Is there an adapter to monitor one channel of audio over two speakers? at DVinfo.net

David Lach · November 6th, 2004, 08:43 PM

I own an XL2, I need to use both channels of 16bits audio but the second channel is a fixed ambiant sound and doesn't need to be monitored. The first channel on the other hand will be dialogs and the soundman needs to ear this channel both in the left and right speakers of his reference monitor headphones while shooting.

As it is, when you plug the headphones in the camera headphone jack, you ear channel 1 on the left side and channel 2 on the right side.

I went to Radioshack thinking they might have some kind of gadget to plug a cable in the 1/8 stereo headphone jack and split the XL2's left channel over both left and right sides without degrading the sound, but they don't.

The salesman told me though that Canon made such an adapter for this specific use, but I never heard of it nor seen it anywhere.

Anybody knows about that adapter or maybe an other similar adapter that will allow me to do this?

Jay Massengill · November 6th, 2004, 10:40 PM

Are you working in a fixed location with AC power? Or is this a totally mobile situation using battery power and the minimum of equipment?

David Lach · November 7th, 2004, 01:59 PM

Both. I work in a fixed location but I'm planing to use battery power only. Less wires and cables in the way, and there's a few handheld, crane and steadicam shots that will need to be powered through batteries only. There will be a few outside shots as well, which makes it impracticle to use AC power.

Jeremy Davidson · December 9th, 2004, 12:26 PM

If you are comfortable with a soldering iron (or know someone who is), a simple little switchbox could be built which would allow the headphones to monitor off of only one channel. This would not (theoretically) affect the recorded signal at all and would be completely passive (no batteries). Estimated cost <$10 at RadioShack (or your electronic parts supplier of choice).

Reply here if you're interested and I'll whip up the schematic. Come to think of it, I should build one of these for my GL2. Good idea, David!

David Lach · December 14th, 2004, 09:31 AM

Well Jeremy, I'm not sure how to do it, but I'd be really interested in building a switch that would allow me to either get the sound from channel 1 in both speakers, get the sound from channel 2 in both speakers, or get the unaltered signal with channel 1 on the left and channel 2 on the right. That would be the ultimate accessory for sound monitoring on my XL2.

Jeremy Davidson · January 3rd, 2005, 11:29 AM

David,

I finally got the schematic drawn -- I'll email it to you shortly.

If anyone else is interested in receiving it, please post here (or perhaps someone would like to host the file? It's just a 42k JPEG image).

I have not tested the circuit, but the theory is so simple I can't see why it wouldn't work (unless the headphone amp in the XL2 is so weak that it can't drive the headphones properly). You can test this by getting one of those little headphone splitters from RadioShack and trying two pairs of phones from its output. If the volume stays fairly consistent when you add the second pair, you should be fine. If it does drop, it should still only affect what you hear in the headphones -- the recorded signal will remain the same.

Jeremy

Skye Giebink · January 8th, 2005, 09:21 PM

Would you mind sending that schematic my way? I'm always doing little things with soldering irons.

skyeg(at)sio.midco.net

Glenn Chan · January 8th, 2005, 10:22 PM

Does Radio Shack still sell electronic parts? In Toronto Canada they've turned into just another electronics store, and they sell extended warranties on overpriced $40 firewire cables with lifetime warranties.

You might be able to find a list of local US/CDN electronics stores (real electronics stores that sell resistors and stuff like that) at the following site:
http://www.repairfaq.org/ELE/F_Surplus.html

Jeremy Davidson · January 12th, 2005, 02:40 PM

Skye, I just sent the schematic to you from my hotmail account.

Glenn, I usually order my parts from All Electronics -- a mail-order company out of California. It's not always the highest-quality stuff, but they often have good deals (plus they stock old surplus electronics -- can be great if you don't mind disassembling old boards to get at the parts you need).

http://www.allelectronics.com

November 6th, 2004, 08:43 PM	#1
David Lach Major Player Join Date: Oct 2002 Location: Montreal, QC, Canada Posts: 570	Is there an adapter to monitor one channel of audio over two speakers? I own an XL2, I need to use both channels of 16bits audio but the second channel is a fixed ambiant sound and doesn't need to be monitored. The first channel on the other hand will be dialogs and the soundman needs to ear this channel both in the left and right speakers of his reference monitor headphones while shooting. As it is, when you plug the headphones in the camera headphone jack, you ear channel 1 on the left side and channel 2 on the right side. I went to Radioshack thinking they might have some kind of gadget to plug a cable in the 1/8 stereo headphone jack and split the XL2's left channel over both left and right sides without degrading the sound, but they don't. The salesman told me though that Canon made such an adapter for this specific use, but I never heard of it nor seen it anywhere. Anybody knows about that adapter or maybe an other similar adapter that will allow me to do this?

