Orange Amplification are proud to launch a pioneering new technology to match, test and grade valves – the Orange DIVO VT1000 Valve Tester. This ground breaking new product will help every guitarist, rental company, valve amp manufacturer, guitar tech and guitar / hi-fi store across the planet.
The compact and extremely easy to use VT1000 is a fully automatic valve tester, which performs a wide range of tests quickly and accurately. The benefits of using the VT1000 are clear and wide reaching; users can quickly and simply match and test valves, plus receive a reliable health check as to whether their valves are good, bad or worn.
Orange Amps developed the world’s first fully automatic, portable, digital valve tester, the VT1000, to make it easy to test amp valves. Until now testing valves with little or no knowledge of valve theory was difficult, expensive and often unreliable. This new product will test all popular power and pre-amp valves. Its ease of use will appeal to all valve users whether amateur, professional or in the music retail trade.
The unit has one octal and two nine pin valve sockets for different valve types; simply insert the valve to be tested into the correct socket, select the valve type from the list on the unit and press ‘OK’ to test. The results are displayed clearly and concisely using LEDs and will test for a wide range of fault conditions, which could easily cause damage to other components. The simplicity of operation belies what is going on ‘inside the box’, where a CPU controlled testing system is in operation, allowing full control over all inter-electrode switching and measurement operations.
In approximately two minutes, the VT1000 performs an extensive series of tests including:
Heater filament test: Short circuit
Heater filament test: Open circuit
Heater filament test: Tolerance check
Heater cathode insulation: Leakage
Heater cathode insulation: Short Circuit
Tests for heater current abnormalities
Screen grid test
Mutual conductance test
Dual test for double triodes
Inter electrode leakage
Inter electrode short circuit
Flash-over (arc detection, high voltage breakdown)
Gas ionisation test
The VT1000 really opens the door to everyone to have an extremely simple, portable, reliable, inexpensive and safe way to test valves.
The VT1000 incorporates patent-pending technology and currently tests the following valves:
EL34/6CA7; EL34L; 6L6; 6V6/6v6GTA; KT66; KT77; KT88; 6550; 5881; EL84/6BQ5; ECC81/12AT7; ECC82/12AU7; ECC83/12AX7; ECC99; 12BH7
“Other companies will be looking with envy at Orange’s ground-breaking technology.” | 4 Stars | Guitar Interactive Magazine Issue 76
“The first and possibly only valve tester that anyone can use without any specialist knowledge.” | 4 Stars | Music Radar
“If your interest in valve amplifiers goes beyond merely playing through them, it’s a wonderful tool to have” | 91/100 | Guitar & Bass Magazine
“I think there will also be a large group of people who will think the VT1000 is one of the best things since sliced bread.” | Sonic State.com
Will any damage occur if a faulty valve is plugged in?
No, the VT1000 is fully protected against damage resulting from valve faults.
[expand title="Can I remove the valve immediately after the test completes?"]Once the test completes and the green, yellow or red indicator lights, then the test is complete; however, as valves may get hot during the test, we recommend that you make sure that the glass envelope is cool before attempting to remove it. In any case, we recommend the use of protective gloves when handling valves.
If I re-test the same valve the readings are slightly different, is this OK?
Yes, the VT1000 uses a complex algorithm which analyses the many different tests which are automatically performed. In order to keep the total test time to a minimum, the unit is calibrated at manufacture to test cold valves. If a valve is subsequently re-tested while still warm, then a slightly different reading may be observed. There is nothing to be gained by re-testing the valve as the glass envelope will become hotter and increase the length of time before it can be safely removed.
The DC supply to the tester is only 19V; how can this test the valve properly?
The VT1000 internally generates all the voltages necessary to test the valve. These are automatically controlled and applied to the various electrodes within the valve under the control of a microcontroller, according to the type of valve selected.
