Jump to content

Zaxcom and AudioLTD digital wireless - the future


RadoStefanov

Recommended Posts

This particular discussion seems to boil down to theoretical vs practical.

Debating the finer points of theory is -- as a quick look herein tells us -- quite a popular armchair sport that many of us engage in from time to time.  However, in the heat of battle on set, how something actually performs readily trumps specsmanship.

 

Link to comment
Share on other sites

55 minutes ago, Werner Althaus said:

I admire the company and think they’re on the cutting edge of technology. I’ve never had the pleasure to use one in the field myself but from all I’ve heard, read and seen their products appear to be great.

Just curious have you ever used the Audio Limited? What wireless are you currently  using?

Link to comment
Share on other sites

2 minutes ago, Jack Norflus said:

Just curious have you ever used the Audio Limited? What wireless are you currently  using?

Thanks for asking, No, I didn't have the pleasure to try them either.

Currently I use Lectro 200 and 400 series, Sennheiser evolution100, 300s, 500's, and my favs SK250's into 3000 series receiver. But for location work it's usually Lectros only.

Link to comment
Share on other sites

I will refrain from posting more in this thread unless I’m asked a direct question, sound fair?

Respectfully

Please don't. This is a discussion board which lives only through active and lively participation in a topic. Just be prepared to encounter stronger than usual opposition and be accused of an anti Zaxcom conspiracy when you just hint a critique towards Zaxcom. Oh wait a minute, that already happened.

One more thing regarding the compromises the various manufacturers chose to make: in the Zaxcom case, the important compromise in my opinion was not to trade off higher sample rate for many transmitters per TV channel, but rather long (usable) range.

Whatever the ramifications of the reduced sample rate, the results speak for themselves.

I ditched all of my bodypack Zaxcom transmitters for various reasons, but none of them was sound quality.

The only Zaxcom transmitter I use on a regular basis is the one for the boom mic, arguably the one where sound quality matters most. And it's the precise reason why I chose Zaxcom, because it sounds better than any of the others I have tried.

Anybody know if Nyquist is on this site?

Nyquist died in 1976

Link to comment
Share on other sites

Proper blind real world tests you'd never be able to discern the difference between 32K and 48K, because as Philip eloquently pointed out, there's a number of much more important factors at work.

Bet blind tests would also expose the supposed warmth of one over another is a figment in the head of the listener.

On the other hand, if you had a recording and applied such a low pass filter that all frequencies would be cut off at 16kHz, you'd definetely hear the difference. Come to think of it, I believe most of us would hear the difference between 32 and 48k sampling rate. Whether or not it matters in real life is a different question, though.

Link to comment
Share on other sites

"One more thing regarding the compromises the various manufacturers chose to make: in the Zaxcom case, the important compromise in my opinion was not to trade off higher sample rate for many transmitters per TV channel, but rather long (usable) range."

Please correct me if I am wrong on this but I thought all zaxcom wireless involves a 32khz SR somewhere in the chain (as opposed to just the ZHD system for the sake of range, density or otherwise).

 

Link to comment
Share on other sites

.

Nyquist died in 1976

And what about Shannon?  He always gets left out of the Nyquist-Shannon Sampling theorem ... (and died in 2001)

True, but Jeff didn't ask about Shannon...

"Please correct me if I am wrong on this but I thought all zaxcom wireless involves a 32khz SR somewhere in the chain (as opposed to just the ZHD system for the sake of range, density or otherwise).

 

I believe that's true, but it may well have always been a compromise like that. I don't know the design decisions Zaxcom took, but I do know that for me, range over density is the important compromise - and I'm guessing size is another compromise. The ability to squeeze 60 wireless channels into one TV channel is all but irrelevant to me

Link to comment
Share on other sites

Okay, just one more comment in reply to one of your comments: "What would you say if I claimed that SFXs recorded on a Zoom set to mp3 format were  “true 24-bit 48K industry standard broadcast wave files” just because I plugged the Zoom’s analog output into my recorder set to those specs and hit record? That'd be a numbers game IMO" This is a flawed analogy: the recording on the Zoom recorder would be an mp3 recording, no doubt about that. If your input to the Zoom was routed as well to another recorder set at 24-bit - 48K, then those SFXs would be at 24-bit - 48K. If you were RE-recording or copying the original Zoom mp3 file, it would be a deception to claim that these were SFXs recorded at 24-bit - 48K. My comment about my files being true 24-bit - 48K was referencing your caution that people in post are going to be upset and are going to have to jump through hurdles because I'm turning in files that are not 48K. It is no different than when I turn in a file to post for use in a scene where the sound is from an old Victrola playing back a 78 rpm record --- my file will be a faithful and honest industry standard file. Regarding my recording of the output of my wireless receiver, the file will be 24-bit - 48K based on sound being transmitted from the  transmitter with a frequency response of 20 to 16K. So, we are back to the all important LISTENING test. Is there a significant audio quality difference for our purposes between 20 to 16K and 20 to 20K?

