Question to Rode Procaster

I tried to experiment a little bit (checking the cable, with/without AC adpter, changing the room - same noise), and I figured out that when I increase the recording volume, the noise is louder and when I decrease recording volume the noise is quiter: above -12db the noise is very loud, at -12db its still very noticable, at -25db (or something like that) its almost unnoticable, at -40db there is no noise, but I dont hear anything at all :).
So that means the camera preamp is doing this?
 
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1) The Procaster clip appears to suffer from simple hum from a bad cable, connector, etc. Was the same cable used for both mics?

The other possibility is that since it is a dynamic mic, it is sensitive to magnetic fields where the NTG2 condenser mic is not. Have you tried moving the mic around to see if it is picking up an ambient magnetic field? Wall warts, fluorescent light ballasts, etc. power supplies can all be sources of this kind of interference. It appears to be a simple problem that can be determined with ordinary troubleshooting techniques.

2) Both samples contain traffic noise and short reflections from the room which makes it sound a bit "echoey" or "hollow". These problems can be eliminated by changing where/how the recordings are done. It doesn't necessarily involve spending any money on fancy gadgets. The solution could be as simple as closing doors and windows, moving to another room, or simply changing the direction the microphone is pointing, etc. Some people who need to do pro-quality recording in hotel rooms, etc, just hang bedding in the closet and record in there.

3) To my ear, I can't perceive any significant difference or advantage in the sound of the Procaster over the NTG2. Some voice recordings are deliberately made with shotgun mics because they prefer the sound. IMHO, I wouldn't spend the $$$ on the Procaster because I can't hear any advantage for the $$$.
 
1) Yes, the same cable was used for both mics.
I tried to record in different places - still same noise.

2) Windows and doors in the room was closed... but I just ordered Portha-booth (maybe it will help).

3) I already spend $$$ on Procaster, so its too late :) But the sample was recorded with mic at the distance 20-15cm (8"-6") from the narrator. Today I tried to speak to the mic from the closer range (5cm / 2") as Rode recommend in the user guide - and the result is very nice warm tone (but maybe the NTG2 will have the same results in the closer range, I didnt try it yet). (And other Procaster's advantage is that it doesnt need batteries which I always forget to recharge :))
However, when I talk to the Procaster in close range, I can turn the recording volume down and that noise is less noticable, but its still there...
 
hellboy80 said:
1) Yes, the same cable was used for both mics.
I tried to record in different places - still same noise.
Click to expand...

Then it is possible that the Procaster is broken. Can you try it with a different cable and different equipment (a mixer, etc.)

hellboy80 said:
2) Windows and doors in the room was closed... but I just ordered Portha-booth (maybe it will help).
Click to expand...

The porta-booth may reduce the reflection problem (maybe), but it is unlikely to do anything about the traffic and ambient noise.
 
How are you actually connecting the mics to the HV20? Both the Procaster and the NTG-2 are balanced mono XLR connections - how are you adapting them to the HV20's 3.5mm unbalanced stereo mic input?
 
Richard Crowley said:
Then it is possible that the Procaster is broken. Can you try it with a different cable and different equipment (a mixer, etc.)
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I can try to buy a different cable (the cable I use is very long, maybe 10 meters, I think I have this cable (or something like this): http://cgi.ebay.co.uk/Warwick-Rock-...temQQimsxq20091111?IMSfp=TL091111187005r10115). Maybe I should mention again I also use Shure A96F transformer (for connecting XLR to 3.5mm input).


Richard Crowley said:
The porta-booth may reduce the reflection problem (maybe), but it is unlikely to do anything about the traffic and ambient noise.
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Yes, I know, but I'm combining the voiceover with background sound (which are movie trailers), so the ambient noise isn't noticable.

Steve House said:
How are you actually connecting the mics to the HV20? Both the Procaster and the NTG-2 are balanced mono XLR connections - how are you adapting them to the HV20's 3.5mm unbalanced stereo mic input?
Click to expand...

With this:
http://store.shure.com/store/shure/en_US/pd/productID.104215400
 
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hellboy80 said:
I can try to buy a different cable. Maybe I should mention again I also use Shure A96F transformer (for connecting XLR to 3.5mm input).
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Are you SURE you aren't picking up a magnetic field? Have you tried rotating the Procaster to see if the hum changes in different positions, etc? Both the dynamic microphone and the transformer are potentially susceptible to picking up ambient magnetic fields.

Not suggesting buying anything to do the debugging. Do you know anyone else who has some audio equipment? Can you take the mic somewhere and plug it into another system to see if it still hums?

You should not need a transformer to connect either of those microphones to a typical camcorder mic input. A simple adapter/cable should be all that is required. Something like this:
http://www.markertek.com/Cables-Con...apters/TecNec-Cables-Connectors/XVM-249.xhtml
or this http://www.infinitecables.com/pop/av_xlrf-3.5mm.htm
or this http://www.amazon.com/gp/product/B00009X45L
Or for those who want to make their own...
http://www.rcrowley.com/CamAdapt.htm
 
Richard Crowley said:
Are you SURE you aren't picking up a magnetic field? Have you tried rotating the Procaster to see if the hum changes in different positions, etc? Both the dynamic microphone and the transformer are potentially susceptible to picking up ambient magnetic fields.
Click to expand...

