RECORD CHANGER FAQ

Frequently asked questions about record changers

People have asked me various questions about record changers. Here are the answers:

1. Q: Don't record changers harm records?

   A: The earliest ones did:

   • Don't use the kinds that slide records around or use knife blades to separate them.

     Note: The Thorens TD-224 and the later Lincoln changers (if kept in good repair) are not dangerous even though they move records around.

   • Beware of anything with a tonearm that moves stiffly.
   • Don't change World War II era records (1939-1946). They get brittle with age.
   • Don't use 78 rpm records with a straight (umbrella) spindle.

2. Q: I thought that the grooves rubbing together damaged records. Does this happen?

   A: There are several parts to this answer:

   • If the record is warped, the grooves will rub.
   • A flat 33 or 45 rpm record is designed with the label thicker than the grooved surfaces. The grooves will not rub if the record is flat.
   • 78 rpm records will rub the grooves together.
   • Unless the records are dirty, the rubbing of the top surfaces of the grooves will not cause any damage.
   • Some changers are designed to stop the turntable during the change cycle, so the groove will not rub.

3. Q: What about dropping records from the spindle? Does that cause damage?

   A: It is not a good idea to drop certain records from the spindle:

   • Records made between the years 1939 and 1946 should not be dropped without the sloped spindle of a push type changer. These records are made of substandard materials that break easily, due to the rationing that was in effect during those years.
   • Changers with the straight "umbrella" type spindle can damage most 78s. Shellac records should not be dropped from these, because the center holes are often weak.
   • The one umbrella spindle I would trust to drop a shellac record was on the Garrard Lab-80, which lacks the 78 rpm speed.
   • Other records will not be harmed by dropping. A well-designed modern record changer will drop the record perfectly flat, so a cushion of air slows its fall.

4. Q: How does a record changer separate the records? Does it grip the other records with something? And doesn't that hurt the records?

   A: Two main ways to separate records are found on modern drop changers:

   • Push type changers have either a balancing arm (overarm) or a side shelf. They do not "grip" the records in any way. Instead, this kind has a ledge on one side of the spindle. The records sit on this ledge. The changer then pushes the bottom record sideways until it falls off the ledge. A record guide in the spindle keeps the other records from moving sideways, so they stay up on the ledge. Then the record dropping parts return to their previous positions.
   • Changers with the straight "umbrella" type spindle do grip the records. After the records are gripped, the three fingers holding up the bottom record retract to drop the bottom record. Then the record dropping parts return to their previous positions.

     Usually the grippers are spring loaded, so the records are not subjected to undue stress. But shellac records should not be dropped from these, because their center holes are often weak.

   Two other ways were used by certain manufacturers:

   • Garrard made a spindle that combined both methods on the Lab-80. A wedge moved all of the records except the bottom record to one side. This made them move onto a sloped ledge. But the wedge does not hold the records up. It just keeps them level. The ledge holds them up, so the wedge does not need to apply much force. Once the wedge has moved the records onto the ledge, the fingers release the bottom record. Then the parts return to their previous positions. Shellac records could be used with this, except that the 78 speed is not provided.
   • Philips made changers that pushed all of the records except the bottom record to one side and then removed a finger from under the bottom record to drop it. Then the record dropping parts returned to their previous positions. This is essentially a push type spindle.

   Large-hole records are handled by different methods:

   • Most changers use a large spindle that slips over the standard spindle or replaces it.
   • Many changers expect the user to buy spiders (plastic inserts) that reduce the size of the center hole of the record to the small-hole size. A spider is needed for each record.

   Large-hole record spindles also use different methods to drop the records:

   • Many changers use large duplicates of the mechanisms in the small spindles to drop large-hole records. The parts in the large spindle move in the same way the parts in the small-hole spindle move.
   • Some changers have a cheap large spindle with an offset in it that uses the record pusher in the small spindle to drop the records.
   • The original RCA 45 changers have a large spindle with two moving shelves and two slicer blades. The large-hole record is designed to be thicker in the label area than it is near the center hole, leaving spaces for the slicer blades to fit between the records.

