Mass Deck?
- Thread starter Vinny
- Start date
Mike Reed
pfm Member
Surprised they don't have this exercise down in the Gym.
If you're going to go to mass, Vinny, you'll need to be a bit catholic in your attitude.
Darren L
Egalitarian
No, just turn it off when you're not using it.
Thanks.
OK, how simple is it really to get a stable speed? I suspect that there is a problem with the motor.
I listened to 3 LPs this morning and all seemed OK. This afternoon, I put an LP on that had sounded odd previously, something that just happens to highlight speed inaccuracy as it turns out - Depeche Mode - Ultra.
I have started it twice in succession now and it has stabilised at 10 revs per 15 seconds - 40rpm. Watching a strobe sheet for more than a short while has your eyes going odd, but it appears to be running fast, but hunting - this is over a few minutes continuous running.
I have altered the position of the motor to change belt tension and that looks to have little or no effect.
PITA or what? The oddest thing is the fast rather than low speed.
OK, how simple is it really to get a stable speed? I suspect that there is a problem with the motor.
I listened to 3 LPs this morning and all seemed OK. This afternoon, I put an LP on that had sounded odd previously, something that just happens to highlight speed inaccuracy as it turns out - Depeche Mode - Ultra.
I have started it twice in succession now and it has stabilised at 10 revs per 15 seconds - 40rpm. Watching a strobe sheet for more than a short while has your eyes going odd, but it appears to be running fast, but hunting - this is over a few minutes continuous running.
I have altered the position of the motor to change belt tension and that looks to have little or no effect.
PITA or what? The oddest thing is the fast rather than low speed.
sq225917
Bit of this, bit of that
Vinny if the belt is slightly oversize and you set it for 33 when you switch to 45 it'll likely be faster than 45.
Its to do with the belt centre ratio effectively making the larger 45 pulley appear larger than the physical ratio of the two bits of pulley actually are.
Its to do with the belt centre ratio effectively making the larger 45 pulley appear larger than the physical ratio of the two bits of pulley actually are.
sq225917
Bit of this, bit of that
You should read the thread about belt thickness on diyaudio.com, there's some crazy back n forth on it from people with really entrenched views before one guy comes on with the math to prove that its not just pulley diameter, but pulley and belt that counts, round or flat. Typical audio thread...
Mike Reed
pfm Member
Or eventually wear the bearing out; at least induce the need to clean it out and refresh the oil, plus belt wear etcetera.
Vinny, does your power supply have adjustment as I don't think it's the Wave Mechanic? Not sure if this is as feasible with a 9" arm, but I put the edge of the cart. over the strobe markings so that the little lines are easier to establish if fast or slow. I point the zapper down to illuminate the strobe and adjust the power supply accordingly.
I was thinking more of the platter stationary, left on. With no power switch, it is rather different to most kit - until recently I just switched everything off on the switches, but that obviously doesn't work with NA decks.
No speed adjustment, until/unless I can rustle-up a s/h wave mechanic - 90% of the hassle is just me getting used to the deck, Mike.
I'll go back o the LP12 after a few days, but I strongly suspect that it won't be for long.
No speed adjustment, until/unless I can rustle-up a s/h wave mechanic - 90% of the hassle is just me getting used to the deck, Mike.
I'll go back o the LP12 after a few days, but I strongly suspect that it won't be for long.
JensenHealey
pfm Member
I found that thread quite amusing at the time.
Somebody's maths was rubbish or very highly inventive though. No, not tracked it down.
Replace pulleys with sprockets and a belt by a chain - exactly the same principle, just one is all but slip-free. Changes to the chain produce what effect on drive speed/ratio?
Slightly different for a round belt running in a near size groove - under-sized belt, no change, over-sized and it will run high in the groove, increasing linear speed of the belt.
Consult some very simple engineering design/problem-solving websites and speed variation with belt design/size, apart from slippage and wear, gets no mention.
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Well, it is official - the better half has been away for a while, but she was mightily impressed (as she was with changing the felt mat for 3 very small blobs of sorbothane on the LP12, it has to be said).
Thanks to @Mike Reed and @Darren L in particular for their patience and comments.
For the record - current spec' Hyperspace, 10 inch Anna and Delos.
Room for improvement, sometime, maybe - 12 inch tonearm and a wave mechanic.
Thanks to @Mike Reed and @Darren L in particular for their patience and comments.
For the record - current spec' Hyperspace, 10 inch Anna and Delos.
Room for improvement, sometime, maybe - 12 inch tonearm and a wave mechanic.
Mike Reed
pfm Member
Thanks Vinny. Lyra with unipivot = synergy. Delos = best bang for buck in the range. You now have a specific upgrade path which doesn't cost a fortune (used). Even the Lyra is worth 25% of another Lyra as trade-in.