My new Rode NTG1 is hissing.....

[Marco Giordani]

Hello,

I just received my Rode NTG 1 to replace my Sennheiser ME66. The reason is not because I don't like the sound of the ME66 it is just too long on my Sony PD 150 and gets in the way when I am shooting something right up close to the lens.
When I compared the two mic's I noticed a static type interference on the Rode during silent times. I plugged in the mics separate and the Rode definitely has a hiss or static sound when is is silent.

Anybody have any suggestions? (I am not an audio pro)
My sennheiser came used with my camera, so its is the only mic I am familiar with.
(My headphones that I monitor camera audio with are the Sennheiser HD 280 pro)

[David Morgan]

My unit does not hiss. Signal to noise ratio is one thing but if you can put the two mics into the same channel, one after another and prove that the Rode exhibits very noticable hissing, it's possible that the mic has a defective component like a capacitor. I used to repair Sennheiser 416's. This was a common problem with hissing and crackling.
The other thing to consider is mic pre-amp gain. do u have to turn up the gain to max on the camera? Camera pre-amps are notoriously noisy. Anything unusual like that happening?

[Steve House]

You might be hearing the preamp noise of the camera. The ME66 has a rated output of 35mV/Pa. The Rode has an output of 15mV/Pa, less than half that of the Senny. So to get the same levels in the recording, the preamp gain has to be substantially higher with the Rode than with the Senn, and that would raise the level of any recording circuit noise at the same time.

[Shaun Roemich]

Further to what Steve says, I can vouch that my PD150 (now released to some students from the local community college for a song) had the ABSOLUTE NOISIEST preamp I've ever heard if it was even remotely turned up.

[Marco Giordani]

Thanks everybody for your quick response and very useful information.

After doing more tests I think it is the preamp noise of the camera. I usually keep the audio manually for ch1 and ch2 around the middle of the bar on the camera display. When I got my Rode I raised it up because I'm used to getting louder response with my ME66.
With it raised up I did notice some noise on the ME66, but very little.

I have some question if I may;

What is "Signal to noise ratio"? (is that what I just figured out above?)

How can I find out more about what these ratings mean....35mV/Pa & 15mV/Pa and where to look on the specification chart for other mics concerning these ratings?

What mic can I get (for on camera) that is as good as the ME66 but not as long?

Thanks,
-marco

[Steve House]

Originally Posted by Marco Giordani

Thanks everybody for your quick response and very useful information.

After doing more tests I think it is the preamp noise of the camera. I usually keep the audio manually for ch1 and ch2 around the middle of the bar on the camera display. When I got my Rode I raised it up because I'm used to getting louder response with my ME66.
With it raised up I did notice some noise on the ME66, but very little.

I have some question if I may;

What is "Signal to noise ratio"? (is that what I just figured out above?)

How can I find out more about what these ratings mean....35mV/Pa & 15mV/Pa and where to look on the specification chart for other mics concerning these ratings?

What mic can I get (for on camera) that is as good as the ME66 but not as long?

Thanks,
-marco

The ME66 is relatively short as shotguns go so finding a shorter alternative is going to be tricky.

The ratings you asked about indicate the relative output voltages of the two mics at a standard sound pressure level, mV being millivolts and Pa the pressure in Pascals. A sound pressure level of 1 Pascal corresponds to a loudness of 94 decibels. So if you set up the ME66 and the Rode side by side and subject them both to a sound of 94 dB SPL, the Senn will output 35 millvolts while the Rode will output 15 millivolts. In other words, the Rode puts out a signal a little less than half as strong as the Senn when they're exposed to the same sound. Note that high output levels in and of themselves do not necessarily mean one mic is better than another. For example, the $1500 Sennheiser MKH416 outputs 25mV/Pa and the $2500 Schoeps CMIT-5u outputs 17mV/Pa, both signifigantly lower output than the ME66, yet there's no question they're much higher class mics overall. Many workers consider the ME66 to have a rather marginal sound quality, tending to be a bit harsh, and believe the Rode to be the overall better sounding of the two.

To find ratings to compare, the best source is the manufacturer's web site. Rycote also sponsors a data site - Microphone Data - that collects many of the various manufacturer's data sheets into a single searchable database where you can compare them - very handy. The site also has a good reference library and one of the pdfs you'll find there is an outstanding guide to understanding the mic data such as sensitivity and signal/noise ratio -
http://www.microphone-data.com/pdfs/...ic%20specs.pdf

[Marco Giordani]

Steve thank you for your follow up information. It is much appreciated.

[Steve House]

I should have added, the BEST solution to the "mic is too long" problem is to get the darned thing off of the camera and out within touching distance of the subject where it belongs. It's an incredibly rare shot where an on-camera mic is the appropriate solution. I know you see 'em on just about all ENG cameras made but they're really only there to capture ambient sounds or for run-and-gun news gathering when there's simply no other alternative other than missing the story altogether and bringing it in with crappy sound is still preferable to coming back to the studio empty handed. A shotgun mic is NOT like an audio version of a telephoto lens magnifying distant sounds - sound just doesn't work that way.

[Allan Black]

One of the defining features for 'good sound' for video work is ... a second operator, an audio person, a boom op.

Most prosumer one man camera ops have a difficult time recording good sound, if you're really going to get into it, try training someone for important shoots. Then you can run a boom and that's not easy either, it also takes practice.

Eventually your videos will show it because sound is 70% of what you see on the screen.

Cheers.

[Shaun Roemich]

Steve and Allen bring up excellent points however the major issue here is the camera pre-amp. Even exacting boom operators won't help the issue here. If your operators use external recorders and send you a reference signal, you'll get fantastic audio on the external device but your camera recorded sound will continue to be bordering on unusable without extensive audio post to minimize the noise floor. Either get 2 system sound or upgrade the camera.

[Ty Ford]

Originally Posted by Shaun Roemich

Further to what Steve says, I can vouch that my PD150 (now released to some students from the local community college for a song) had the ABSOLUTE NOISIEST preamp I've ever heard if it was even remotely turned up.

Hey Shaun,

We had one show up at one of my workshops a few years back. Turns out the biggest problem was the camera-mounted mic. It was really horrible. When I plugged in my 416 Sennheiser, everyone's jaw dropped at how much better it sounded. A night and day difference. Did you try other mics/mixers with the PD150?

Regards,

Ty Ford

[Kevin Walsh]

Hi Marco,
Have you looked at the ECM-673? http://bssc.sel.sony.com/Broadcastan...es/ecm-673.pdf
I use them on all of my cameras. Good sensitivity, low noise, short, and relatively inexpensive.



update: I just looked at the output spec for this mic and noticed that it is the same as the Rode, so this wont help with the hiss.

[Shaun Roemich]

Hey Ty, my Sennheiser ME66, Sony ECM-50, Shure SM58 and a workhorse EV that the paint has come off of ALL had background hiss issues. Of course, the lower the output level of the mic, the more o an issue it seemed to be. The ME66 was, if memory serves, the LEAST noisy of the bunch.

Interesting point though, I wonder if mine wasn't one of the earlier ones with the known preamp problem.