Film-Tech Forum ARCHIVE: pneumatic subwoofer

This is topic pneumatic subwoofer in forum Film-Yak at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=8;t=001573

Posted by Matthew Bailey (Member # 601) on 12-24-2002, 07:56 PM:

Form reading the post on a pneumatic audio amplifier just gave me an idea. How about a pneumatic subwoofer? This would use a pneumatic solenoid coupled to the cone of the woofer in place of the voice coil. The solenoid would use two inlets & two outlets-the outlets are to allow some of the air to escape. A pair of springs fastened to the solenoid plunger rod prevent the rod from moving excessively & damaging the spider & cone. An operatng valve with one inlet & two outlets coupled to the cone of a small woofer would allow compressed air to the solenoid thus causing the large cone to move in either direction.

Posted by Sean McKinnon (Member # 612) on 12-25-2002, 04:29 AM:

Like the new picture! [thumbsup]

Posted by Paul Cassidy (Member # 951) on 12-25-2002, 04:54 AM:

Is that really you Matthew !?? some how I'll always remmber the Old photo as it is more in keeping with your posts , your waaay out there Mate and you must add color to any place you go [beer]

Posted by Matthew Bailey (Member # 601) on 12-25-2002, 09:05 PM:

Yes it's me. A prom pic of me from 93 or 92.

Posted by Jason Black (Member # 684) on 12-25-2002, 09:16 PM:

What can I say... Sweeeettttt... [thumbsup]

Posted by Jack Ondracek (Member # 1466) on 12-25-2002, 09:44 PM:

quote:
Yes it's me. A prom pic of me from 93 or 92.

Wow... if I'd have known Brad'd go with "classic" photos, I'd have sent in my "impossibly young guy at the radio console" picture. Guess if Dick Clark can do it, why can't we, eh?

Posted by Brad Miller (Member # 2) on 12-25-2002, 10:03 PM:

Having a slightly older picture (10 years or less) is ok with me, but there does come a point where the picture doesn't represent the real person who is speaking. (Some people get wiser as they age, some just get grumpy. [Wink]

)

Posted by Sam Hunter (Member # 1119) on 12-25-2002, 10:14 PM:

I have a new do I might show off. Something Kojak might like. [Cool]

Posted by Bobby Henderson (Member # 840) on 12-26-2002, 05:46 PM:

So now you comb your hair with a sponge? [Wink]

(old Kojak joke.)

Posted by Sam Hunter (Member # 1119) on 12-26-2002, 08:13 PM:

Missing in action

Posted by Paul Cassidy (Member # 951) on 12-27-2002, 02:21 AM:

"WHO LOVES YA BABY " [thumbsup]

Posted by Randy Stankey (Member # 64) on 12-27-2002, 07:34 AM:

Few people can pull off the Kojak look and still look good. Sam, you are one of the few.

Posted by Ian Price (Member # 14) on 12-27-2002, 12:44 PM:

Sam, you're a good looking bald man.

Posted by Sam Hunter (Member # 1119) on 12-27-2002, 05:57 PM:

Missing in action 2

Posted by Matthew Bailey (Member # 601) on 12-28-2002, 08:07 PM:

Allright,let's quit deviating from the original subject I intended. I am 30 years now & I honestly don,t like what you are doing to my subject at all because you think it's amusing when in reality it ism't to me when I'm the victim of it.

Posted by Brad Miller (Member # 2) on 12-28-2002, 09:57 PM:

Matthew, if you would like me to change the picture back to the original one more near your current age just drop me an email. I think these guys just didn't realize that it would be ok to send in a picture that is a few years old and no one has any specific comments about your subwoofer idea at the present time. If anyone should be annoyed it would be Mr. Chuck "Kojak" Norris (Sam Hunter).

Posted by Steve Kraus (Member # 476) on 12-28-2002, 10:20 PM:

I'll comment. I do not think the mechanism as described could move quickly enough for the frequencies involved. They are low to be sure but still faster than I think could be generated this way. This does not preclude some other way of doing it with air pressure however if a way can be found to switch it fast enough.

Posted by Sam Hunter (Member # 1119) on 12-29-2002, 12:55 AM:

Mathew, your idea has merit. The only problem is generating the volume of air needed to reproduce the low frequencies and also the responce time would have to be very fast which means a lot of big pipes. By the time you invest in the control system, air supply, etc it would be much simpler to use conventional systems. Seems like I read onetime about a subwoofer system that uses LP gas or something like that.
I would be careful about posting ideas on forums like this because you never know when someone will steal your idea.