ASeattle
New Member
I have a strange situation with my Denon DP-47F. A few days ago, the sound got dodgy, like there was dust on the stylus. One channel went off intermittently. The stylus of the Ortofon 2m Red was clean. Eventually both channels played fine. But yesterday I replaced the cartridge with an Empire 8000 III with new shibata stylus, thinking the Ortofon stylus might be close shot - it has gotten regular play since 2015. The sound output is now markedly lower on both channels, regardless of cartridge. Where I used to get decent listening level with the volume knob at 8 or 9 o'clock, now I have to go 10 or 11 o'clock. The sound also is a little constricted. Not really bad, just not as open and full as before. The diminished output sound as if there is not enough signal reaching the preamp for it to really boost it. There is no hum. Also no noise until volume is up past 2 o'clock, then a quiet "put-put-put-put" thumping sound that has been there forever, and is why I don't like turning up very high. Plus, turning it up to 11 o'clock is plenty loud. Or used to be.
What's especially puzzling is this in both channels.
The turntable is from the original owner and has not been serviced. All mechanical functions are good and speed is rock steady. The Empire cartridge also came from the original owner and the new stylus is from TurntableNeedles.com. It worked fine previously but has been stored for a couple of years. The preamp is a recapped APT Holman. The power amp is a rebuilt Hafler DH-200 - new boards, filter caps, input jacks, the works. The system plays at the normal, louder level from aux in and tuner inputs.
Troubleshooting so far that has not restored original TT output level:
-Changed back to the Ortofon Red - output still low
-Changed to the Empire - output still low
-Connected TT to Phono 2 input on the preamp and switched left and right inputs - output still low
-Crimped the four connector wires in Denon headshell, both at cartridge end and headshell end.
-Insulated outsides of connectors with liquid tape. They are very close together so thought may be shorting.
-Cleaned connectors and headshell contacts with Deoxit.
-Cleaned RCA plugs, ground and inputs on the preamp with Deoxit.
-Tried a different preamp - a NAD 302.
-Adjusted preamp input impedance and capacitance settings. (But sound decreased without those changing.)
-Wiggled RCA wire from turntable to preamp while playing record to see if cord had deteriorated.
-Rebalanced tonearm for each cartridge and set tracking force using Riverstone Audio digital TT scale.
-Carefully adjusted stylus positions for both cartridges using a Baerwald protractor.
I am thinking of testing the resistance of the TT outputs with my multimeter, as described here, but some people warn against this. https://audiokarma.org/forums/index.php?threads/measuring-turntable-output-with-multimeter.407680/
Any thoughts on what the problem could be and what to test next? Could the wires in the tonearm be crimped or have come loose? Are there any electronics in the signal path that could have failed? Could a capacitor have gone bad?
Grateful for any thoughts!
What's especially puzzling is this in both channels.
The turntable is from the original owner and has not been serviced. All mechanical functions are good and speed is rock steady. The Empire cartridge also came from the original owner and the new stylus is from TurntableNeedles.com. It worked fine previously but has been stored for a couple of years. The preamp is a recapped APT Holman. The power amp is a rebuilt Hafler DH-200 - new boards, filter caps, input jacks, the works. The system plays at the normal, louder level from aux in and tuner inputs.
Troubleshooting so far that has not restored original TT output level:
-Changed back to the Ortofon Red - output still low
-Changed to the Empire - output still low
-Connected TT to Phono 2 input on the preamp and switched left and right inputs - output still low
-Crimped the four connector wires in Denon headshell, both at cartridge end and headshell end.
-Insulated outsides of connectors with liquid tape. They are very close together so thought may be shorting.
-Cleaned connectors and headshell contacts with Deoxit.
-Cleaned RCA plugs, ground and inputs on the preamp with Deoxit.
-Tried a different preamp - a NAD 302.
-Adjusted preamp input impedance and capacitance settings. (But sound decreased without those changing.)
-Wiggled RCA wire from turntable to preamp while playing record to see if cord had deteriorated.
-Rebalanced tonearm for each cartridge and set tracking force using Riverstone Audio digital TT scale.
-Carefully adjusted stylus positions for both cartridges using a Baerwald protractor.
I am thinking of testing the resistance of the TT outputs with my multimeter, as described here, but some people warn against this. https://audiokarma.org/forums/index.php?threads/measuring-turntable-output-with-multimeter.407680/
Any thoughts on what the problem could be and what to test next? Could the wires in the tonearm be crimped or have come loose? Are there any electronics in the signal path that could have failed? Could a capacitor have gone bad?
Grateful for any thoughts!
