[bbird1927]

Hi, i am new to tube amp. Just ordered a Little Dot MK III.
I am looking for some tubes online (thinking of upgrading already

), the price difference between "Matched pair" tube vs "Random/unmatched pair" is quite significant.

Just wondering Is tube matching necessary (for Driver Tube)

Googling result concluded that tube matching is important for power tube, but doesnt contribute much for driver tube/pre-amp tube.

Any input ?

Thanks

 

[bbird1927]

No one ??

 

[Skylab]

The short answer is that in general, it's desirable to have matched tubes, and in dual-triodes, matched sections. But exactly HOW valuable is very tough to answer. It depends on several factors, like what type of tube and how it's used, etc. There isn't an easy answer to this question.

But even more, there is the issue of what "matching" means. If the person (an EBay seller, for example), says that the tubes are matched, how was this determined? If what they are reporting is that they tested the tubes on an emissions tester and the numbers were the same, that may be nice, but it doesn't really provide any solid electrical information about the tube, and as such, really doesn't make the tubes "matched" in the way we would want them to be.

If the tubes were tested in a tester that can actually test mutual transconductance, however, for an audio tube this can be a useful measurement. The transconductance of a tube is one factor in determining what the tube's amplification factor is. If you have two tubes of the same type, say a 6SN7, that have wildly different transconductance, and let's say there is one 6SN7 per channel, and that they are very, very badly matched, you could get an imbalance in the channels, which could be annoying. But the tubes would have to be quite poorly matched indeed for this to be an issue in most amps.

A rectifier tube with poorly matched sections can potentially also cause problems, but that's an even longer story.

Bottom line - matching is good. But it's usually not crucial.

 

[atbglenn]

I purchased many tubes for my woo 6 from ebay, none of them electrically matched other than brand and vintage. I've never noticed any imbalance, or any difference in SQ between right and left. I think in most cases it doesn't make a difference.

 

[david1978jp]

Let's say now you have a perfect pairs, but tubes don't necessarily age at the same rate...
Your ears know you what you like. If it sounds good, then it's good.