon I will test this Nagra Seven. I will be adjudicating the mic amps, conversion and AES 42 implementation.

Report to follow. . .
Looking forward to this report also!
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Old 1st May 2014 | Show parent
  #36
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I have confirmed with JO that N7 AES42 implementation is Mode 1 only - at this stage. All the hardware is there for Mode 2, but not supported at the moment (hence the SRC). The hardware is the easy part - the software is the hard part.
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Old 1st May 2014 | Show parent
  #37
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Quote:
Originally Posted by panatrope View Post
I have confirmed with JO that N7 AES42 implementation is Mode 1 only - at this stage. All the hardware is there for Mode 2, but not supported at the moment (hence the SRC). The hardware is the easy part - the software is the hard part.
Mode-1 is just adding 10V / 250mA phantom power to an AES3 input (plus adding an SRC if there is more than one stereo input).

Mode-2 needs clocking added at a minimum, plus all the other standards in Mode-2.
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Old 1st May 2014 | Show parent
  #38
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The above observation prompts the following comment, though it does not apply to the N7, but to any machines with multiple AES-42 inputs and using Mode 1 (and possibly to Mode 2) devices.

I find great difficulty in understanding how separate Mode 1 mono mics could be used as a stereo pair, giving the imperative of having sampling occuring at the same instant in both channels. This may explain the disappearance of the Schoeps (mono) Mode 1 only digital CMC body, possibly to eventually re-emegre configured like the Senn MK-D stereo body.

BTW, I am not totally convinced that even mode 2 will allow the use of separate (mono) mics on separate inputs to ensure a sufficiently stable phase relationship for coherent stereo imaging. AES-42 Mode 2 only appears to guarantee the same sampling frequency, but not phase alignment (it controls frequency with an up-down command, but the control signal rate is so low that significant short term phase drift is possible). It seems that a 2-channel body is mandatory for successful stereo operation.

If there is anyone with experience in this regard, they might like to comment (and maybe if sufficient interest, we can move to a separate thread).
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Old 2nd May 2014 | Show parent
  #39
nkf
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Quote:
Originally Posted by panatrope View Post

BTW, I am not totally convinced that even mode 2 will allow the use of separate (mono) mics on separate inputs to ensure a sufficiently stable phase relationship for coherent stereo imaging. AES-42 Mode 2 only appears to guarantee the same sampling frequency, but not phase alignment (it controls frequency with an up-down command, but the control signal rate is so low that significant short term phase drift is possible). It seems that a 2-channel body is mandatory for successful stereo operation.

If there is anyone with experience in this regard, they might like to comment (and maybe if sufficient interest, we can move to a separate thread).
I often do stereo or surround recordings with my AES42 microphones and I never encountered any phase shift. Neumann doesn't have a stereo body (yet) in their AES42 offerings, only Sennheiser does: MZD8000.
A look into a (German) Neumann paper about their implementation of Mode 2 shows they implemented full corrections of phase deviations if they occur.

"Außerdem enthält er (AES42 Receiver) einen Frequenz-Phasen-Komperator,
der den Phasenfehler zwischen dem Referenzwordclock und
dem rückerkannten Wordclock aus dem Audiodatenstrom
ermittelt. Aus diesem Phasenfehler berechnet der Regler die
Stellgröße, die über den seriellen Datenstrom zum Mikrophon
mittels eines speziellen Steuerkommandos übertragen
wird."
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Old 2nd May 2014 | Show parent
  #40
nkf
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Quote:
Originally Posted by surflounge View Post
We place one SoundField DSF-1 in center of room through Nagra VII - possibly not what you were expecting?
Frankly, I don't get at all what you mean. (English is not my first language)
I just answered the AES42 statement and don't have a Nagra at all.
My AES42 mics are connected with DMI-2p to a 744T when I'm not recording in my studio.
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Old 2nd May 2014 | Show parent
  #41
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Quote:
Originally Posted by panatrope View Post
BTW, I am not totally convinced that even mode 2 will allow the use of separate (mono) mics on separate inputs to ensure a sufficiently stable phase relationship for coherent stereo imaging. AES-42 Mode 2 only appears to guarantee the same sampling frequency, but not phase alignment (it controls frequency with an up-down command, but the control signal rate is so low that significant short term phase drift is possible). It seems that a 2-channel body is mandatory for successful stereo operation.

