Sound Devices 664

[Jeff Wexler]

Again, there are TWO different but related issues (and I don't really mean issues, technical subjects might be a better term) being discussed. One is the issue of mixing two or more sources which are not "in time" when they arrive at the input of your mixer or recorder or mixer-recorder. This would be when you are mixing an analog boom mic for example with a wireless receiver with a latency factor. There are two "solutions" to this: one is that it is NOT a problem (sound mixers have reported that they do this all the time, regardless of the mixer or recording device they are using, and they just deal with it), two, it is a problem that can be solved by having delay processing available on the input device (mixer, recorder, etc.) to delay the boom mic signal with respect to the wireless signal.

The next issue, and this is where the 664 comes properly into the discussion, is the time and phase alignment (or lack of) from inputs to OUTPUTS. Because of the architecture of the inputs and outputs on the 664, as I understand it (and I'm the first to admit I do not fully understand it all) compared to all digital mixing and throughput of Nomad, there is a concern that if you used all 4 outputs of the 664 to feed the 4 inputs of a camera, for example, these 4 tracks (on the external device) could have time and phase problems in relation to each other. I think this issue has been resolved and properly explained, but I'm not sure. It should not be confused with Subject No. 1 which could be a factor in one's mixing style with any combination of devices.

[BAB414]

Got it Jeff, thank you.

[PTA]

I think this issue has been resolved and properly explained, but I'm not sure.

I thought this was resolved. What are you not sure about? Did I miss something?

[studiomprd]

" Did I miss something? "

I thought I read someplace recently that their is still a problem, perhaps it is a rumor about digital mic's ??

[Matt Bacon AMPS]

I thought I read someplace recently that there is still a problem, perhaps it is a rumor about digital mic's ??

May I suggest you consult the HAT rather than spreading rumours...

[Solid Goldberger]

Are so many of you using digital microphones that this is a legit concern?

I've yet to meet any Doc/Reality mixers that are using a SuperCMIT, and while i'm sure there are several out there, clearly this is less of a market then this thread is making it out to be.

I have to say I'm out of the running for a 664, because of the lack of digital delay. I know this has been discussed, and Glen T says above, people with digital wireless systems deal with it every day, but I found it almost imposssible to mix a documentary with Zaxcom wireless and an analog boom, on an analog mixer. Your presenter or main contributer (maybe two) will either be being boomed or on radios, but then if they start talking to someone else and you need to boom that new character and keep the radios up for the others, there is a nasty delay, that can't be rectified without dialing in some digital delay on the boom. Mixing fiction is a different matter, most importantly you have two hands to mix, and you generally know who is going to speak next.

Some people with digital wireless may be able to cope with it, with one hand, but not me unfortunately. I do think SD have come up with a fantastic product though, it's just not for me.

For those using Zax wireless, I'm not sure why you wouldn't just go through the analog outputs into this analog-based mixer (though I'm also not sure why you'd consider the 664 in this head-to-head, as you'd be losing the Zaxnet advantage of your wireless). My understanding is the delay on both Lectro and Zax wireless is 3(ish) milliseconds. Also, in the above scenario, wouldn't a simple flip of a phase reverse switch do a similar job as a digital delay, or am I missing something?

e.

[VASI]

I don't know why some people confused about analog or digital sound.

analog-to-digital

digital-to-analog

[studiomprd]

" wouldn't a simple flip of a phase reverse switch do a similar job as a digital delay, or am I missing something? "

no, yes.

[PTA]

" Did I miss something? "

I thought I read someplace recently that their is still a problem, perhaps it is a rumor about digital mic's ??

You should let it go, or are you starting a rumor?

[Jeff Wexler]

My understanding is the delay on both Lectro and Zax wireless is 3(ish) milliseconds. Also, in the above scenario, wouldn't a simple flip of a phase reverse switch do a similar job as a digital delay, or am I missing something?

e.

Yes, you are missing something big time. The phase issues we are talking about are not the 180 degree phase difference that can happen because of different wiring in the microphone or input source.

You are not missing anything when you ask if there are a lot of people using digital microphones --- there are nota lot of people using digital microphones, this is true, but the timing and phase issue(s) (here we go again) refer to potential problems mixing analog microphones, analog hybrid wireless (with delay) and digital wireless (with delay).

[LarryF]

[snip]

Also, in the above scenario, wouldn't a simple flip of a phase reverse switch do a similar job as a digital delay, or am I missing something?

e.

Try this as a thought experiment. Delay an audio signal by three hours. You won't hear the beginning of the sound stream for three hours. On the same audio stream, flip the phase. You still hear it instantly. They are not the same thing.

If you delay a signal by 0.5ms, and mix it with the same undelayed signal you will get a phase cancellation at 1 kHz, 2 kHz, 3 kHz, and so forth with boosts at 1.5 kHz, 2.5 kHz, 3.5 kHz and so forth. This is comb filtering. If you flip the phase and mix that with the same unflipped signal, you will get cancellation at all frequencies. So again, delay and phase reversal are very different things.

Best,

Larry F

Lectro

[Solid Goldberger]

Yes, you are missing something big time. The phase issues we are talking about are not the 180 degree phase difference that can happen because of different wiring in the microphone or input source.

