Using Zoom H4N or Sony TC-D5 ProII as preamp for Canon D5MII

[Pedanes Bol]

I will be video recording my sons' classical music performances tomorrow evening. Until recently, I used a stereo AT825 microphone directly attached to D5MII or attached to H4N via XLR and synched later in post. I got better results with the later but synching always takes time.

This time I am thinking of using H4N as preamp for D5MII. I performed a test recording a few days ago by attaching AT825 to H4N via XLR and also using a TRS-to-TRS cable to connect PHONE/LINE out of H4N to MIC input of D5MII. Initially, I was skeptical about this set up since the source audio coming from PHONE/LINE OUT of H4N is dependent on the VOLUME adjustment level. After tweaking the volume levels on H4N and REC levels on D5MII, I found that if I keep the PHONE/LINE OUT volume on H4N at 20/100 and REC level on D5MII at 40/100 I get very good audio in the video. In fact, by listening, I cannot tell any difference between the audio WAV file recorded in H4N and the AAC audio recorded in the MOV file. I believe this set up provides clean audio to D5MII.

I am now thinking of using TC-D5 PROII (portable professional cassette recorder from 1980s) as a preamp for D5MII. This recorder might have a better preamp and also has real RCA type LINE OUTs. The only disadvantage is portability, since it is larger and heavier. I haven't done a test yet.

My questions are:

1. Despite my subjectively good test results, I am still not sure if the setup I used to connect H4N to D5II is the correct way of doing it. Is it possible this setup may ruin the audio on my video or even my equipment?

2. Does the Sony TC-D5 PROII ( TC-D5 Pro 2 ) recorder have a better preamp than Zoom H4N? Is it worth to try it with D5MII?

I appreciate your help and comments, thank you.

[Steve House]

You run a real risk of overloading the camera's mic inputs using ANYTHING with a line output as a preamp and frankly I don't see the point. You're still sending your signal through the camera's noisy marginal mic preamps regardless and that cancels out any advantage to you might get with an external preamp. If you're going to the trouble of using the H4n in the first place, use its recording as your primary audio and treat the camera audio as a scratch track to aid in syncing and then to be discarded. The cassette recorder would be out of the question since the big drawback of analog tape is that it is almost impossible to maintain sync without elaborate measures. Compared to syncing the files from your Zoom, syncing a tape from the Sony will a major, perhaps insurmountable, headache.

[Jay Massengill]

There are many attenuating cables available to go between the H4n and a dSLR mic input, some cables also have a headphone jack split off to allow monitoring. That's what I would use in this case and record the same audio on both devices with less chance of over-driving the 5D MkII input and be able to monitor at the same time.
Sescom makes many cables for this, or you can make your own if you have the soldering skills and a schematic.

[Pedanes Bol]

Thank you for the replies. I think this is the attenuator cable you recommend which I found at BH.

http://www.bhphotovideo.com/c/product/750963-REG/Sescom_LN2MIC_ZMH4_MON_3_5mm_Line_to_Mic.html
Most people gave good reviews, a few had some noise problems, not sure if it was due to their set-up. I will probably order one but still thinking whether I really need it. I am able to attenuate the line-out signal simply by turning the volume adjustment down to 20/100.

Also, another question is what Steve raises. Since the final audio is captured by D5MII's 'marginal' preamp, does capturing audio with a quality preamp then sending to D5MII really help with the final quality of the audio? To my ear it sounds like it is as good as it is recorded in H4N. I agree synching audio in post gives the best results but it takes time.

In regard to cassette recorder, I was thinking to use it only as preamp, was not planning to use analog recording on a cassette.

This evening, I will use the system as I tested. I will let you know the results.

Thanks again.

[Steve House]

Originally Posted by Pedanes Bol

Thank you for the replies. I think this is the attenuator cable you recommend which I found at BH.

Sescom LN2MIC-ZMH4-MON Line Out to Camera Mic In LN2MIC-ZMH4-MON

Most people gave good reviews, a few had some noise problems, not sure if it was due to their set-up. I will probably order one but still thinking whether I really need it. I am able to attenuate the line-out signal simply by turning the volume adjustment down to 20/100.

Also, another question is what Steve raises. Since the final audio is captured by D5MII's 'marginal' preamp, does capturing audio with a quality preamp then sending to D5MII really help with the final quality of the audio? To my ear it sounds like it is as good as it is recorded in H4N. I agree synching audio in post gives the best results but it takes time.

In regard to cassette recorder, I was thinking to use it only as preamp, was not planning to use analog recording on a cassette.

This evening, I will use the system as I tested. I will let you know the results.

Thanks again.

When you say recording in the camera sounds as good as recording in the H4n, how are you monitoring? Are you listening on computer 'multimedia' speakers or do you have access to good quality studio monitors? It may be that your playback environment doesn't reveal flaws that are actually there.

