Lead shot questions

Elizabeth is right dust would be dangerous to young childrens nervous systems. It may also make you snap for a moment in a rage of anger, & who knows?

First pick up a pair of Sound Anchor Cradle style bases for your Cdm-9nt's, then going from a Bryston 4b-st, to 7b-st mono's will really open up the 9's BIG TIME!!!

The Cdm-9's are fine as is no need to mod them, they just need a major amount of juice to really open them up. I used to own a pair w/ a 4b-st, & 2 Rel Strata III's. Once the 7b-st's where in the system I never felt the need to re-connected the Rel's.

Good Luck!

Audiobugged, LOL. You know me well. I certainly dont need anymore rages. The Sound Anchors is a great idea, I am going to look into it immediately. I should have a 4B-SST next week so the amp is going to improve some, hopefully.

Swampwalker, I didnt even think about the steel and the magnets, a potentially sticky situation! I am a diver, and as an experiment I could place my soft bagged lead weights on top. I only have a pair of 5s and 4s (salt/fresh). So each speaker would have 9Lbs on top. Not a lot, but maybe enought to see if this warrants further consideration.

Thanks so much. More thoughts are certainly welcome.

don't worry about lead dust unless you are going to have it in your mouth or i don't think your speakers are powerfull enough to make the shot move around so much as to create dust. there are tons of people who use lead shot in their speakers and have you heard of one problem? plus compare price of lead shot to sound anchors.

Putting metal weights inside a speaker enclosure is obviously a misunderstanding of the concept of weighting down the enclosure by external loading.

But, it brings to mind an idea that I have been kicking around for a while, but never got to try. Carbon dioxide, CO2, is an easily obtained and non-toxic gas that is heavier than air. One could drill two small holes in a speaker, top and bottom, and fill the enclosure with CO2 (slowly from the bottom). After filling plug the holes, perhaps with a cork. The extra weight would not be enough to affect the enclosure structure, but it would change the enclosure loading of the driver, perhaps in a desirable way. If the effect is in the "wrong" direction, one could try Helium, but that gas would tend to leak out (whereas CO2 would not). Has anyone tried something like this?

Mboldda1, you are right, I have never heard of a problem, though I do find Elizabeth's logic quite sound (no pun). Keeping it bagged would require woofer removal but still no big deal.

Eldartford, can you elaborate on the misunderstanding? Does the weight get stacked on top of the enclosure? I have read a lot lately about mass loading the Von Schweikert VR-4jrs, is that not internal?

The CO2 is interesting and doable. I have a 20LB CO2 cylinder I use to force carbonate Beer kegs. Though, like most B & Ws, the CDM9s are a ported design. I do have the bung plugs. They are made from foam rubber and with the port low mounted, I feel that over time the gas would leak out. Drilling would NOT be acceptable. I could lay the speaker on its back, fill it via the port, then plug it. Blasting the CO2 in for a while would stir the air and facilitate a high CO2 saturation but it would not completely displace the nitrogen and oxygen.