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Old July 8th, 2005, 12:02 PM   #1
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Soundboard Cables

As I said in my intro post, most of your threads/topics have been over my head. I'm unemployed and being forced to make some money from my video and graphics hobbies (which is kind of fun, so I'm not complaining). But my goal is to improve and I'm starting at the bottom.

I chose not to use the soundboard at my last project (ballet recital). The built in Mic on my GL1 did a terrible job. I was embarrassed, so I bought the Rode Video Mic and I'm looking forward to working with it. However, I would like to buy cables for the soundboard.

I saw three from Hosa. All were 3.5 Mini to 1/4". But they had different balance/unbalance specs.

My question is: Do I need all three? If so, when do I know which to use?
Thanks,
Scott
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Old July 8th, 2005, 01:32 PM   #2
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Quote:
Originally Posted by Scott Routt
As I said in my intro post, most of your threads/topics have been over my head. I'm unemployed and being forced to make some money from my video and graphics hobbies (which is kind of fun, so I'm not complaining). But my goal is to improve and I'm starting at the bottom.

I chose not to use the soundboard at my last project (ballet recital). The built in Mic on my GL1 did a terrible job. I was embarrassed, so I bought the Rode Video Mic and I'm looking forward to working with it. However, I would like to buy cables for the soundboard.

I saw three from Hosa. All were 3.5 Mini to 1/4". But they had different balance/unbalance specs.

My question is: Do I need all three? If so, when do I know which to use?
Thanks,
Scott
As to how many to buy, how generic do you want your kit - just to match this one installation or something you could use in a variety of locations? According to what I read, the GL1 mic input is rated at -55dB stereo unbalanced. You'll need to see what the soundboard that you want to connect to is putting out and attentuate accordingly. First off is the mixer output you're tieing into stereo or mono? Balanced or unbalanced? Pro +4dBU or prosumer -10dBv line level?
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Old July 8th, 2005, 02:12 PM   #3
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Thanks Steve, but that was what I was talking about when I said most of this is over my head. But from what I gleaned, the camera remains the same, the board is the variable, and I need all three for whatever situation arises.

Since I didn't understand the answer, will I be able to tell what cable works best by trial and error and monitoring the sound with head phones? Or will any problems or successes only become apparent when I go to edit the tape in FCP?

Thanks,
Scott
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Old July 8th, 2005, 04:36 PM   #4
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Quote:
Originally Posted by Scott Routt
Thanks Steve, but that was what I was talking about when I said most of this is over my head. But from what I gleaned, the camera remains the same, the board is the variable, and I need all three for whatever situation arises.

Since I didn't understand the answer, will I be able to tell what cable works best by trial and error and monitoring the sound with head phones? Or will any problems or successes only become apparent when I go to edit the tape in FCP?

Thanks,
Scott
Well, monitoring with headphones is defnintely a good practice in any case <g>. As for the rest ... an excellent book would be either "Producing Great Sound for Digital Video" and/or "Audio Postproduction for Digital Video" both by Jay Rose. You don't need a degree in engineering but acquiring a little knowledge of decibels and such would be very helpful and either of those two books are very readable introductions.

Not knowing what you already know it's hard to answer you better so forgive me if I bore you with basics you already know. Essentially the strength of sound and the electrical signals representing it are measured in decibels or dB. Each 3dB means about twice as loud or conversely -3dB means half as loud. Electrical circuits are designed to operate within a certain range and they work best when their inputs see signals with a certain range of levels determined by their designers and they also will send their outputs at some specific design level. Mixers and such send their signals at fairly high levels called line level (and to keep us on our toes, the "line level" of professional gear is standardized at about 12dB stronger than the "line level" of consumer gear like our cameras.) Microphones, on the other hand, usually produce much weaker signals than that and the inputs designed for them are usually very sensitive. If you take a microphone and plug it into an input that expects a line level signal, like a power amplifier, it will be very very faint if audible at all. OTOH, if you send a line level signal into an input designed for a microphone it will be so much stronger than the intended input level that it will overload the circuits and generate a lot of noise and distortion. So the trick is to put some attenuation called "pads" into the line between the two to drop the mixer's output down to what the camera is designed to accept. Mixers will output one of two different standard line levels, either a standard pro line level or a consumer level which is about 12 db lower, while your camera wants to get a much weaker mic level at about -55db. If the mixer put out the pro line level you need to drop it by a total of about 57dB while if it puts out the lower consumer line level you need to drop it by about 45dB. (The pro is labeled +4dBU while the consumer is labeled -10dBV. Because a "dBU" and a "dBV" are slightly different, +4 and -10 are actually a little less than 12dBV apart. Ain't that weird?)

