I was mainly trying a combination of things to get it to loosen up which indeed I did accomplish. Sadly my previous post was correct as far as it went.. Then I hit yet another snag when I put on what must have been a very late record and it just couldn't handle it, even though the others were quite good.. So I see why edison had to tamp down the sound. You can't get everything sensitive and reasonably loud and still handle those later more powerful records. Its a shame because my symphony and piano, violin things never sounded so rich.. But his diaphragm must be a compromise of sorts. So now I am trying a damped version, I don't have a lot of hope in it, but heck that is how I got where I was..
This journey has more changes than a leopard has spots.. First my successes today, then a let down, now again the record I couldn't play one of the earlier design made it though quite well. I hope it means I won't have to dampen things down as much as I thought and in fact had already begun some test of.. I much preferred the lively instruments and sensitive classical things I was hearing to the deadened versions. Still having glue issues though. One was too stiff when finished drying, and one too weak, the current one is good, but is having a tendency to let loose under some of the rings that baffle the sound. That may be another issue, long term survival..
Things must happen for a reason as the saying goes.. My disappointment led to adding increased weight to the diaphragm which in turn gave better clarity and solid sound. I resorted to that because there so far had been no other way eliminate that disturbing buzz that the lighter diaphragm was causing.. at first I had rejected it as too much dampening, but after several adjustments the benefits way out weight the objections. Waiting for the other shoe to drop.
I have tested many more records and had very good results. I would almost say spectacular.. Several of the old diaphragms I pried the rings off of just to see if they could be saved.. I am into yet another glue, slower to dry but appears to stay attached to the shellac, at least for now. I was experiencing distortions due to even the second glue type turning loose on the under part. I put several slightly different combinations of center where the majority of the weight is and found that that first one was by far the best. I make one more like it and have it drying. Tomorrow I will see if cloning the first one is possible.. If so I may be getting close in my search.
Odd morning.. I put the reproducer back together to see if yesterdays results still held.. I got a rather puny sound from what I could remember of yesterday.. I played a few records somewhat disappointed.. Then I took the part next door while I walked for my morning exercise. I only have a London model there.. (edison may have done the farmers a favor, but surely no quality of sound from that horn).. Also my records are very spotty and as I walked and listened I wasn't too pleased... I brought it back home and reinstalled it on the sheraton, then I noticed I had evidently damper the mute down by half last night.. Well there was my sound and tone again, thank goodness. Then I tried my own "tone test" against another new product.. I am somewhat amazed at the ability of such a simple thing to give reasonable results that I was getting a bit depressed by all the work.. But as it played on I knew I had found something because the life had gone out of the record and about a third of the volume.. I must say of the several new versions I own, the one today played with a fair amount of clarity, perhaps even less prone to "clipping" as I would call it on fast changes in volume. Or it may be that my diaphragm being more sensitive is just picking it up better? I think I have a bit of a feedback that shouldn't be there compared to Edisons, but heck I am no Edison as the saying goes. I may be reaching my goal of something that out performs what is currently available and ends up between perfect and lackluster. If I can get it replicated it may be something that those with 'dead" diaphragms or none would enjoy until they could find an excellent original? In a few hours I will know if yesterdays test model will match what I have here now. I would be nice for a change..
Second one up and running and very little difference if any between it and the best one yesterday.. I won't say it couldn't be better because they always can be I think, but seems pretty satisfactory.. Now if I can get several more of these that work and out to the friends that have been willing to test them we can perhaps get some feed back as to the pros and cons of my design.
Any one following this have a suggestion for a glue that will hold on shellac and not set up totally hard, but not to mushy? I was experiencing some sort of "cliping" I have come to call those parts that sort of create a quick distortion under the music especially in dance music. I was using one of the diaphragms that had been put together originally with the second choice of glue, which was duco cement. It caused flaking and turing loose of the rings.. Now I am using a sort of all purpose cement that is supposed to stay flexible. It does to a degree, but evidently not enough. When I replaced that outer ring and let the All purpose glue set up a few hours and played it it sound really good. I have a feeling though that tomorrow when the glue has set totally it will effect the sound again? Time will tell. I also changed slightly the width of the piece as I have found a certain range can make a difference in the way it plays. It seems the more firm set of the glue is alright on the inner set, but that outer set must need more ability to move free. That may not be it either, but there was a very obvious feeling of this is it again while hearing it fresh.. It proves I am on the right track, just haven't got every thing to line up in a way that gives the best results. Another problem is I keep raising the bar. At first I accepted small flaws in order to expand the range and tone, but now I don't want any.
