Hi all, can someone explain the mechanism of the arm tracking of this turntable? How does the turntable feel that the arm moves and what does it do? ( sorry for my english :-)

Thanx

Loris

It's an optical mech. inside the carrriage housing, electronics on the main board and a servo motor with a belt drive.
A lamp, an interrupter and an LDR sits inside the carriage housing. The interrupter is swung into the light beam as the tonearm is
moved sideways, it interrupts the light that falls on the LDR (Light Dependant Resistor).
Based on the resistance of the LDR, the electronics command the servo motor to adjust accordingly.

Martin

Thanx Martin. I asked this because I put a new smmc4 in my 5005. I was listening a record and in correspondence with deep basses I heard some crack sound: every strong bass one crack. I thought it was the transport but visually it was ok, it wasn't a groove skip. I tryed the HI FI NEWS test record, and the tracking was very bad. I had to raise the tracking force till 1,7 g for getting a decent tracking. I'll do the break-in with this weight, and after some hour I'll see if I can lower the tracking force.

Loris

How did you measure the tracking weight? Remember the scale on the arm may not be completely accurate with a Soundsmith cartridge - I always use a cartridge balance to get about the correct weight and then tune by ear. A little more weight is better than too little.

Thanx Peter.

Actually I just used the 5005 scale. I didn't think the smmc weight could be different from b&ommc. If it's lighter I have to go up on the scale.  Do you know these cartridges are lighter? I'll try to use a balance.

I can't put the balance under the stylus, there's not enough space ( in hight)

I measured the weight: it's 1,4 g. ( 1,7 on the scale of the arm).

I guess it's ok to leave this weight.

Loris