Recent content by nbontra

thanks for the info, i surely appreciate it!

I'm constructing a diorama of a ship sinking, and I haven't been able to find any details on the physics behind it. I'm an art student, so my knowledge in physics is limited to what I read here and in a few books at home. I'll most likely construct a fish tank that is 4'x1'x1' to contain the...

It didn't mention anything that I could see; but if the 8 ohms of a normal speaker is a nominal resistance that varies, then making a magnet with a constant resistance of 8 ohms would be seen as "the perfect speaker" by the amplifier. Right? I'll study up on it some more tomorrow, thanks for...

I did the math [correctly, i hope] and plugged in 8 ohms for resistance as that is what my receiver states as the minimum. That gives me: 30 volts, 3.75 amps, 8 ohms, and 112 watts at peak power. If I understand electromagnets, the current is what determines the strength. So if I can...

I've posted on here a few times concerning the electrical problems I continue to encounter for my video installations. And yet, here's another one. If anyone remembers, I posted a month back or so concerning the use of an audio signal from a home audio receiver to open and close a small...

wouldn't the tank of compressed air run out eventually? its for an installation so it would need to be totally self sufficient. what kind of electric valve though?

I can't thank you enough warren. My lack of knowledge in electrical systems is a constant setback when i think of these setups. You've been more help than the entire engineering department at my college. Thanks!

Would it make a difference at all if I could run the whole unit [amp/speaker/compressor] off of a 12V car battery with an AC charging unit on the battery to keep the level topped off? If so, then I could use a small car amplifier [200wX2] and the compressor without having to arrange for current...

Thank you for all the help, I will do my best to learn about how to construct and use an electromechanical valve. Maybe i'll pay the kids in the engineering department on campus a visit.

Wow, thanks for all the input! If it helps in the discussion between NoTime and Chroot, the compressor will be pumping air at the bottom of a 10 gallon fish tank, under about 2.5-3 feet of water.

Warren, thanks for confirming my suspicions. Could you explain the bit about using a variable valve and the envelope detector? Danger, I have a habit of making simple mechanics extremely elaborate just because i like the way it all looks when working together. Similar to the old rube goldberg...

I usually carry alligator clips in my schoolbag for just such a purpose, when a spontaneous music session is needed. If it is a really faint signal, I've had luck hooking it up through the Phono input on HT systems. A few times, I've noticed that the preamp worked better as it needed to bump...

Hi, I'm currently an art student at the University of Houston, and I've run into a bit of a roadblock. I'm working on an installation in which an audio signal from a headphone jack will be sent to an A/V Receiver Unit. From the A/V unit, the wiring for the left speaker will be hooked up to...

I like the idea of using the rod and paddles, it seems much more reliable than my original concept of the balancing weights. Thanks so much for helping me out, I'll be sure to post the results!

I read a little bit on the linear solenoid actuators, and it seems like that would be an ideal solution, especially with the low voltage input. They would be powered for around 30 seconds at a time, but could go as long as a constant 4 minutes. I wish I could just go with the "dummy slide"...