borjam

Maybe that's why Apple are dragging their feet on the Mac Pro. They are planning a Maq Pro That said it's not the first time someone makes a questionable announcement of a quantum computer. D-Wave have done it several times.

Playing devil's advocate here, it's a tricky issue. What if a user, no matter how much it violates the philosophy of a field recorder, uses the computer to set up the sample rate? I've seen weirder, trust me! Coming from a security background I find it much more convenient to prevent mishaps by restricting the functionality to what you need. The designers provide two different menu options in order to determine exactly what you want to do when you connect it to a computer. - You may want to use the computer only for power. In that case, file transfer is off and USB-C mode is "power only". - You want to transfer files? USB-C mode in "power only" and activating the file transfer. - You want to use it as an audio interface? Then set USB-C mode as "Audio". It will become a class compliant USB audio device. There is a good principle in software design, albeit sadly it's being forgotten nowadays: The Principle Of Least Astonishment. Having the recorder somewhat "decide" to switch sample rates is (in my opinion) a bad choice because it's a POLA violation. Moreover, it may cause a conflict with some use cases or, who knows, future features. Given that I make a living working on computer and network security I am going to give you some free advice. Never connect a USB device to a potentially untrusted USB port unless you are certain that the device will survive unexpected USB commands. As a silly example, maybe you are in the field, you connect your recorder to a friend's laptop with who knows what audio configuration settings and you are busted Maybe SD should rename the USB-C menu to "safe sex" to make it clearer!

There is a setting to determine wether the USB port is used only for power or for audio as well. If you use it for audio it will obey a request from the computer to switch the sample rate. System->USB-C By default it’s set to “Audio”. Try setting it to “Power Only”. After you do that it won’t appear as an audio interface when connected to the computer.

Odd anyway. Did someone forget a curly brace assuming they develop in C or C++?

I reported a possibly related bug that affected 2.21. When unlinking two linked channels (on my MixPre 3, channels 1 and 2) channel 2 had some odd gain offset if the fader was at 12 o’clock (when linking them it becomes a “balance” control for the linked channels). It happened with the gain in basic mode and the rest of the unit in Advanced mode. And I found out that it was enough to switch the input source to correct it. The symptom was of course hiss due to increased gain. These little units are complex beasts. The preamps have obviously some degree of digital control, at the very least for gain, HPF, limitar, etc. Maybe some bug is leaving the control signals in a bad state which can lead to the electronics to be misconfigured or it simply adds an incorrect and excessive amount of gain. I don’t know what’s inside the more traditional SD products but I guess this is a new platform designed from scratch. Maybe by a new team? I dare to say an ambitious development. Not a relief for someone suffering the bugs of course.

The root cause is the sad state of the software industry. It’s 2018 and a “file system” perpetrated in the early 80’s for floppy disks with capacities measured in the KBs is the only common ground among the different operating systems. A new, proper FS should be designed for this kind of applications, but the audio equipment manufacturers cannot do it alone. For it to succeed the operating systems should support it as a tier-1 file system, not requiring additional downloads. Keep dreaming!

Who knows. Preroll is important for field recording applications such as nature, effects gathering, etc. And I think it's considered a given. My two previous recorders (Marantz PMD661mkii and Fostex FR-2LE) have it. Yes, I think there was some marketing oversight when they implemented polarity reversal on the MixPre 6 and 10. It's free to do with the SoC they are using if you implement it with the FPGA. But preroll can be a bit more tricky. Anyway I would dare to say that they are changing the focus from a purely marketing perspective "let's restrict this feature so that customers buy the next model" towards a "let's add this feature if the hardware can support it". That purely marketing decision is what I called "offensive" some time ago with no offense intended of course Although in the traditional Sound Devices universe the MixPres are a dime a dozen (not criticizing the prices of the traditional units at all, I know you are purchasing so much more than some iron and silicon) the MixPres have entered a market where prices are generally much lower. Of course, I imagine that Sound Devices will be able and willing to service a MixPre in 5 years. I wonder about other manufacturers competing in the same segment. Probably the rest will be churning new models almost yearly.