If there is anyone with experience in this regard, they might like to comment (and maybe if sufficient interest, we can move to a separate thread).
Yes, Mode-2 is fine and has an excellent phase relationship.

You can use two separate mode-2 microphones for stereo (as I did when I recorded four piano recital CDs with a pair of Neumann KM183-D).

To quote from my AES paper:-
Quote:
Mode-2 allows the microphones to be clocked from the receiving equipment – the clock signal is sent to the microphones as part of the data stream. Advantages include: no SRC and a constant phase relationship (close to 0°) between different mics, independent of cable length or other influences.
You can download the PDF of the paper HERE.

I wrote up the recording session here (NB: that was written quite a few years ago and I am now self employed ).

I hope this helps.
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Old 3rd May 2014 | Show parent
  #42
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Quote:
Originally Posted by nkf View Post
"Außerdem enthält er (AES42 Receiver) einen Frequenz-Phasen-Komperator, der den Phasenfehler zwischen dem Referenzwordclock und
dem rückerkannten Wordclock aus dem Audiodatenstrom
ermittelt. Aus diesem Phasenfehler berechnet der Regler die
Stellgröße, die über den seriellen Datenstrom zum Mikrophon
mittels eines speziellen Steuerkommandos übertragen
wird."
If the phase controlled clock in the microphone(s) is sufficiently stable, then a relatively low frequency update via the low rate signalling superimposed on the DPP fed to the microphone in fact turns into phase control. It depends on the loop gain of the whole process as to how stable it is. It is also not clear if it is an inherent property of the AES 42 control signal process or whether it is a Neumann specific extension of the process within the AES-42 Rx/Tx implementation.

@JW: As I understand it, you do not appear to be correct in stating that the clock frequency itself is not sent back to the mic; only the correction signal which is quite low rate to fit in with the signalling bandwidth of the reverse connection.
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Old 3rd May 2014 | Show parent
  #43
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Quote:
Originally Posted by panatrope View Post
@JW: As I understand it, you do not appear to be correct in stating that the clock frequency itself is not sent back to the mic; only the correction signal which is quite low rate to fit in with the signalling bandwidth of the reverse connection.
What I wrote in my paper is correct - I ran it by Neumann, Schoeps and Sennheiser as I finalised the text and they all gave it the OK.
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Old 5th May 2014
  #44
Gear Head
Is AES 32 a good option for those who want mix 4 analog microphones in two stereo tracks?
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Old 5th May 2014 | Show parent
  #45
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No it is not a good option. I think you mean AES 42. AES 42 requires digital microphones.
To mix your 4 mics, use an analog console.
Go in line in on the Nig nog. (This is factory speak for Nagra--this is what they call it at the factory.)
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Old 5th May 2014
  #46
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Plush's Avatar
Nagra Seven has landed.
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Old 6th May 2014 | Show parent
  #47
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Let the games begin!
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Old 6th May 2014 | Show parent
  #48
Gear Head
Quote:
Originally Posted by Plush View Post
No it is not a good option. I think you mean AES 42. AES 42 requires digital microphones.
To mix your 4 mics, use an analog console.
Go in line in on the Nig nog. (This is factory speak for Nagra--this is what they call it at the factory.)
thank you Plush
I mean mix aes 32 stereo signal from my mytek 176 ADC into the N 7 with two other analog micros in the N7. Is it a good idea?
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Old 6th May 2014 | Show parent
  #49
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Question

Quote:
Originally Posted by FREITOJOS View Post
thank you Plush
I mean mix aes 32 stereo signal from my mytek 176 ADC into the N 7 with two other analog micros in the N7. Is it a good idea?
I thought that an AES standard input (as is on the NAGRA seven) was AES3, not AES32
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Old 6th May 2014 | Show parent
  #50
Gear Head
Quote:
Originally Posted by John Willett View Post
I thought that an AES standard input (as is on the NAGRA seven) was AES3, not AES32
I am sory,
Yes AES/EBU OR AES3 .
Is it a good idea mix the two mics via mytek with two mics in the Nagra?
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Old 6th May 2014 | Show parent
  #51
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Smile