A second factor to consider is the nature of the cable and its connections. Unbalanced circuits send the signal down on one wire, the "signal" wire, and return it on a second ground path that also usually serves double duty as the shield in an audio cable. An unbalanced stereo cable has two signal wires, left and right, and a single shared return usually through the shield. Balanced, otoh, has one signal split into two, one-half the pair is inverted, and then they are sent simultaneously out on two wires, called "hot" and "cold" with a third wire for the ground and shield. At the other end, the hot and cold are recombined into one signal again. Special circuits in the devices at each end take care of the balancing and unbalancing act. The exact technical meaning of all that isn't so important as it is understand that a balanced output and cable and an unbalanced input can't just be plugged into each other and expected to work properly. (Okay, well sometimes you can get away with it.) A simple adapter would connect the balanced "hot" wire to the unbalanced signal wire, the balanced shield to the unbalanced shield/ground, and the balanced "cold" wire is either left unused or bridged over to the unbalanced ground also. An unbalanced stereo cable and connector has two wires carrying two different L & R signals and a single ground. A balanced cable and connector ALSO has two wires and a ground but it carries ONE MONO signal split into two halves and combined again at the destination end. The plugs at the ends of the two cables might look exactly the same and in fact they both might be wired exactly the same and you could interchange them. A patch cord with a 1/4" TRS plug wired straight through to another 1/4" TRS plug tip-to-tip, ring-to-ring, and shield-to-shield could be used to carry a balanced mono signal, a single unbalanced mono signal, or two unbalanced stereo signals. It's the circuits it's plugged into at each end that make all the difference in the world.

In our case, the GL1 expects a simple unbalanced signal at the mike input (actually two of them if you plan to record in stereo) and doesn't have the necessary circuits to accept a balanced signal properly - it's up to us to provide the conversion if we're feeding the camera from a balanced source. At the same time we need to reduce the high line level signal from the mixer down to the much weaker level the camera expects. The manual says the camera sensitivity is -55db. That means if the mixer is putting out the consumer -10db line level, we have to subtract another 45dB to match it right. If it's putting out the professional line level which is about 12 db stronger than the consumer standard, we have to lose more like 57dB. If the mixer output is unbalanced we don't have to worry about that part of the equation because the camera is too. Some mixers are balanced only, some are switchable depending on how the cable plugged into it is wired, and some actually have both separate balanced and unbalanced outputs to choose from. Since the camera is unbalanced, if the mixer output is also unbalanced we're done when we've got the levels matched up. If it's a balanced output we have to unbalance it as well. That simple unbalancing connection I described in the above paragraph loses about 6db all by itself so if we were connecting a single balanced professional mixer output to just one channel of the mic input on the camera, we'd need to have about a -50dB pad in the line - that plus the -6dB loss in the balanced/unbalanced adapter itself gets the two signals close enough together for government work. The camera actually has an I think -30dB pad built in that you can switch on from the menu so that can account for part of the required drop if you wish to use it.

The only way to know for sure what adapter to use and how much pad to use is to look up the specs for that specific mixer brand and model.

The camera mic input expects a stereo mic, a two'fer, so its plug is a stereo mini plug carrying both left and right channels with unbalanced connections. The mixer probably provides two separate outputs, one for each each channel. If you want to record in stereo and if the mixer outputs are unbalanced you need to connect them through the required pads to a "Y" dual-mono-to-stereo adapter at the camera end to feed both left and right mic inputs. If they're balanced, you need to feed them both through a pad in each line to an unbalancing adapter for each one and then from there to the "Y" that plugs into the camera.

I don't know what adapters you've been looking at so I can't make specific recommendations. Hosa makes a ton of different adapters. One thing is for certain - don't try to use a 1/4" TRS to 3.5mm stereo mini-plug adapter from a balanced mono out on the mixer to the camera's mic input. You could end up with a strange situation where the same signal is recorded equally on the camera's left and right channels but 180 degrees out of phase. When you play it back in your editor if you listen to just the left or right channel you'll hear it fine, if you play it in stereo you'll hear it but it'll sound out of kilter, and if you try to play back both channels together in mono like many TVs would do they'll cancel each other out and you'll get silence.

