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Preamp - 18 dB Gain too low?

Being a newbie to audio stuff, I'd like to hear your opinion whether should I replace my preamp. To get to a reasonable loud volume, my preamp has to be at around 1PM to 2PM position for most of CD and music DVD. Should I get another preamp with higher gain? If so how much more? Why don't the manufacturers make higher gain? Probably some sonic compromise with high gain active preamp?

Any suggestions are welcomed.

Preamp: Conrad Johnson PV-10AL, gain 18 dB.
Amp: Shuguang S845MK (tube amp 848)
Speakers: Tekton Lore (Sensitivity 98 dB)
Room: 25 x 17 x 8'
nguyen787
nguyen787 OP
52 posts
 
Hi Dave,
Thank for sharing the detail of your measurement. I swapped the active preamp CJ 18 dB gain with a passive Lightspeed Attenuator, and I found that most of CDs, I have to push the volume knob to 3 - 5 PM (MAX == 5 PM) to obtain the desirable volume. The low sensitivity amp, 4 V, seems to be an issue. Bought this amp without understanding the input sensitivity spec...

What is attenuation voltage ratio and what does it tell us?
phd
1,008 posts
 
Some amps have high input gain because they are designed to be used with passive preamps which have no gain at all. I can tell you that CJ amps need a preamp with relatively high gain to properly drive them. 18db of gain is higher than average.

I have owned some CJ preamps and they do invert phase. I corrected the phase by reversing the wiring to the speaker binding posts. I couldn't tell any difference myself. It could be because some recordings are already recorded with inverted phase.
intactaudio
84 posts
 
Hey,

'between 3-5pm' are just arbitrary numbers and without seeing an actual attenuation plot vs. knob rotation of the LDR, you really don't know that much. Also seeing an input and output impedance plot of the device WRT attenuation would be needed to see if any red flags go up.

dave
georgehifi's avatar
georgehifi
4,966 posts
 
Nguyen hi, just looking at the factory specs for your 845 amps they are very sensitive at There is something not right with your system as Red Book standard for cdp is 2v out and most are higher than this so your Lightspeed should be below half way. What is your cd or source (has it been modded?) please give model no's

Cheers George
georgehifi's avatar
georgehifi
4,966 posts
 
Sorry a line was left out above
Nguyen hi, just looking at the factory specs for your 845 amps they are very sensitive at
Cheers George
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