To all, Ron N wrote; >As far as action response, perhaps that "crispness" in the treble could be >little more than the geometry inefficiencies resulting from the shorter >keys and wippen heel/capstan intersection height offsetting the lessened >inertial mass of the hammer/shank somewhat. Making it too efficient may >make it feel too "easy" in the top end. Just a thought. Perhaps. >Past a certain >point, it gets tough to determine what causes what in tactile perception. I think we more or less paraphrased each other here with simultaneous posts. >Top and bottom plates would certainly help control key flex in these longer >keys, but I'd wonder that there isn't a considerable difference in feel >resulting in different proportions of mass between the keys and action >parts. In general, heavier action parts would require more leading or more spring pressure to achieve a desired down weight. There is a limit to the amount of spring assist which can be provided without reducing checking efficiency, while extra leading will increase overall inertia. In the case of the extreme treble, a heavier hammer might reduce the requirement for back leading. This would reduce key inertia, but the added inertia of the heavier hammer might well offset this gain. >For instance, given similar UW and DW, would a lightly weighted >treble hammer on a long key feel different than a light hammer with >weighted long key Probably. If the extra load (weight) is placed in the hammer rather than the key, the inefficiencies of the friction between the levers (which still exists even in a well designed action) will tend to reduce slightly the overall efficiency. But we're probably going to spend a lot of time trying to prove all this stuff at the bench. > or a shorter key with compromised wippen/capstan contact >height, or a shorter key with optimal W/C with weighted hammer or key? >There are a whole lot of different combinations in varying proportional >degrees that would probably map into a fairly broad perceptual curve if >everything was tried systematically and put together in a cause and effect >chart of sorts. I know a lot of this kind of thing has already been done, >but I don't know how exhaustive the experimentation was, or how one would >find the information. I'll bet that speculation far exceeds testing for most of us (corporations included). > I can't imagine a designer giving even a passing >thought to whether it's easier to reach tuning pins or not. I have with our designs, but I have no idea how widespread such considerations are. >He'll probably >be having enough troubles trying to fit a minimally compromised instrument >into the manufacturer's outlined box. I don't believe manufacturers should be using an existing box when drawing up a new design. We've little hope of coming up with a wholistic new design if we're stuck with 'last decade's' rim design. While budgetry constraints can dictate such a course of action, we should endeavor to move our industry beyond the mediocrity of repeating the past. >I don't like the increased tuning pin >to counter bearing idea much either, for the reasons you mentioned. This whole matter of string terminations is desperately in need of a rethink. I can't abide these rattling trebles that we've been stuck with over the past century. Often, the string length in the front duplex is too long (what's worse, some makers try to make them 'in tune' with a harmonic), and excessive lengths from the pin to the counter bearing make a bad situation worse. >Acoustically, yes, I think there's too much soundboard behind the treble >bridge too. That should be realistically within the designer's area of >choice unless he's working within a manufacturer's existing rim press >and/or plate pattern limitations. Exactly. >I do think I can make a case for the belly bar dog leg in the treble >though. It's to get the bridge footprint as far away from the rim as >possible within the limitations of the hammer placement, determined by the >V bar and strike point. That's also why treble bridges are undercut, or >beveled along the front of the last couple of octaves. The bridge/V >bar/strike point are in a fixed relationship (theoretically), and the belly >bar position is determined in the design phase to accommodate them. While I take your point Ron, if the strike line is pulled back towards the stretcher, all of the other components (bridges, V bar and belly rail etc.) should be positioned according to the placement of the strike point. >Down >scale a little, it jags back to allow clearance for the dampers, even >though that moves the rim closer to the bridge, it's a less critical >difference because the bridge is far enough away by then that it's doesn't >cause a big change in flexibility. I presume that you mean 'belly rail' (is this the correct US terminology?) when you mention 'rim'. But I still wonder if the flexibility around note F#70 might be improved if we minimise the necessary compromise which the dampers force upon us? What do you think about the approach I have used with my 170? (he writes as he leaves himself exposed to unbridled cannon fire). > What's it all mean? I don't have anything like nearly enough information to >draw lines, but I can still speculate. Like you, I'll take any information >and clarification anyone has to offer. We're all flying blind up to a point. Beware of those who think they aren't, surely they're somehow on a collision course. But then again, they might have a large corporation behind them to support the myth. Unfortunately much of current corporate piano industry thinking seems to be that 'sales speak' is the way forward, and that a good design from a competitor can be fought off with clever, smart alec marketing (not to mention a little reputation undermining thrown in for good measure). It's time we piano techs' sold our message to all in the piano industry, manufacturers, sellers and buyers. Why should we sit back and let the marketeers drive us mad with stupid scales which won't even hold tune until you get the kit back in the car. Furthermore, when the client phones a week later because it has rained (and it was fine when the piano was tuned) causing his/her piano to go out of tune. You are suspected of 'making excuses for your incompetence' when you try to explain that the percentage of breaking strain across the scale in question is as uneven as it gets. Once again the tech' gets the blame for a problem which stems entirely from a poorly conceived scale (I have had this happen). Apologies for my concluding digressionary rave. I shouldn't stay up writing so late. It causes my diplomacy filter to malfunction. Regards to all. Ron O -- Overs Pianos Sydney Australia ________________________ Web site: http://www.overspianos.com.au Email: mailto:ron@overspianos.com.au ________________________
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