From Jamie at grace..good to know(though I dont like Lunatec personally)
amie from Grace Design here. I just received an email from Jim, which drew our attention to the thread. Sorry there has been so much confusion regarding this.
The digital outputs (AES1, AES2, S/PDIF and TOSLINK) are 180 degrees out of phase. As you know absolute polarity does not have an affect on the sound when the relative polarity between the channels is consistent. It does however become an issue if you are summing multiple sources that have inverted polarities, which is the case here. With the V3 digital outputs 180 degrees out of phase from the analog inputs on the 744, the low frequency response will be compromised if these signals are summed.
The fact that the V3's digital outputs are 180 degrees out of phase was only recently discovered when both the analog and digital outs were recorded simultaneously to a workstation. Upon discovery we immediately corrected this issue in new production units. Beginning with serial number V3497, all of the digital outputs are in phase with the input. Any unit prior to this serial number will have inverted polarity on the digital outputs.
Again, when recording two channel audio this is not a problem, but for multi-channel or matrix recordings that use the digital outputs, this should be corrected. Obviously we are here for any of you who want/need to have the digital output in phase with the input and will provide this service at no charge under warranty. To arrange for this service, please contact me at jamie@gracedesign.com.
Once again our apologies for the confusion and any trouble this may have caused.
Best regards from snowy Boulder, CO
- jamie
Comments
This has appeared on a lot of places lately. My guess is that it
This has appeared on a lot of places lately. My guess is that it originated from a discussion at http://www.taperssection.com where a person used a V3 + Sound Devices 744T and originally blamed the problem at the 744.
I for sure cannot hear "absolute" phase. Maybe there are people that can.
Gunnar
Thanks for word from Stockholm! I have made many recordings and
Thanks for word from Stockholm!
I have made many recordings and have never noticed any kind of audible problem.
I should mention that Grace Design whom I have contacted have been really excellent and very open about this issue. Their continuing support for people who have brought their products is admirable (no I have no connection with Grace - just want to give credit where it due).
It really is a moot point whether it is a problem at all.
Rob
Yep - it's one of life's little mysteries. Some people are sensi
Yep - it's one of life's little mysteries. Some people are sensitive to signal polarity, others are completely insensitive to it and for some, sensitivity varies according to circumstances.
Regardless of this however, where it definitely isn't a moot point is in the specific circumstances described in the original post:
It does however become an issue if you are summing multiple sources that have inverted polarities, which is the case here. With the V3 digital outputs 180 degrees out of phase from the analog inputs on the 744, the low frequency response will be compromised if these signals are summed.
The effects of combining signals which are in opposite polarities are nothing to do with a person's sensitivity to the polarity of the individual signals. The results are pretty obvious to any listener and far from moot ;)
V3 polarity issue Thanks for putting me on to this Big Ray as I
V3 polarity issue
Thanks for putting me on to this Big Ray as I own a V3 which is in the serial number death zone mentioned in the post.
Are you able to tell me where this was originally posted? Is there a relevant thread.
My understanding from Grace is that it is a moot point whether this problem really is audible at all. I have certainly never noticed any issue. By the way, I rather like my V3. Very clean and smooth.
Rob Castiglione