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  1. #1
    Junior Member
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    Dec 2019
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    bypassing the preamp and going directly to another power amp

    I'm not an engineer, but I'm trying to get my head around some of the technical information on the wiki so that I don't blow something up. And, I'm stuck at a concept. Can someone help me understand what is being said here? Specifically, with regard to the amplification factor:

    account is too new, so I can't post a link. add the http to the following
    wiki.slimdevices.com/index.php/Connecting_directly_to_a_power_amplifier

    Specifically, the power output and amplifier gain sensitivity section quoted below:
    This table means that the amplifier provides 29dB of gain, or, in other words, amplifies (increases) the line voltage by a factor of 28.2. It also means that if the line voltage offered to the 14B line input is 2.3V, the output voltage is about 65 Vrms. Most importantly, this table means that at 2.3 Vrms on the amplifier line input, the maximum power output of 600W is achieved.
    (emphasis added by me)

    I understand everything about the statement above, except the missing .8 of line voltage factor. I understand the 29db of gain came from the specs of the amp. I understand that if you apply 2.3 line input voltage you get ~65 Vrms by multiplying 2.3v * the 28.2 amplification factor. I just don't understand how you get the 28.2 factor from 29dB of gain.

  2. #2
    Senior Member Jeff07971's Avatar
    Join Date
    Aug 2011
    Location
    London, England
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    1,395
    Quote Originally Posted by dibble View Post
    I'm not an engineer, but I'm trying to get my head around some of the technical information on the wiki so that I don't blow something up. And, I'm stuck at a concept. Can someone help me understand what is being said here? Specifically, with regard to the amplification factor:

    account is too new, so I can't post a link. add the http to the following
    wiki.slimdevices.com/index.php/Connecting_directly_to_a_power_amplifier

    Specifically, the power output and amplifier gain sensitivity section quoted below:
    (emphasis added by me)

    I understand everything about the statement above, except the missing .8 of line voltage factor. I understand the 29db of gain came from the specs of the amp. I understand that if you apply 2.3 line input voltage you get ~65 Vrms by multiplying 2.3v * the 28.2 amplification factor. I just don't understand how you get the 28.2 factor from 29dB of gain.
    Voltage gain in db is 20LogV1/V2 so Gain is 10 raised to the power of 29/20 Ie 10^1.45 = 28.18 odd
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  3. #3
    Junior Member
    Join Date
    Dec 2019
    Posts
    2
    PERFECT! Thanks for a concise answer.

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