Tube Preamp: How many tubes does it take to .................

It also matters if one is looking to have opportunities to work with the sonic through Tube Rolling.

I know a few individuals who have done this with their Pre-Amps and Pre-Stages on their Power Amp's.

Less is more in this subject area as a Amp' using only a couple of Tubes, is much easier as a preparation task, to attain matched tubes from which era is selected for the tubes production.

Transfer that same preparation to Multi Tube devices and options become diminished quite quickly, unless substantial sums are to be parted with for certain era's of production and follow up testing of supplied tubes is used to identify the measured accuracy of the matches.

It is doable, I am sure I know one person who has 6 x 1960's Vintage ECC 83's in their Amps Pre-Stage.   

@elliotb.  That looks like a vintage Marantz.  Is that from the sixties?

Just because a preamp has multiple tubes doesn't necessarily mean they all have to be matched. I know of a line stage that has 10 tubes in the signal path and only pairs need to be matched.

@elliottbnewcombjr 

Your  McIntosh Tube preamp in picture must be a maintenance nightmare.

I had same bad experience with a AR sp-11 phono/line pre-amp 20 years ago. I bought the unit based on great audiophile commentator Mr. Chen's recommendation.  I was impressed with the phono stage performance. Howerver, very soon, I ran into multiple tube bias issues and component(s) failures. I felt a pre-amp should not require to be baby sitting every 6 months to keep running at optimal state, so I gave it up.

My current  hand made line stage preamp are all single tube stage amplifier based on famous Western-Electric "Ultra path" circuit using best nickel signal transformers and Teflon coupling capacitors, and it out perform AR SP-11 by a big margin.

Furthermore, tube type matters in line pre-amp.  26 direct heated triode sounds best in a cost no limit pre-amp design.

In relation to matching tubes, it certainly is a Horses for Courses subject.

Unfortunately the right horse is not found until tried in the race, pretty much the same for a Tube Roll experience. 

I have had a supply of Brand New Tubes, that when tested, the equipment owner made known immediately one Tube will produce sound, but is with a fault. It was an unknown how such a fault could impact on a circuit, which resulted in the suggestion not to use the tube.

How many individuals are putting New Tubes into their equipment not knowing how it measures on receipt to them, and prior to be put into service.

I have had tube equipment for more than two decades, I have developed my own disciplines, maybe a little cautious, but through careful practices, there is a plan for the usage, that has prevented the worst type of the associated stories occurring so far.