How much do I have to amplify a signal to cut?

This is where record cutters raise questions about cutting, and trade wisdom and experiment results. We love Scully, Neumann, Presto, & Rek-O-Kut lathes and Wilcox-Gay Recordios (among others). We are excited by the various modern pro and semi-pro systems, too, in production and development. We use strange, extinct disc-based dictation machines. And other stuff, too.

Moderators: piaptk, tragwag, Steve E., Aussie0zborn

Post Reply
User avatar
amok
Posts: 12
Joined: Sun Jul 03, 2005 12:30 am
Location: chandler, az
Contact:
Contact amok

How much do I have to amplify a signal to cut?

Post: # 371Unread post amok
Sun May 14, 2006 3:58 am

I have 3 Astatic crystal heads and a couple full lathes. The lathes all either have amps that are destroyed (mechanically) or have safety issues.

Basically, I'm looking to cut free of the existing amplification built into these units and having a 1/4" jack feed directly into the cutting head. I've done that but I'm trying to find out how hot my signal has to be to cut something or feel the vibration on the cutting needle. Can you feel vibration at all? I've ran an oscillator through a guitar amp and ran the output to the cutting head. I can't really feel anything there. Just wondering what kind of wattage you guys are cutting with. Are these crystal heads picky about what you feed them? I can't imagine all 3 of my heads are bad.

thanks.
Top

Click Here!

User avatar
amok
Posts: 12
Joined: Sun Jul 03, 2005 12:30 am
Location: chandler, az
Contact:
Contact amok

Post: # 372Unread post amok
Mon May 15, 2006 2:14 pm

Do I need to amplify my signal and then run it through a transformer to step it up?

ANY info would help here.
Top
User avatar
charlief64
Posts: 12
Joined: Mon Jan 23, 2006 4:26 pm

Crystal heads

Post: # 374Unread post charlief64
Tue May 16, 2006 10:45 am

It is almost a given that all three of your heads are bad. The Rochell salts that are in old crystal heads decompose with time. They can easily be rebuilt.

Charlie
Top
User avatar
amok
Posts: 12
Joined: Sun Jul 03, 2005 12:30 am
Location: chandler, az
Contact:
Contact amok

Post: # 375Unread post amok
Tue May 16, 2006 2:15 pm

Yeah. I emailed Gib and he's going to rebuild them.

After they're rebuilt, does it take much to drive the stylus?
Top
User avatar
charlief64
Posts: 12
Joined: Mon Jan 23, 2006 4:26 pm

Driving a crystal head

Post: # 376Unread post charlief64
Tue May 16, 2006 3:21 pm

Crystal heads are pretty efficient. They only need a few watts (under 10) to drive them. The important thing is to match the impeadance. I've only used magnetic heads and don't know what that impeadance is. Gib will know, he know everything. Impeadance matching is pretty easy, you just need to find the right transformer.

Charlie
Top
Post Reply

Click Here!