Audio Note UK vs Audio Japan Sonic Differences

[mtemur]

When you say you don’t think there is any difference between the triple mica and five-star, you mean sound-wise, right?

The URL I attached shows a massive difference in the construction. Differences including five mica in the five-star (paired-mica above and below the plates =4 mica + additional getter shield mica at the top =5 mica) and gold or silver plated grids. It also speaks of holes in the mica, thyratron welding, other including the five-stars being built in a completely separate factory space to all the others GE made.

I don't think there is any difference between GE 5-star and regular triple mica, square getter 6072 tubes from the same era, around 1954-1958. They're identical both sound wise and construction wise. I mean General Electric 6072 tubes not the other brands.

AFAIK there are only 2 or 3 micas inside small signal double triode tubes. Never heard of 5 mica GE 6072 and I don't think they exist. I can tell you that it's a GE 6072 square getter before 1959 by looking at the inner parts of the tube at the page you shared. Some have support posts and small plates between posts that separate second and third micas as the one in the pictures but it is not consistent through all the GE 6072 tubes.

Specifications, advertisements, brochures may tell a different story but one thing is pretty consistent with GE tubes, especially with 6072s. They are unreliable. It's advertised that they're sturdy, mil-spec tubes and have 10.000 hrs life span but my experience tells the other way. They fail more than any small tube that I ever used. I'm damn sure about it.

1950's GE triple mica 6072 tube means: expect to deal with differences between triodes, be prepared for a tube failure, stock many of them etc. Unfortunately there is no alternative.

 

[Rensselaer]

I don't think there is any difference between GE 5-star and regular triple mica, square getter 6072 tubes from the same era, around 1954-1958. They're identical both sound wise and construction wise. I mean General Electric 6072 tubes not the other brands.

AFAIK there are only 2 or 3 micas inside small signal double triode tubes. Never heard of 5 mica GE 6072 and I don't think they exist. I can tell you that it's a GE 6072 square getter before 1959 by looking at the inner parts of the tube at the page you shared. Some have support posts and small plates between posts that separate second and third micas as the one in the pictures but it is not consistent through all the GE 6072 tubes.

Specifications, advertisements, brochures may tell a different story but one thing is pretty consistent with GE tubes, especially with 6072s. They are unreliable. It's advertised that they're sturdy, mil-spec tubes and have 10.000 hrs life span but my experience tells the other way. They fail more than any small tube that I ever used. I'm damn sure about it.

1950's GE triple mica 6072 tube means: expect to deal with differences between triodes, be prepared for a tube failure, stock many of them etc. Unfortunately there is no alternative.

Are we looking at the same photo? I can clearly see a horizontal line showing that the upper and lower micas are actually two micas together at each site. Doubled for extra strength. The mica under the D-getter looks to be just one however.

I ask then would others following this thread have a look at the article I attached to my posting (#354) and tell me if you see just one mica wafer at three sites, or pairs of micas pressed together above and below the plates and another (5th) single mica under the D-getter up top. In addition, read the rest of the article on how GE made their 5-star 6072s in a completely separate factory with better parts (silver/gold-plated grids) and much more stringent build standards and vote whether you believe this fake or accurate.

 

[mtemur]

Are we looking at the same photo? I can clearly see a horizontal line showing that the upper and lower micas are actually two micas together at each site. Doubled for extra strength. The mica under the D-getter looks to be just one however.

It is always like that. That's how a triple mica tube's construction looks like. There is no such a thing like 5 mica 6072 tube AFAIK.

 

[Rensselaer]

It is always like that. That's how a triple mica tube's construction looks like. There is no such a thing like 5 mica 6072 tube AFAIK.

What does AFAIK mean?

 

[mtemur]

What does AFAIK mean?

as far as I know