How about the audio performance of the HMC150?

A

Averdahl

Well-known member
In most clips i have seen from the HMC150 the original audio is either replaced by music or removed completely.

So, how is the audio performance from the HMC150? The testings i have done seems to indicate that the audio is indeed very hissy, even if the surronding sounds are high. When the surronding audio is high the most cameras hiss almost completely "disappear", but with the HMC150 it is still very noticable.

I dont own the camera yet, so my testings has been limited. I tested with a Sennheiser K6+ME64. That microphone is hot, thus making cameras hiss lower because the audio gain can be set quite low. Despite that i noticed the high hiss levels of the HMC150 which confused me a bit.

For the record, i have listened to the clips on a computer, so i am not talking about hissy headphone outputs.

The image quality of the HMC150 is really fantastic, thats why i want good audio as well. I want the camera but the audio is holding me off from buying it right now.

What do you users think about the audio of the HMC150? :)

/Roger
 
I havent noticed any hiss and think the audio is quite good. i think you would need golden ears to be able to tell the difference from 150 audio and say DVX audio. my $.02
 
I agree, haven't noticed any hiss. I've been quite impressed with the sound from the built in mics as well.
 
Has anyone else used the K6+ME64 with the HMC150? I'm about to purchase that setup for a feature doc I'll be starting production on in the coming weeks. Hiss would be a problem obviously, so I wonder if anyone else has experience with that setup?

Also, has anyone used a Senn 500 G2 setup with the HMC150 yet? Planning on doing that as well for the doc on conjunction with the ME64+K6, so just want to see what people's experience is.
 
There's no reason you should hear any hiss from the 150, sure it's not native PCM, but it does sample audio at 16bit, 48Khz and compresses at 384kbps which is pretty high IMO.

I usually capture our sound via outboard Zoom H4 series digital recorders, encoding in the lossy MP3 format at 256Kbps and don't detect any anomalies in the sound unless we process re-compress in MP3 again.

I guess it depends on your intended audience and what they're going to be listening to your audio through.
 
I've used the Senn 500 first generation with no problems but i would probably choose a different mic over the ME64. my AKG CK93 works well with the 150.
 
Evro, with the H4, are you importing all of that audio to sync with your footage and expanding it by 100.049%? I've read it goes out of sync at a constant rate that can be corrected with that conversion. Since I'll be shooting a doc, I feel like that would be a headache to have to sync all of that.

And matt s., do you use the supplied mic holder or use a shock mount with the cold shoe on the HMC150? And you don't experience any handling noise? If so, sorry to be nit-picky, but could you tell me which cold shoe/shock mount you purchased and how long of an XLR cable you needed?
 
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Yep the Zoom series recorders have a sync problem, but I've learnt to deal with it over the last year or so by expanding the tracks as you've said.
Once I recover financially after buying two HMC-150s the very next thing I'm investing in is a pair of high quality field recorders. Possibly the Sony or Marantz ones, however this time I'm going to make sure the are sync accurate like my $80 Iriver voice recorder.

The DVX had the best shock mount I've ever seen, whereas on my Canon & JVC cameras I do get handling noise from the standard mic mount.
 
Roger I have to agree. With the built in mic there seems to be a lot of that ambience hiss. I just got the camera and am trying to figure out if its normal...since other people are like "sounds awesome..love the sound...".

I wonder if this is also with external mics? The built in mic has it but do you still get hiss when a shotgun is used?
 
I shot ~50' with the 150 yesterday in the studio; one channel was via Sony radio mic; the other via on-camera Sony ECM-670 (medium length shotgun). All sound is excellent after transcoding to Pro Res 422; sounds great to me, and I have recorded a lot of sound in my day (and I have a lot of mics here too).

Frank, where were you recording that atmos? Or are you talking about the base noise of the circuits when the gain is turned up? Try recording something typical of your work---my guess is that you won't hear anything unpleasant.

As well, I found the ALC circuits handle overload very elegantly, which was unexpected. cheers, kl
 
I shot ~50' with the 150 yesterday in the studio; one channel was via Sony radio mic; the other via on-camera Sony ECM-670 (medium length shotgun). All sound is excellent after transcoding to Pro Res 422; sounds great to me, and I have recorded a lot of sound in my day (and I have a lot of mics here too).

Frank, where were you recording that atmos? Or are you talking about the base noise of the circuits when the gain is turned up? Try recording something typical of your work---my guess is that you won't hear anything unpleasant.

As well, I found the ALC circuits handle overload very elegantly, which was unexpected. cheers, kl

***UPDATE***

Today I have been listening more closely to more of the audio, and there IS a reasonably pronounced floor noise. I have a friend here with me who is an expert Pro Tools editor and sound engineer; we are going to analyse the two recorded channels and see it we can determine where this is coming from.

We will shoot some video with no sound input (to try to assess the inherent noise from both the circuits and the conversion to Pro Res (all part of the possible sources); then with the shotgun only (this mic requires phantom power, too; another possible source), with the radio mike only (I have used these particular mics on many shows in the past, and they perform very acceptably, so are a known quantity), and with both sources being recorded, in case there is any unintended interaction.

In mentioning this, I don't want to imply that the recorded sound is poor in any way; it is just that the OP's original question about hiss or floor noise may need further investigation.
 
Finally! :)

Kit_L you are on track of exactly what I have been investigating. Most video people say "sounds great!" but if you listen with an audio ear its definitely there.

Easy test - record set to mic inputs and then use no mics. I tested this way by bringing the clips into Logic Pro and striping out the audio track, listening and then examining. There is a level of noise..not sure what to call it..I've called it fuzz cause its not really a buzz. Some call it white noise or as you call it floor noise.

