Also, I suspect the limitation on AVCHD audio quality is subject to your camcorder's specs. Suggest using MediaInfo to get the audio specs of one of your AVCHD files.

...Jerry

Good question.

I'm not worried about ambient noise. The problem is frequency response. With the camera's internal mic (Pana TM300), the bass and high notes drop out so notes from the timpani and triangle are essentially missing. With the Sennheiser, these two parts come in but they're weak.

Should I invest in a better external mic or a different audio recording medium, or both?

Dave

Irregular frequency response is most likely due to the microphone and its acoustic environment. A good external mic should fix that.

It used to be said, however, so far as frequency response is concerned, that the weakest link in the audio chain is the loudspeakers and listening environment.

well, presumably the preamp-converter chain on most camcorders isn't where they're spending the money, so in an absolute sense, the audio quality may be poorer. But I'm thinking you'd need to be listening with really critical ears to pick up those differences unless its a pretty cheap cam. Are you sure your camera isn't applying a wind-cut or other other filter on the signal? Check the menu options.

"the bass and high notes drop out so notes from the timpani and triangle are essentially missing."

Commercial recorders (people) use lots of mics and mix the outputs so that they get the balance they want. If you are just using a remote mic (or stereo pair) don't expect to get the same results as you would with a more complex setup. This applies particularly to the triangle, but I would have thought the timpani would pose no problem.

(Many times I have seen during a TV broadcast that the cameraman does a close up of the triangle as it is tinkled, but I don't hear it. But then that is probably due to my hearing more than anything.)

What camera?
Is it recording AC3?
What audio bitrate is being recorded?
Can you upload a 30 sec. example somewhere?

With low cost video/audio equipment the most likely limiting factor is the quality of your microphone.

I am not a fan of the Sennheiser MKE 400 mic ( though I love Sennheiser's higher end gear ).

I am also not a fan of the Zoom H2 recorder, though there is a brand new version out Zoom H2n, which might produce much better sound. I am waiting to find a review on the H2n, as I can see this inexpensive recorder being useful in certain situations.

The Zoom H1 is actually quite a good little low cost recorder, though like most of the low-end gear, you will have to use some EQ post-processing to compensate for the limitations of the low cost microphones.

A good recorder with great built-in mics is the Sony PCM-D50, which costs about $440 at B&H Photo right now. The mics are better than anything else at this price point.

Higher than this, then you are in to professional XLR mics, mixers, and recorders, where you could easily spend a few thousand dollars just to buy a basic package.

My advice is to investigate the new Zoom H2n or the H1, and be prepared to do some EQ post processing to correct for limitations of their mics, or buy the Sony PCM-D50 which sounds great right out of the box.

"Commercial recorders (people) use lots of mics and mix the outputs so that they get the balance they want."

The last time I recorded a small orchestra, I used 8 microphones, and in post I wished for more.

The points about chasing CD quality and post processing are well taken. I'm going to quickly back off my ultimate goals. But I'd like to get the best result I can with a single cam, so I'm checking out the Sony recorder.

So, bear with me on a few more questions.

My Pana TM300 manual says "audio is recorded with the Dolby Digital 5.1 Creator". When I render from Vegas Pro, I use Dolby Digital AC-3 Pro for the audio stream and Main Concept MPEG-2 for video, then go into Architect to make a DVD. In terms of audio quality, are there any bottlenecks in this work flow or is it only up to the external mic or recorder?

The Sony recorder has an analog output. Can this output go directly into the camera external mic input without losing quality, or should the audio be recorded within the Sony recorder (Wav format) and then synched with the video in Vegas? Is synching a problem?

Thanks,

Dave

5.1 to stereo? The following might be a good read for you. Audio: 5.1 vs Stereo Pay particular attention to the references to earlier threads on DVDA anomalies.

...Jerry

Definitely record in-camera using stereo, rather than using a consumer cam's pseudo-surround setup. This might explain the weird missing frequencies.

I'm confused as to whether you're expecting a bootleg orchestra recording to sound like a professionally produced CD, or whether you're experiencing unusually poor audio quality from your camera setup, and trying to fix that ??

>>>The Sony recorder has an analog output. Can this output go directly into the camera external mic input without losing quality, or should the audio be recorded within the Sony recorder (Wav format) and then synched with the video in Vegas?

For best quality, let the digital recorder record to WAV files.

>>>Is synching a problem?

You may have to adjust the audio track to match the video track with longer recordings. There is a very inexpensive audio editor called GoldWave ( $19 at www.goldwave.com ) that has a fantastic "TimeWarp" feature that enables you to adjust the time on an hour of audio to within a thousandth of a second. I use this feature all the time with long medical lecture videos that have an external audio track. ( Sound Forge sucks in comparison )

What I do is synch the audio and video at the start of the recording then make a cut, next synch the audio and video at the end of the recording and make a cut, and then figure out what the proper length of the audio should be to match the video, then export the cut audio track, adjust it's time in GoldWave, and then drop the new re-timed audio back in to Vegas. It sounds a little complicated, but it's very easy to do, and quite fast. I can synch an hour of footage in about 2-3 minutes of audio processing.

Sorry to rain on your parade!
Sennheiser MKE 400 is a stereo shotgun mic with a pretty awful frequency response and an even worse polar frequency response, full of lobes and inconsistencies, which is the common problem with all shotgun mic designs, leading to a comb-filer effect in the sound; it is designed predominantly for Speech.
Pro recording engineers would be using microphones each costing at least 10 times the cost of the MKE 400, with ruler-flat frequency response from 'DC to Light' and with consistent polar response, carefully positioned to balance the direct and indirect sound in a particular venue, likely determined from years of experience. They may use as few as 2, or as many as 40 or more.....

Thanks for all the good information. Now I know I came to the right forum.

What I record are performances by youth orchestras at Juilliard and other schools where my grandsons perform. I may have given the wrong impression that there are gaping holes in the frequency response, but it really isn't all that bad. The Sennheiser does a lot better than the cam internal mic, but based on comments here, I think I'll now try the Sony that was recommended. And I'll put some effort into audio processing and synching. Sounds like a challenge. The other thing I'll do is lower my expectations, because handling more than one recorder isn't in the cards.

Thanks,

Dave

"The other thing I'll do is lower my expectations, because handling more than one recorder isn't in the cards."

I use a separate audio recorder for these kinds of jobs and it is easier then trying to record in-camera. No leads run into the camera and as the audio recorder is recording 24/48 I can leave enough headroom to not have to worry about clipping.

As Christo has rightly said a good stereo mic in the right place will make the world of difference. I've been using the Rode NT4 which whilst certainly not top shelf does a pretty reasonable job. Getting it in the right place is an art but you'll generally not go too far wrong with it a few feet over the conductors head. Most venues that host orchestral performances have an XY microphone hanging in the right spot. If you're shooting in the one venue a lot maybe you can arrange to have one installed.

I feed the NT4 into my Edirol R-44, again not a top shelf recorder but as I do this kind of work for the love of it, good enough.

Orchestras make very complex sounds that do very interesting things acoustically. The best engineers in the world argue over the best way to record them but in general just one stereo mic in the right place can get a world class result. Futzing around with the sound in post is generally not needed.

The only addition I've found would be needed is if there's soloists, perhaps a separate mic for them would help to pull them out of the space. Next time I'll give one a try.

If you're handy with electronics for around $50 you can roll your own soundfield microphone, just Google that term. Using one of them does give you the ability to alter the sound in post.

Bob.