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Totem sky tower owners - how do your mass loading ports behave?

Hello, I took a long hiatus from the forum but I remembered after finding another thread here for another search about NAD vs Cambridge Audio that I have an account here!

As such I thought it would be a good way to increase my sample size of totem owners, specifically totem sky tower owners if possible to post in multiple places. You see to make a long story short I own a couple different pairs of totem sky towers (for a full range 5.1 system :D) and recently through some observational testing I noticed a peculiar difference between my first, older pair of towers and my newer pair of totem sky towers.

First pair has serial numbers around the 01400s (so 1400 ish units produced) and they do not exhibit any pressurization or excitement of the mass loading port at moderate volumes. I haven’t really made observations at different volume levels but I feel that having a difference at any volume level is reason enough to be curious. To be clear I have not added any material for mass loading and have not covered the ports, but I feel no air with my hands, and placing a thin piece of torn receipt paper over the port doesn’t really show any movement or cause vibration.

Second pair has serial numbers almost exactly 1000 units later at 02400s and they DO exhibit a pressurized mass loading port. Placing my hand there it’s easy to feel the air moving. Placing the thin piece of receipt paper there makes it even more obvious as the paper vibrates considerably. I believe it is a vacuum pressure, that it is sucking in air although it might be doing both sucking and pulling along with the movement of the cone.

I would very much appreciate any totem tower owners, especially totem sky tower owners to simply observe the air movement around your mass loading ports and report back your findings. Be sure to include your APPROXIMATE serial numbers. DO NOT GIVE THE ENTIRE ACCURATE SERIAL NUMBER. I’m not sure if that would be enough for someone to steal your warranty or anything but let’s not take chances. The serial numbers could help us narrow down time where changes might have been made to the construction though so please ball park them.

Thanks for any replies and interest. Happy Holidays.
rookiophile
rookiophile OP
9 posts
 
To be clear I'm not looking to do any mass loading this is simply concerning whether or not the mass loading port should be pressurized. So far, other totem owners (Staff, Hawk, Arro) Seem to be saying that the mass loading chamber should be isolated from the speaker cabinets and so I should not notice any pressure in the mass loading port. Yet there is a clear difference there between my older and newer pair in that the old pair does not show any signs of a pressurized mass loading port and the new ones clearly have pressure in the mass loading chamber. I haven't done anything differently to either pair. 

I did not yet remove a driver from a speaker that has no pressure in the mass loading port but I did happen to look inside one of my newer sky towers for an unrelated purpose. I did not see any loose batting or damping material at all that would potentially block any cabinet chambers.

As far as I know the mass loading chamber should be isolated from the speaker cabinet, otherwise laying down the speaker in the way you describe would easily result in sand/silica filling up the speaker cabinet which would be terrible. However totem themselves specifically say that is the approach you should take in mass loading the speakers, so I have to assume that the chamber is meant to be sealed/isolated and something is amiss with my newer towers. Or there has been some kind of design change but it seems unlikely for that to occur with no mention whatsoever from totem.
garry2's avatar
garry2
13 posts
 

No, the mass loading port should not be pressurised as it is a completely separate area from the speaker cabinet. It is designed to be filled with sand cat litter lead shot etc to help the cabinet vibration characteristics. I find the fact that there is no Wadding in the speaker box at all in these speakers fascinating as the port would need to b tuned to perfection. I am currently experimenting with a little wadding in the speaker housing for tweeter off-axis reflections and to curtail out-of-phase resonances. these speakers can be a little bright with some electronics and my Bel Canto amps are clear but a little forced sounding with the Sky Towers. I prefer them with the Graheme Audio Ls5 Model with which the Bel Canto amps are perfectly matched. 

garry2's avatar
garry2
13 posts
 

Put a 1/4 inch thick piece of wadding along the back of the speaker cabinet and up to the top edge at the front where the tweeter is and now everything is deeper and airier. No Brashness to the tweeter. Did a sweep and was much better around 6-8 kHz. Flatter and better response. A little bit of wadding has taken the edge off. Dispersion in the cabinet is much better Phase wise, 

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