View Full Version : Audio: no switch between line level / mic level?


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Christopher Go
September 12th, 2004, 05:45 PM
Here's what Jay Rose had to say about these early audio reports on the XL2:

Having only mic-level input isn't a drawback per se - it's possible to build very good mic preamps - but doesn't really tell us anything about about this particular camera.

In every camera I've tested that has both mic and line level in, the line level was considerably better in terms of noise, distortion, or both. However, IF Canon got their act together and built a high quality mic input on this camera, there'd definitely be a design/cost advantage to making it mic-only. You can always use an external pad for line-level signals.

Since camera manufacturers seldom publish meaningful specs (and I've never seen Canonn publish any), the only way to tell is with some objective tests.

Saw this on the DV forums, Audio section.

Greg Milneck
September 12th, 2004, 05:57 PM
<<<-I agree with you about both claims (hiss and noiseless)... the thing is, you've got to really test, not just slap on some headphones and make a declaration. The DVX100A has a very pronounced hiss on the headphone output, but that doesn't get recorded, it's a byproduct of them having boosted the output. But if someone didn't know that, and they just plugged in some phones to listen to the camrea, they'd say "whoa -- DVX audio's awful, what's with this hiss??!" -->>>

Guys,
If you read my original posts what I said was:

The headphones have a significant hiss, but the recorded signal has substantially less hiss. But the recording does have noise....though not nearly as bad as what you are monitoring.

I underrstand why, just as you stated Canon has boosted the output on the headphones....BUT as a professional product this should not be acceptable. Afterall the purpose of the headphones is to be sure you are getting great audio, not acceptable audio. It is hard to tell thru all this hiss.

Bill Pryor
September 12th, 2004, 07:23 PM
I think you just nailed it with the phrase "professional product." Canon sells the XL as a consumer product--just as Sony will sell their new HDV camera as a consumer product. Sony decided that consumers don't want XLRs, and Canon decided that consumers don't want line in to their XLRs.

I read a good article sometime last year about the difference between a consumer and a professional camera. The writer was talking about still cameras, but I think his rationale fits video cameras very well. Basically, he said you can do about 90 percent of what you usually need to do with a high end consumer camera, but it's that final 10 percent professionals often need that makes the gear cost a lot more.

Greg Milneck
September 12th, 2004, 08:03 PM
Well you are correct that the XL2 is produced by Canon's consumer division, but there is no doubt that Canon is marketing and selling this to professionals. I doubt you would find many "consumers" buying this product.

This is a quote from Canons web site:

>>Unprecedented image control coordination between two XL2 cameras, remote computer camera control and direct video recording to computer are just a part of the capabilities of the XL2. Never before has so much creative power been put in the hands of the film maker, video artist, and corporate and event videographer.<<

Aaron Koolen
September 12th, 2004, 11:01 PM
Well Canon have it sussed then don't they. They can blab on about how this is a pro camera, for professionals and then when pros go "Err canon, where is the line level in?" they can go, "Well this is produced by our consumer division, and consumers don't need that".

Come on, no way in hell is this meant to be a consumer camera.

Aaron

Bill Pryor
September 13th, 2004, 09:32 AM
They market it by their consumer division, just as Sony does their small 1/3" chip cameras. I thought it was interesting that when the PD150 first came out it had that audio hiss problem in the mic level inputs, but the DSR250 had no such problems. The 150 was made in a Sony consumer factory, while the 250 is made in a professional camera factory. (That info came from a large L.A. dealer who is a strong reputation for reliability and no B.S., so I assumed it was true, but I didn't get the info first hand from Sony.)

Sony invented this whole "prosumer" phenomenon with the VX1000. I really think they thought it was a high end consumer camera, and it was. But--real filmmakers started using the hell out of it, and eventually Sony put DV into their professional market in the form of DVCAM. I think the manufacturers will never consider the small 1/3" chip cameras to be fully professional and probably won't ever offer all the stuff you really need for that final 10 percent.

