Congrats! Glad to hear things worked out!
Newbee help- Volume low even at full preamp volume-???
Guys- my first turntable- Dr. Feickert Firebird- arm- TTW jelco- cart Charisma MC-2: Specs-
:Cartridge Weight: 12 gCartridge Body: aluminiumCantilever: sapphireStylus: super fine line contact nude diamondVertical Tracking Angle: 20 degreesCoil: pure iron crossed-coil with single crystal high purity copperOutput Voltage: 0.42 mV at 3.54 cm/sec. Internal Impedance: 14ohmsFrequency Response: 20 –25,000 Hz ± 1 dBChannel Balance: better than 0.5 dBChannel Separation: better than30 dBDynamic Compliance: 10 um/mNRecommended Loading: 100 –1,000 ohmsRecommended Tracking Force: 2.0 g ± 0.1 gTracking Ability at 315 Hz / 2 g: 80 uMRecommended Tonearm Mass: medium
Phono preamp- Rogers PA-1A
Preamp- Wyetech ruby-
Ok- I set the Rogers Phono Pre per Charisma rec.-"We would suggest you to try the 100 Ohm and 10K Ohm of the resistive selection. Capacitance is sensitive to moving magnet cartridges, but not moving coil."
I get very low volume even with the Wyetech preamp at full volume- Please help a Newbee out- What am I doing wrong??thanks gary
:Cartridge Weight: 12 gCartridge Body: aluminiumCantilever: sapphireStylus: super fine line contact nude diamondVertical Tracking Angle: 20 degreesCoil: pure iron crossed-coil with single crystal high purity copperOutput Voltage: 0.42 mV at 3.54 cm/sec. Internal Impedance: 14ohmsFrequency Response: 20 –25,000 Hz ± 1 dBChannel Balance: better than 0.5 dBChannel Separation: better than30 dBDynamic Compliance: 10 um/mNRecommended Loading: 100 –1,000 ohmsRecommended Tracking Force: 2.0 g ± 0.1 gTracking Ability at 315 Hz / 2 g: 80 uMRecommended Tonearm Mass: medium
Phono preamp- Rogers PA-1A
Preamp- Wyetech ruby-
Ok- I set the Rogers Phono Pre per Charisma rec.-"We would suggest you to try the 100 Ohm and 10K Ohm of the resistive selection. Capacitance is sensitive to moving magnet cartridges, but not moving coil."
I get very low volume even with the Wyetech preamp at full volume- Please help a Newbee out- What am I doing wrong??thanks gary
20 responses Add your response
It sounds like you have narrowed it down to bad tubes, since all connections seem to be correct. Asking for tube recommendations can be tricky, as we don't know your budget or personal tastes. Choosing tubes can be subjective, just like choosing cables. NOS can be pricey, but worth it to some. Some like the warmer sound of Mullards/Brimars, etc., while others like more revealing tubes like Amperex/Siemens, etc. Try to find a reputable dealer like Brent Jesse if buying NOS tubes. Personally, I like Amperex NOS tubes, and if going with current production tubes, I like the Psvane tubes. Obviously, YMMV. Let us know how you make out with some fresh tubes. |
According to the KAB gain calculator, 58 dB is optimum gain for 0.4 mV cartridge. https://www.kabusa.com/pregain.htm Keep in mind that fluffers Wytech Ruby preamp also has 12 dB of gain. So if he has it connected correctly, and all tubes are up to spec, he should have PLENTY of gain with his 65 dB of gain using 12AX7's in his Rogers phono preamp, and the 12 additional dB of gain in his Wytech preamp. |
How much gain does the Rogers phono stage put out? If I understand from above the 12AU7 puts out 50db gain, but switching to the 12AX7 results in 65db gain...correct? If so, 65db should be plenty of gain to drive the .4mv output cartridge. Absolutely no need to consider switching to a moving magnet! You've got a simple wiring error or a bad tube in all likelihood. And for god's sake, never any need to turn the volume all the way up. If you pass 2:00 and it's not plenty loud, usually something is setup incorrectly. Cheers, Spencer |
Hi Gary, first, do you have the interconnects plugged into your MC input on your Rogers PA-1A? If not, then remove them from the MM inputs and put them on the MC inputs. Second, you can do as griiffithds suggest, and use all 12AX7's which should provide 15 dB more gain. If this still doesn't provide enough gain, have the tubes checked out, make sure they are reading okay. |
Your cartridge output is only 0.42 milivolts. If you are using the 12UA7 tube, then perhaps you are not getting enough gain. Switch out the supplied 12UA7 tube with the supplied 12AX7 tube to get an additional 15 dbs of gain. That will allow you to turn down the volumn knob a bit. In the future, if you buy a lower output cartridge, you might be in the same situation with not enough gain so keep this gain to cartridge output number in the back of your head. Regards, |