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By: Gary DeRoy
This article is mostly about some hand made options for my Sony DCR TRV38 camcorder. I may never publish it, but I may link to this page or individual pictures from time to time in different forums and I'll certainly use it as personal notes to plot my progress and remind myself of things I want to do.
I've had the Kalimar K-482 fluid head tripod since the mid 1980's. Back then, I used it with my RCA stereo video camera and portable Minolta stereo VCR. Camcorders weren't popular then. It's a little heavy, but it's a great tripod and I can't see any reason to replace it. Once I got some of the camcorder basics figured out, which lenses, lens hoods, microphones, batteries and tapes I wanted, other needs started trickling in. As I did more and more recording, the list of things I needed started to grow. It wasn't too long before I knew I'd need an LCD hood, a microphone shock mount and a good windscreen. These things are all available commercially, but none of them perform flawlessly or has all the options I thought I'd need.
The 1st thing to strike me was the need for an LCD hood. The TRV38 has a nice, large LCD screen, but when you have bright sunlight behind you and you're trying to follow some distant action, it can be hard to see. I really noticed this while recording my son's lacrosse games. It's fast action and the ball isn't very big when you're zoomed out. I needed all the resolution I could get to follow it. I looked at the hoods being marketed on the internet and also read some reviews. They seemed expensive for what you get and most of them didn't look like they'd really get the job done. Some had awkward mounts and most had a generic, "one size fits all" fit. I felt I could do better without a lot of effort. So, I folded a long piece of lightweight cardboard into a rectangular tube and took it outside with the camcorder to do some testing. The hood had to be long enough to keep the light out, but short enough to get me close to the LCD screen so I could see the image details. I put the camcorder at all angles to the sun and started clipping away at the cardboard tube. I finally ended up with a length of 6 inches. This kept out the glare as well as a longer piece and still gave me a good view of the screen. I also played around with glass and Fresnel lenses to magnify the image. That reintroduced glare, so I opted to wear a pair of 2.5X standard reading glasses (small, rectangular and worn low on my nose for looking down at the screen). My normal reading glasses are 1.2X, but with the stronger lenses I was still able to focus with my hood length and it really increased the size of the image. There's no problem following that little lacrosse ball now, even at a distance. What a joy to use.
The hood is made up of medium weight, corrugated cardboard, picture
hanging hooks, a black rubber band, 'silver' and 'stove black' paint,
and super glue. I made the cardboard long
enough so that the finished hood would leave a 1/8 inch boarder around the
LCD screen and added a 1/2 inch tab on one end to glue to one
side. I measured and marked the fold lines with a pencil. To get a factory folded look, I used a re-screening tool (a thin wheel with a handle that you can pick up at any hardware store for a couple bucks) to crease the
cardboard. I put the wheel over the pencil lines and used a thick straight edge for a guide. A couple light passes and then a couple heavy ones on each side of the cardboard was all it needed. Making the folds was easy and they didn't wrinkle, leaving a factory look.
The inside is painted 'stove black' to cut glare and light, and the
exterior is painted silver to match the camcorder. I considered many
different methods to attach the hood to the LCD screen, but ended up
using some cut off picture hooks. This image shows the hook with the
nail (in red) that mounts it to a wall as it's intended to be used Since I already had the paint, super glue, hooks and rubber band, this project didn't cost me anything. If you have to buy the hooks and rubber band, it might cost 99 cents. The hood folds flat (except that the hooks protrude a little), fits the camera, looks good, works great and didn't cost $50.
The shock mount for the microphone is a work in progress. I'm not really sure which mics I'll be using so I don't know how tall to mount it above the camcorder. I may use a shoe adapter connected right to a nut on the bottom of the shock mount, or I may raise it with a mic clip or some other stand-off. I decided to go with a tube style shock mount instead of a metal frame style because I thought I would be using 2 ATR55 mics in an XY configuration for stereo recording. With a tube style mount, I could stack them with a bolt and nut going from the top of one and into the bottom of the other. That way I wouldn't need a stereo mic bar. The tube is cut from a piece of white PVC pipe, 1 1/2" ID, to make the mount. I used a band saw and guide to trim it at 3 1/2 inches and square the ends. I don't have a lathe, so I used my drill press to turn it and a file to put the grooves near the edges. Besides looking finished, it creates a lip to secure the rubber bands. The holes in the side were made with a hole cutting bit on the drill press. They serve 3 purposes. It looks better. It enables me to reach the on/off switch on the mic, and when thumped, it helps to dissipate the hollow, drum sound. The slots for the rubber bands were cut with a Dremel tool. The hard part was lining up the cuts so the X would be centered in the opening. To do this a made an X template on my computer. I wasn't at work, so I didn't have access to my CAD program. I used Paint Shop Pro instead, making each leg of the cross pattern 28 pixels wide. Then it was just a matter of cutting out the printed pattern, placing it over the end of the tube, eyeballing to center it and marking where the cuts should be. Everything was sanded and painted 'stove black'. The mics I'm using are about .8" in diameter. For larger mics, I can place the rubber bands in the wider spaced slots, supporting the mic in the typical cross pattern fashion. Since I have plumbers on jobsites all the time, the PVC pipe didn't cost me anything. If you go to a hardware store to get it, expect to pay about 40 cents for a foot of it. The black rubber bands are the same ones used by girls to put their hair in pony tails and such. They're probably 99 cents for a large package, but I got mine free from my teenage daughter. Since I already had the paint, this project didn't cost me anything either, but I may have to buy a 10 cent nut to attach the shock mount to the camcorder shoe adapter. It's better than spending $40 and up for one already made. It works great, looks good, it's strong and it's expandable if I ever need to stack them for using 2 mics.
