The "plosive" sound on high notes could easily be a flaw or limitation in the receiver, as suggested above, but it's about equally likely to be due to stylus mistracking. If that's the case and it's your stylus that's mistracking, you may be damaging your records.
Clean the stylus and play a suspect passage. If the "plosives" go away, you've found the culprit. Keep the stylus clean. Search for "magic eraser" on this and other vinyl forums for a cheap and effective method.
If the "plosives" remain after stylus cleaning, increase tracking force slightly (by .1 or .2g) and play the suspect passages again. If the "plosive" go away or are reduced, you've found the culprit. Fiddle tracking force until they go away altogether.
Mistracking is a major cause of vinyl damage and it's usually caused by playing with tracking force set too low, which can let the stylus lose contact at higher velocities or amplitudes. If the stylus breaks loose even a little bit, well, the results of a diamond chisel rattling around inside a plastic groove are easy to imagine. That kind of damage can never be repaired, so prevent it for the health of your vinyl.
Note: if these are old records, plays on previous rigs could have damaged them in exactly this way. On replays, the resulting damage sounds virtually identical to actual mistracking. There's an easy way to check, but the above steps should be be done first. It's critical to make sure your rig isn't mistracking.
Clean the stylus and play a suspect passage. If the "plosives" go away, you've found the culprit. Keep the stylus clean. Search for "magic eraser" on this and other vinyl forums for a cheap and effective method.
If the "plosives" remain after stylus cleaning, increase tracking force slightly (by .1 or .2g) and play the suspect passages again. If the "plosive" go away or are reduced, you've found the culprit. Fiddle tracking force until they go away altogether.
Mistracking is a major cause of vinyl damage and it's usually caused by playing with tracking force set too low, which can let the stylus lose contact at higher velocities or amplitudes. If the stylus breaks loose even a little bit, well, the results of a diamond chisel rattling around inside a plastic groove are easy to imagine. That kind of damage can never be repaired, so prevent it for the health of your vinyl.
Note: if these are old records, plays on previous rigs could have damaged them in exactly this way. On replays, the resulting damage sounds virtually identical to actual mistracking. There's an easy way to check, but the above steps should be be done first. It's critical to make sure your rig isn't mistracking.