(I've also started thinking that some people's headphones / monitors if they were not too high end would not notice it as much, perhaps its out of the frequency, just a thought)

This noise is most noticeable in the built in mic. Recording in a quiet room with the headphones set to the halfway mark, the floor noise is extremely noticeable. I was willing to give it a pass, thinking, well I am going to get a good shotgun mic anyway, until I started testing XLR mics and noticed the noise, while reduced, was still very much there, even when I unplugged the mics.

I called Panasonic tech support, and while the guy seemed knowledgable, he said this is the first he has heard of it. I am curious because as only having the new camera a few days, I cannot figure out if this is a bad unit or if this is the way the camera is designed (I've started leaning towards the latter...)

Kit_L I am very curious of your findings. I started a few threads on this and seem to be alone in the realization...until now :)

Frank
frank@fmstudio.com
 
I have bought the camera and must say that i am pleased with its audio performance. :)
The mic i use is a Audio Technica AT825.

However, the delay in the audio chain makes monitoring the audio with headphones poor. The audio in the headphones is out of phase with the audio that comes into the mic/surronding audio. Not a big deal, but annoying.

/Roger
 
frankmcma said:
Easy test - record set to mic inputs and then use no mics. I tested this way by bringing the clips into Logic Pro and striping out the audio track, listening and then examining. There is a level of noise..not sure what to call it..I've called it fuzz cause its not really a buzz. Some call it white noise or as you call it floor noise.
Click to expand...

All cameras pre-amps will have some noise/hiss. This is going to be normal. The floor level of this noise should be low enough that it will make no difference for any normal recording. For any critical recording applications, you should be using a separate digital audio recorder anyway.


frankmcma said:
This noise is most noticeable in the built in mic. Recording in a quiet room with the headphones set to the halfway mark, the floor noise is extremely noticeable. I was willing to give it a pass, thinking, well I am going to get a good shotgun mic anyway, until I started testing XLR mics and noticed the noise, while reduced, was still very much there, even when I unplugged the mics.
Click to expand...

Forget the built-in mic, it's useless for any half-serious work. The noise you hear with a mic in a quiet room is sometimes called room tone. All mics have this in varying degrees and with varying characteristics. I know the built-in mic has all sorts of issues well beyond just being noisy.

New prosumers beat the Canon XH-A1 to death on audio too when it first came out. You just have to realize that for really good audio, you need a good recorder, mixer and mics. However, all these current XLR input camcorders are actually pretty good.

I use the HMC-150 onboard sound to capture from a wireless mic. I get very good, low noise sound. I have been able to boost low levels in post a dramatic amount with no noise.
 
Jeff. I completely agree. The other reason you will perceive noise, is when there's a distance to the object that's making the noise and then the signal gets boosted. I always try to get the best signal from the pots being as low as possible.. with either better mike placement, or a better microphone to begin with.


You really see this with the prosumer little cameras that don't allow for any real audio control. They are fine when the object is up close and very "present" but it just sucks when it's at a distance.
 
OK; tested various combinations of both settings (gain, mic vs. line, audio monitoring level) and the same two mics (Sony medium-length shotgun, and Sony high-end radio mics; both with which I am familiar).

Workflow: recorded to SDHC card, transcoded into Apple Pro Res 422 (medium quality), and both channels checked via waveform and studio monitoring (KRKs, etc.).

Boy, am I glad I ran these tests; here are the results:

1. Input 1, mic, gain 0; same Input 2: absolutely no floor noise at all: perfectly flat wave form in FCP; and only mixer noise discernible in the studio.

2. Input 1, line, gain 0; Input 2, mic, gain 0: no noise

3. Input 1, mic, gain mid; Input 2, mic, gain mid: same result: no noise

4. Input 1, line, gain mid; Input 2, line, gain 0: no noise

5. Input 1, line, gain mid; Input 2, line, gain mid: no noise

6. Input 1, mic, gain mid-point (yielding ~ -12dB), Sony mic, cable A; Input 2, line, gain 0: some "floor" noise

7. Input 1, mic, gain mid-point, Sony mic, cable B; Input 2, line, gain 0: no "floor" noise

8. Input 1, mic, gain 3, (yielding ~ -12dB), Sony radio mic, ; Input 2, line, gain 0: no "floor" noise

Immediate conclusion: one dodgy XLR-XLR cable, cable A. What I have labelled "floor" noise in test 6 is a bad cable.

So, following this, I went back to the footage shot recently, to see if I could find the source of the "floor" noise I mentioned in the recent post—and I am embarrassed to report that it is the noise of a fan. The assistant had left a small fan on during some of the takes. The setup was I was voicing over during the takes, or performing on camera, and my operator (who was monitoring the audio from the camera audio source) completely missed the sound from fan being on. As luck would have it, these two clips were the ones I picked to listen to more closely in my update!

The camera itself, if connected with good cables (and careless folk have not left fans or air conditioners on!), will record very clean audio.

I have not used the on-camera microphone, so can't comment on that, except to say that Jeff's remarks above re. room tone are spot on, and the reason I asked Frank where he had recorded his test—unless you record in an anechoic chamber, all rooms have a characteristic tone, which is why all good sound recordists record a couple of minutes of "room atmos" for editing, to cover any edits or changes in mic orientation.

hth, kl
 
Hey I got a quesion about the audio setup. Whats the correct settings for using a rode ntg-1 shotgun mic? When I plug it into channel 1, turn the phantom power on, I only get audio in the left side, and channel 2 is just full of hiss, what am i doing wrong? Its not a cable problem, cause this same thing happens with any mic, and any cable. Help?
 
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