A good companion to you excellent book is "Mastering Audio, the Art and the Science" by Bob Katz and not only for people working on post. Except for a murky explanation of clock jitter and Internet file transfer in the first edition, concepts such as dynamics processing, digital audio, gain staging, etc, are very well explained. And I liked the K-system for example.

I've just installed it I can confirm they have fixed a bug I reported (crazy channel gain in basic mode when unlinking channels 1 and 2 on the MixPre 3). There is also preroll (on the MixPre 3, 2 seconds at 96 KHz, 5 at 44.1 KHz) and, big thank you, they listened and added phase reverse to the MixPre 3 inputs. Some more changes, so far sounds great

Of course, and my apologies for the poor explanation. In the 16 bit world every bit was sacred In the 24 bit world with dithering you can sacrifice several for headroom without bad consequences. You are right, as I said my post was written too quickly. Quantization noise is deceiving because it is not a “constant” noise signal, but it’s correlated to the recorded signal, the weaker the signal the worse. In my experience anyway (recording live jazz concerts mostly) I can leave a headroom of even 20 dB when recording drums. 20 dB related to the level when I ask the drummer to play loud during the sound check. Of course I know that during the actual concert it will be much louder.

The 5 GHz band has some advantages however. It has much more usable bandwidth and obstacles attenuate it, so distant interference should be weaker than with 2.4 GHz. Also, there is some hope as regular WiFi users move up to 5 GHz due to increased bandwidth needs. For example, here in Spain fiber optic access with speeds in excess of 100 Mbps are commonplace now. Are you going to use a 2.4 GHz network which cannot give you more than 20 Mbps of real file transfer throughput and subject to neihgbor interference? Sooner or later household applications will have to move up especially in densely populated areas. The real solution would be the 60 GHz band but it would require an access point inside each room. Gosh I remember when my 2.4 GHz network was the only one in several Km around and the noise levels were really low.

The problem is, the knobs are not motorized. There would be a disagreement. Unless they did something like controlling preamp gain with one source and mix fader with the other one.

It depends on the meter ballistics actually. A PPM will give you the maximum values, so it would be safe to align them almost with -0 dBFS. However you must take the dynamics into account. If the program level increases and you are not using limiters you will have an overload. Or, even with limiters, you might hit them too hard. With 24 bit recording systems there's no need to run everything so tight. With 16 bits its was undesirable to record at somewhat lower levels because soft signals were subject to quantization noise. Remember that the number of bits determines the resolution. At 24 bits it's safe to leave a big headroom, you will still have plenty of usable resolution. Leaving 8 bits of headroom at 24 bit will still give you full resolution 16 bit signals. Of course you can't enjoy that luxury recording at 16 bits, you would have only 8 bits which would really suck. As a rough guide you can check this table of S/N ratios for different bit depths. https://en.wikipedia.org/wiki/Audio_bit_depth

Now, seriously. Is it me or women are much better represented in the sound department than in the camera dept? Just curious.

Sound Devices: 30% discount on the music plugin for the MixPres.

It still doesn't mach the infamous "Della" campaign by Dell. Do you remember? https://www.theregister.co.uk/2009/05/12/dell_launches_della/

I have a couple of MAUI 28 at the club and I'm really happy with them. Amazing value for money. Compared to Mackie SRM-450 (we used them before, now they are useful as monitors) it's an entirely different league.

Thank you My initial skepticism about using the 2.4 GHz band has been dilluted to almost homeopathic levels now. And what I said about causing problems, I see I am most likely wrong. Maybe an obessive network administrator continuously running speed tests might notice some competition for the spectrum, but now I doubt it!