December 9th, 2004, 12:26 PM	#4
Jeremy Davidson Regular Crew Join Date: Aug 2004 Location: Eau Claire, WI Posts: 167	If you are comfortable with a soldering iron (or know someone who is), a simple little switchbox could be built which would allow the headphones to monitor off of only one channel. This would not (theoretically) affect the recorded signal at all and would be completely passive (no batteries). Estimated cost <$10 at RadioShack (or your electronic parts supplier of choice). Reply here if you're interested and I'll whip up the schematic. Come to think of it, I should build one of these for my GL2. Good idea, David! __________________ There's no way for you to know if what I'm saying is true unless you know what the truth is, and there's no way for you to know what the truth is unless there is a truth that you can know. -- Frank Peretti

January 3rd, 2005, 11:29 AM	#6
Jeremy Davidson Regular Crew Join Date: Aug 2004 Location: Eau Claire, WI Posts: 167	David, I finally got the schematic drawn -- I'll email it to you shortly. If anyone else is interested in receiving it, please post here (or perhaps someone would like to host the file? It's just a 42k JPEG image). I have not tested the circuit, but the theory is so simple I can't see why it wouldn't work (unless the headphone amp in the XL2 is so weak that it can't drive the headphones properly). You can test this by getting one of those little headphone splitters from RadioShack and trying two pairs of phones from its output. If the volume stays fairly consistent when you add the second pair, you should be fine. If it does drop, it should still only affect what you hear in the headphones -- the recorded signal will remain the same. Jeremy __________________ There's no way for you to know if what I'm saying is true unless you know what the truth is, and there's no way for you to know what the truth is unless there is a truth that you can know. -- Frank Peretti

January 12th, 2005, 02:40 PM	#9
Jeremy Davidson Regular Crew Join Date: Aug 2004 Location: Eau Claire, WI Posts: 167	Skye, I just sent the schematic to you from my hotmail account. Glenn, I usually order my parts from All Electronics -- a mail-order company out of California. It's not always the highest-quality stuff, but they often have good deals (plus they stock old surplus electronics -- can be great if you don't mind disassembling old boards to get at the parts you need). http://www.allelectronics.com __________________ There's no way for you to know if what I'm saying is true unless you know what the truth is, and there's no way for you to know what the truth is unless there is a truth that you can know. -- Frank Peretti

November 6th, 2004, 10:40 PM	#2
Jay Massengill Trustee Join Date: Jul 2003 Location: Burlington Posts: 1,976	Are you working in a fixed location with AC power? Or is this a totally mobile situation using battery power and the minimum of equipment?

November 7th, 2004, 01:59 PM	#3
David Lach Major Player Join Date: Oct 2002 Location: Montreal, QC, Canada Posts: 570	Both. I work in a fixed location but I'm planing to use battery power only. Less wires and cables in the way, and there's a few handheld, crane and steadicam shots that will need to be powered through batteries only. There will be a few outside shots as well, which makes it impracticle to use AC power.

December 14th, 2004, 09:31 AM	#5
David Lach Major Player Join Date: Oct 2002 Location: Montreal, QC, Canada Posts: 570	Well Jeremy, I'm not sure how to do it, but I'd be really interested in building a switch that would allow me to either get the sound from channel 1 in both speakers, get the sound from channel 2 in both speakers, or get the unaltered signal with channel 1 on the left and channel 2 on the right. That would be the ultimate accessory for sound monitoring on my XL2.

January 8th, 2005, 09:21 PM	#7
Skye Giebink Regular Crew Join Date: Feb 2003 Location: South Dakota Posts: 54	Would you mind sending that schematic my way? I'm always doing little things with soldering irons. skyeg(at)sio.midco.net

January 8th, 2005, 10:22 PM	#8
Glenn Chan Inner Circle Join Date: Jun 2003 Location: Toronto, Canada Posts: 4,750	Does Radio Shack still sell electronic parts? In Toronto Canada they've turned into just another electronics store, and they sell extended warranties on overpriced $40 firewire cables with lifetime warranties. You might be able to find a list of local US/CDN electronics stores (real electronics stores that sell resistors and stuff like that) at the following site: http://www.repairfaq.org/ELE/F_Surplus.html