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The standard QRS Test Roll is designed to help the user determine Seven basic operating characteristics of any regular 88-note player piano mechanism. They are: General Leakage, Tracking, Tempo Control, Scale Uniformity, Repetition, Capacity and Auto-Sustain. For reasons which will be explained later*, the QRS Test Roll only tests 82 of the 88 notes. The Test Roll also has perforations at the end of the roll to test the function of an Automatic Rewind device if one is present. It should also be noted that the tests on the roll are not individually marked or named. Therefore, small graphics are included below as necessary to help you determine which portion of the roll performs which test. Remember: The player mechanism cannot play the piano any better than the piano plays by hand. Before You Begin: Use a Trackerbar Pump and 'Pump the Bar'.
(DO NOT SKIP OVER THIS PART)
1) Place the Play/Reroll Lever in the Reroll position. This action disengages
the Take-Up Spool from the Transmission, allowing the Take-Up Spool to turn
freely.
Performing this test is quite easy. Simply start pushing alternately on the foot
treadles at a rate of approximately one push per second. In a perfect world, you
should only be able to push on the treadles three or four times (full pumps) before
they resist being pushed any further. NOTE: One of the most important tests of any player piano mechanism is determining how well it can hold vacuum. The degree to which the system holds vacuum is directly related to the overall efficiency and function of the player mechanism. If the player mechanism is incapable of holding vacuum for at least a few seconds, one or more of the components in the system is leaking and should be fixed. To help you locate which component/s in the system is leaking, go to the "Test Your Player" web page - click here! After completing the leakage test, Rewind the roll to the beginning and put the unit back in the Play mode. Then set the Tempo to '70'.
NOTE*: The first series of perforations on the Test Roll are designed to test the operation of 82 of the 88 notes. The Very First Note on the test roll is MIDDLE 'C'. (If Middle "C" is not the first note that plays when the first perforation passes over the trackerbar, there is a relatively serious alignment or tracking problem. There are no perforations on the Test Roll for the first and last three notes. This is because many player manufacturers used those holes for other operations such as Auto Rewind, Auto Shut-Off and/or Auto Repeat. Note: The Tracking Sensors are like the 'Eyes' of the player mechanism. What they 'look at' are the edges of the music roll. Their only function is to provide the automatic tracking mechanism with information about the physical location of the music roll as it relates to the note holes in the trackerbar. If it is operating correctly, the automatic tracking mechanism will keep the holes in the music roll perfectly aligned with the holes in the trackerbar. (Some of the oldest player pianos did not have automatic tracking devices. If you have such a unit, manually adjust the position of the trackerbar so that the note Middle 'C' is the first note to play and that the perforation in the music roll opens the hole in the trackerbar 100%.)
1) Start pumping. NOTE: If the Tracking Device does not perform well, or if it is sluggish in any way, the result will be a poor musical performance at the very least. Poor Tracking can also cause the player mechanism to malfunction.
NOTE: Basically speaking, the first set of perforations on the Test Roll are designed to test the function of each note. Each note should sound five times in a "Da-Dit-Dit-Dit-Dit" manner. List all of the notes that do not perform properly. ![]()
1) Rewind the roll to the beginning. Set the Tempo to '70'. Put the unit in
'Play'.
NOTE: Although this test is primarily used to properly adjust the Air Motor Governor, it can tell you quite a bit about the entire drive line between the 'governor' and the 'take-up spool'. For now, I will only explain how to perform the test.
1) Leave the Tempo set to '70'.
![]() NOTE: As the name implies, this test checks the repetitive ability of both the player mechanism and the piano action. In most cases, it the mechanism fails this test, there are problems with the valves or the regulation of the player mechanism. However, it is also possible that the problem is related to the regulation of the piano action. If you are in doubt about the regulation of the piano action, consult with any regular piano tuner. After performing a few very simple tests, they can tell you if the piano action is properly regulated. 1) Leave the Tempo set at '70' and pump the treadles so that the volume of each note is as soft as possible. Pumping the treadles hard or fast can mask repetition problems. As each perforation passes over the trackerbar, the corresponding notes should articulate evenly. Note all inconsistencies.
![]() NOTE: As the name implies, this test checks the uniformity of the scale from Note 4 to Note 84. What this means is that the volume of each note should be the same as every other note. The volume should be 'uniform' from one end of the scale to the other. Most 'uniformity' problems are related to improper regulation of player action or the piano action. 1) Leave the Tempo set at '70' and pump the treadles so that the volume of each note is as soft as possible. Pumping the treadles hard or fast can play the notes so loudly that it will be difficult to determine which notes are louder or softer than the rest. Note all inconsistencies.
![]() NOTE: This test is designed to give you a good idea about how the unit will perform under normal-to-heavy usage. Unlike the previous portions of the Test Roll, this section plays numerous notes at the same time.
1) Leave the Tempo at '70' and pump the treadles normally (as though you
are playing a regular music roll). |
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The above tests cover the major aspects of a player system that can be checked and/or tested by using the QRS Test Roll. I often use the roll to troubleshoot normal problems like intermittent or leaky valves, and odd problems like incorrect tubing of the trackerbar or leaky exhauster flaps. In the hands of a qualified technician, or an experienced user, the Test Roll can even be effectively used to check the regulation of the player and piano actions. The point is, THE TEST ROLL IS A VERY IMPORTANT TOOL. Recently, the question was asked: "How many repetitions per key does the QRS Test Roll have for each note and what is their spacing? I assume that it will work on the Ampico piano." My Reply: Interesting question! As for the repetitions, there are 5 per inch. One "da" and four "dits" in the first portion of the roll, starting at note 3 and ending at note 85. In the second portion of the roll, there are eight "dits" per 1-3/8" starting at note 85 and ending at note 3. The spacing between the "dits" is 1/8". In every case, the "dits" measure 5/64" in length. A "da" measures 13/64" in length. All of the perforations are rectangular. Their width is 1/16". In the repetition portion of the Ampico test roll, there are five "dits" and one "da" per 1-3/16". However, the "dits" are circles that have a diameter of 9/128" (0.070"). The spacing between the "dits" is 9/64". Based on the above information, simple math dictates that the QRS Test Roll is more challenging with regards to repetition because the "dits" are spaced closer together. This finding is augmented by the fact that the tempo is suppose to be set at 70 during the repetition portion of the test. However, the square area of the rectangle is 0.0048 square inches, and the circle is 0.00385 square inches. In summation, it is my opinion that the QRS Test Roll can be used very effectively to test the repetitive ability of the Ampico, Duo-Art, Welte, and Record mechanisms. And, if a more challenging test is required, the tempo can be raised to 80.......
Musically,
John A. Tuttle |
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