Don Palomaki
September 13th, 2004, 05:12 PM
There was a significant hiss problem with the VX2000/PD150 audio. After a few months of significant grips and lost sales, Sony modified the audio input design in the PD150 and offered a free correction to at least some PD150 owners. But VX2000 owners were out of luck. I believe the issue was solved by changing the mic preamp to a low noise model.

Like all makers, Canon designs camcorder for the market segment they are trying to reach. For the vast majority of XL-series users and prospective buyers, line level XLR was not an issue. For those for whom it is a buy / don't buy deciding issue, go with a different model and enjoy the design trade-offs it provides. In any case enjoy the cheese.

Barry Green
September 13th, 2004, 06:19 PM
As I remember, it, Sony didn't offer a free fix to anybody. They charged like $150 or $250 for the fix.

Charles McConathy, owner of ProMax, stood up and said "no way... anybody who bought a PD150 from us, we'll cover you... we'll pay for the fix so your camera works properly."

I don't know if anyone else got it fixed for free, but ProMax buyers did, only 'cause Charles McConathy volunteered to pay for the fixes out of his own pocket.

Peter Koller
December 18th, 2004, 03:56 PM
Guys I am glad I read this thread BEFORE I started spending any money.

You know, I was trying to compile a really nice low budget equipment including the XL2 with some fine audio.. mixer, mic, boom and so on. And then I read this thing has no XLR-Line In!

I mean even the XL1 had a switch for Mic/Line Levels! And for balanced/unbalanced I bought a Beachtek, back then.

What is a XLR input good if Canon markets this camera to indie filmmakers when every serious sound person works with a mixer that puts out line level? Where is the audio improvement over the XL1? That they attached the MA200 to the camera to fix that lousy shoulderpad?

I am really pissed off now, because I spent half the day putting all equipment together and then everything falls apart, because Canon didn't build in such a damn switch!

Peter

Chris Hurd
December 18th, 2004, 03:59 PM
Peter, it is an annoyance but I don't see how it would make or break a purchase decision. After all, there are work-arounds for this issue. I have yet to find "the perfect camera" from any manufacturer.

Peter Koller
December 18th, 2004, 04:42 PM
I know.. I just needed to let off a little steam.

I felt like when you are on the set in the middle of nowhere, everything and everybody is ready and then somebody says:

"Who? Me? I thought you were bringing the tapes?"

Cheers, Peter

PS: The workaround would be a Beachtek again, right? Or was something else conjured up in the meantime?

Bill Pryor
December 18th, 2004, 05:03 PM
Well, you could use the mic output of your mixer. Of course, then you're not using the line input of the camera, which might give a little cleaner sound. It seems to me that not having line input for the XLRs is a big mistake that nobody is willing to admit. There' s no logical reason for not doing it. However, if you really want the camera, I don't think it would be a deal-killer.

Peter Koller
December 18th, 2004, 05:15 PM
I had the Shure FP 24 or something similiar in mind, but this mixer seems to have line level output only. Do you know a mixer you could recommend to me? It's my first day looking for mixers.. ;-)

Cheers, Peter

Bill Pryor
December 18th, 2004, 05:26 PM
I've got the Shure FP33 and it has both line/mic level out, as do most mixers I've used. Check B&H or Markertek.

Peter Koller
December 18th, 2004, 05:32 PM
Sorry I was posting a little too fast, I had the BH site open when I typed this.

One final question. Since I already bought a beachtek for my XL1 years ago.. what would be better going from the mixer line level via RCA unbalanced and the beachtek or from the mixer mic level into the XL2's xlr inputs?

A mixer does have a preamplifier, right? Which might be better than the one in the XL2?

Sorry... TWO final questions ;-)

Bill Pryor
December 18th, 2004, 05:35 PM
It depends on the camera. My understanding is that by going through the mic inputs of the camera, you would be using its preamp, which would not be as good quality as going line in and using the mixer's preamp. I could be wrong, and there may not be all that much difference; however, sound guys have always wanted me to go line in on whatever camcorder I'm using.
You may want to also check out Sound Devices:

http://www.sounddevices.com/products/302master.htm

They make some mixers that are considered by some people I've worked with to be comparable to the Shure, maybe better. They're even smaller, and maybe just a little cheaper.