Link to comment
Share on other sites

Is there a significant audio quality difference for our purposes between 20 to 16K and 20 to 20K?

I think the point Werner is mostly trying to make is that it won't be 20-16k, but rather 20-12k, due to the filters in use, much like it would be 20-maybe 22k in 48k recordings

Still, listening would of course be the best test

Link to comment
Share on other sites

Constantin said: “Just be prepared to encounter stronger than usual opposition and be accused of an anti Zaxcom conspiracy when you just hint a critique towards Zaxcom. Oh wait a minute, that already happened.”

 

I guess I walked right into that one, LOL

 

 

Jeff said: “….Regarding my recording of the output of my wireless receiver, the file will be 24-bit - 48K based on sound being transmitted from the  transmitter with a frequency response of 20 to 16K. So, we are back to the all important LISTENING test. Is there a significant audio quality difference for our purposes between 20 to 16K and 20 to 20K?”

 

 

Assuming that you used a lav with a frequency response of up to 20KHz I’d stand by my statement that the RF system doesn’t deliver the full response of the mic due to the SR but you’re right, you did faithfully capture the analog output at 48/24, I think we can agree on that. As a post mixer I might be wondering why that mic captured at 48/24 cuts off drastically at 15KHz but I wouldn’t loose sleep over it either.

 

Does it matter? Depends on the type work you do. I do everything from OB, mixing live regional sports where fidelity isn’t much of a concern (those wireless parabs or other sideline wireless mics would be fine with TXs at 22KHz or less ) to music recording of all genres and of course loads of EFP.

When I record and mix English language Opera where diction is all important ( no subtitles in the final program) I tend to use my DPA miniature mics on the principals to blend with the 5 to 8 Schoeps Supercardiods spread across the stage. This helps the audience to understand the lyrics to a greater degree.

 I would want the response of those DPA mics to be as good as a cabled connection both in terms of frequency response as well as dynamic range because I might have to rely on them exclusively should there be too much external noise from coughing audience members or footsteps or whatever, etc. been there, done that. So yes, I dare to say that it matters under certain circumstances.

But let me again say that I agree with listening tests superseding any theoretical discussion.

Thanks.

Link to comment
Share on other sites

what about post? Does 32 gives them enough room to play with before hitting a ceiling? If I take a photo with my mirror less camera on medium and high jpg, it looks the same. But if I try to do some fiddling in Photoshop I obviously have a bit more room with the higher jpg setting. Doesn't it work the same with kHz thus there is still an use for 96khz in music production, though it will master to 41 or 48 anyways. Just wonder what 32 gives in that respect. 

Link to comment
Share on other sites

Gah...

Whenever I have mixed a movie in post, I've never ever ever ever heard the lack of 16khz and above. On big deal movies, they are still using SFX from Sound Ideas that are probably not even CD quality, and noone cared. The Wilhelm scream is not 48k in its original recording, and no one cares.

Listen to a Zaxcom system. Use a Zaxcom system, then ask yourself if you can actually hear the difference between that and any other system, and hot answer will probably be "Yes, I can hear the difference. It sounds awesome". Cause it does.

Not claiming Zaxcom is superior, just claiming that you ears are the only measurement tool you should use for real, because that's where the secret ingredient to the sauce that is your mixing and delivery lies. Read the numbers and specs all you want.

Heck, I even think battery life, usability, connectivity, size, range trumps how it sounds to begin with. Sound is often so good in all wireless systems the it's often not even an issue anymore for any real type of work. If you're working on measuring sound quality and sample rates then I guess it matters..

Link to comment
Share on other sites

Human hearing range 20 to 20 kHz ..  It sounds so nice 20 to 20...

Do we remember which study says that ? Who has studied that ?

