@mglik those Tetra speakers are so underrated you have no idea. You have a great taste.
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A fun note... The mass of concrete i added was bricks and slab of concrete... Around 80 pound more than 75 i think... The look is disguised with homemade resonators glued to the slabs... I will lie if this can be described as beautiful.... This look more like a " mad scientist lair" improvised apparatus.... My speakers are modified with stones and cables and little resonators etc.... My little children are baffled by the look tough.... :) |
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Hi millercarbon, Thanks for the thoughtful post. The original design of the Tetra 606 had exactly what you suggest with struts going from the speaker top to the bass cabinet. I admire your deep knowledge and application in your posts and, certainly, your system. I see the very nice concrete block under your TT. Very attractive. Think the Rouge Fitness vest plates will do the job of mass loading nicely. They are almost exactly the right dimensions. 4 plates would only be 1 inch and 4/16ths and they are black. Have you thought of mass loading your speakers? My speaker designer didn’t like it when I told him but did respect my ears. |
Look closely at the design of your speaker. Notice they have a very thick strong and heavy baffle. Its open, but that is their little design hook. Open baffle is kind of a thing lately. Its an opportunity to learn about the tradeoffs of loudspeaker design, I guess. The change you heard is exactly what I would predict, even without knowing what speakers or how they are designed. Notice mahgister has great results from adding even more mass to his. Whatever they are. Nobody asks mahgister. Interesting.... Basic Newtonian physics, F=MA, force equals mass times acceleration. Our goal is to have the driver move the air while the speaker cabinet remains fixed, so all the sonic energy goes into the air. Obviously if the speakers are just hanging from strings in the air they are going to move a lot, much of the energy gets wasted moving them back and forth instead of moving air, and they sound like you know what. That is the ultimate open baffle, you may like it. I can imagine the superlatives. Among them will not be dynamics. All the dynamics will be sucked out. Adding mass to the drivers will restore the dynamics. And detail. Tremendous amount of detail is lost in cabinet vibrations. So you want to add mass. They already added as much as they could with that big thick front baffle and a woofer cabinet about ten times as big as it needs to be. Still the open baffle design forces them to eliminate the #1 easiest and best thing they could do to improve dynamics and detail and that is reinforce the baffle with a cabinet with sides and back. Oh well. So this is your challenge. How to add mass without compromising the sonic and aesthetic integrity of the design. In a word, you can't. Sorry. But you just can't. Mass would be most effective on top. But you can't put it there because there is no top. Mass would be second most effective behind the baffle. But you can't put it there because baffle shape and size affects frequency response. You could install some struts running from the top corners down to the back corners of the sub cabinet. That would effectively mass load and stiffen the baffle but look like absolute crap. The closest I can think of would be to make a cast concrete slab several inches thick and shaped to sit on top of the bass cabinet. If done right, tapered and painted, it would blend almost seamlessly with the bass cabinet. To get some idea what cast concrete can be, look at my turntable rack. https://systems.audiogon.com/systems/8367 This would be a bit of a project. But if you put in the time you could make it look good enough to keep the wife happy. Maybe. I know all about audio. Women, on the other hand..... |
I am using Tetra 606s. It is especially convenient that they are open baffle on the mid and tweeter and have a separate bass cabinet behind. So I am able to put the weight on the back of the speaker. Much nicer than putting weights on the top of a regular speaker. But maybe I can find a weight that is more attractive than an ankle weight to increase the amount of weight. |
Wow, I actually thought of putting more weight on them. It seems the speaker weight is very significant. Wish I had a dedicated audio room but we both listen and enjoy. I just put on the Mad Max soundtrack and after about 5 minutes Nina ran in from another part of the house and demanded I take it off. I don’t blame her. WAF has always been a factor to consider. Especially since she is pretty agreeable to my spending thousands on my “addiction”. But, mostly, she comes to quickly appreciate and enjoy. I do still love it when she comes over and picks up the record cover to read! |