Tim Commeijne
December 29th, 2004, 03:59 AM
Owkey,

Here's what I do:

We all know that the XLR's on the XL2 are ONLY mic-level. So if I want to get the audio from my mixer (wich is a line-signal) to my XL2, I have to send it to the RCA connectors.
The mixer and camera are connected by an XLR cable but I attached an XLR to RCA cable at the camera, so I can connect the XLR cable comming from my mixer to the RCA's from the XL2.

Only there is one problem: This is only one mono XLR cable, so I only send audio to the "CH1-RCA"
At the audio controls you can switch from CH1 to CH1-CH2 when your using "rear" = the XLR-connectors. You can not do that when usig RCA-input. So the audio is only on CH1 or the left channel. You can ofcorse get that audio on both channels in postproduction, but thats a lot of work.

So what I'm gonna do: I ordered an Line to mic adapter to attache between my mixer an the XLR cable gooing to the camera.

So this way I can send an MIC level-signal to the rear XLR-connectors.

Conclusion: The XL2 schould've had a Line/mic switch.
Extra costs for us! :s

But all in all: this is an awesome cam!

Greets Tim

Bill Pryor
December 29th, 2004, 09:59 AM
The only thing I know to do is spend the extra money for a mixer that outputs both line and mic. I still think this is a major screwup in this camera's design.

Waldemar Winkler
December 30th, 2004, 12:20 PM
<<<-- Originally posted by Barry Goyette : Ok...so canon made a big screw-up. As a non-sound aficianado...I guess I want to know how big is it....

1. Is balanced input necessary for line level input ?(I understand why it is for mics...but I've run long unbalanced line level cables to my cams before with no harm that I was aware of.
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A balanced audio signal is designed to reduce contamination, or noise that might be picked up in a long cable runs. Dynamic microphones produce really low signal levels. Condenser mics have stronger signals due to their battery or phantom power. Still, an unbalanced cable run as low as 10 feet COULD pick up enough stray electrical noise from AC, radio waves, cell phones, and whatever else happenes to be in the air to significantly contaminate the signal. In a balanced system, the audio signal is split between two wires in a three-wire cable, and the phasing of one of the signals is inverted 180 degrees. At mixer or camera connection, the out-of-phase signal is inverted back in-phase with the untouched signal. Any noise that has been collected is inverted as well. The result is the picked up noise is effectively cancelled, and the original audio signal is passed on for processing. Additionally, the third wire in the cable completely surrounds the signal carrying cables in a wire or foil wrap. This "shield" further blocks any miscellaneous radio frequency from invading the signal carrying wires.

Balanced audio signals are usually very low impedance, 600 ohms or less, but they don't have to be.

An unbalanced audio may or may not have the shielding metal wrap. Unbalanced lines carry much stronger signal levels, and much greater resistance. They are best used for short cable runs.
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2. aren't most mixers capable of outputing mic level as well as line level?

Yes, most mixers are capable of outoutting both balanced and unbalanced signals. Those that have XLR connection for output usually do, but it is always good to check the specs. The better mixers have a switch for selecting low or high impedance on the XLR connection. Mixers that use 1/4" connections could also be used for balanced signals, but generally are not.
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3. is an inline line-to-mic reducer (adapter, transducer or transformer...whatever you sound geeks call it) a possibility? available?

Yes, in line reducer/attenuaters are very common. The most popular are XLR to 1/4", but they can be any combination. What is important is a small internal transformer that, depending upon the direction of the signal travel, is a fixed step-down or step-up in impedence. Another approach is a direct box. These come in all kinds of configurations. Some are passive, some are battery powered. The common goal is to reduce an incoming signal to a low impedance balanced output. The one I use is made by Pro-Co. On the IN side are 1/4", 1/8" Mini-plug, and RCA connections, as well as a sensitivity switch for instrument, line, and speaker. On the OUT side is XLR, 1/4", and a ground lift switch, in case the source of contamination is coming from earth ground. Visit your local professional music store an take a look at what they have to offer.

