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Zaxcom notch filters on rushes?

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Hey all Zaxcom users out there, had a very odd thing come up with some rushes from a recent shoot, that being when put under the post microscope most tracks (mix & Iso) had what appears to be notch filters at 2,4 & 6k (see attached pic).

 

I use full Zax setup incl Fusion/mix12/zax wireless boom and body packs etc, have done for a while and have not had this issue before.

 

I am at a loss to where these came from, I don't use any eq in the field, def had all the notch filters turned off etc. I have used the 2k filters in the TRX's to stop any possible zaxnet interference but what about the 4 & 6k etc?

 

And while I'm here, what are zax users thoughts on the 2k trx filter, use it / not use it / etc. If it is the issue here I'm def switching them all off.

 

Regards & thanks,

Chris.

 

 

068E:5.A1_Mix.png

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I had reports from post on a job I did. They used another production mixer in another country for that portion of the job, and reported they had seen huge notch filtering in the files. I contacted the mixer, and he reported as you have that they were all off. No explanation as to why there were these filters applied.

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Did a few test records and visited post, the issue is as expected, it's the 2k notch filter on the TRX's that does it, unbeknown to me it also puts notch filters in at 4 & 6k. I think in the past I never used the 2k filter but for some reason selected it on last shoot. In reality you can't hear any difference with it switched in or out and I had it in as a precaution, would just be nice to know about the it also being at 4&6k before hearing about it post shoot. Always learning, which is good!

 

C.

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There are some things you can't hear, like SD633, 4 sample gaps between supposedly sample accurate contiguous file joins at 2GB etc.

But like you say good to know about these things, and somewhat puzzling.

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It appears to be notching at the 2k target frequency and harmonics, up to 12k, as shown in the RX screen capture. 

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1 hour ago, ronmac said:

It appears to be notching at the 2k target frequency and harmonics, up to 12k, as shown in the RX screen capture. 

 

Sounds logical to me.

 

What doesn't sound logical is applying the old "Why did you climb Mt. Everest?" axiom to adding filters into an audio path.

(You know, the old:  Q: "Why did you climb Mt. Everest?"  A: "Because it's there.")

 

"Because it's there." is not a good reason to add an audio filter.  The only proper reason is, "Because it's needed."

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I am not a fan of "fix it in post", but this may be a time to apply an exception and do the surgery in RX, when required.

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DPA4063 is recommended for use with Zaxcom but still catching RFI if the cable is in close with the TRX like in a pocket.

 

If you leave it to post your mix track will suffer. If one applies it in the TRX your radiomic will show it under the microscope. 

 

Choices ...

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54 minutes ago, Matthias Richter said:

DPA4063 is recommended for use with Zaxcom but still catching RFI if the cable is in close with the TRX like in a pocket.

 

If you leave it to post your mix track will suffer. If one applies it in the TRX your radiomic will show it under the microscope. 

 

Choices ...

 

You should not be experiencing this.  DPA had a run of 4063s a few years ago that exhibited this, but it was addressed.

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On 1/29/2018 at 12:56 PM, ronmac said:

It appears to be notching at the 2k target frequency and harmonics, up to 12k, as shown in the RX screen capture. 

Ron, That is what I was seeing too.

 

Thank you, Martin

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