[updated]
One of my favorite things to do is going to the hardware store and poking around The tall bolt is called an "elevator bolt". The head is actually round, but I didn't take a picture until after I trimmed it a bit to fit my camcorder shoe. This bolt is usually used on the bottom of furniture legs so you can adjust the height and level it. The brass nut next to it is often used with the elevator bolt. A hole is drilled into the bottom of the leg, the nut pushed into the hole (pressure fitted) and the bolt screwed into the nut. There's a black fiber washer which I picked simply because of it's color, a regular nut, a rubber grommet that will be glued to the outside of the nut (so it can be tightened without a wrench, and a rubber "well nut". The parts cost me under $3. A hole was drilled through the bottom of my shock mount and the brass nut pushed through it. Here's how the pieces look together.
I also picked up some O-rings that I'm using (for a while, at least) instead of rubber bands to support the mic. The O-rings will last forever, but they aren't as flexible as rubber bands and they can't be too tight or they'll transmit the sound to the mic. Instead of stretching them across the mount in an X pattern and sliding the mic through them (as I did with the rubber bands), each O-ring goes around the mic and is attached to the mount in only one place (instead of 2). They really grip the mic and they're dead quiet. No sound is transmitted through them. All in all, this project with the shock mount and shoe adapter turned out pretty good. The parts do everything they should do, they do it very well and look pretty good, and they're easy to use.
Update: My new shock mount is better because it has holes on top for reaching the microphone on/off switches. The grooves around the outside that hold the O-rings are deeper and the slots are arranged differently. It's also set up to hold the windscreen I'm working on.
I did quite a bit of experimenting with windscreens. Even the foam windscreens that come with the mics work to some small extent, but nothing (short of thick padding that ruined the frequency response) I saw would completely eliminate wind noise. I tried placing different materials over the mic, then over mic with the foam windscreen also attached, and came to the conclusion that if the windscreen touches the mic at all, it won't totally stop the wind noise; but, if the windscreen is held away from the mic, it stops the noise almost completely even in strong winds. The problem, then, was how to put a windscreen on a mic without touching the mic. The solution I came up with is to mount the windscreen to the shock mount, not directly to the mic. (Note: after looking around at some expensive windscreens, I found there are some like the Rycote Softie and Blimp that use this principle, but I believe they cost hundreds of dollars.) I'd like to build one shock mounted windscreen that will work for whichever mics I keep (probably the ATR55 and AT822). Since my AT822 hasn't arrived yet, I don't know what size the dual element head is and don't know if it'll fit in the same size windscreen as the ATR25 or 55. Also, the AT822 can't be feed through the shock mount from the rear (the head is too big to go through the rubber bands), so the windscreen will have to be detachable. I've been experimenting with different materials like cotton, nylon and foam, all with some success. The test below was conducted with a sheet of open foam (used for packing computer parts) that I rolled into a tube and slipped over the mic and shock mount. It's important to realize that there are 2 fan noises. One is the noise from the wind created by the fan. This is what we want to eliminate. The other is simply the noise of the fan running. Even if the mic were behind the fan and out of the wind, it would pick up the sound of the running fan.
Here I've changed the mic and the windscreen material. This is the Audio-Technica ATR55 and a nylon stocking for the windscreen. This mic is more directional than the ATR25, so it picks up less of the fan background noise.
More to come ......
The music selection used in the microphone tests is from "Little Girl Blue" on Linda Ronstadt's "For Sentimental Reasons" CD. This is how it sounds with the MP3 taken directly from the CD. It's important to keep in mind that the mic versions cannot sound like the CD version. They are recorded through my stereo system speakers with an equalizer and bass management system. The sound is contoured. The sound on the CD is not. NOTE: If you're going to do side-by-side comparisons of these sound files, remember that louder music usually sounds better at first. I did my best to make these selections close to each other in loudness without using extra filtering, but they are not exact matches. Use your volume control to adjust the sound level of each file.
Here's the selection recorded with the Audio-Technica ATR55. Since the mic is mono, I changed the mono plug on the cable to a shielded, stereo mini plug and bridged the left and right channels. To simulate 2 mics, I used Nero's Wave Editor to put a small amount of stereo separation between the channels. This mic isn't really made for recording music, but it's quite good when used as a shotgun mic as it is intended to be. For this recording, the mic was set to "normal" mode. In "tele" mode, the pattern is narrower and I could easily pick up the sounds of the kids playing at the end of my driveway, 275 feet away.