     The records normally sit on the shelves. To drop a record the slicer blades come out between the records. Then the shelves retract, dropping the bottom record. Then the parts return to their previous positions.

     Many of the large spindle attachments use this same shelf and slicer mechanism.

     Most large spindles for umbrella spindle changers use the shelf and slicer mechanism.

   Very early changers used large knives to separate records by slicing between them at the rims. These break records, and should never be used.

5. Q: Doesn't the trip mechanism exert an objectionable force on the arm?

   A: Older changers did, but newer changers do not:

   • The old changers with the trip that detected the backward motion of the arm (from the eccentric finishing groove) placed an undesirable force on the arm.
   • Any force exerted by a modern velocity trip is so light that the stylus does not notice it. Some changers use a beam of light to trip the change cycle.

     An exception was a series of Garrard changers that used a lubricant in the velocity trip that turned rubbery when it dried out. This was easily repaired (graphite is a better lubricant), but it did produce the excessive force while the fault remained.

6. Q: How does the record changer know when the record is over?

   A: The velocity trip used on most modern changers detects the increase in the speed of the arm when the stylus enters the runout groove.

   Other methods have been used:

   • Early changers and cheap changers used the position trip. The changer tripped when the arm reached a certain position on the record. This was unreliable, because manufacturers did not agree on where a record should end.
   • Changers in the 1930s and 1940s used the eccentric (or oscillating) trip. This required an eccentric finishing groove on the record, and tripped when the arm moved away from the spindle.
   • Luxor used the progress trip. It tripped when the arm stopped moving closer to the spindle. It also tripped if the stylus repeated the same groove.

7. Q: Why does my record changer sometimes put the arm in the wrong place?

   A: This is usually a result of using it wrong. Here are some examples:

   • Changers that can take record sizes intermixed in the stack usually can not correctly play a single record that is already on the turntable. The record must be dropped from the spindle for the size feeler to know the correct size.

     Note: Some intermix changers have single-play size controls.

   • Some record changers were made to play only certain size and speed combinations. These were made in the late 1940s and after 1966. Other kinds of records must be played manually. Cheap!
   • Some record changers require that the smaller records must be placed after (above) the larger records.
   • Some records are made with a nonstandard diameter. They must be played manually on changers that can't change odd sizes.
   • Some record changers can take 10" and 12" records intermixed, but must play 7" records in a separate stack.
   • A few record changers use the size of the hole in the record (or which spindle is in use) to set the size and/or the speed.

8. Q: How does the record changer know where to put the arm?

   A: RECORD CHANGER SIZE SENSING is a page that explains it all.

9. Q: How does the record changer know when the stack of records is over?

   A: Several methods are used:

   • If the record changer feels the size by feeling the unplayed stack or a separated record, the absence of a record triggers shutoff.
   • If the changer has an overarm or record clamp, the dropping of this below where records are stacked triggers shutoff on the next (not the current) change cycle.
   • Some changers look for the weight of a record on the spindle itself. When no weight is present on the spindle, it triggers shutoff on the next (not the current) change cycle.
   • Changers with umbrella spindles look for the weight of a record on the spindle fingers. When no weight is present on the fingers, the spindle does not drop the record and shutoff occurs on the current change cycle.

10. Q: Can it hurt the record changer to touch the arm while it is moving?

    A: It depends on the changer design.

    • Most modern changers have what is called a safety drive to prevent damage. But there are exceptions.
    • If using any of the following record changers, do not grab the arm during the change cycle:
      • Any changer made before 1955 (some do have safety drives, but most do not)
      • Any jukebox
      • Any RCA changer (They never had an effective safety drive)
      • Any small 45 changer (Only V-M and Webcor had safety drives)
      • Any Garrard RC series changer
      • Any Garrard Type A, A-70, and Lab-80 series changer

11. Q: I want to play a record manually, but the spindle is not removable. How can I get the record down to the turntable?