Those books I mentioned have some good diagrams that makes this all easy to follow.

Last edited by Steve House; July 8th, 2005 at 05:12 PM. Reason: typo correction
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Old July 8th, 2005, 06:20 PM   #5
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Scott:

First figure out which audio you want to record. You probably want a mix of ambience (with audience clapping, and reverb) and the feed from the sound board.
You can go with only the sound from their board, but it will not have any reverb on it (which can be wierd).

Suppose you want a feed from the board and ambience.
You should use a seperate recorder for the sound, that would be easiest. Put it by their audio board, and get a feed from it (befriend the audio person). A lot of recorders will take +4dBu or -10dbV line-level inputs, which makes your life easier.

Example recorders:
DAT (i.e. Tascam) - only thing you have to worry about is digitizing the DAT. It should have a digital output for lossless transfer.
laptop with audio interface - records a long time, can record multiple tracks depending on audio interface. If you own a laptop, this can be a good route.
compact flash recorder (i.e. marantz, sound devices)
mini-disc - consumer units have a bunch of catches to them.
I'd look at possibly renting one. Unfortunately I can't say which option would be the best for you. You're looking at things like whether or not you can rent it, how you're going to get the audio into your editing system, cost, and ease of use.

Sync: You'll have to sync the two up, but this isn't a big deal. Having a sync point will make life easier... a slate with a clapper will give you a visual and audio cue. If they have a mic hooked up to their board, then do that. If that isn't possible, it's not a big deal through audio.
When shooting, don't start/stop the tape so you only have to sync once.
Some recorders will drift 1 frame every half hour or so in relation to video, so that's something to watch out for. You'll need to sync the beginning and end, and stretch the audio (don't pitch shift).

Setting levels: Make sure you don't clip. Some recorders have limiters which kind of help prevent that (you get distortion instead of digital clipping).


Other options:
A- You could buy/rent a Beachtek or similar XLR adapter. I think you're looking for a model that accepts mini-plug and XLR.
In one channel, you record a feed from the board.
In the other channel, use a microphone to record ambience.
In post just center both channels.
Stereo honestly makes little difference because most people's systems aren't setup to do it. One advantage of this is that you get to monitor all your sources, and it can be easier.
Get a big roll of gaffer tape to tape down a long XLR cable. I've bought gaffer tape on eBay for $5USD on eBay + shipping. Otherwise it's like $12-20+shipping. Gaffer tape doesn't leave gunk behind... it's a nicer on the venue.


B- You could get an adapter to take the board feed (and even the miniplug input).
Caveats:
The adapter needs a DC blocking capacitor to block out "mic plug-in power" that most camcorder mic jacks put out. That power will cause hum/buzz in your audio.
The adapter needs to bring levels down to what the camera likes. I'd probably use a mixer to do this, because you don't know what level they're going to send from their feed. Plus, it takes balanced signals.

You might as well just get a Beachtek?
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Old July 10th, 2005, 02:04 PM   #6
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Steve's Mixer Advice

Thanks Steve, I ordered "Great Sound" today from Amazon. I read all the reviews and "Great Sound" seemed like the one to start with. I've been reading your very long post over and over trying to translate it (You really went all out- thanks). So each 3DB or -3DB means twice or half as loud. Thanks. I'm grasping what you said about the expectation difference between equipment (Mic to amplifier vs. Mixer to Camera's mic jack). I grasp the need for attenuator (mixer to camera).

You said a mixer will output one of two different standard line levels (pro or consumer line level) and that consumer level is about 12dB lower than Pro Level. You also said my GL1 expects to received a -55dB signal. You said I could expect to receive a consumer level of about -10dB requiring me to turn it down by -45db. And I could expect a pro level of about 12 db, requiring me to turn it down 12 more than 45 or -57dB. (Am I following you correctly?)

After reading your description of the mixer and its output settings and the difference between Pro and Consumer Level, my first question concerns the mixer.

Are you talking about 1 mixer that outputs both levels? Or are you talking about two different mixers, one that does Pro and another that does consumer?