Back to the drawing board it seems. After achieving volume, tone and fairly good clarity, at least in some test pieces I discovered yet another flaw that makes me rethink the whole present design layout. I realized that when the mute ball was place in towards the horn that on some pieces a very obvious "clipping" sound that wasn't noticeable with it open became quite aggravating.. I am not sure the reason at this time, well if I knew it I would fix it. I am not sure if its still a glue issue, or lack of enough weight in the center area to prevent it? So I am tying yet another set of pieces using the original hard drying glue, maybe the center can stand that? Also a couple different baffle layouts that eliminate the outer ring, who knows. Heck I may even have to take a break and start looking for different materials. I seem to be reaching a limit on ways to approach the current parts I am using. If only I didn't get such interesting sound at times?
Today was mostly a wash. I eliminated the outer ring determining that it was part of the problem, but after creating and testing a number of varying patterns that didn't use it, only solid layered cores I found that the sound while maybe passable lacked the separation of instruments and tone I had heard in the better of the earlier types. So as a last try I added a very thin outer ring again to a pattern that while workable was rather dull. Darn if it didn't bring back the sound I had before, but it also brought the "cliping" effect that wasn't there much without it.. so I am not sure what avenue to approach it at. Could be that the materials I am using are a part of the problem and maybe some others may not sound or react the same. I have maintained mostly the same items for the past week. I am pretty much out of my prepared shellac coated parts material and may take the day off most of tomorrow. I have yet another try using only shellac as a binder. I tried that earlier but couldn't get it to hold to each other, this will probably be no exception..
I have been putting together shellac coated pieces, with various glues., which is not working well I don't think.. I had earlier tried to get the shellac to act as a glue but wasn't having much luck.. Tonight I again tried a different method of coating each piece and then weighting them down. That is cureing at the moment, I don't know if it is taking or not yet? I also am trying a different layout with that one, who knows.. Then I just tried assembling the pieces without shellac on them and will go back an attempt to coat it after it has been glued paper to paper. I wondered the other day if it might be around the problem. I actually fear though that the distortion I am picking up is more a fault in the design in general than in the way its assembled, but heck, I have tried everything else to get it to work.. Such a shame because when its is working right it is surprising, just can't get the good sound without the little distortions.
Post by lukewarmwater on Feb 9, 2008 0:20:18 GMT -5
Like I said in a previous post, the only glue that completely hardens is hide glue, and epoxies. All other glues remain elastic even when cured. I'm not advocating one over another for your purposes, but the nature of the glues may explain certain results or inability to achieve consistent results. Luke
It may be that hide glue is the only true hard glue, but the effect on the rings is quite different depending on the glue. Some allow a bit more flexibility and others do not. Unfortunately the design depends on the stiffing quality of a glue to hold the more flexible diaphragm part from moving to much and it also helps develop the sound. I have been taking apart with a razor blade some of the pieces to try a different effect sometimes. Some of the flexible glues are just plain gummy in between the two parts. I am not sure if that is a plus or a minus.
I haven't given up but I must admit I am perplexed by problems that so far I just can't solve. I tried and succeeded with using shellac as a glue, and as usual I thought I had the sound I wanted. But after being gone for the day the results were poor again when I returned. That is the biggest problem, how to make a design that works after everything stiffens, which must be the real issue here. Yesterdays success for the moment was an all shellac over paper design with for a while a cork center. It had stunning sound, only to turn into lackluster and buzzy. I was quite surprised when the first try had such volume and depth, clarity, even using the cork which in previous attempts had simply deadened the whole thing. Why was it so loud and so sensitive at first, only to turn sour?
Its a good day when you learn something! Linkage..... I have been following others by using 'Dental floss' for a linkage. That actually works quite well considering it sounds odd. However there are different flosses. I had been using a fairly fine version.. the last diaphragm I had made that used a different layout and shellac as a binder, had its ups and downs. Sounded good only to loose it, then I noticed the floss on it was a bit frayed and the sound noticeably weak. I switched to a different one I had picked up which was thicker or wider. I had tired a piece but rejected it due to too much volume, which with the previous designs seemed to be an issue. But today that somewhat lifeless and still wanting to "clip"as I call it has become Edisonic loud, maybe worse, and 99% of the problem is gone. I can see now why edison used that cork and got away with it, the linkage evidently plays a big part in the power of the diaphragm. I should have known that, but hey, I am a tinkerer at heart and a slow learner. So now I feel once again a little better about this adventure. Gee maybe some of those eariler designs might have worked with this too? I have lots of them laying around, those I haven't pitched.. Now I think I need to add a bit more cork to the center area to calm it down a bit and see what the effect may be. Who knows, some day I won't have to write these. Good thing no one else is writing much here either, might get really long then!