I tried to record in different rooms and in different positions - nothing changed.

Richard Crowley said:
Not suggesting buying anything to do the debugging. Do you know anyone else who has some audio equipment? Can you take the mic somewhere and plug it into another system to see if it still hums?
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Ufortunately, I dont know anybody with audio equipment. Maybe I could go in the shop where I bought the mic and try there another mic.

Richard Crowley said:
You should not need a transformer to connect either of those microphones to a typical camcorder mic input. A simple adapter/cable should be all that is required. Something like this:
http://www.markertek.com/Cables-Con...apters/TecNec-Cables-Connectors/XVM-249.xhtml
or this http://www.infinitecables.com/pop/av_xlrf-3.5mm.htm
or this http://www.amazon.com/gp/product/B00009X45L
Or for those who want to make their own...
http://www.rcrowley.com/CamAdapt.htm
Click to expand...
I bought that transformer because a few people here told me that a simple adapter/cable is worthless :) I'm using it for recording interviews too (when I need long cable).
 
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hellboy80 said:
Ufortunately, I dont know anybody with audio equipment. Maybe I could go in the shop where I bought the mic and try there another mic.
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If you bought it at a local shop, then definitely take it back there (along with your adapter transformer and camcorder) and let them see if they can determine where the problem is. At least they should be able to plug the mic into their equipment and confirm whether it is working properly.

hellboy80 said:
I bought that transformer because a few people here told me that a simple adapter/cable is worthless :) I'm using it for recording interviews too (when I need long cable).
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Transformers are traditionally used to "transform" between different impedances. But modern camcorder mic inputs are perfectly suitable for use with any modern low-impedance microphones. An impedance-matching transformer is NOT required. Another possible advantage of a transformer is to provide a balanced input so that you can reduce picking up interference from long mic lines (10s of meters or 100s of feet) I have used my simple adapters (made myself) with cables over 100 feet (30m).

Simple adapters are far from worthless. Many of us have been using them successfully for many years. In fact they have the advantage of lower cost, less mass, and the elimination of the sonic artifacts of the transformer. Very few microphones have transformers in them anymore because more modern circuits are superior.
 
Richard Crowley said:
Simple adapters are far from worthless.
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This is what somebody from dvxuser wrote me few month ago:

You need an XLR converter box. Your camera's 1/8" connection is wired for stereo, unbalanced audio. XLR mics are single-channel, balanced audio. Not only do you have to make those interconnect, your camera sends out a low-voltage power supply intended for cheap, consumer microphones. This power supply can create noise in other audio gear. The converter box does the impedance matching, and defeats the power supply. It also gives you better, tactile control over your signals.

.... the cable may "do the job" to some extent, but it doesn't give you external level control like the boxes do. Plus, the boxes usually have much better pre-amps than any consumer camcorder. And there have been phase cancellation issues with the cables as well.

I didnt have money for XLR converter box, so I bought that Shure transformer. I didnt think this expensive transformer will do more damage than inexpensive cable :(
 
hellboy80 said:
This is what somebody from dvxuser wrote me few month ago:

You need an XLR converter box. Your camera's 1/8" connection is wired for stereo, unbalanced audio. XLR mics are single-channel, balanced audio. Not only do you have to make those interconnect, your camera sends out a low-voltage power supply intended for cheap, consumer microphones. This power supply can create noise in other audio gear. The converter box does the impedance matching, and defeats the power supply. It also gives you better, tactile control over your signals.

.... the cable may "do the job" to some extent, but it doesn't give you external level control like the boxes do. Plus, the boxes usually have much better pre-amps than any consumer camcorder. And there have been phase cancellation issues with the cables as well.

I didnt have money for XLR converter box, so I bought that Shure transformer. I didnt think this expensive transformer will do more damage than inexpensive cable :(
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1) No, you do not "need an XLR converter box". I can prove that by the fact that I do not use them and the audio is as good as the microphone and the camera will allow.

2) You don't need an XLR converter box to simply adapt a mono microphone to the stereo mini-phone input jack. You can see from the diagrams on my website that is simply a matter of how the connector is wired.

3) You don't need an XLR converter box to block the DC "plug-in power" from some camcorders. A simple capacitor will do that (as you can see from the circuit diagrams on my web page.) And furthermore your HV-20 does not have this DC "plug-in power", so it is not even an issue in your case.

4) You don't need "impedance matching". The mic input circuit of all modern camcorders is well suited for modern low-impedance microphones.

4a) Transformers DO give you the benefit of rejecting common-mode interference in long balanced mic cables. But common-mode interference isn't nearly as common in typical short (3m, 10ft) mic lines.