I noted what you said about the different labeling for Pro and Consumer (dBU vs. dBV).

You said the second factor is the nature of the cable and its connections. Thanks to your description, I can now visual the difference between balanced and unbalanced cables. An unbalanced carries left/right signals on two different wires and a balanced cable carries these signals on one wire. The destination device deals with the balancing/unbalancing act.

You said my GL1 expects to receive an unbalanced signal either mono or stereo. I must help convert the signal to unbalanced if it arrives from a balanced source, while reducing the strong originating line level.

You said a soundboard could come with several options or none and that I might have to research the equipment to tell if its signal will be balanced or unbalanced. Assuming I make the determination. Would I do it as follows?

Without a mixer:
Balanced Soundboard: Use balanced to unbalanced mini into the camera.
Unbalanced Soundboard: Use Unblanced to unblanced mini into the camera.
Hope for the best because my signal will be too strong without a mixer.

With a mixer:
If the mixer has unbalanced outlets, I use a Y cable with the mini to the camera and the other 2 ends into the mixer. Is this Y cable balanced or unbalanced? Does it matter? What kind of end plugs into a mixer? Is it XLR (heard of it/never seen it)?

If the mixer has balanced outlets, I use the same as above. However I need to use a converter to unbalance the signal. This converter plugs into the mixer and the Y cable plugs into converter's other end.

Even if I'm right or close on the above connection between camera and mixer, I'm not visualizing the connection between soundboard and mixer. Is it similar? If the soundboard is balance or unbalanced connect it accordingly so that the signal enters the mixer as unbalanced?

You said:
"The camera actually has a -30dB pad built in that you can switch on from the menu so that can account for part of the required drop if you wish to use it."

What do you mean by that? I see where i can turn the Attenuator on or off. When I turn it on, the volume records noticeably softer.

Thanks Steve. I'm really trying and I appreciate all the effort you put into that last answer.
-Scott
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Old July 10th, 2005, 02:06 PM   #7
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Glenn's Beachtek thoughts

Hey Glenn,
Your 1st paragraph nailed my motivations.

" First figure out which audio you want to record. You probably want a mix of ambience (with audience clapping, and reverb) and the feed from the soundboard. You can go with only the sound from their board, but it will not have any reverb on it (which can be wierd)."

So yes, that's what I want to achieve.

You mentioned using sound recorders and listed several kinds with some advantages and disadvantages. I think ease of use and cost would be more important factors to me at this stage in the game versus quality.

Would compact flash be viable? If so, what should I look for in terms of brands/models/size? Do they record as MP3 or Aif? Would I be able to hear it through headphones as it played? Would I need to run it through a mixer before sending the sound to the compact flash? Or would I download it straight to Itunes from the compact flash?

Syncing: Yes I made the stop/start/stop/start mistake the last time so I couldn't even use my borrowed 2nd camera's audio or visual. I see what you mean here and will learn from that mistake. I just did a practice test filming a Kid Rock song with my camera and Rode Video Mic and captured it into FCP3. I think put the aif file from CD under it and synced it together and was please with the results. However, I'm wondering if I'm doing it the right way. I'm trying to determine where the film sound track and the CD audio track start using the time line and then using the razor at my guess point. Should I be doing the syncing somewhere else like in the viewer?

At the end, you said that it sounds like I need to bite the bullet and get a Beachtek. Maybe you're right. However, is a Beachtek a mixer or it different?

Can you wade through my drabble and point me in the right direction if I can express what it is I'd like to do.

As of today, I own one GL1, one Rode Video Mic, one Tripod, and one Mac G4 with FCP3. I've ordered some 10 foot line cables and a set of head phones. I want to concentrate on weddings. With this in mind, I know I need some additional equipment.

I was thinking about getting a cheap Mini DV camera for use as a second camera and to use for capturing tape so I don't wear out the GL1.

I think the GL1 and Rode Mic will take me anywhere I want to go at a reception as long as I have a shoulder unit for the camera.

I think I need some strategy for equipment buying to handle the ceremony. I'm thinking that I would need two wireless mics for the couple. This gets confusing, because I've heard of the preacher wearing the church's wireless mic and they're being feed back from the video man's wireless mics. Something to be concerned with, perhaps? Or should a wireless shotgun mic be set up behind the altar? I don't know, I'm just imagining here.

