Zoom isn’t afraid to innovate, and while the F8 might not usher in a new field recorder category like the H4, it’s certainly dreamt up a dramatically new pricepoint for it.
Review: Greg Simmons
Zoom blipped onto my radar in the early ’90s with its nifty little 9002 guitar effects processor; a device small enough to hook onto a guitar strap with a remote control that mounted on the guitar body. Although I admired the innovative thinking, it was of no use to me because I’m not a guitarist. Zoom didn’t have much to interest me as a sound engineer until it released the H4 Handy Recorder in 2006 — its first venture into the recording market. With two built-in microphones and two XLR mic inputs in a battery-powered handheld recording device, the H4 ticked a lot of boxes in the price-versus-performance checklist.
I’ve met many users who swear by their H4s, and just as many who swear at them. The design was not without its flaws: the user-interface was clumsy, the LCD screen was small and dim, and the noise of the external mic preamps rendered them useless. Then there was the bizarre stereo technique used for the built-in microphones; supposedly a coincident pair of cardioids at 90 degrees, but with the diaphragms spaced a small distance apart and facing towards each other in what I referred to as the ‘cross-eyed’ arrangement. The H4’s manual went to great lengths to incorrectly explain why this was a good technique — something I’m sure Zoom copped a lot of flak about.
The H4’s successor, the H4n, addressed all of those issues. The user interface was improved with important buttons relocated and a larger, brighter screen. The external mic preamps were also improved, and the cross-eyed mic technique was replaced with a truly coincident pair. The H4n’s user manual went to great lengths to correctly explain why this was a good technique, and in the process criticised the H4’s cross-eyed technique… while carefully avoiding self-incrimination! Not only did Zoom get the microphone technique right, it developed a clever method to change the subtended angle from 90° to 120° by simply rotating the individual microphones. I still consider it ingenious.
The point of starting this review by discussing much older products is because it says important things about the people at Zoom. They’re not afraid to innovate, they take user-feedback seriously and they are fast learners. Comparing the original H4 with the more recent and similarly form-factored H6 shows just how willing Zoom is to respond, improve and innovate. Which brings us to the F8.
F FOR FIELD
The F8 is an eight-input, 10-track field recorder designed for over-the-shoulder use in location sound recording for film and video. F for ‘field’ as opposed to H for ‘handheld’, I assume. It has eight mic/line inputs that can be recorded to eight separate tracks, and an internal eight-into-two mixer that allows a stereo mix to be recorded at the same time (hence, 10 tracks). The stereo mix can also be routed to three different outputs — headphones, main, and a sub output for feeding a DSLR or the like. Each features an individual output level control and peak limiter.
The F8 can record 16- or 24-bit .wav files at sampling rates from 44.1k to 192k, and mp3 files from 128kbps to 320kbps. The F8 has two SD card slots and is capable of recording to both cards simultaneously. It can also record different things onto each card in real time – for example, multitrack files on one card and a stereo mix for the dailies/rushes on the other. It also features a dual record option when using four or less inputs that allows each input to be recorded to two separate tracks, one at a lower level as a safety in case of excessive levels.
The whole thing weighs under 1kg without batteries. It has comprehensive timecode capabilities, can be remotely controlled by iOS devices, and can also be used as an audio interface with a Mac, PC or iPad via its USB port.
ZOOMING IN & OUT
The F8’s preamps are padless but offer up to 65dB of gain on a single rotary control (+10dB to +75dB on microphone inputs, and -10dB to +55dB on line inputs). The minimum microphone gain of +10dB was not a problem during testing, but experience with other padless preamps has shown that a minimum gain of +10dB can still be too much. It’d be wise to carry a couple of in-line pads if you plan to use microphones with high sensitivity on loud sound sources.
The combo inputs automatically switch to line when a 6.35mm jack is inserted. Phantom power is switchable on each individual input, with a global option of using either +48V or +24V; running the latter, when possible, conserves battery power. In a nod to the consumer market, each input also offers Plug-In Power. Also known as PIP, it’s commonly provided by smart phones and similar devices to power electret condenser microphones with unbalanced outputs. Unfortunately there was very little information about its implementation in the manual.
Each input has a high-pass filter switchable from 80Hz to 240Hz in 10Hz steps. I can find no mention of the filter’s slope in the manual or otherwise, but its wide range of cut-off frequencies allows it to do the job for those times when you must use a HPF during capture rather than waiting until post. There’s also a comprehensive limiter on each input with options of hard or soft knee operation, adjustable threshold (-2dBFS down to -16dBFS), adjustable attack times (1ms to 4ms) and adjustable release times (1ms to 500ms). The ratio is fixed at 20:1. It is, after all, a limiter.
A welcome feature that is missing on many contemporary devices is the ability to invert the polarity — incorrectly labelled ‘phase invert’ on the F8 but you get the idea. In addition, each input has a built-in delay adjustable from 0ms to 30ms in 0.1ms steps (perfect for synchronising different input sources), stereo linking capabilities between adjacent channels, optional MS decoding on record or monitoring, and a very useful PFL button that offers a choice of PFL or Solo behaviour.
How is it possible to offer so many input channel features at such a small size and low cost? The first stage of the analogue input path is a combined microphone preamp and A/D converter. From there on, all processing takes place in the digital domain. Some readers might assume it’s pointless having the limiter after the A/D converter, but through clever use of digital gain staging and by making the limiter work directly on the preamp/ AD converter (rather than its own variable gain cell) it’s not a problem. This technique has been used by Nagra and others in recent years, and requires a shift away from traditional analogue thinking to fully appreciate.
