Bloated speakers/weight wise

Macrojack: Naturally your speaker cabs do resonante -- all speaker cabs resonate. I'm surprised that you and Line say you can't feel any vibrations with your hand placed on the cabinet. This is true with any surface, at reasonably lifelike volumes, playing any music? As for rocking, most speakers won't do this to any detectable degree if well designed and anchored.

Even if they don't obviously vibrate a great amount, the large areas of the cabinet surfaces involved in making a 4 ft. high speaker means there will be sonically significant unwanted contributions from the cabinet. The effect is potentially worst with speaker constucted from flat panels (as most still are) -- speakers with curved cabinet surfaces have a theoretical leg up here, especially if we're also trying to keep weight down to sane levels.

No matter what you do with the bass, cabinet talk will exist if there's a cabinet involved, but obviously speakers that roll out on the bottom sooner than others will have lesss of a problem to deal with, and this I assume is a factor with your speakers. BTW, I agree that 70 lbs, which is what my own Thiels weigh (with their 1" panels, 2" baffle, and 5 internal cross-braces), is at most mid-weight for a 4 ft. floorstander.

I do have to admit to a lack of basic understanding in a technical aspect of what you're alluding to here though. John Atkinson has also commented in a few speaker reviews that higher sensivity should translate into less cabinet talk. I think I understand why this would be true with horns, because they work by concentrating the sound pressure in the direction of the listener, thus reducing the overall driver excursion needed to achieve equivalent perceived volume levels. What I don't understand is why this should hold true for direct-radiators like yours, because the amount of air that's required to be moved to achieve any given volume level is the same, no matter what the efficiency of this type of speaker. In other words, I understand that the required amount of watts of power needed to achieve that air movement will be less with a more efficient speaker, but not why, if it's making the same SPL in-room, there would be less excitation of the cabinet. Anybody enlighten me on this one?

Zaikesman, what you say about horn speakers makes to me in the same way it does to you and I cannot enlighten you on why efficiency should make any difference other then horns.

I tried to feel vibration again, this time at a louder level and had no trouble feeling it with my hand flat on the cabinet.

I have the larger Walsh Ohms (the older trapezoid style). The cabinets have generous cross bracing and some lead on the all 4 sides but not that much. Now what is different with these speakers is that the driver is not 'in' the cabinet, the driver is outside and on top of the cabinet facing down. This eliminates all chance of rocking the cabinets, but I don't know if this would also reduce cabinet talk. One of the things these speakers are known for, is there beep base (25hz) with authority. There is a port on the bottom of the cabinet.

I don't think I can really hear 25hz, I have this one cd that really goes low with electronic sound, but I don't no how low; I don't so much really hear it all that much but I can feel it and so does the floor. My ears are 63 years old and I know they don't perform like when they were 16.

Another advantage of having the full-range driver mounted to the cabinet top is that the "baffle" is thus made really small, while none of the larger-area cabinet surfaces are excited directly by a driver mounted in the middle of the panel. BTW, I thought Walsh Ohms had fairly low sensitivity, since their sound is radiated equally in all directions. Anyway, you can tell a lot about the cabinet sound of a speaker just by doing the knuckle-rap test at different spots on the various panels and listening critically to the results, no test equipment needed.

Zaiksman: "sonically significant unwanted contributions from the cabinet"...."a 4 ft floorstander @70 lbs is almost midweight for this size cabinet"...
I think its fair to say 95%+ , honestly I'd put it at 90% of the audible sound comes from the drivers. Besides many speakers, B7W's have baffels, which release any excess energy, so the cabinet has minimal resonance.
70lbs "mid-weight" are you saying average for athat size cabinet ot mid weight in general terms?
Sure I guess B&W's and others with the dimensions of your Theils, Tylers, Zu's all average 70-90 4 ft floor stander. But there are 4 -6 ft floorstanders like Wilsons and others that go into the hundreds of lbs. I think people identify heavy with good. Gee if it weights this much, it must be worth the price. Anything I'm not comfortable moving by myself, I'm not interested. I'd did say 150 lbs was my top limit. I've just lower that to 125. btw Tyler offers on 2 of his models a dual cabinet/stack option for each cabinet. Which is unique and pretty cool. I bring up Tyler often here on the board not because I've heard them and know how they sound, but for his innovativness, look at his models, no lab even comes close to what he offers. and the fact he uses Seas' drivers. How he has the xovers will determine just how great a value they are. But just on my knowledge of his component costs, its the best bang for the buck in speakers. By far.

Bartokfan: I assume that what you're referring to in B&W speakers, which is shared with many other speakerers, must be their internal bracing? If so, yes, internal bracing is pretty much mandatory for any speaker that asipres to minimal resonance, but the need for it can be lessened by employing curved outer surfaces, an approach which reduces weight.

I don't know what the percentage range would be for typical audiophile box speakers in terms of cabinet contribution to their total output, but you have to remember that energy reradiated from the cabinet has been shifted in frequency and time -- in other words, it's heavily distorted in relation to the desired goal of the output signal closely matching the input signal. As we know from various kinds of distortion is our electronics, if the effect is musically unconsonant or obscuring, distortion can be audible at very low percentage levels. True, within the signal chain speakers in general have much higher overall distortion percentages than do electronics, but if you want to make a better-performing speaker, you need to address these limitations wherever you can.

I'm in agreement with you that for me, any speaker I can't hump around comfortably by myself is just something that I'm personally not interested in owning, but I do think imposing such a limit probably puts a ceiling on the performance that can attained with typical speaker designs if part of what you like to play is full-range, dynamic music at higher volume levels.