This is the selection on the Audio-Technica ATR25. The overall tonal balance is pretty good for a mic that usually sells for under $40. It's a little weak on bass as most mics in this price range are, but I could compensate for it using Wave Studio or an equalizer.
This one is with my Audio-Technica AT822. This is a great, stereo mic. The recording is not retouched. I just changed it to MP3 format. The mic, as they all were during this test, is between the stereo speakers, but not far enough back for proper imaging. I'm surprised it turned out as well as it did. I had a noisy environment this time, too. The computer, a fan and the dishwasher were all running in the background. It's quite sensitive, recording about 10db higher than first two mics. It displayed no self noise whatsoever, extremely accurate tonal balance and outstanding dynamic range. It has a street price of under $250 and gives very good performance. This recording was done with the bass roll-off turned OFF.
The output on the AT822 is higher than a lot of other mics. If the sound source
is too loud, the signal from the mic to the camcorder needs to be attenuated. I
didn't want to use a mic pre-amp because of cost and because it's just one more
thing to hold while I'm shooting. The simple solution I came up with is to use
an Keep in mind that any cable you add between the mic and camcorder will probably add a little background noise because the cable is longer and it's going through more connections. The right solution would be to buy an complete new cable, attenuated to about -30db, and change cables when necessary. Lucky for me, the AT822 has so little self noise that adding the cable made no perceptible difference.
Nady Systems was kind enough to lend me one of their CM-2S stereo mics for a review. The output on this model is even a bit higher than the AT822, so once again I used my attenuating cable and I also lowered the source volume. The sound pressure measured 65 to 70 dB for most of the selection, but when Linda belts out the word "gold", it hit 80 dB. The CM-2S has a street price of around $110. It has a bass roll-off option like the AT822 and for this recording I had it set flat (OFF). It's pretty obvious that Nady Systems was targeting the same market with the CM-2S as Audio-Technica was with the AT822. Listen to the sound clip and judge for yourself if they succeeded.
Here it is on the Realistic 33-919A. This
old Radio Shack mic is called a "Dual pattern stereo electret
Since the mic is old, it had a couple scuff marks on the lower part of the
head where the color was also faded. So, the second part of the makeover
consisted of a
Above is the finished product. Below is a picture of the 33-919A as I was testing the paint/graphics scheme.
Mp3 jazz selections [CM-2S] [AT822] [AT822 2nd take]
Gary DeRoy (GTX_SlotCar) Written: AUGUST 4, 2005
Last update: FEBRUARY 22, 2006
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and this shows it cut off and laying down as used on my hood 
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I used super glue to fasten two on the top of the hood near the leading
edge and one on the bottom, centered but a couple inches back from the
leading edge. You can see it in the picture below. Trust me, this
arrangement of hooks holds the hood securely, doesn't let it slip down
on the screen, and it's easy to mount. Just hook the rubber band around
the top hooks, pull it down over the LCD screen with a finger and slip
it over the bottom hook. At first I had some concerns about the super
glue holding the metal hooks to the cardboard, but I've been using this
for a few months and they're just as strong now as when I assembled it.
for parts I can use in a way the manufacturer never intended. Today I ended up
with these to make my new shoe adapter for my shock mount.
attenuating
cable, and the cheapest thing I found was a volume control cable for headphones.
There are several attenuating cables made for microphones. Most of them are set
to lower the db a set amount (usually 10, 20, 30 or 50 db), but some can be
switched, giving you 2 or 3 choices. The headphone volume control cables do
about the same thing, but the adjustment is variable. Also, the quality isn't as
good on these so they may not last forever. Still, they're cheap to replace.
Koss and other companies make some that seem a little more rugged than the one I
picked up from Radio Shack, but for under $7, this is working out well, and
frankly, I seldom need to use it.
microphone system". The dual pattern is switchable from 90° to 110°.
It has a frequency response of 30 - 15, 000 Hz and came with a 10' cable and 2
mono 1/4" phone plugs. To use it with my camcorder, I had to use reducing
adapters, 1/4" to 1/8" (3.5mm) and run those into another adapter, 2
mono 3.5mm phone plugs to a stereo 3.5mm phone plug. All the plugs and adapters
together measured over 6" long, were awkward and quite a sight. The mic's
performance was not spectacular, mostly because it was noisy. I decided to give
it a quick makeover, starting with the cord and plugs. I cut the 10' cord down
to 18" and soldered on a good, shielded stereo 3.5mm plug so it would
connect directly to my camcorder. The difference in sound was amazing.
The background noise now is very low. Dynamic range is good, as is the tonal
balance. Stereo separation, while not stellar, is very natural sounding.
partial paint job and some stripes. I think it came out pretty good. It
certainly looks more modern, and it sounds good, too. For this recording, the
mic was set to "wide".
