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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



fluffers

Showing 5 responses by jmcgrogan2

jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
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.
jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
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.
jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
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.
jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
Bad news: Sorry, I have no experience with the 6GH8 tube.


Good news: However, a quick web search shows that they appear to be inexpensive to replace. Lots cheaper than the 12AU7 or 12AX7!
jmcgrogan2's avatar
jmcgrogan2
6,346 posts
 
Congrats! Glad to hear things worked out!
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