Noise Cancelling Headphones

Duncan Hutchins

New member
I am a retired sound engineer with UK City & Guilds qualifications. I work part time for live bands providing sound engineering, audio and video recording and DMX-controlled lighting. I frequently need to use headphones at the mixing desk, not only to monitor the main stereo mix going to the PA which obviously I can hear anyway with 'the naked ear', but also specific sounds which may need to be tweaked, such as an individual instrument or singer within a live performance. The problem I have is that when mixing fairly close to a normally loud rock band, it's nearly impossible to distinguish what's in the headphones from the overall sound coming at me from the PA, on stage amps, etc. Even with relatively high isolation headphones such as the Sennheiser HD250 (?) I cannot stop high levels of the band's s ambient sound reaching my ears, confusing what I'm trying to actually to focus in on. These days there is a good choice of noise cancelling headphones out there, using both active and passive noise cancelling technologies, some quite affordable and some out of my reach price-wise. I have 2 questions: could I simply set up a stereo mic close to where I'm working and put that signal through a small mixer, phase reverse it and then send it into my ordinary headphones, alongside the individual signal I'm actually trying to focus on? My theory is that the ambient sound would cancel out with the same sound being present in my headphones, but phase-reversed, leaving only the sounds I want to hear. I realise that this would never work 100%, but would it produce a worthwhile reduction in 'air born' unwanted sound from the whole band, and to what extent? Second question: Has anyone on this forum had good noise reduction results in live music situations with a reasonably priced noise-cancelling headphone that's available? Assessment, brand and model please. NOTE: when I use the word 'noise' I'm referring to the band's actual front of house sound as heard naturally in 'free air', same as the audience near to me hears, not some nuisance 'hum', 'buzz' or other unwanted electronic artefact. Cheers - Duncan Hutchinson, Devon, UK
 
I've worked in theatres with loud acts and had great success with noise cancelling mics on the cameras, and they make life much more tolerable, but no way would I be able to use them to make EQ choices or other balance choices. They are really good for reducing volume but they really don't do music.

Can you not simply wear a decent pair of IEMs? I've found the ones I wear on stage serve two uses - they give me excellent audio quality and keep out the stage sound, but also work fairly neutrally as ear plugs - I can pull the plug out and the level is nice - but these also make judging 'tone' very tricky. The best headphones I've used to keep out sound live are Beyer DT100s - (or 150's) and these work for me out front - decent quality and modest reduction. My son has some Bose noise cancelling headphones and I thought they'd be good, but the sheer volume of storage sound is just too much for them and the audio quality is just nasty and harsh. Not what they're designed for. In normal use they are pretty good.

I have a pair of pit-lane style headphones I use on radio comms for use backstage, and these have an input for music - phone, iPod etc - and although not brilliant quality I get used to the sound - BUT - they clamp your head like a vice to achieve the isolation.
 
Have you considered a "booth"? A 3 sided structure, transportable and made of acrylic sheet. I would guess 6mm sheet or better would give maybe a 10dB reduction in the direct sound? That might just be enough.

Or! Sit in the van. CCTV is cheap as chips these days. On a serious note, have you checked your SPL exposure? Us old 'uns need to preserve what hearing we have left!

Dave.

Dave.
 
many thanks for that. Yes, an acrylic booth would give a useful reduction, and in fact if I get the chance I'll always colonise any likely looking structure that happens to be around, be it a brick garden wall or a shed, just so long as I can see. Most of the time a dedicated booth as you describe would probably be considered intrusive, e.g. a wedding. Unlike the actual performers, engineers are supposed to be 'not there' visually speaking. Yes, I do check my hearing from time to time using sine waves from an adjustable oscillator. I'm now down to 14kHz upper limit, but if I can hang onto that, higher frequencies are not really all that important in a live situation, and nobody who knows what they're talking about has ever found my live recordings lacking 'sparkle'. But a worry all the same.
 
Back
Top