richardkrebs

Responses from richardkrebs

Direct Drive vs. Idler Drive vs. Belt drive
@totem395 Yes it goes without saying that the drive can manage an apparently stationary dot over 1.8 seconds. I was referring to a longer time frame, say a complete side of an LP. To me it doesn't really matter if the dot has drifted a little afte... 
Direct Drive vs. Idler Drive vs. Belt drive
Mike.Many thanks for the invite. There is a little problem of distance however, since I live in New Zealand.I do not disagree with you at all re the signature of "most" DDs. I spent 15 years whittling away at my mk3, little by little mitigating th... 
Direct Drive vs. Idler Drive vs. Belt drive
An update to my last post. A point I didn't make clear. The change in angle between the  rotating field and the rotor due to dynamic changes in load is a momentary change in platter speed. It is measurable and audible. Over time the average speed ... 
Direct Drive vs. Idler Drive vs. Belt drive
Lew.The problem is not the motor it self making noise. This assuming the designer has used a good one. The problem is the interaction of the controller/ motor/ platter feed back loop.IMO the designer should use what I call a very tight motor. I me... 
Direct Drive vs. Idler Drive vs. Belt drive
Mijostyn.Correction to my earlier calc, for those of you looking at my numbers.The original distance would be 4.63mm, where plus 10mm gives a 10 fold reduction in field strength. Still a physical impossibility. Apologies, for my typo. Cheers.  
Direct Drive vs. Idler Drive vs. Belt drive
mijostin  I would offer the counter view. It is far harder to build an acceptable DD than BD for the reasons I noted earlier in this threadFurther with respect to the distance from the source, as you say the inverse square law applies. Double the ... 
Direct Drive vs. Idler Drive vs. Belt drive
In a synchronous motor the rotor lags behind the rotating field. This angle changes with changes in load There are subtle differences between motors, even with apparently the exact same build. This results in slight differences in this lag angle f... 
Direct Drive vs. Idler Drive vs. Belt drive
has2bePeacecheers  
Direct Drive vs. Idler Drive vs. Belt drive
has2beI was merely (re)stating an inherent advantage of a DD design with respect to its bearing, after all the OP has asked this....."I'd like to know your thoughts on the strengths and weaknesses of each drive system"I did not say that overall DD... 
Direct Drive vs. Idler Drive vs. Belt drive
Yes, this is an advantage of a DD drive that is often overlooked. There is no horizontal force induced by a belt, thread, tape or idler wheel.There is a toppling force if the thrust point is at the bottom of the bearing but this should be easily a... 
Tonearm mount to the plinth vs arm board vs rotating arm board vs isolated tower
Atmasphere"Or you could use a mirror mounted on the item under test, a laser and a sound source to demonstrate how a separate arm pod will not vibrate the same as the plinth onto which the platter is mounted, even if both use the same construction... 
Tonearm mount to the plinth vs arm board vs rotating arm board vs isolated tower
CoolHow much weight can the Herzan carry?Cost?Self noise generated by the action of playing a record.What do we do with this energy?Sink it, dissipate it in the TT structure, both. Cheers  
Tonearm mount to the plinth vs arm board vs rotating arm board vs isolated tower
Halcro.Quite a number of people have reported on the efficacy of the Herzan stands and their equivalents.Out of curiosity what do the three graphs, V, H1 & H2 represent? Velocity and frequency?How does the stand reduce self noise in the TT str... 
Tonearm mount to the plinth vs arm board vs rotating arm board vs isolated tower
Yes, while Mark and I have taken significantly different paths in our designs, we both agree on the fundamentals. We just approached them from different perspectives. 
Tonearm mount to the plinth vs arm board vs rotating arm board vs isolated tower
I echo Lewm's comments re the Helix TTs.Mark Doehmann's design is innovative and unique. Way cool. I have heard them a number of times and they are exceptional. I have also met Mark twice. He is totally open to sharing his extensive knowledge abou...