Quote:
Originally Posted by FREITOJOS View Post
I am sory,
Yes AES/EBU OR AES3 .
Is it a good idea mix the two mics via mytek with two mics in the Nagra?
OK if the latency of both ADCs is the same.
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Old 6th May 2014 | Show parent
  #52
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Plush's Avatar
Quote:
Originally Posted by FREITOJOS View Post
I am sory,
Yes AES/EBU OR AES3 .
Is it a good idea mix the two mics via mytek with two mics in the Nagra?
No it is not a good idea because you do not have control over the mixing of the 4 inputs. There is no mixer in the Nagra Seven.
There are two ways to approach recording your 4 mics. Use a multi-track machine like a Nagra VI and mix later or mix to stereo on the spot using an analog console.

To use a Mytek converter in to the Nagra Seven means that Mytek clocks the recorder and then you plug your mics in to the two mic inputs. You could do this by clocking the Nagra Seven from the AES input. However, there is no word clock bnc connector provided on the basic Nagra Seven music machine.
( I guess that a word clock bnc is provided with the time code option for the Nagra Seven)

The way to approach multi-mic recording with a stereo machine is to use the traditional method of using a console to mix the program material.

I think that you must want the Nagra Seven to be something that it is not.
It is a stereo machine with two mic inputs. Viewed also in a different way, it is a reporter's recorder with provision for powering a single digital interview mic.
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Old 7th May 2014 | Show parent
  #53
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Larry Elliott's Avatar
Quote:
Originally Posted by Plush View Post
Nagra Seven has landed.
Looking forward to your report!
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Old 10th July 2014 | Show parent
  #54
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surflounge's Avatar
bump for Nagra VII report on preamp sound
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Old 10th July 2014 | Show parent
  #55
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Plush's Avatar
Preamp sound is outstanding. I have used with Schoeps, AKG, and Senn.. Very pure tone and clearly neutral with high detail.

Confirmed!--conversion is the same as in Nagra VI.

I will have a thorough report on the Nagra Seven. It is a marvelous recorder and very lightweight. Soon I will test its AES 42 capabilities with two Senn. 8020 and a Senn. 8000 digital module. It took 2 months to get a custom cable from DE.

Go Argentina!!!!!
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Old 11th July 2014 | Show parent
  #56
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Quote:
Originally Posted by Plush View Post
The way to approach multi-mic recording with a stereo machine is to use the traditional method of using a console to mix the program material.

I think that you must want the Nagra Seven to be something that it is not.
It looks like I might get my hands on an N7 shortly for show and tell. Mainly out of intellectual curiousity (and an equal amount of perversity) I may try a 4 mic recording if circumstances are appropriate. Of course it requires the services of my existing Nagra V. Two main mics in via the N7 analog, outriggers or spotters via the NV and its AES out to N7 AES in. Separate gain controls in the N7 and NV permit an on-the spot mix in the N7. (I won't consider subsequently tweaking the mix with the second pair recorded separately on the NV ....).

This could also be a useful technique for making an overdub where composite recordings need to be made. (Shades of Les Paul ...). But I agree .. not recommended standard operation procedure. An NVI might be better (and more expensive), but it also valid to use the resources you know and love. The above configuration gives me a four channel battery operate rig, without having to rely on my mains-operated UFX rig. (Or a certain multichannel black plastic shaver ... )

Of course, I do look forward to a fully configurable Mode 2 digital stereo mic to use in such circumstances. But no reason not to have a bit of adult fun in the mean time.
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Old 11th July 2014 | Show parent
  #57
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surflounge's Avatar
Quote:
Originally Posted by Plush View Post
Preamp sound is outstanding. I have used with Schoeps, AKG, and Senn.. Very pure tone and clearly neutral with high detail.
thanks for the good news
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Old 11th July 2014 | Show parent
  #58
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Wink

Quote:
Originally Posted by Plush View Post
It took 2 months to get a custom cable from DE.
It took me a week - I got the connection specs from DE and had mine made in the UK specially for me.

I hated the plug and socket in the middle of the DE one.
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Old 11th July 2014 | Show parent
  #59
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Plush's Avatar
John--you are a wizard.
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Old 11th July 2014 | Show parent
  #60
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Quote:
Originally Posted by Plush View Post
John--you are a wizard.
Thanks heh

I have just sent you an e-mail with the drawings I have.
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