    A: There are two ways:

    • If the record changer is a push type with an overarm or a side shelf, just push the record sideways so it falls off the spindle ledge.
    • Place the record on the spindle in the usual way. Start the changer and let it drop the record. Catch the arm as it lowers to the record (or use the cue control, if available).

12. Q: I don't have the instructions. How can I tell if the used changer I bought takes intermixed record sizes?

    A: Look for the following:

    • If there is some device or control with record sizes marked on it, the changer usually can not take mixed sizes.
    • Record changers with size feelers built into the turntable can not take intermixed sizes. But you don't have to move a control to set the record size.
    • Any changer with a device the record strikes while it falls can intermix all of the standard sizes that strike it with one size that does not. These records can usually be placed in any order.
    • Any kind of device that touches the unplayed stack usually allows what is called an arranged intermix. Larger records must be placed below smaller records.
    • Any changer with a device that feels the record while it is lowered half an inch from the stack can intermix all of the sizes the device can sense. These records can usually be placed in any order.
    • If the changer has both a control for size and a size feeler, the size control is usually for single play use. But some early changers combined a size control for the new 7" records with the ability to intermix 10" and 12" records.
    • Some changers measure the exact size of the record with the pickup arm. These can take odd-sized records intermixed in arranged order, or in a random order if it feels a lowered record.
    • A few changers have rollers under the arm that feel the exact size of a record. These can also take odd-sized records intermixed in any order.

13. Q: Can some changers really take different speeds mixed in the same stack?

    A: Yes. These use the fact that most 33s are 12" or 10", while most 45s are 7". Examples:

    • The Webcor "Magic Mind" series
    • Glaser-Steers GS-77 (and identical units Heathkit AP-3 and Philco M-39)
    • Fisher Lincoln 70
    • The page author modified a Collaro Conquest to do this. But the 45s must be last.
    • Some jukeboxes use the center hole size to set the speed for each record.

14. Q: Why is tracking force measured in grams, when the gram is not a unit of force? The gram is a unit of mass.

    A: Blame the Germans:

    • They have a measure called the pfund (p) that is the force made by a weight of one gram. It is not a metric unit.
    • Translators who don't know the difference between mass and weight translated "pfund" as "gram" in other languages.
    • It unfortunately became a de-facto standard in English-speaking countries, and nobody did anything to stop it.
    • The correct unit of measure is the millinewton (mN). Gravity exerts a force of 9.8 mN on one gram of matter.
    • Another way is to use the "grams equivalent force" (g equiv). This is the same as the pfund.
    • 2 "grams" = 2 g equiv = 2 pfund = 19.6 mN

15. Q: Why does the arm on my changer swing out an inch beyond the rest post during the change cycle?

    A: Changers with slide cams do this:

    • A slide cam slides back and forth once during the change cycle. Shaped surfaces on the sliding cam operate all of the parts.
    • The cam moves the arm farther to be able to move the record dropping parts after the arm is out of the way of the records.
    • This also gives the automatic shutoff parts room to move into or out of the position to block the arm travel.

16. Q: Why does the arm on my changer swing in and out multiple times during a change cycle?

    A: Many changers use the tip of the arm to feel the record size. They do this:

    • The changer first moves the arm out over the rest post.
    • The changer next moves the arm in to touch the rim of the next record to feel the size.
    • The changer moves the arm out to clear the way for the record to drop.
    • The changer moves the arm in to set the stylus on the record.

    A: Miracord and TrioTrack changers use the arm to feel the record size in a different way:

    • The changer first moves the arm in or out to be over the 7" position.
    • The changer next moves the arm up, and then oscillates it alternately in and out to find the rim of the next record on the stack.
    • The Miracord moves the arm out to clear the way for the dropping record. The TrioTrack instead uses the arm to push the record off the spindle ledge, then immediately moves it out of the way of the record.
    • The changer moves the arm in to set the stylus on the record.