Where do the wireless mic signals go? Do they go to a Beachtek? Is a Beachtek also a mixer? Does the Beachtek need to hooked up to a camera? Or does it have some kind of hard drive?

You see where I'm heading. I have a desire, but I do not have a clue? I almost feel that at this point, I need some direction on what kind of equipment to get and then I need to spend the time to learn how to use that equipment. So what kind of equipment should I focus on if I have a $5,000 budget?

Thanks a bunch,
Scott
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Old July 10th, 2005, 03:18 PM   #8
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A wedding is a different scenario from a ballet recital.

The two most popular ways of capturing the wedding vows:

Both involve putting a lav on the groom or ?officiant?. Ideally you would do both of them I'm guessing.

A- Record to a portable recorder, which stays on the groom or officiant. mini-disc, iRiver are two of the most popular choices.
The lav will need to work with that recorder.
mini-disc: upload limitations, but not as much of a problem with the new hiMD units. hiMD can upload only once unless you hack it. As far as I know.
You'll need to set levels and make sure the groom/officiant doesn't mess with the recorder.

B- Use a wireless transmitter/receiver, and record into your camera.
The good wireless systems use XLR, so you may want a beachtek for your camera.
Downsides: Wireless consumes a lot of batteries, and is kinda expensive when you consider the capital and recurring costs from batteries. For weddings you aren't using too many batteries compared to shooting narrative/drama.
Wireless is prone to dropouts/interference.

A popular recommendation is for the Sennheiser G2 system (which uses cheap AA batteries). There are other recommendations for cheaper systems.
Price correlates with audio quality (not a big deal here) and reliability against dropouts/interference.

I don't have any experience shooting weddings so I can't give you the ins and outs of using either method.


For all the other audio (i.e. reception), the Rode Videomic should be fine.

2-
Quote:
At the end, you said that it sounds like I need to bite the bullet and get a Beachtek. Maybe you're right. However, is a Beachtek a mixer or it different?
The Beachtek is an adapter box for XLR --> mini. It handles the unbalancing of the audio and blocking mic plug-in power. It also has volume controls, but from what I hear the changes happens in "steps" and not smoothly like a mixer.
Some of the models have features like:
phantom power for microphones that need it
limiters - you get distortion instead of clipping. Mild limiting is impossible to hear. Effectively you get a little more headroom.
preamps (DXA8)- can give you better S/N ratio by using the better Beachtek preamps instead of your camera's.
With certain cameras, the DXA10 may be better because it outputs consumer line-level signals. Some cameras can take line-level in.

Quote:
Syncing: Yes I made the stop/start/stop/start mistake the last time so I couldn't even use my borrowed 2nd camera's audio or visual. I see what you mean here and will learn from that mistake. I just did a practice test filming a Kid Rock song with my camera and Rode Video Mic and captured it into FCP3. I think put the aif file from CD under it and synced it together and was please with the results. However, I'm wondering if I'm doing it the right way. I'm trying to determine where the film sound track and the CD audio track start using the time line and then using the razor at my guess point. Should I be doing the syncing somewhere else like in the viewer?
In FCP, scrub through the footage and put a marker on the sync point.
In the viewer, the marker will end up in the clip.
In the timeline, select the clip first and then hit "m" when the playhead is on the sync point.

Do this for all sources.

Click on the area above the marker and slide it left/right to the right position. turn snapping on (hotkey: n) to get the markers to snap.
If you click anywhere else on the clip, the markers inside won't be snap points.

Sync points:
Visual cues: Slate/clapper when the two meet; any object hitting the ground: there will be a corresponding audio spike; plosives in dialog b's and p's there's silence when the speaker's lips are closed, and then sound when the lips open; drum stick hitting a drum
If syncing video to video, bring a flash along and just sync to that.
Through audio: Turn waveforms on in sequence settings. Look for a spike you can match up.
With some audio sources that may be harder. A lot of CDs mastered nowadays have excessive compression so the waveform looks like a big rectangle.

Quote:
This gets confusing, because I've heard of the preacher wearing the church's wireless mic and they're being feed back from the video man's wireless mics.
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Old July 10th, 2005, 06:19 PM   #9
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Quote:
Originally Posted by Scott Routt
Thanks Steve, I ordered "Great Sound" today from Amazon. ....
See comments embedded
..
Quote:
After reading your description of the mixer and its output settings and the difference between Pro and Consumer Level, my first question concerns the mixer.