Most valve testers do not use the voltages that are found in real amplifiers, is this one any different?”]Yes, parts of the test procedure analyses the performance of the valve at voltages approaching those found in amplifiers to test for internal arcing and ‘flash-over’.
Can physically damaged valves be tested?
Although no damage will occur to the VT1000 by testing faulty or damaged valves, under no circumstances should any attempt be made to insert into the test socket or to test a valve which is physically damaged as this could present a hazard to the user or others. If a valve envelope is accidentally damaged during a test, the ‘OK’ button should be used to terminate the test and the power connector removed. The valve should then be allowed to cool after which it should be removed using protective gloves and then safely disposed of. DO NOT touch any exposed metal parts of the valve during the operation and ensure that no fragments of glass remain around the tester before using it again.
Can I use the VT1000 in different countries or do I have to order a special model?
The VT1000 is supplied with a ‘universal’ power supply which can operate anywhere in the world without any user adjustment. Mains leads are available with UK, USA and European plugs. Alternatively, you may already own a universal travel adaptor.
Some faulty valves fail at different stages in the test, is this normal?
Yes, the VT1000 automatically performs many tests on the valve whilst the LED bar-graph elapsed time indicator is running. If the valve fails at any point, the test is automatically terminated and the red ‘FAIL’ LED illuminated. In this way, the test time for faulty valves is kept to an absolute minimum.
If I accidentally plug a double triode into the EL84 socket or vice versa, will any damage be caused either to the valve or to the VT1000?
No, the microcontroller will detect that the wrong type of valve is fitted and the red ‘FAIL’ LED will be lit. Unlike some competitive products, no damage will be done to the valves under these circumstances.
I have noticed that on some valves the silver appearance on the glass has turned a milky white colour and is sometimes flaking. Does this signify a faulty valve and will there be any problem in testing it?”]The ‘silver’ coating usually seen on the glass of most valves is produced at manufacture and is known as the ‘getter’. Its purpose is to ‘mop up’ any remaining air or gas molecules in the valve after the air has been pumped out to form a vacuum. If the coating appears milky white, or sometimes almost transparent, this indicates the presence of air in the valve which will render it useless. There is little point in further testing valves in this condition and they should be disposed of in a proper way. Careful handling is advised because the presence of air may indicate a broken or cracked glass envelope.
What tests does the VT1000 perform?
In addition to the ‘standard’ range of tests, which include internal short circuits and open circuit heater, the VT1000 also performs inter electrode leakage measurements and tests for correct anode, cathode, screen (for Pentodes & Beam Tetrodes) and heater current values for each type of valve selected. Valves are extremely complex devices and attempts to categorize them using just one or two measured parameters are often unsuccessful in ‘real’ applications, such as audio amplifiers. The measurements made by the VT1000 throughout the entire test procedure are finally processed using a sophisticated software algorithm in order to report any existing problems and, in some cases, preempt future fault conditions. In a similar way, the ‘matching number’ indicated by the LED(s) at the end of the test, is based on a combination of measured parameters to give an indication of how the valve will perform, according to its typical function in an amplifier.
If I accidentally select the wrong valve type and start the test, will any damage be caused?
No, in the majority of cases, the valve will just test as either ‘out of spec’ or as a fail if the wrong type is selected.
Sometimes new valves don’t give high matching numbers; does this mean that they are still OK?
Normally, yes – In general, a higher number indicates a newer or less worn valve, however due to manufacturing tolerances, a range of values are possible, even with new stock. Manufacturers of amplifiers design their products to accommodate these normal tolerances without any deterioration in performance. When fitting power valves in pairs or quartets, the closeness of the number is much more important, as mismatched valves will directly impact the sonic performance of the amplifier. Pre-amp valves are often ‘double triodes’ i.e., they have two identical valves in the same glass envelope and close matching of these two ‘halves’ is very important in some parts of the circuit.
Why do I need a valve tester when I can test old or suspect valves in an amplifier?
