Construction matched pair?

[Emil]

What exactly does that mean?

http://www.ebay.com/itm/like/351939880390?dest=http%3A%2F%2Fwww.ebay.com%2Fitm%2F351939880390

[richidoo]

A phrase made up by Ebay seller 'bobvcs'


http://www.ebay.com/itm/Construction-Matched-Pair-Raytheon-Triad-12AZ7A-NOS-NIB-Tubes-combine-ship-/351946427801

[tmazz]

If you look at his other ads he has quite a few  that show photos of two tubes from different brands that are call construction matched. From what I can gather from the photos and his descriptions it seems that he is using the term "construction matched" to describe tubed that from a visual inspection point of view look like they have the same internal plate structure.

Back in the day it was quite common for a given tube manufacturer to build large batches of tubes and sell them to other tube companies to label and sell under their own brand. I think the implication that is being made in these listings is that since the tubes look the same, they are identical. To me this, even if true is rather irrelevant. A) just because the plates look the same when viewed from the outside this does not guarantee that the plate structure you cannot see on the inside is identical, B) even if the plate construction is the same, nothing says that all of the materials are the same, or of the same quality and C) the whole process of matching tubes is used to find pairs that perform the same on an electrical basis. This is usually done within batches of tubes that are labeled and source from the same company. If you have an application that requires tubed , even from the same production run be culled and matched, what would make you think that two tubes from two different sources would have identical specs?

To me is this just a bunch of marketing BS aimed at people who don't know any better, or at least don't know enough to asked some people who know more about tubes.

[StereoNut]

In the immortal words of Frank Sinatra

"Tubey - doobey - do!"



SN

[tmazz]

What exactly does that mean?

http://www.ebay.com/itm/like/351939880390?dest=http%3A%2F%2Fwww.ebay.com%2Fitm%2F351939880390

Emil, I guess the bottom line of my explanation was to me, it it provides no information that could be of any value to us as audiophile.

[Emil]

What exactly does that mean?

http://www.ebay.com/itm/like/351939880390?dest=http%3A%2F%2Fwww.ebay.com%2Fitm%2F351939880390

Emil, I guess the bottom line of my explanation was to me, it it provides no information that could be of any value to us as audiophile.

at least don't know enough to asked some people who know more about tubes.

Oh thats not me. I did ask those who know more about tubes.

[tmazz]

What exactly does that mean?

http://www.ebay.com/itm/like/351939880390?dest=http%3A%2F%2Fwww.ebay.com%2Fitm%2F351939880390

Emil, I guess the bottom line of my explanation was to me, it it provides no information that could be of any value to us as audiophile.

at least don't know enough to asked some people who know more about tubes.

Oh thats not me. I did ask those who know more about tubes.

...and that's why we all hang out here.