Clarification above: attenuators would be on integrated's CD input.
Convert cartridge output voltage to db gain
Happy holidays everyone. I hope that you may help me with a problem. I have re-configured my system, preamp and amp gone, I'm now using a integrated amp. I still have my phono stage and cartridge. My cartridge has a 0.24mV output, my phono stage has 66 db of gain. This used to sound fine, but now I notice that the noise floor is too high for me. So I'm debating on whether to look for a higher gain phono stage, or more likely, a higher output cartridge.
So now my question, how much more output would give me how much more gain? Should I be looking at a 0.5, 1.0 or 2.0+ mV output cartridge? I think I need at least 10 db more gain, and there are not many 76db+ phono stages out there. So what do you analog experts think? Is there any table out there that can show me how to convert voltage output to gain increase? TIA.
Cheers,
John
So now my question, how much more output would give me how much more gain? Should I be looking at a 0.5, 1.0 or 2.0+ mV output cartridge? I think I need at least 10 db more gain, and there are not many 76db+ phono stages out there. So what do you analog experts think? Is there any table out there that can show me how to convert voltage output to gain increase? TIA.
Cheers,
John
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- 37 posts total
Jmcgrogan2, there is something I don't understand about your total system gain. The Parsifal Encores are ~89dB efficient, so they aren't impossibly hard to drive. From your AudioAsylum system list(linked to in a power cable review you posted), you have the VAC Avatar SE integrated(25dB ultra-linear/23dB triode) and the Walker Signature phono preamp. If the Signature is like the Reference, it has adjustable gain from 40-66 dB. |
Actually, the specs on the Avatar SE indicate that its preamp section has a gain of 24db, and its power amp section has a gain of 25 dB ultra-linear and 23 dB triode mode. It also indicates "Maximum input signal: Infinite (attenuation precedes line stage)." So with the phono stage set for 66db gain, the 0.24mv cartridge output would result in 480mv into the preamp section, which certainly will not overload it (in addition to the quoted statement, additional evidence of that being the fact that it can handle the cdp cleanly). The 24db of available gain in the preamp section would boost the 480mv to 7.7 volts (into the power amp section) IF the volume control is turned all the way up. However, John indicated that the 2pm position provided a comfortable listening volume, as did the 10am position for the cdp. I don't see any problem in any of that; all of these numbers, and the volume control settings, seem very reasonable. I note, though, that the Avatar SE specs indicate 60W/channel, while John mentioned 80W/channel. John, can you clarify? Best regards, -- Al |
Kal, please note the word OR between 1.25 mV cartridge output and 80 db gain phono preamp in my previous post. Darkmoebius and Al, actually that link shows that my integrated amp is a VAC Avatar Super, NOT the SE version. Your specs are correct for the SE version, the Super is different. The only spec I can find on the Super is the 80 wpc output in ultra-liniear (no triode option). The Super does use different preamp tubes, different driver tubes, and different power tubes. So I don't think I can use the SE gain specs. My Walker Signature phono stage specs the same as the Reference, and is set for the max gain of 66 db. According to the calculator that Darkmoebius provided, my 0.24 mV cartridge with 66 db of gain outputs a signal of 0.48 V. That would explain the difference in my volume control knob positioning, since my CDP output is 2.5 V, over 5 times the output of the phono stage. Both signals pass through the same line stage and power stage, so I discounted the gain of the integrated amp. Does this help clarify things? Again, thanks for the help. Cheers, John |
- 37 posts total