    A: Some Dual and Luxor changers use wheels in the tip of the arm to feel the record size:

    • The changer first moves the arm out over the rest post to clear the way for the record to drop.
    • The changer next moves the arm in to set the feeler wheel down on the record.
    • The feeler wheel rolls the arm to the rim of the top record on the turntable.
    • Some of these changers lift the arm, reposition it, retract the wheels, and lower the arm. The others retract the wheels as soon as they run off the edge of the record, setting the stylus on the record.

    Note that some Philco changers momentarily swing the arm in when it first rises. This is an unintended artifact of the method used to raise the arm.

17. Q: Why does my changer have control positions for only a few combinations of size and speed on the knob?

    A: The manufacturer made it as cheaply as possible, by providing for only the most popular record types.

18. Q: Why does my changer turn the speed control to 45 after playing a stack of 33 rpm records?

    A: You have a Webcor Magic Mind changer that intermixes record speeds. If you load larger records, it will change back to 33 during play.

19. Q: Why does my changer fail to trip at the end of some records?

    A: There might be something wrong with it. But the following record defects can cause a normally operating record changer to fail to trip at the end.

    • The record has no leadout groove.
    • The leadout groove does not move very far.
    • The record has an eccentric trip groove that returns to be adjacent to the playing grooves.
    • The center hole in the record is enlarged.

20. Q: Why does my changer sometimes trip before the end of some records?

    A: There might be something wrong with it. But the following record defects can cause a normally operating record changer to trip too soon.

    • The playing grooves run in farther than the trip mechanism can handle.
    • The grooves were pressed off-center, so the arm swings back and forth during play.
    • The center hole is off-center.
    • The center hole in the record is enlarged.

21. Q: Why do some records fail to drop on my changer?

    A: There might be something wrong with it. But the following record defects can cause a normally operating record changer to fail to drop certain records.

    • The record is too thick.
    • The center hole of the record is too small and the record binds on the spindle.

      Note: Some NEW 180-gram-vinyl records are made with center holes that are too small (violating RIAA standards).

    • The record is warped, causing a shelf pusher to miss the edge of the record.
    • The center hole in the record is damaged.
    • When spiders are used in large-hole records, they sometimes jam against each other.

22. Q: Why do some records drop two at a time on my changer?

    A: There might be something wrong with it. But the following record defects can cause a normally operating record changer to drop some records two at a time.

    • Two adjacent records are both too thin.
    • The center hole in one record is enlarged or damaged.

    Another possibility is that the sliding record guide on a push-type spindle is stuck in a too-high position.

23. Q: Why does my changer repeat the last record instead of shutting off?

    A: There can be several different reasons why the changer is repeating the last record:

    • The user did not put the overarm or record clamp on the record stack.
    • One record failed to drop and the one below it repeated.

    Another possibility is that the record changer is one of the cheap ones from the 1950s that repeats the last record. Most of the little 45 changers repeat the last record.

    A very few models of record changers repeat 7" records, but not other sizes. A few others repeat large-hole records, but not small-hole records.

24. Q: My neighbor uses Audiotex Record Repeaters to repeat his records in the stack. Why don't they work on my changer?

    A: The changer must use certain methods to detect records for the repeating discs to work. They will not work with the following kinds of record changers.

    • Record changers where the side shelf pushes the record will jam or break the next record instead of dropping the disc. The shelf can't push the disc.
    • Record changers that feel the size of a separated record will either shut off or play only the last part of the record.
    • Record changers that carry the record (instead of dropping it) will remove the record before placing the repeating disc on the turntable. The pickup could set on an empty turntable.
    • Some umbrella spindles won't detect or drop the discs. The changer will shut off when it comes to a disc.
    • Record changers that feel the size of a falling record will work with 7" records, but not larger sizes.
    • If the size feeler feels the unplayed stack, another record the same size must be placed above the repeating disc.