I don't know who first came up with this, but it's relatively easy to test someone's hearing, frequency span and sensitivity (dB). Any ear doctor can test your hearing and determine your own frequency span. Of course, this changes with age with babies apparently having the best hearing (once their brain has started to accept signals from the ear). The older we get the worse our hering gets and it's the high frequencies we lose first. My parents (in their 70's) haven't been able to hear that high pitched tone when we still had an old TV for the past 15 years, I'd say.

Link to comment
Share on other sites

2 hours ago, Ken Wilkinson said:

When I do audio post, I always roll off the dialogue around 12k, sometimes lower.

5ms = about a quarter frame of latency.

I would call both of these non-issues.

isnt 5ms in fact about 1/8th of a frame - dependent on your frame rate, of course ;-)

so that makes 2ms about 1/20th of a frame (at 25fps),

and 18ms is nearly half a frame (at 25fps) !!!

 

Kindest, sb

Link to comment
Share on other sites

1 hour ago, Bash said:

isnt 5ms in fact about 1/8th of a frame - dependent on your frame rate, of course ;-)

so that makes 2ms about 1/20th of a frame (at 25fps),

and 18ms is nearly half a frame (at 25fps) !!!

 

Kindest, sb

Yes, yes, yes negligible .... :)

Link to comment
Share on other sites

6 hours ago, Ken Wilkinson said:

When I do audio post, I always roll off the dialogue around 12k, sometimes lower.

5ms = about a quarter frame of latency.

I would call both of these non-issues.

Straw man? No 1 has claimed 5ms (if that's what it is) to be significant for lip sync, which is the inference when measuring latency to fractions of a frame, however 5ms may be significant when when mixing different sources on equipment where an input delay cannot be applied Eg: Sound Devices 302, 442, 552, SQNs, Sonosax SX-32 etc etc. I know this a non-issue if you are using a modern recorder but lots of work is still done with just a mixer to camera. Just saying.

Link to comment
Share on other sites

8 hours ago, Constantin said:

I don't know who first came up with this, but it's relatively easy to test someone's hearing, frequency span and sensitivity (dB). Any ear doctor can test your hearing and determine your own frequency span. Of course, this changes with age with babies apparently having the best hearing (once their brain has started to accept signals from the ear). The older we get the worse our hering gets and it's the high frequencies we lose first. My parents (in their 70's) haven't been able to hear that high pitched tone when we still had an old TV for the past 15 years, I'd say.

Constantin, I'd like to comment on that assessment but not before mentioning that I am not in favor of ultrahigh SRs like 192 or even 96KHz. yes it sounds different than 48 but not for the reasons proponents imagine, quite the contrary, it usually sounds worse. I'm saying this so you know that I'm not coming at this from some esoteric audiophile POV. The discussions about SRs at the dawn of digital mostly hinted at an optimum SR in 60 to 70KHz range but for practical reasons lower SRs were chosen.

Now back to the hearing test: I think that going to an audiologist will tell you something about your hearing threshold at various frequencies but it doesn't tell the whole story. How do you think Bob Clearmountain or Bruce Swedien were able to mix great sounding records when their age would indicate an upper limit of 10K tops? Many top mixers are technically too old to hear "up there" but good luck trying to trick them by cutting off significantly below 20K. It's a feel thing and mixers learn to adjust to  their diminishing hearing capabilities. Otherwise they couldn't do their jobs, something that George Martin understood when he really felt that it was no longer possible for him to do his work he enlisted help. I know this is outside of the realm of what this forum is about but  so forgive the sidetrack.

 

Link to comment
Share on other sites

8 hours ago, Ken Wilkinson said:

When I do audio post, I always roll off the dialogue around 12k, sometimes lower.

5ms = about a quarter frame of latency.

I would call both of these non-issues.

At at 12dB per octave slope, 3db down at 12K you still have the potential of content >15 or 16KHz to come through unlike the 32KHz SR scenario. An 18dB/octave slope at 17KHz is about where it becomes noticeable to me, depending on the voices and situation, mind you that I choose to roll-off not because there's nothing up there, quite the contrary, I find that it cleans things up. But if the track was recorded dual system with a good recorder/ mixer  and w/o RFI  I usually leave the LPF off.  Maybe I imagine that it's better because I know it's full bandwidth, who knows. I'm certainly not immune to expectation bias. But knowing it's there if I need it puts me at ease. YMMV. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...