Orange Valve Tester Mark II - My experience (so far) on how it fares against other matchers/testers?

  • Thread starter Thread starter War_in_D
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The Valve Tester Mk2 is still the best investment I made last year.
Works perfect for me. I've found worn or microphonic tubes in most of the used amps I've bought,
and a simple tube change turned them into fire-breathing beasts.

Best example: PRS MT100: bought used-mint condition, amp sounded ok, I found 4 microphonic preamp tubes,.
Changed those tubes, broke them in, and the amp just SHINES. You can get lost in each channel for hours.
That's just one example of many.

If the Valve Tester is not working for you....it's user error

You don't tap the tube and get a number.
RTFM

The only anomaly I've found is that KT77s only read with the EL34 test (KT77 Test will give you fail)
 
FLUXX said:
If the Valve Tester is not working for you....it's user error

You don't tap the tube and get a number.
RTFM
Click to expand...

You absolutely do tap the (preamp) tubes. That's part of a microphonic test in an amp and in the valve tester. I took your advice to "RTFM" and from the manual, page 16:

"...tap the valve gently with a pencil to test microphony. Note: If there is any noise present in the valve some LEDs will illuminate prior to tapping."

They even include a branded pencil with the device with which to tap the tubes. It's not user error. The tester just isn't very good. That's why there's hundreds, if not thousands, of posts around the internet from users complaining about it. That's why they came out with a MKII in an (unsuccessful) attempt to address the issues with the first version.

I measured voltages on every pin while the unit does tests. During the microphonic test, plate voltage spikes to 220v and then slowly drops below 198v. That's why you get a spike on the LEDs at first and then it slowly drops to below zero. This causes tubes that ARE microphonic at actual guitar amp voltages to appear non-microphonic once the voltage drops. Then you tap the tube to see if mechanical microphony exists. The tester is janky though and inconsistent.

Seems ok for power tubes in terms of catching bad/worn valves. But the matching is silly. The difference between each LED on the matching is quite large. I have a quad of tubes that test matched on the Orange but in reality, the spread is about 10mA apart in an amp. And no, it's not the amp.

There is some value to this thing, but it's far from reliable. If there was more resolution between LEDs, maybe that would help. But considering the price, I think the Maximatcher is a better value and probably more reliable and accurate.
 
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Microphonic Test with the Mk2: If you tap the tube, and the LED lights all the way, the tube is microphonic.
Otherwise, it's just reading the natural noise in a particular tube (you're not looking for a number)

I've found a number of microphonic tubes like this (I also did the old fashioned tube tap test)
and I felt that the Mk2 did a great job of finding microphonic tubes,
once I re-read the manual, and fully understood how the Mk2's test works.
It works it's own way, not necessarily how I thought it should work.
 
baron55 said:
I believe the reason for the KT77 fail. Is current production KT77 (JJ specifically) don't meet NOS KT77 specs (I have heard this over the years from tube gurus). All my known JJ made good, KT77 failed on the test due to low emissions. But the tubes are good and work in amps with no issues. IO wonder how the Russian KT77 would test.

Also, all my Electro Harmonics 6CA7 all fail as well. The issue is in Europe, a 6CA7 is a EL34. The 6CA7 we think of is actually a US tube that is closer to a 6L6 than a pentode, and has different specs.
Click to expand...
Sorry for this bump but do you know how to test the Electro Harmonix 6ca7’s? Test them as 6L6? since they all fail on the EL34/6ca7 seeing as well on my valve tester.
 
Michiel Kemper said:
Sorry for this bump but do you know how to test the Electro Harmonix 6ca7’s? Test them as 6L6? since they all fail on the EL34/6ca7 seeing as well on my valve tester.
Click to expand...


Most of the current production KT77 and 6CA7 variants don't meet original emissions specs or gain, they work ok, but fail on testers because they are below the old NOS spec.
 
baron55 said:
Most of the current production KT77 and 6CA7 variants don't meet original emissions specs or gain, they work ok, but fail on testers because they are below the old NOS spec.
Click to expand...
Thanks for your answer! I have a quad of the EHX 6ca7 but they physically rattle but might be still good. I’ma bit afraid I blow singing while I use/test/bias them as they sounded great in a Mesa dual rec
 
It is a decent unit for what it does. I use mine at work all of the time and it has helped me diagnose a bunch of tube issues for many customers since I got it. Hasn't steered me wrong as of yet. My customer last week had one power tube that was showing as worn. The other was fine. He said his amp didn't sound great when he was turning it up louder. He didn't want to spend a lot so I found another EL-34 that was close to the one he had and was almost a match. I biased the amp, tested and the amp works and sounds great now.

One of my colleagues has a really nice sounding combo amp....I forget the model (I think it is a Tone King combo) and he had some cracking and noises when playing. I checked all of the tubes except one and they were fine and then I installed the rectifier module on my unit and tested that remaining tube and sure enough, it was very, very low on the worn indicator. Put a new rect tube in and problem solved again.

I could go one with many, many others.

The unit does what it does. For some it may not be what they want or be as specific to their needs, but I don't need the unit to cook me dinner and take me out to a movie. I've got that covered with a great wife! I need it to tell me if the tube is worn, bad or failing and it does a great job for what I need it for.
 
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