Are you talking about 1 mixer that outputs both levels? Or are you talking about two different mixers, one that does Pro and another that does consumer?
Yes, No, and Maybe LOL - some mixers are pro level only, some are prosumer only, some have two sets of outputs with a set at each level, and others are selectable with switches or by software. It depends on the brand and model. Some also have a both balanced and unbalanced outputs - the so-called "tape out" outputs are frequently a pair of L/R unbalanced RCA jacks like the red and white jacks on the back of your VCR and carry the same signal as the balanced XLR connector "main outs."

Quote:
....I can now visual the difference between balanced and unbalanced cables. An unbalanced carries left/right signals on two different wires and a balanced cable carries these signals on one wire.
Not quite. Both cables have two signal wires and a shield for a total of three conductors. The balanced connection carries one mono signal using the two wires (called "hot" and "cold") and the shield in sort of an electronic menage-au-trois <g>. A stereo connection also has the same two wires and shield, it's an identical cable and even the connector's can be the same as well, but its connections carry *2* different mono signals to make the stereo, the left channel carried between one wire and the shield and the right channel between the other wire and the shield, both channels sharing the shield as a common return path.

An unbalanced MONO cable, like each of the left and right paired cables on your stereo, has a single wire and the shield to carry the one signal.


Quote:
Would I do it as follows? ...
The soundboard IS a mixer so I wasn't necessarily thinking about you adding a second one in the line to your camera although that certainly could be done and it would give you more control over what's feeding the camera.


Quote:
Without a mixer: ...
With or without...

Look carefully at the miniplug on the end of your headphones cable. See how it's divided into three segments? There's the tip, then there's a little insulating ring, another short length of metal, another little insulating ring, and then the majority of the length of the plug. The end is called the "tip" (surprise!) the next bit of metal is called the "ring", and the longest part is called the "sleeve." (That's where the term "TRS Connector" comes from.) In a stereo connection the tip is the left channel signal, the ring is the right channel signal, and the sleeve is the common return ground. Your camera is wired for a stereo microphone that has the same arrangement, the mic actually being two mics in the same handle with one of them connected to the tip and the other to the ring.

You mission, should you choose to accept it, is as follows:

If you're using an unbalanced pair of output connectiors on the soundboard, one for left and the other for right, (get "Y" adapters that) connect the pin in the center of the connector in the left channel jack (usually white) to the tip of the miniplug into your camera, the pin in the right jack (usually red) to the ring of the miniplug, and the sleeve of both jacks to the sleeve of the miniplug at the camera end.

If you're using the BALANCED outputs on the soundboard you might be using two of them for a left and right stereo signal pair, or just one of them for a mono signal. Coming from each balanced output you need to convert the signal in each cable to unbalanced them - two unbalancing adapters - and then to the "Y" connector so the left channel goes to the tip and the right channel goes to the ring of the miniplug. If the signal from the soundboard is mono, you'll only have one cable to worry about and the unbalancing adapter just needs to send signal to the tip of the minipug, the ring and right channel being unused.

Adapters like the Beachteks Glenn recommended make it simple because they can do all this in a single box and even take a single mono input and parallel connect it properly to both the left and right channels on the camera's miniplug so you can record the same signal to both channels at once.

Quote:
You said:
"The camera actually has a -30dB pad built in that you can switch on from the menu so that can account for part of the required drop if you wish to use it."

What do you mean by that? I see where i can turn the Attenuator on or off. When I turn it on, the volume records noticeably softer...-Scott
As you gathered, the high signal coming off of the soundboard will have to be dropped in level so it doesn't overload the mic input on the camera. Let's say we've figured out we need to drop it by 50db. According to the camera manual, there's an attenuator switch (as you've discovered) that puts a 30db attenuator on the input when switched in. That's why the sound is softer - the attenuator reduces the signal just as it enters the camera and makes it weaker. That's eactly what we need to do with the signal from the soundboard, just more so. So if we need to lose a total of 50db, we can take care of 30 of that by switching on the attenuator in the camera and add an inline pad that loses another 20db to come to the total of 50db we're looking for. Shure makes one that sells for about $45 that's switchable between I think it's -10db, -20db, and -25db and you'd need one for each cable from the soundboard. Again, soundboards are different from one another and some have level trim controls on each output that would let you turn it down by 20db as it leaves the board so the pad in the line might not even be needed at all. This would be especially true if the board had the unbalanced left and right "tape out" mentioned above and you were able to use them to feed your camera. Something like the Beachtek is often able to accomplish a lot of the sort of thing in one box. I'm just a big believer in understanding what the black boxes need to do so you can choose the right ones.

