Problems with the Zoom H2 Line Input

Small portable recorders have really established themselves on the market now, and my old Zoom H2 (firmware 1.90) is becoming a bit worse for wear. I've had it for a long time and found it to be an incredible useful device to have in my recording kit, even though I only think of it as 'consumer' as opposed to my 'professional' sound kit. That said, when used in the right way, I've got good recordings with it. I always combine it with my 302 or 442 mixer and have it running as a backup recorder when I'm running sound to camera - such that I have a 2 channel version of the mix (if not the iso tracks) incase there is a problem with the link to camera, or the camera itself.

The Nightmare before Christmas

Recently I was using the H2 (and 302 combo) to record some very dynamic sounds and I started noticing some audible clipping on the peaks on the headphone output of the H2 and something very odd about the meters on the H2 - they appeared to be limiting at about -8dB below full scale. So I did the obvious checks of the limiters on the H2 (they were off) and checked my limiters on my mixer and the limiting on the H2 was happening even before my limiters had kicked in on the mixer outputs. Something was not right.

I did all the usual checks, and the recording level was set to its usual value of '77', which aligns the input of H2 to match -18dB tone with the tape output level of the sound devices mixers. So all seemed fine technically, yet the meters seemed to be hitting some form of brick wall limiter and the audio was clipping.

Expect the unexpected

I returned home and started experimenting with the H2 and researching, and found something fairly gutting: when recording to the H2 Line input, the input level control does not alter the gain structure, but just shifts the recording range and "offsets 0dB" - meaning that it clips at a value less than 0dB. It's such a terrifyingly stupid concept and so fundamentally wrong, that I had to fully test it out to confirm what I was hearing. These tests were carried out with me speaking into a MKH60 mic and steadily increasing the gain until the output from the mixer +20dBu.

H2 Line Input Level 100

The first test is with the line level set to 100 (it's default setting): -18 dB does not correctly align, on the H2 meters, it correlates to about -12dB But you can see as the signal increases from the mixer, the recorder records all the way up to 0dB(FS); and essentially clips in the usual manner - but means that I'm (in essence) losing 6dB of recording range as this is now 'over' the range of the recorder and with any other recorder I'd just reduce the input gain, such that the range matched my analogue mixer.

H2 Line Input set to 77

Now the input recording level has been reduced to 77, which nominally lines up -18dB tone on the scale of the H2. Yet as the signal increases from the mixer, the recorder starts clipping the signal at about -7dB(FS). So, even though I've supposedly reduced the input gain of the recorder, it is now internally clipping the signal at about -7dB(FS) - and this clipping sounds much worse than that at 0dB with the internal limiters enguaged.

And as the recording level is reduced to 60, the effect is even more pronounced.

H2 Line Input set to 60

Pay your money / Take your choice

So now I have the dilemma of what to do, I've used the recorder for years for back ups and rarely had to dip into them and also those recordings have been much less dynamic than those I've made recently. There are two ways to work now to try and keep the H2 as a reliable backup: Firstly keep the recording level at 77, and to set the limiters on the Sound Devices Mixers to be cutting in before -7dB(FS) and so prevent the clipping with the H2. But this is then adjusting how I record just to suit the quirk of my backup recorder; which feels like the tail wagging the dog to me. Or Secondly, leave the levels at 100 on the H2 and let the internal limiters (which are not great) on the H2 stop the peaks that are beyond -6dB(FS) from the mixer - which to be fair would usually be few and far between. Neither is really ideal.

I think the simple answer is that I've got what I paid for, the £120 recorder is a consumer piece of equipment with flaws that I have to live with - but at least I know about them now. When (or if) I decide to use it again, I'll have to be very aware of the limitations.

G
13 January 2013

Location Audio Kit Announced at NAB 2011 (a summary)

Firstly let me stress that I'm not at NAB, I'm at home (filling a skip if you must know, but I'm not bitter). So all the information I'm pulling together here, is a summary of the Tweets, RSS feeds, Press Announcements and Viscous Rumours that I've read / heard over the past week or so that relate to location audio equipment being announced during the NAB show; Apologies for those sections that are apocryphal, or at least wildly inaccurate.

So, in no particular order...and I know I've mentioned Sound Devices and Sennheiser before, but I've included them in here for completeness.

