MaxiMatcher 2 and MaxiPreamp 2 tube testers

[jdandy]

My two new digital tube testers finally arrived after taking the 20 mule team route for delivery. The MaxiMatcher 2 is a power tube tester and the MaxiPreamp 2 tube tester is a small tube tester. Both are well built units that come in their own hinged cover cases. They each weigh about 14 lbs.

I got right to it and tested all of my KT88 tubes, all 36 of them. I was surprised to discover the Gold Lion KT88 I thought was defective was fine, no internal shorts and tested well for plate current and transconductance. After testing all the remaining Gold Lion KT88's, including the four new ones that just arrived, I reinstalled the suspect Gold Lion KT88 back in the same socket in the MC2301 amplifier and it has been playing perfectly all afternoon. I have no idea why I saw a flash in the tube and the McIntosh Sentry Monitor circuit shut down the amplifier, but all seems well so far.

I also tested all of my small tubes, 12AX7's, 12AT7's, ECC83's, and ECC801S tubes. All of them tested very strong and closely balanced. This gives me confidence that the tubes I am using, as well as the tubes in my locker, are in good shape and ready for immediate use. I have yet to pull my C2300 out of the living room rack and test the Telefunken's in the phono stage and the Gold Lion's in the line stage but I will get to that shortly.

It is a pleasure to finally own tube testing equipment that allows me to know the state of my vacuum tubes. Guessing just doesn't get it when it comes to tubes, especially power tubes. Both the MaxiMatcher 2 and the MaxiPreamp 2 are easy to use, well engineered, and solidly built testers that I am positive will last me for many years of service. I can recommend both of these testers to any vacuum tube audiophile.


MaxiMatcher 2





MaxiPreamp 2

[Ritmo]

Very cool Dan!

[Jerome W]

That is Great Dan ! Congrats !

I have been thinking of buying one of these since a long time but I do not think that I will have the skills to fully understand what it says

[MyPal]

Congrats Dan!...Nice!

Keep an eye on that flashy KT88....Does the MaxiMatcher allow you to run tubes for extended durations or testing cycles? Perhaps the suspect KT88 tests OK during a standard test cycle but could be unstable after a longer run times....

[jdandy]

Originally Posted by MyPal

Congrats Dan!...Nice!

Keep an eye on that flashy KT88....Does the MaxiMatcher allow you to run tubes for extended durations or testing cycles? Perhaps the suspect KT88 tests OK during a standard test cycle but could be unstable after a longer run times....

Steve.......The MaxiMatcher does allow extended tests. You can leave the heater and plate current on as long as you wish, then with a switch you can read transconductance or plate current. I let both of the KT88's I removed for 20 minutes without incident. They were at full operating temperature as well. I tested both of the tubes in the short circuit socket on the tester with no issues shown. I will keep my eyes and ears on this amplifier until I feel comfortable. I have been playing the studio system for the past 10 hours and all is well.

[jdandy]

Originally Posted by Jerome W

That is Great Dan ! Congrats !

I have been thinking of buying one of these since a long time but I do not think that I will have the skills to fully understand what it says

Jérôme.......These two tube testers are simple to use and understand. You do not have to be a electronics tech to understand the function and results. The operating instructions come with the MaxiMatcher 2 power tube tester and the MaxiPreamp 2. Owning tube amplifiers makes owning tube testers essential. I am very pleased I finally took the leap. These test instruments will sit idle most of the time but when you need them they are priceless for the peace of mind they provide.

[Jerome W]

Originally Posted by jdandy

Jérôme.......These two tube testers are simple to use and understand. You do not have to be a electronics tech to understand the function and results. The operating instructions come with the MaxiMatcher 2 power tube tester and the MaxiPreamp 2. Owning tube amplifiers makes owning tube testers essential. I am very pleased I finally took the leap. These test instruments will sit idle most of the time but when you need them they are priceless for the peace of mind they provide.

That was also my initial thinking Dan, especially because I own so many tube components.
But I read that when a tube tests very well, it does not mean that it could not fail one hour later. If this is true, then a tube tester is only useful to check if the tubes are matched no ?
On a side note, the tube you removed from your 2301 was flashing in the amp and tests ok on the tester ? Am I correct ?

Sent from my iPad using A.Aficionado

[jdandy]

Originally Posted by Jerome W

That was also my initial thinking Dan, especially because I own so many tube components.
But I read that when a tube tests very well, it does not mean that it could not fail one hour later. If this is true, then a tube tester is only useful to check if the tubes are matched no ?
On a side note, the tube you removed from your 2301 was flashing in the amp and tests ok on the tester ? Am I correct ?

Jerome.......Yes, it flashed once and the MC2301 shut down. Of course I did not turn the amplifier back on until I had replaced the suspect tube, but after testing it for shorts I felt comfortable enough to reinstall it. It has been performing perfectly since then. Without the tube tester verifying that the KT88 was not internally shorted there was no way I would reinstall that tube. Once it tested clean and had equal plate current and tranconductance numbers to the other KT88 tubes, I was confident enough in those results to give that tube a second try. Without the tube tester I would have tossed the tube in the garbage. Who knows, maybe it will give up the ghost prematurely, or it may operate fine for a couple thousand more hours. Only time will tell. If the MaxiMatcher had shown it to be defective it would not have been put back in service.

Another thing tube testers are good for is checking the life left in a tube against a new tubes plate current and transconductance numbers. When I tested brand new Gold Lion KT88's against the 16 with 760 hours on them I was able to note the lower plate current and transconductance numbers of the older tubes, while at the same time verify that these tubes were still well within the good range.

You are correct that a tube can be reading good and then fail in the next hour. One really has no control over that. It is the nature of vacuum tubes to have some that fail prematurely AND without warning. Tubes are hand made one at a time so quality will vary from tube to tube by some measure of degrees.

[MyPal]

Jerome....a tester is essential if you want to guarantee that your tubes are matched & performing within the published specification tolerances. As Dan pointed out, tubes decay over time & the decay rate can vary individually. So over an extended period, your matched tubes can become mismatched.

Apparently later generation McIntosh amps are very forgiving & have auto bias adjustment.

[Jerome W]

Ok guys,

I understand now.
I really need one.
Thanks a lot.