. . . its a picture, go to the next post . . .
OK . . . brought about by talking to Jeff Spell of Audiomods, with referance to the new arm orderd. Jeff seemed to think it was worth a try to increas the mass of my Sumiko Pearwood/Northwest Audio cartridge . . . ? In his work on developing the Audiomods arm MC cartridges have, on occassions matched better by adding mass. Ok I said, what is your sugestion, "we do a set of 3 headshell mass shims, I'll send you a set you can try them", said Jeff
Arived a couple of days later, that was a couple of weeks ago . . . the brain had gone into over drive by this time :wall: so I poped them in the draw, wait, not in the best of receptive moods.
. . . Started the thinking process again, talked to Jeff again, sitting with not a lot to do. He had sugested I could put the shims on the top of the headshell with a tiny blob of bluTack, saves the hassel of re aligning the cartridge. OK, I can set the balance spot on with the new digital scales, no more guess work.
Everything to gain nothing to loose . . . gay abandon into 'tweakery' :bounce: . . . The shims weight 2.4gs, 5gs and I guess 9gs, my scales dont go past 5gs. Jeff sugested the ligtest mass shim for the Sumiko, I put three tiny 'pin head' size blobs of BluTack, 3 is more stable than one. Sceptical??? but as I dont understand the 'compliance/arm matching mathamatics', I go on advise and what my ears tell me. For those that want to, the Sumiko weighs 7gs, has a compliance of 12 x 10.6.
I'm listening now, the obvious diference is a tiny improvement in the inner detail, with a smoother presentation, the unexpected suprise is an even quieter noise floor. My feeling is the light shim is doing a job worth pursuing, the interesting bit will be when I get my new 'AM Classic arm' . . .
Our finding are a work in progress, Hazel agees with me, she prefers the smooth presentation which seems to offere tiny bits of extra detail, waiting with anticipation . . .
I understand these differances are small, not worth the effort to many, however my mantra has always been; 'the sum of the parts . . . etc' , and I can always back track' . . . part of the fun :cheers:
As you say CJ , use your ears. All this compliance mullarky is pretty much old hat . Most modern MCs are quite happy with a medium mass tonearm , manufacturers learnt well. They had to if you think about it !. There are obviously a few odd ball carts out there, which certain reviewers decided would be a good idea to bolt onto an RB300 , despite being forwarned that they wouldnt work all that great , which they didnt ! ,idjuts. So yeah use your lugholes mate.
Had a bit more playing at 'Tweakery' today, yet another landmark . . . amazing how the simple things in hifi can work so well . . . :shhh:
Just out of idle curiosity, what do these small pieces of metal retail for?
The_Lhc wrote:Just out of idle curiosity, what do these small pieces of metal retail for?
I thing they are around £20 the set. Not cheap on the face of it but the potential I am discovering as I work with them, I am getting more from them than speaker cables I have tried at £50pm . . . so good value IMHO.
Oh ok, better than I expected really.
Yip not so bad considering its TT related. Another out of interest question CJ , bit tough for me to see properly but I'm guessing that they are pressings and not individualy machined ?.
floyd droid wrote:Yip not so bad considering its TT related. Another out of interest question CJ , bit tough for me to see properly but I'm guessing that they are pressings and not individualy machined ?.
Hi Floyd, they are laser cut. The two heavier shims are annealed copper, the third lighter one feels like a hard aluminium?
I'm trying to think of a way to describe the changes/improvements I am expriancing with out writing an epistle or sounding like a boreing geek? . . .
This isn't tweakery, mate, it's solving a problem - the compliance of your cartridge isn't perfect for the mass of your arm, which introduces resonance in the audible spectrum, so you add weight to the arm. You'll find plenty of stuff on this if you check the web.
Now have a headache, haven't though of this stuff for years.
altruistic.lemon wrote:This isn't tweakery, mate, it's solving a problem - the compliance of your cartridge isn't perfect for the mass of your arm, which introduces resonance in the audible spectrum, so you add weight to the arm. You'll find plenty of stuff on this if you check the web.Now have a headache, haven't though of this stuff for years.
Exactly altruistic.lemon, it gives me a headache trying to understand the maths . . . so I do it my way and listen, the differences, in this case are so obviuse and 'better'; dont use 'better' lightly. We dont seem to worry about compliance/arm match in the UK like they do in the US? or am I missing something?
There's a site somewhere that does it automatically for you somewhere, mate. Wouldn't know about the US.