There used to be stories of folks measuring (vertical) resonance directly, by sitting the stylus down on top of an inverted tweeter diaphragm and sweeping. Personally never had the courage to try it because of the magnets issue. But somebody smarter than me (IOW, most anybody) might be able to figure out a workaround.
Thanks,
Chris
Thanks,
Chris
I would think you could measure it by tapping the tonearm or jostling the turntable. You could easily do up to 7Hz by hand. Maybe I'm just ignorant.
Thanks. It will be interesting to see or obtain actual data.
That's just crazy talk! 😀
I would think you could measure it by tapping the tonearm or jostling the turntable. You could easily do up to 7Hz by hand. Maybe I'm just ignorant.
I'm talking about seperating H and V, tapping excites both as well as the table suspention.
I would think you could measure it by tapping the tonearm or jostling the turntable.
So, sit the stylus down on a sacrificial record, tap the arm tube with a pencil, and look at the waterfall plot? Cool!
Thanks,
Chris
edit: I'd need to practice tapping horizontally and vertically.
No, didn't try anything like that, but the slow drop off in quality being "fixed" by pausing was 100% consistent.Im interested in knowing if you go to the last track on every CD vs the first , if you notice a difference ..
Now, in my own delvings, many years ago when the Yamaha player was always the source there was a period when I was trying every permutation and combination in operating the unit - and of course every variation of procedure made a difference, enough to make any sane bloke go mad! Fast forwarding, jumping tracks, waiting, not waiting, remote or not - it was getting ridiculous ... I finally worked out a sequence which was a decent optimum, for that machine, and left it at that. What has been generally consistent, on numerous systems, mine and others, is that pausing for a period is very effective ...
I'm talking about seperating H and V, tapping excites both as well as the table suspention.
Scott, Are you using a VPI unipivot ... ?
What I've found is that if the key, major part of the spectrum is done right then that's all that matters, the mind can adjust for everything else - so above 100Hz, to things still happening at 15k is plenty.At the same time I don't expect a 50 cent speaker to blow my mind, or produce a lifelike sound, just not going to happen with a cheap full range driver. The notion of a full range speaker getting from a modest low of let's say 60hz to 20Khz is just silly, the physics just doesn't compute, you have to give up something somewhere, you can't have your cake and eat it to.This doesn't mean you can't have a pleasant sounding background speaker but I have never heard a full ranger that I would say is truly high fidelity across the entire frequency range.
I don't 'do' background music - with Pete the other night I had to prod him several times to up the volume, 😀, audiophile 'polite' is not my cup of tea. And his system has plenty of "headroom", so no problems there ...
A cheap speaker, driven poorly, from cold, sounds dreadful if you try for some volume. But, if you give the suspension a chance to stabilise, and do the right things it comes to life - produces natural, rich sound which fills the room. Even the PC speakers, which have a tiny, tiny amplifier board can be run cleanly at a level where I, sitting about 15 feet away, no longer can hear any other noises in the house - if the phone rings, too bad ... 🙂
Edit: Pete has DIY dual subwoofers, extremely solid and heavy carcases, but I couldn't 'hear them', 🙂. IOW, they were doing the right thing, filling in the bottom end without drawing attention to their presence, exactly how it should be ...
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Has anyone tried adding a Bybee to a cheap computer speaker? Perhaps it might compensate for the limited bandwidth, high distortion etc. Of course, it might cause the overworked Maxwell demons to go on strike until they are fed better quality electrons from a pure silver wire.
Has anyone tried adding a Bybee to a cheap computer speaker? Perhaps it might compensate for the limited bandwidth, high distortion etc. Of course, it might cause the overworked Maxwell demons to go on strike until they are fed better quality electrons from a pure silver wire.
😀 I've been self enjoined from further contributions along this line.
Scott, Are you using a VPI unipivot ... ?
?? my VPI is just the platter,bearing, motor, and belt. I'm way old school we are probably boreing the masses with this.
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I'm talking about seperating H and V, tapping excites both as well as the table suspention.
Mono swept LF tone on a test record should do it. That's how I'm measuring anyway.
Okay, it sounds like your setup has this behaviour - which doesn't surprise me, every system will have its own, subtle peculiarities. A first guess is that the last track is furthest out from the centre, and the speed of the disc varies depending on the radial positioning; this, and the variation in how the servos are driven to track the groove is enough to alter the electrical interference levels and spectrum being generated, while the disc plays from beginning to end.Howie,
Would this account for the difference in sound between tracks, first vs last for eg..
Right ... Pete, AussiePete on the forum, says no prob's: Rotel RCD991AE with significant mods, caps, power supplies, clock; DEQX unit mixed in with a comprehensive array of Naim amplication, latter with lots of mods, and SKA GB150D's for the subwoofers.Why not clue us in on the rest of the system , what amp type was he running, was the phenom noticed on one disc or all disc, did you compare to see if first track sounds different to last , tracking error..?
Okay, it sounds like your setup has this behaviour - which doesn't surprise me, every system will have its own, subtle peculiarities. A first guess is that the last track is furthest out from the centre, and the speed of the disc varies depending on the radial positioning; this, and the variation in how the servos are driven to track the groove is enough to alter the electrical interference levels and spectrum being generated, while the disc plays from beginning to end.
Frank ,
wacky comments aside , you gotta stop making up these scenario's , did i tell you my system did this , you may have forgotten ( more than an hr) we were discussing your buddy's system with the dodgy digital acting up...
🙄
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My apologies if your digital gear shows no such aspects, I was purely going by the tone of your postings, which implied that you had at least noticed some such behaviour occurring, at some time ... 🙂
Nope , i was merely suggesting it could have been one of the scenarios causing what you heard at Pete's.
The tracking angle problem on LP's can certainly make one aware of such factors - a friend's unit showed this behaviour clearly when he was focusing on maximising the quality, there were clear points of optimum SQ, when the angles were absolutely spot on, which then trailed away on either side of these 'best' positions - that's the sort of thing that would drive me nuts ...! 😀
The fade off of digital quality was fairly generic in earlier years, and I never really noted a positional aspect to it - it depended on how long whatever was running, from hitting the Play button. Lately, things seem to have improved ...
The fade off of digital quality was fairly generic in earlier years, and I never really noted a positional aspect to it - it depended on how long whatever was running, from hitting the Play button. Lately, things seem to have improved ...
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Howie,
Would this account for the difference in sound between tracks, first vs last for eg..
This would be easy to experiment with, by playing the last track first after turn-on, and listening in reverse order...I've never experienced the phenomenon being discussed, so I have no facts one way or the other.
Howie
Howard Hoyt
CE - WXYC-FM 89.3
UNC Chapel Hill, NC
www.wxyc.org
Here a test of sorts burn a song to cd first and then at the inner grove same song with other in be tween for that matter the same song clear across the disc . Given that it is the same equipment doing the transfer then the songs should be all the same . Do it in real time so there is less of a heating problem with this method than at say 16 x . While this test will be berated by all the self appointed pundits as having some flaw it is as far as I know at this time an easy way to test the theory or observation.This would be easy to experiment with, by playing the last track first after turn-on, and listening in reverse order...I've never experienced the phenomenon being discussed, so I have no facts one way or the other.
Howie
Howard Hoyt
CE - WXYC-FM 89.3
UNC Chapel Hill, NC
www.wxyc.org
This a the scientific method of repeatability and verifiability of an experiment not withstanding. Knowing that and knowing this thread it will be ridiculed in some way because it was not their idea . To see what is you must have vision . " Non are so blind as those with sight that have no vision " A quote by a blind man who sailed the atlantic cross alone successfully !
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