Not trying to smear anyone, sorry in case it sounds like that. But I can't avoid being very curious about the gory details. After all I am a radio geek as well and a reliable wireless microphone on the crowded 2.4 GHz band is a real achievement! Let me try to explain. Andrew Jones said: So, it seems that the Deity system can generate those hints to tell WiFi nodes "you can transmit" or "wait". There are several mechanisms in play there. WiFi networks try to avoid collisions like the old Ethernet and in order to avoid the hidden node problem (read the chapter on the Aloha protocol on "Computer Networks" by A.S. Tanenbaum) it uses a mechanism called RTS/CTS. Especially before sending long packets that might tie the radio spectrum for a long time, an exchange warns that it will happen. Also, modern WiFi versions can detect signals from older versions. All of this helps to prevent collisions. I can imagine situations in which it might cause some issues even if negligible. Not suggesting that it could cause a wireless apocalypse or anything like that. As far as I know neither the FCC nor the European authorities perform a protocol level verification of WiFI equipment, for instance. Moreover, being a license free band shared by multiple technologies I think they mostly verify pure radio parameters like transmission power levels, out of band spurious radiation, maybe spectral masks and duty cycles in order to help, not guarantee, coexistence with other technologies, etc.

I don't think they will conduct a complete protocol verification. But there are people much more knowledgeable than myself in that regard here. As far as I know they check for spurious emissions, power levels and spectral masks. But, again, I am not anything remotely resembling an expert on device certification, much iess on how it is done in USA

Adaptive frequency hopping is not "messing with the spectrum" indeed. It's being more efficient. But playing with the RTS/CTS mechanisms, which is an entirely different matter, could be a problem in some environments.

As for the bag I got the Sachtler SN607. Despite the small size it's really spacious, and the front pocket can accept a folded MDR-7506 and a small flashlight even if a bit tight. For nature recording I can even use the extra division in the main compartment for a pair of standard size binoculars (8x42). One of my requirements was compatibility with the optional power sleds for the MixPre in case I eventually get the L-mount adapter (the USB C connectors make me a bit nervous). I haven't got the adapter yet, but the SN607 is really roomy for its size.

Naughty, so, really playing with the RTS/CTS mechanism I can also imagine situations in which messing with the 2.4 GHz spectrum might get you in trouble. For example, shooting an interview in a place that makes a heavy usage of WiFi such as a hospital or even some industrial settings that make a heavy usage of wireless networks for inventory control, etc. Now, speaking of desensitization. Does the receiver include sharp front end filtering? I have seen situations in which WiFi equipment was unable to work due to a relative powerful continuous carrier transmitted by a microwave motion detector. I know most nowadays work on 10 GHz, but this one was a powerful signal on 2.4. I have also found issues with analog sound/video transmitters working on the 2.4 GHz band. At least the old ones I have found somewhere transmit old fashioned carriers with their sidebands. Screenshot attached from a really basic spectrum analyzer (a WiPry from Oscium) I guess in many run and gun situations you can't properly RF-sanitize the environment, so such evil equipment could ruin your day.

Speaking of what, I've been shopping for an audio bag lately and I got the Sachtler SN607. The puzzling thing about the Sachtler website is, the audio bags are not visible. If you go to the "Bags" section you will see the usual camera bags, but no audio. You must do a search (searching for a particular model like SN607 or "audio bag") to find them. The Spanish dealer had it in stock but I am wondering wether they are planning to discontinue them...

I'm not sure it's a bad thing, apart from the risk of someone buying Vitec (like Samsung has acquired Harman because of who knows) and destroying part of it. Curiously they own three different tripod manufacturers (Manfrotto, Sachtler, Gitzo and the more modest Joby) and as far as I know they have respected their quite different product lines. You wouldn't guess they belong to the same conglomerate. As for Rycote compared to Petrol, Rycote is 100% audio, nothing else. Why would they purchase it? Basicly the high end of that audio market is shared by Cinela and Rycote, right? At the same time there are lots of links between Rode and Rycote with Rode addressing the low end. I could imagine a popular name like Manfrotto relseasing low end versions of Rycote products for podcasters, youtubers, etc, but the Rycote name is so valuable.