You are not missing anything when you ask if there are a lot of people using digital microphones --- there are nota lot of people using digital microphones, this is true, but the timing and phase issue(s) (here we go again) refer to potential problems mixing analog microphones, analog hybrid wireless (with delay) and digital wireless (with delay).

Right, I understand this, but in the example of Digital Wireless with Analog Boom, how severe of a delay are we talking about between these signals on a system such as the 664? I've not read any hard numbers, though they could be there and I've missed them. I'm not being argumentative, I'd genuinely like to understand the problem more.

Are we talking about more then a couple of milliseconds? If not, its hard for me to believe that in a documentary situation, someone can dial the delay in with one hand while [consistently] booming from a uniform distance with one hand, on the fly, compensating as you go for differences in digital delay and microphone distance. In an unscripted situation, this is what all those fancy ISOs (and their accompanying post department) are for.

But again, I would really like someone to explain this if I'm not understanding correctly.

e.

P.S. They said (earlier in this thread) that they might add this input delay, which i am taking to mean probably (based on all the bickering), so all this arguing might be moot.

[Solid Goldberger]

Try this as a thought experiment. Delay an audio signal by three hours. You won't hear the beginning of the sound stream for three hours. On the same audio stream, flip the phase. You still hear it instantly. They are not the same thing.

If you delay a signal by 0.5ms, and mix it with the same undelayed signal you will get a phase cancellation at 1 kHz, 2 kHz, 3 kHz, and so forth with boosts at 1.5 kHz, 2.5 kHz, 3.5 kHz and so forth. This is comb filtering. If you flip the phase and mix that with the same unflipped signal, you will get cancellation at all frequencies. So again, delay and phase reversal are very different things.

Best,

Larry F

Lectro

I stand corrected re: phase reverse. Its not something I do very often so I was just speculating.

My question in regards to actual usage in the field from my previous comment (#663) still applies though. How much delay are we talking about? Is this a real thing that could (or should) be done in an unscripted scenario? Hope i'm not revealing too much ignorance here. I just do this kind of work every day and have never received any feedback from a post dept. about the timing my digital hybrid wireless and analog boom mics being mis-aligned.

e.

[Shastapete]

I stand corrected re: phase reverse. Its not something I do very often so I was just speculating.

My question in regards to actual usage in the field from my previous comment (#663) still applies though. How much delay are we talking about? Is this a real thing that could (or should) be done in an unscripted scenario? Hope i'm not revealing too much ignorance here. I just do this kind of work every day and have never received any feedback from a post dept. about the timing my digital hybrid wireless and analog boom mics being mis-aligned.

e.

It depends... (sorry)

As others have mentioned above, if you think it is a problem, it is a problem, if you don't… well, you don't. There are a bunch of things in play that can affect the perception of delay between two sources

Digital Processing (re: Zax and Lecro lavs)

Intensity of the sound

Frequencies (ie what frequencies are coming in to the mic at the angle it is presented to our noise maker)

Distance to the noise maker

Mix level

any combination of the above can change the perception of the delay. That 3ms delay of the Lav mic could be masked if your boom is roughly 3 feet away from your talent. Also, the effect of 3ms of delay will be perceived as phasing or comb filtering (see Larry's comment above).

In practical use, for me, I never really have an issue. As in my unscripted situations I'm usually booming too, and if it doesn't sound good I move the mic until it does

[Jeff Wexler]

My question in regards to actual usage in the field from my previous comment (#663) still applies though. How much delay are we talking about? Is this a real thing that could (or should) be done in an unscripted scenario? Hope i'm not revealing too much ignorance here. I just do this kind of work every day and have never received any feedback from a post dept. about the timing my digital hybrid wireless and analog boom mics being mis-aligned.

e.

The typical nominal delay from digital and digital hybrid wireless systems is approx. 3 ms. The delay from an analog microphone plugged directly into the input is ZERO, there is no delay. When mixing these two sources on ANY mixing device, this delay CAN present itself as some sort of mixing challenge. This will be the case with ANY and ALL mixing devices, not just the 664 or Nomad, or whatever. In the real world we have two schools of thought on this "problem": those that say it is a real problem and they really can't mix these two sources without some method of delaying the analog boom mic, and then there are those who say it is NOT a problem, they do it everyday without feeling any need for any delay compensation. So, you have to answer for YOURSELF whether you need to be able to delay an input where your boom mic is plugged in when mixing it with your wireless (Lectro Hybrid or Zaxcom Digital) --- it's as simple as that. If you feel you DO need to have this delay function then you need to know whether the device you want to use (Nomad, SD 664, Tascam HP-2, SD 302, whatever) can do this or not.

[Jesper Magnusson]

Ok, I just finished reading through this whole thread, and first of all I want to thank everyone that have been clearing out all the questions regarding this seemingly fantastic new product - especially the employees from Sound Devices.

One thing though that I was very excited about when reading the specs, only seemed to raise a single mention on the whole thread, and that is the temperature specs. It seems that besides the cantar, this is the second mixer/recorder that is actually built to handle sub-zero temperatures (celsius). This alone makes it a viable option for places with harsh winters. I would be very interested to know what changes has been made to bring about that compared to the other products in the SD range?

