LD cutter head info

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All85
Posts: 11
Joined: Thu Apr 17, 2014 10:04 am

LD cutter head info

Post: # 49167Unread post All85
Tue Jan 30, 2018 6:57 am

Hi Trolls.
i started my passion about lathe cut not so far so i need your help;) i m owner of a beautiful 'Le Dauphine' old cutter machine.
It spin and all seems to work good!;)(i ship cutter head to gib years ago to be sure that it works;).

I try to emboss on plastic (as i do on other Meissner lathe) but quality are lower, sound is very very softly!!!

I m driving it with a RCF .PA amp AM7030 with 70v line out.
Do you think is this amp wrong?

Are Transistor amps wrong to drive cutter coil head?

Someone could tell me more about spec or correct amp?

Thanks a lot

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fredbissnette
Posts: 383
Joined: Tue Oct 11, 2016 5:38 pm

Re: LD cutter head info

Post: # 49169Unread post fredbissnette
Tue Jan 30, 2018 11:03 am

dont drive it with 70v drive it with the 8ohm or 16 ohm taps
Instagram @styluspressurerecords

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markrob
Posts: 1623
Joined: Wed Nov 28, 2007 1:14 am
Location: Philadelphia Area

Re: LD cutter head info

Post: # 49170Unread post markrob
Tue Jan 30, 2018 1:18 pm

Hi,

Fred is correct if the head is a low impedance type. If its a 500 ohm or similar, then the 70.7V output might work. To be sure, measure the DC resistance of the head. If its under 16 ohms, then a direct drive from a solid state amp would be correct. If its in the 100 ohm and up range you either need to use the 70.7V output or use a matching transformer. If the head is a crystal type, then you need an even higher voltage drive to get the head moving. In this case, you will either need to drive directly from the plate of the output amplifier tube or get a step up matching transformer of the appropriate type.

Mark

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