5) Your cable and inline transformer provide no "better, tactile control over your signals". They provide no control at all.

6) Camcorders which have automatic level controls (which cannot be turned off) do not benefit from external "better, tactile control over your signals". Anything you do to the signal will be automatically be overridden by the automatic function of the camcorder.

7) It makes no difference whether you are using a $100000 external mic preamp. You are STILL going through the camcorder mic preamp. Unless you open up your camcorder and modify your it to bypass its mic preamp.

7a) Typical "XLR converter boxes" do NOT "usually have much better pre-amps than any consumer camcorder". SOME of them may be better, but typically, they are NOT significantly better by design or execution.

8) "Phase cancellation issues with the cables" makes no sense. Cables do not cause "phase cancellation" unless they are improperly wired or defective.

I have been working with audio for >45 years, and >35 years in video. There is A LOT of audio misinformation ("indy lore") going around in these forums. At least from what I have seen in the last few months since I discovered this web forum. Some professionals here have given up arguing with the people perpetually posting this misinformation. I design and build audio and video equipment, so I have the perspective of knowing HOW it works. Most of the people offering misinformation don't seem to know how it works or why the equipment behaves like it does.
 
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Ok, thanks for explanation.

So I need that transformer only when I'll need cable which is longer than 3m (10ft)...

If I get it right - using a mixer with quality preamps between the mic and the camera/recorder (as somebody here adviced me today) doesn't eliminate my problem.

I'll try to take the mic to the shop where I bought it and I'll see. I also try to connect it without the transformer. But what if the mic is not broken, what do you recommend? To buy a quality soundcard and try to record into computer? (I tried to record something few motth ago with some Sonny shotgun mic into my cheap integrated soundcard and the result was terrible - very noisy and quiet, so I think I cant use my present soundcard :)).
 
You need a transformer when you are trying to eliminate common-mode noise. Doesn't matter whether the cable is 1m or 1Km.

If an external preamp (of ANY quality) eliminates the hum, then it fixes your hum problem. But it does NOT require an external preamp (of ANY quality) to eliminate your hum problem.

If the mic is not broken then something else is broken and is causing the problem. There is no fundamental reason you should not be able to use that microphone with your camcorder, with or without an external preamp, and with or without a transformer.

The mic preamps typically built into computers are virtually all terrible. There may be exceptions to this rule, but I've never seen one. Recording to a computer is a case where an external preamp IS always a better idea.

Note that almost no portable (notebook, laptop, netbook) computers have line-level inputs. The typically used solution is an external USB audio interface. Something like an inexpensive Behringer UCA-202 is more than adequate for the kind of recording you are doing. But the UCA-202 has only line-level inputs and a mic preamp is required. There are other products that have decent mic preamps and even phantom power that will also plug into the USB port of any modern computer.

Because of that antique connector on the output side of your Shure transformer, I don't see how you can just take the transformer out of the circuit to conduct the experiment?
 
So if I want to record into the computer which has cheap soundcard, everything I need is a good mic preamp? I actually have a desktop computer, but my narrator has notebook.

Richard Crowley said:
Because of that antique connector on the output side of your Shure transformer, I don't see how you can just take the transformer out of the circuit to conduct the experiment?
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Its impossible for me :) I'll try one of these simple adapter/cables from your previous links...
 
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If you want to record to a computer with line-level analog inputs, then you need a mic preamp. But if you want to record to a notebook/portable computer (which likely does NOT have line-level inputs), then you need mic preamp plus an external sound gadget like the Behringer USB thing. Or one of those other gadgets that combines mic preamp and USB sound interface in one box. Behringer (and others) make mixers that include the USB interface to any computer. The Behringer XENYX 1204 is an example of a combined-function product. There are certainly others in the genre.

Please note that I am NOT suggesting that you go out and get another cable. You already have your Shure transformer adapter cable and it should (in theory, at least) work just fine with that microphone. There is no reason for you to spend any money in that direction. I only mentioned the simpler cables for others who are reading this. If a simple adapter cable adequately does the job, no reason to spend the money on an expensive transformer or box. Save the $$$ and spend it on something that makes a more noticeable difference in the final sound track mix.
 
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hellboy80 said:
That means mic preamp is not necessary?

This USB sound card has some kind of preamp and the price is not so high:
http://www.emu.com/products/product.asp?category=610&subcategory=611&product=15186
Maybe I could try to buy this one... or maybe that cable from your link.
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The mic preamp is built into the cable. Note that it does not provide phantom power for condenser mics, but it would work with your dynamic Procaster.

The Emu product is 2-3x higher price, and still only one mic channel. If I were going to spend the money on an external box USB audio interface, I would want at least two mic inputs. There are similar products with two mic inputs.
 
Simmilar question here. I'd like to use Procaster on my Mac for podcasting. Can I then just use cheap XLR->3.5mnm cable from eBay, plug in mic and on my Mac back (mic in)? Is that ok, without mic preamp? :undecided
 
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