Hope this is helping.
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Old July 10th, 2005, 07:16 PM   #10
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Scott, if you can give us the make and model of that house mixer you want to take a feed from, we can probably tell you exactly what cables you need.

For wedding-specific advice, be sure to check out the wedding and event forum on this site. If you have a $5000 budget above the GL1 you already own, you can assemble a very good wedding outfit. Even I have some recommendations, but they would be off topic for this forum.

But do let me repeat this sage advice: For weddings you want to have backups for everything. If you think you were embarrassed by the sound quality at the recital, imagine how you (and the principles) would feel if you were dead in the water at a wedding. Been there (years ago, s-video days). Pretty much lost a friend.
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Old July 10th, 2005, 10:28 PM   #11
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Steve:
A think there's a few important things a Beachtek does better than a simple adapter.
A- The mic jacks on camera will put out "mic plug-in power" (or whatever the proper term for it is). If using a simple adapter, it may not have a blocking capacitor which allows hum/buzz into the recorded audio.
B- It unbalances the audio while maintaining the noise cancellation of balanced signals. For long runs this is very nice.
C- Pots to trim the levels down so they don't overload the camera's inputs. At the same time, you can maximize the S/N ratio you're getting out of your camera.
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Old July 11th, 2005, 01:47 AM   #12
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Glenn, point of information: Unlike Sonys, GL1 and GL2 don't have powered mic jacks.
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Old July 11th, 2005, 08:29 AM   #13
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Quote:
Originally Posted by Glenn Chan
Steve:
A think there's a few important things a Beachtek does better than a simple adapter.
A- The mic jacks on camera will put out "mic plug-in power" (or whatever the proper term for it is). If using a simple adapter, it may not have a blocking capacitor which allows hum/buzz into the recorded audio.
B- It unbalances the audio while maintaining the noise cancellation of balanced signals. For long runs this is very nice.
C- Pots to trim the levels down so they don't overload the camera's inputs. At the same time, you can maximize the S/N ratio you're getting out of your camera.
Agree completely - just was giving Scott "food for thought" as to what all the terms mean, what needs to be accomplished at the signal level and why it's important. Didn't mean to suggest that a simple adapter would do it as well as a purpose built tool like the Beachtek. Something like the DXA-4P, perhaps with a little extra attentuation in the line(s) coming from the soundboard, seems almost ideal for him if he ties into balanced line level outputs on the board. (I'd be a little cautious sending full +4dBU line level straight to the Beachtek, I don't know how susceptible its input might be to overload even in the LINE setting). OTOH, if he ties into unbalanced line level outputs on the board like its tape-outs, the Beachtek might not be the best option.

'Course he could always get something like a Sound Devices 302 or 442 and be all set for almost anything he might run into. Little bit more expensive than the Beach though. <grin>
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Old July 11th, 2005, 09:32 AM   #14
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Steve, except for the DXA-8 which has a preamp, BeachTeks are passive and have no circuitry to overload. They basically consist of the XLR connector, a transformer to unbalance and impedance match the signal, a potentiometer to pad it down, and the unbalanced mini output connector. The mic/line switch may select two different transformers, or add resistance, or both--I'm not sure.
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Old July 11th, 2005, 11:37 AM   #15
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Quote:
Originally Posted by Fred Retread
Steve, except for the DXA-8 which has a preamp, BeachTeks are passive and have no circuitry to overload. They basically consist of the XLR connector, a transformer to unbalance and impedance match the signal, a potentiometer to pad it down, and the unbalanced mini output connector. The mic/line switch may select two different transformers, or add resistance, or both--I'm not sure.
Re-reading the info on their site, you're right. What threw me was they label the level controls as "gain" controls when in fact I guess they are actually variable attenuators. I usually think of "gain" as meaning amplification while attenuation is the opposite. My confusion.
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