[Pedanes Bol]

I am back from my sons's concert and I would say my recording adventure was a failure. There is occasional on-and-off interference noise in the audio of D5II files. This noise is similar to the ones described in the bad reviews of Sescom cable at BH website I posted above. I am fortunate to have the original WAV recordings of H4N which I can synch to video. Those don't have any noise at all. Now I believe in Steve, thank you for your advice. I will not use this method anymore, I will rather synch.

For your question regarding monitoring, yes I used Sony studio monitor headphones to listen to the files.

[Jay Massengill]

Can you post a short sample of the problem audio from the camera? How will you record audio on the camera for your next project as a guide for syncing? I'm glad you obtained good audio on the H4n this time, so I wouldn't call it a failure.

[Pedanes Bol]

Here is the link for sample D5II audio with noise from last night. The WAV file from H4N has no noise at all. I did not have this problem during my tests at home.

http://dl.dropbox.com/u/86774786/MVI_0903.m4a

For my next project, I will use the intrinsic mic of D5II or another stereo microphone as guide for syncing.

[Jay Massengill]

To me those noises sound like a poor connection due to either oxide or fingerprint oil buildup on the connector/cable contact points, or stress on the cable due to its own weight or not being secured to the camera base so a short stress-free loop of cable is plugged into the jack.

I would gently clean both ends of the cable with a soft cloth and then don't touch the conductors with bare fingers. The only way to clean the jacks is to clean the cable, plug it in, gently rotate it, unplug it and then clean the cable again. Do this a couple of times taking care not to use any more force than needed.

I don't think this camera's mic jack has plug-in power. If it does have plug-in power, this must be disabled in a menu, or if it can't be disabled you must use a cable or interface with blocking capacitors to prevent the plug-in power from causing noises if your device doesn't need plug-in power.

[Pedanes Bol]

I will clean the cable as you described. This is same TRS-to-TRS cable I used when I did testing at home which worked very well at that time. I don't know what the difference was when I did the actual recording.

I cannot find anywhere in the manual whether the MIC input jack of D5II has plug-in power or not. I suspect it might have some low voltage there, because, one day, the battery of my external condenser microphone totally ran out but I was still able to record somewhat low quality sound, I guess some kind of voltage (from D5IIs MIC jack?) was still driving the microphone. There is no mention of this in the manual. There is nothing in the menu to turn the power of the mic jack on or off as well. I will look into the capacitors you mentioned but I think I am more leaning towards recording with H4N and syncing during post from now on.

Thanks again.

[Bill Davis]

I'm afraid there's not really good way to do this.

The issue is that unless they've made a change to the firmware that allows manual recording levels and defeat of the Automatic Gain Control built into the H4n - it won't make a whole lot of difference what you put in front of the mic input.

It's that AGC that "pumps" the volume up during quiet passages.

Outboard units like the Studio One mixers tried using a pilot tone at a frequency that couldn't be heard to fake the AGC into thinking that there was always a signal present to keep the gain control from pumping - but thats NOT the same as having a clean noise floor to start with since that's going to affect the dynamic range of your recording for the worse.

It's MUCH better to just record to the card in the H4n and don't mess around with trying to capture usable audio on the 5DMkii unless you're just using it as a scratch track to replace later.

FWIW.

[Jon Fairhurst]

Bill, the Canon 5D2 firmware has had manual gain control for some time now. Magic Lantern offers additional quality as you can control both the analog and digital gain independently. Canon has the analog at full blast and limits the user to controlling the digital gain only. Using ML, one gets roughly a 9dB S/N improvement.

AGC is still available. (I generally record with AGC ON when I want a sync track for an external recording.) But manual is available out of the box as well.

[Pedanes Bol]

I think I have an explanation why I had noisy audio during concert recording and perfectly well audio during my tests at home. The only difference was the lens on D5II, which was a fixed 35 mm lens at home whereas 24-105 mm zoom lens with IS during live concert. I was using a monopod and the camera was slightly moving. I believe the IS motor caused the interference noise in audio. It did not interfere with H4n audio but only with D5II audio.

Anyone experienced anything like this? I have had the internal microphone picking up IS motor sound in the past, but nothing like this (electronic interference) before. In fact, I have used the same IS lens with the same microphone directly connected to D5II (no H4N in between) in the past without any interference problems.

Any comments? Do you think IS motor might be causing this interference in audio?

[Pedanes Bol]

BTW, I sync'd the audio from H4N and created a DVD of the recital, the audio sounds very good. I learned a lot from this forum, thanks for your help.

[Jay Massengill]

It is possible the IS is creating the interference. Can you substitute a different (length, shielding) mini-TRS to mini-TRS cable between the H4n and 5D MkII and retest with everything else the same?