AC v DC Motors

Hi All,

Well after my question earlier in the week I am still not sure whether to take the plunge and swap the LP12 motor for a DC derivative. Going for somethine akin to the Origin Live upgrade is going to be quite expensive. The other alternative is to stick with the AC motor and improve on the existing Valhalla supply with maybe a Linn Lingo or something similar. The concern about the DC option is that if its so good why do people like Linn still use AC motors? Are there any other options besides the Lingo (which I can imagine is expensive) for driving the AC motor from other manufacturers? Thanks for any advice or opionions.

M
 

EC8010

Ex-Moderator
2003-01-18 7:57 am
Near London. UK
I rather suspect that there's a very simple reason for the switch to DC motors. Once upon a time, central heating and inductrial controllers were implemented by mechanical clockes driven by synchronous motors knocking mechanical switches (no, really, they were). Now it's all done with silicon so there's no need to make synchronous motors. Even in its heyday, the Hi-Fi industry was very small, and has always existed off scraps off the table of bigger industries.

Oh, and by the way, all motors are AC. It's just that the "DC" ones have a rotating switch (commutator) to internally turn the DC into AC.

Welcome to the forum!
 
AC motors lock on to frequency which guarantees absolute speed accuracy and makes life easier. With DC you need some kind of feedback to verify speed - either your eyes with a strobe disk or some feedback control system.

Why do Linn stick to AC? For the only reason, i suspect, that it allows them to sell the ludicrously overpriced Lingo. A diy Lingo simply cannot cost more than $100 to build.

I like building Valhalla/Lingo type circuits but my next TT will definitely use a DC motor. A friend of mine recently upgraded his Linn with an Origin live generic dc motor. It cost him about $280 and he seemed absolutely delighted with the result. I suspect it is a $20 motor with a $260 pulley but as long as it betters the Valhalla...