[studiomprd]

" It depends... (sorry) "

why ?

" revealing too much ignorance here. "

you probably should knock $50 off your daily rate...

" it's as simple as that. "

well, maybe...

because typically a wireless lav mic is closer to the sound sourve than an analog boom mic, thus reducing the ~3ms delay...

OTOH, Jeff is pretty much correct that it is mostly a problem, only if you want it to be, and I suspect some folks are fueling this little brush fire with agenda's...

" what changes has been made to bring about "

probably lots of little things like components selection ...

bottom line: its newer, its better...

[Chris Campion]

Is the option be available to route any camera returns A, B or C to an Aux bus X1 or X2? For the purpose of routing camera (or video village) playback audio out to cans from the X1/2 outs?

I figure the Aux outs would be the best way for a client feed, similar to how I use the 'output 1' on 744t now. The difference being that with my 442/744 I can provide return-feed playback over cans by swapping the jack into the extra Headphone out on the mixer. I'm just trying to work out how to do it with a 664. Maybe a small external DIY switch is the answer.

[RScottATL]

How much delay are we talking about? Is this a real thing that could (or should) be done in an unscripted scenario? Hope i'm not revealing too much ignorance here. I just do this kind of work every day and have never received any feedback from a post dept. about the timing my digital hybrid wireless and analog boom mics being mis-aligned.

e.

I'd just compensate the analog signals (hardwired boom) by the delay of the digital systems (lectro hybrid systems). In my case, 3.2ms. I would not bother much to compensate for physical differences or even attempt to change this on the fly... or ever.

When the two microphones are focussed at the same talent and are mixed, if there is no compensation, the resulting sound will be hollow sounding, somewhat as if standing right next to a hard wall. If the boom is flying over talent further away, I don't perceive a big difference. The problem is only a huge deal if your final mix is what is going to air and you cannot tolerate this type of coloration.

In most cases, ISO tracks mean we don't use the production mix and other means (putting a plug transmitter on the boom) can also fix the problem. If you must never accept this phasing issue and cannot deal with it in another manner, then the Nomad and 788 are great digital recorders that provide the featureset you require.

As always, many great product choices makes it a good time to be shopping for a recorder. Pick the one that suits you and go make a living.

[Peter Mega]

Is the option be available to route any camera returns A, B or C to an Aux bus X1 or X2? For the purpose of routing camera (or video village) playback audio out to cans from the X1/2 outs?

I figure the Aux outs would be the best way for a client feed, similar to how I use the 'output 1' on 744t now. The difference being that with my 442/744 I can provide return-feed playback over cans by swapping the jack into the extra Headphone out on the mixer. I'm just trying to work out how to do it with a 664. Maybe a small external DIY switch is the answer.

This seems over complicated. Simply route whatever you want to the aux out and send it.

This way your not relying on the camera in any way, especially if your sending wireless to camera (with no return).

On another note, many posts ago in this thread I talked about not letting production use the 12 input, 16 track awesome machine to make us even more of a pack mule than we already are. Someone replied about renting wireless to productions etc etc.

I don't have a problem with anyone renting wireless to production. I do it all the time. What we can't do is agree to carry 12 rx in a bag and tell production we can do it all. 12 or more wireless is a job for at least 3 to 4 guys/gals.

By all means rent out your gear, no problem.

Cheers

Peter Mega

[Matt Mayer]

Is the option be available to route any camera returns A, B or C to an Aux bus X1 or X2? For the purpose of routing camera (or video village) playback audio out to cans from the X1/2 outs?

I figure the Aux outs would be the best way for a client feed, similar to how I use the 'output 1' on 744t now. The difference being that with my 442/744 I can provide return-feed playback over cans by swapping the jack into the extra Headphone out on the mixer. I'm just trying to work out how to do it with a 664. Maybe a small external DIY switch is the answer.

There is no option to route the Returns to X1 or X2.

You can, however, select L/R or Ret A/B/C to route out the Tape Output. You would have to change the routing of the tape output in the menus if you wanted to change over from L/R to a Return.

[ProSound]

There is no need for any delay on inputs. I'd never mix to mics that are on same talent

[Chris Campion]

There is no option to route the Returns to X1 or X2.

You can, however, select L/R or Ret A/B/C to route out the Tape Output. You would have to change the routing of the tape output in the menus if you wanted to change over from L/R to a Return.

I see Matt, thanks, thats good news.. I plan to use the Aux1 as purely an IEM mix (and not record it) and I can make up a switch to flick IEM's to Tape out instead, when camera wants to play something back.

[Matt Mayer]

I see Matt, thanks, thats good news.. I plan to use the Aux1 as purely an IEM mix (and not record it) and I can make up a switch to flick IEM's to Tape out instead, when camera wants to play something back.

In that case, make sure and set X1 to a -10 Tape Level output and trim your TX to match that level. That way there will be no level change when you flip over to the Tape Out.

[drpro]

Matt what CF/SD cards are recommended? Will the 664 support UMDA 7 cards?

Thanks

David