FINDING FINGER LOCATIONS
One of my major bugbears with location recorders is the user-interface; the likelihood of fiddliness increases with inverse proportion to panel space. There is just enough front panel room to access all of the controls with reasonable certainty although, as with any small piece of technology, keep an eye on what you’re doing if you have particularly wide fingers!
The F8 relies on a simple method of navigating through its numerous menus and functions based on a Menu button and the Select Encoder — a rotary dial with a built-in press button. Pressing the Menu button opens the menu system. Turning and pressing the Select Encoder does the rest, assisted occasionally by one or two of the transport control buttons.
The menu system accesses all the features of each input channel in a feature-by-feature manner. For example, changing the settings of the HPF for one particular channel via the menu system means selecting HPFs, selecting the channel, making the adjustments, and then pressing the Menu button to reverse out and move on. This back-and-forth menu navigation gets a bit tedious when you’re trying to set up all the input options for one channel in particular.
Thankfully, the F8 offers a much quicker method: pressing the PFL button of any armed channel brings up all of its settings on one screen, including input gain in dB, phantom power, high-pass filter, limiter, polarity invert, metering, monitor mix fader and pan. It’s a much faster way to quickly tweak the parameters of an individual channel. My favourite method of working was a hybrid of both — use the menu system for setting global and system parameters, and the PFL function for controlling channels.
When not accessing the menu system, rotating the Select Encoder provides access to the internal eight-into-two mixer along with four customisable metering views. The meter ballistics include Peak, Peak + VU or VU only, with adjustable peak hold times.
It’s a testament to Zoom’s interface design that I didn’t open the manual until after making many test recordings with the F8. In fact, the only reason I consulted the manual was to double-check facts while writing this review. Oh, and also to find out how to make the Bluetooth connection to an iOS device. Speaking of which…
IN THE iOS MIX
To control the F8 remotely via an iOS device requires downloading the Bluetooth driver from Zoom’s website, copying it onto an SD card, inserting it into the F8 and delving into the menu system. Of course, you must also install the appropriate app in your iOS device.
The iOS app provides a much more spacious and faster interface than the F8’s front panel but follows the same menu system so there’s nothing new to learn. The downside of that approach is that, aside from multi-touch mixing, it fails to take full advantage of efficiencies offered by the iPad interface. For example, touching a menu item to reveal another menu with two options that could’ve simply been presented as a dropdown menu on the first touch. Hopefully later versions of the app will be more refined.
One of the knocks on the F8 is its limited hardware mixing control. Which for some applications, is a must. The app at least provides a means of multi-channel mixing, while letting the F8 do what it does well; pack in loads of channels and tech at a ridiculous price point.
FOUND SOUND QUALITY
The problem with reviewing the sound of audio gear these days is that nothing sounds ‘bad’ per se; what’s ‘bad’ today sounds amazing compared to what was ‘bad’ a decade ago. Good quality mic preamp and converter chips are highly affordable to manufacturers, and are therefore making the tonal differences between the cheapest and most expensive gear harder to discriminate. Judging differences requires a wider variety of sound sources to highlight them, and considerably more listening time. To that end I gave the F8 quite a hammering during the review period, making numerous recordings including direct-to-stereo piano, multitrack jazz, outdoor field recordings and dialogue.
In some cases I used Y-splits and made simultaneous level-matched recordings to other machines to make valid comparisons. Those machines included a Nagra 7, a Sound Devices 702 and an Apogee Quartet. It’s worth bearing in mind that the Nagra and the Sound Devices are both two-channel machines costing considerably more than the eight-channel F8, while the Apogee is quite a different device but worthwhile for the sonic comparison.
Considering all that the F8 packs into its small size and price, and the fact that I could find nothing to criticise in terms of features, build quality or ease-of-use, I was expecting its sound quality to be the disappointment. It would’ve justified the old adage, ‘you get what you pay for’ and made this review a whole lot easier. The truth is, however, that I honestly cannot be critical of the F8’s sound quality.
Subjectively, it sounds marginally brighter than the more expensive Nagra 7 and Sound Devices 702, but that brightness manifests as a subtle sheen that provides an enhanced sense of clarity without any suggestion of harshness or brittleness. I did not find it tiring or fatiguing. At the same time, the F8 does not have quite the same fullness in the lower midrange as either of the other machines. The end result is an ever-so- slightly ‘lighter’ sonic presentation. I must stress that these differences are very subtle and should be considered more as a characteristic tonality of the F8 rather than a criticism.
You can judge for yourself by downloading the comparison sound files I have provided with this review at soundcloud.com/audiotechnology.
I should add that these sound judgements were all made after loading the files into a DAW and monitoring through decent speakers and headphones. The built-in headphone amplifiers on most location recorders should never be trusted for this kind of comparison, and especially not the F8’s headphone amplifier. If the device has any weaknesses, the headphone amplifier is it. Listening to F8 recordings through its internal headphone amplifier, and then through a decent headphone amplifier, was quite a surprise. I guess headphone amplifier chips have not yet made the same advances as mic preamp and A/D chips.
Zoom’s F8 is a feature-rich multitrack field recorder with an internal complexity that has been rendered simple through clever interface design. It is surprisingly straightforward and free of any operational quirks and gotchas, and its clever features reflect a design culture that has spent many hours listening to end users. It’s ruggedly built, weighs around a kilo with batteries installed, feels solid and confident, looks good and sounds good. Add an iPad for remote control and it gets even better.
All things considered, it’s fair to say that the Zoom F8 is a game changer. How it stacks up sonically against competing devices is a matter of opinion, but anything costing more than twice the price of the F8 is going to be a hard sell from now on.
I fully expect to see the F8 in the kit of every serious location sound engineer in the near future — either as their primary recording machine or as a cost-effective extension or backup.