Fostex DC-R302 - Compact 3 input mixer, 2 channel SD recorder designed to fit underneath DSLR's.

Sound Devices Mix Pre D - Compact 2 channel mixer, USB Interface, AES Digital outs, fits under DSLR. Mention has to be made here of the new image recorder released by Sound Devices...

Sanken CS1e - A new revision of the sanken CS1 shotgun mic, improved low end, improved off axis rejection, and a bit lighter - (video clip courtesy of Trew Audio - nothing on the Sanken site yet).

Shure VP89 Modular Shotgun - Now this does look interesting..an RF condenser from Shure, that looks like it is modular in construction and offering 3 capsule designs and various response patterns, offering increasing directionality.

Zaxcom Nomad -  (Not sure if this was released pre NAB) Zaxcom enter the over the shoulder field recorder  market with an incredibly well specified machine. Various build options from 4 tracks / 6 inputs upwards, offering more tracks via the digital inputs. This includes fully featured timecode, making it look a great machine to have on the trolley, and then pick up and run with. Interesting to see the "power" specifications were that it only quotes 1-3 hours of usage from 6AA - other powering options via the Switchcraft L712 input from a standard NP1 style battery power range (8 to 18 Vdc).  Mixer panel looks a little sparse, assuming all controls like LF cut / Panning etc are menu driven for each channel.

Aeta 4Minx -  A new mixer recorder from the French company Aeta. I reviewed their 3 channel mixer a fair few years ago (the Mixy) and I really got on with it quite well - and it did sound good.   The 4Minx looks a little similar, but now a 4 channel recoder (or is it 4 channels + 2 mix channels, description on the web site seems inconsistent?) with many many connections for interconnectivity. Certainly looks like a flexible beastie and there is the usual 5 pin lemo for timecode connection.

Sennheiser MKH8060 / MKH8070 - New development of the MKH60 / 70, now in the modular 8000 series

Countryman B2D - a very VERY small lavaliere mic from Countryman. Cardioid response pattern, with additional grill that can change it to hypercardioid.

Huge "Hats off" must go to Trew Audio who've covered the event on their site, and using lots of media formats to promote the show and themselves very well. There's bound to be more stuff that I've missed from the press cuttings so...I'll edit this page and add if I'm aware over the next couple of days.

G - 13-April-2011

New Location Microphones from Sennheiser

I'm a bit of a fan of Sennheiser location microphones, so it's always good to hear that they have once again advanced and broadened their equipment range. One of the reasons I like them so much is that their condensers work on the RF principle (explained here and here) which makes them inherently more resistant to moisture - which is a prime consideration when working out in the field.

The two new microphones are from the recent 8000 series, which are based on a modular design. The new 8060 and 8070 capsules are designed specifically for location audio work, both being based on the successful  MKH 60 and 70; the 60 being the original successor to the "industry standard" MKH 416.

MKH 8060 capsule

The 8060 is the physically shorter of the two new capsules - short shot gun -  and has a wider acceptance angle, a tight hypercardioid if you will. The original improvements of the 60 over 416 changed the frequency response of the off axis sounds, making it a much nicer microphone to use indoor (due to reflections) - and slightly less harsh, as the presence hump had been lessened. As the 8060 is modular, this is just the capsule that would then need attaching to an XLR adapter for a complete conventional microphone; however with the 8000 series design there is the option for an LF Cut / attenuator module, AES 42 digital converter module (making a digital microphone), or remote attachment of just the capsule using a lightweight cable - useful for reducing weight and length - a definite consideration in tight corners when booming or mounting on top of a camera.

MKH 8070 capsule

The MKH 8070 is the long shot gun microphone, with a much tighter pickup pattern, and extreme directionality. Designed for much more remote placement. Again, though as modular, connects to all the other modules I've just mentioned.

Although the 'sound' of the Sennheiser range is sometimes said to be inferior to the Schoeps or DPA - there are very few recordists that I know that don't have a Sennheiser microphone in their kit - purely because of the reliability. When I bought my first "proper" location microphone, I bought the MKH 416, because I asked a number of my far more experienced colleagues:  "If you could only own one microphone, what would it be?" - and the answer was either the MKH60 or MKH 416.

I hope that the 8060 continues this pedegree, with the additional benefits that the modular design of the 8000 series has to offer - I look forward to hearing them.

G

12 April 2011