TingSern Wong
January 1st, 2005, 09:58 PM
To solve this problem is simple - just grab a PSC (Professional Sound Co-operation) LINE to MIC PAD ... plug the rods into the Canon XL2 mic XLR input, and your LINE IN XLR cable into the rods. Presto - it is done. No need to wait for Canon's XL2 version 2 :-). And you have best of both worlds - mic level sensitivity for XLR and LINE IN if you needed it - all via XLR input.

TS

Waldemar Winkler
January 2nd, 2005, 10:25 AM
<<<-- Originally posted by TingSern Wong : To solve this problem is simple - just grab a PSC (Professional Sound Co-operation) LINE to MIC PAD ... plug the rods into the Canon XL2 mic XLR input, and your LINE IN XLR cable into the rods. Presto - it is done. No need to wait for Canon's XL2 version 2 :-). And you have best of both worlds - mic level sensitivity for XLR and LINE IN if you needed it - all via XLR input.

TS -->>>

Definitely another approach. One of these will take the guesswork out of the equation. Only about $30US at B&H. You will need one for each input.

Indeed, it would be well worth the time to browse through the "adapters, cables, and cable accessories" section of your favorite electronic dealer's catalog or website. Lots of neat and reasonably priced toys/problem solvers.

Bill Pryor
January 2nd, 2005, 10:26 AM
But you're still using the camera's preamp, which defeats the purpose of line level in.

Waldemar Winkler
January 2nd, 2005, 12:55 PM
<<<-- Originally posted by Bill Pryor : But you're still using the camera's preamp, which defeats the purpose of line level in. -->>>

What? Any incoming signal, whether it be hi-Zor L-Z will be affected by the camera's pre-amp. I believe that to be is a non-issue. I have been referring to devices that step an incoming Hi-Z signal down to a Lo-Z signal, which then allow the camera's audio system to function as designed.

Can you clarify what you mean?

Don Palomaki
January 2nd, 2005, 04:55 PM
If the issue is noise, most field recording venues will have higher noise floors than the XL1 mic preamps.

However, for those critical situations where one needs the best S/N and does not want to lug about a separate, dedicated sound recorder pad the line input signal down to around -35 dBV, and use the MIC ATT setting. This reduces the gain of the front end preamp (which generally sets noise level) and will net a significantly better noise floor than using full MIC sensitivity setting.

Greg Boston
January 2nd, 2005, 11:28 PM
Too bad Canon won't make the now defunct 'film grain' switch into an XLR line/mic level switch.

Are ya listening Canon? Here's what you can do with your new, unused switch.

Just dreaming....

=gb=

TingSern Wong
January 3rd, 2005, 01:27 AM
Hi Don,

Mic ATT setting on XL2 won't work for a LINE IN voltage coming from a standard FPM (Field Mixer). Signal levels are still way too high. You really need a MIC to LINE IN pad. I tested it myself before I committed to purchasing dual PSC pads. Now a very happy user.

TS

Don Palomaki
January 3rd, 2005, 04:44 AM
That is what I said - pad the input signal down to -35 dBV. For a +4 dB line level, that would call for a nominal 40 dB pad.

Bill Edmunds
January 17th, 2005, 09:14 AM
I know Canon is releasing new XL2's without the film grain effect... is there any chance they also fixed this mic/line issue as well?

Chris Hurd
January 17th, 2005, 09:20 AM
No. There is no chance of that.

Bill Edmunds
January 17th, 2005, 09:26 AM
<<<-- Originally posted by Chris Hurd : No. There is no chance of that. -->>>
Wow. That's a major disappointment. I still can't believe they would forget such a basic component of professional video. Sometimes Canon just puzzles me.