There are several reasons why old or suspect valves should not be ‘tested’ directly in an amplifier. Valves can have many different fault conditions; some are obvious, such as internal arcing or inter-electrode short circuits. These fault conditions may cause serious damage to other components in the amplifier. Others are not immediately obvious but can lead to instability, unreliable operation, poor performance and possibly long term damage to other components. The VT1000 gives a clear indication of a wide range of fault conditions which could otherwise cause damage to other components. In addition, a patented ‘predictive’ software algorithm has been developed from the analysis of hundreds of faulty valves, which seeks to intelligently determine the onset of fault conditions, sometimes before they become apparent in normal operation.
How does the Orange VT1000 differ from other commercially available valve testers?
Commercial valve testers have been available, almost since valves were invented, incorporating many excellent techniques and designs over the years. However, the vast majority have a number of common features, which we considered to be a barrier to the modern valve user namely:
• They require a certain level of user interaction in that parameters have to be set for individual valves being tested;
• They require a certain depth of knowledge about valve theory, which some users may not have;
• The results obtained on meters or digital readouts require a certain level of user interpretation;
• They are often quite large and bulky
In a lot of cases, they are also not very portable and since most are mains operated, require selection of mains voltage if required to be used in other than their native country.
When developing the VT1000 we decided to ‘break the mould’ to produce a fully automatic valve tester, which performs a wide range of tests quickly and accurately. Requiring little or no knowledge of valve theory, it can be operated by experienced users and those who just want to know that the valves in their amplifier are in good condition. It requires no user interaction other than inserting the valve to be tested into the correct socket, selecting the type from a list using two up/down buttons using an LED bar display, then finally pressing a ‘START’ test button.
The test then proceeds without any further user input and an elapsed time is displayed on the bar-graph display during the test, when one of three LED’s is lit to indicate a ‘PASS’, ‘WORN’ or ‘FAIL’ condition.
In addition, the LED bar-graph display indicates a ‘matching number’ which is based on a summation of the many results obtained during the test and has been specifically designed to reflect the operation of the valve, according to its normal function in an audio amplifier. For example, power valves are graded with their emission and control grid performance as primary factors, whereas pre-amp valves are graded with different parameters to reflect their role in signal amplification and phase splitting applications. If the valve is faulty or worn, then this will be indicated at the end of the test.
The simplicity of operation belies what is going on ‘inside the box’, where a sophisticated microprocessor controlled testing system is in operation, allowing full control over all inter-electrode switching and measurement operations. In addition all voltages required by the tester are internally derived, stabilized and controlled by the microcontroller, allowing us to perform static and transient tests rapidly and without generating unnecessary heat. The test algorithms used have been developed using data from tests on hundreds of new, used and faulty valves.
We are passionate about valve technology and our aim throughout has been to make the Orange VT1000 a sophisticated, modern, truly portable valve tester which is primarily useful but also stylish. We believe that it will appeal to all valve users whether amateur, professional or in the music retail trade.
How does the rating system relate to Gain in preamp and power amp valves. Higher rating = lower gain?
Higher ratings in output tubes will have more output power and later onset of distortion. This is also the case with pre-amp tubes but because they will be driving the subsequent stages harder, this can sometimes result in more apparent gain and overdrive.
Matching power amp tubes: Of course, same rating tubes of the same brand can be used as a matched pair, but what if the rating is 1 or 2 points off. Is the use in the same amp safe? What’s the max safe discrepancy? What if the matching is identical, but the brand is different?
Always match with the same make of output tube, as other characteristics will be different with different brands even though the same match number is displayed. If more than 1 or 2 points of difference is displayed between two output tubes, they are not well matched so the amp should be biased to the tubes with the higher rating in order to not draw too much current if this particular set of tubes is to be used.
At what voltage does the VT1000 test for flashover?
Flashover test voltage for all valve types 380V DC although the current is limited to prevent large “firework” displays.