2. analog
  3. 1317949815

Vintage DD turntables. Are we living dangerously?

I have just acquired a 32 year old JVC/Victor TT-101 DD turntable after having its lesser brother, the TT-81 for the last year.
TT-101
This is one of the great DD designs made at a time when the giant Japanese electronics companies like Technics, Denon, JVC/Victor and Pioneer could pour millions of dollars into 'flagship' models to 'enhance' their lower range models which often sold in the millions.
Because of their complexity however.......if they malfunction.....parts are 'unobtanium'....and they often cannot be repaired.
halcro
totem395
390 posts
 

Thuchan
What is the disadvantage of stand alone armpods and why is it crucial that there is a connection between armpod and table?

This subject was a bone of contention here previously with the Train
analogy front and center. I will leave it at that.
fleib
1,124 posts
 
If the table has a suspension it's necessary to have the arm move with the platter.

If there is no suspension the advantage of a subchassis (structure that connects arm pod to the main bearing) is convenience. The disadvantage is, vibrations are usually more easily transmitted from platter, and possibly motor, to the arm.

Maintaining a fixed relationship between arm pod and platter makes it easier to keep mounting distance accurate, especially when swapping arms. Armboards can be cut based on that fixed relationship.
dover
2,337 posts
 
Thucan -
it is very simple.The stylus is measuring the groove. To accurately measure the groove the platter and arm board must maintain a constant relationship. They must be rigidly coupled via a close loop system to ensure there is no differential movement between the two. Imagine trying to measure the length of a piece of wood with the 0 point of the tape moving back and forth.

A similar case can be argued for having a rigid closed loop between the motor and platter. Physics tells us that where a platter/arm are not rigidly coupled to the motor drive, then there will be speed instability. Examples are
1) Where people put TT's on air platforms and the motor is on another table
2) The motor is mounted on a chassis and the platter/arm are mounted on a suspended suspended sub chassis.
thuchan
1,009 posts
 
Totem395,
you`re right. Maybe I was asking too much in general. I am not referring to the theoretical implications. Copernicus should blame me. I thought in the meantime there could be some more experiences from experimenting rather than describing why one belongs to the stand alone camp or related camp, no? Everyone is proposing only THE ONE SOLUTION?

Back to the practical side: I am experimenting with stand alone and related implementations. For my 100M I am just building a very massive stand alone pod and I`d like to find out if it really makes a difference when the pod is related to the Denon or not (in case I am suceeding doing so)?

For the 101 I am attracted by Henry`s pod design. Only my EA-10 will not fit into one of the pods due to its large counter screw.

Another idea is building a massive substructure for the 101, precisely drilling a 40 mm high and 400 x 400 mm massive aluminum bases (like with the MS RX 5000) and incorporate four related arm pillars at all four corners similar to the Micro Seiki`s ones. In the middle of the bases I could carve out a 5 mm deep recess taking up the Victor thus fixing the 101, not moving around from this position.

When done properly by using 30mm steel knobs and original 20mm MS bases I have no problem using cantilevered armboards. In this implementation the pods would be related. I am not decided yet. Any ideas?
thuchan
1,009 posts
 
thanks Fleib and Dover - very helpful indeed!
what do you think about the two implementation designs I mentioned above?
More to discover