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Output impedance of the AVP700 too weak?

Discussion in 'Arcam Owners' Forum' started by cpd, Aug 20, 2005.

  1. cpd

    cpd
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    [some edits to restate my questions]

    There is a discussion thread over at AVS about low test tone levels on the AVP700. I have the same issue with mine attached to an Anthem PVA 7 amp. I started to look at the numbers, and now I am concerned that the output impedance may be too weak for my amp to properly drive the signal, or that the input sensitivity is too high. Here are the specs:

    INPUT SENSITIVITY: 1.12 VRMS for 125 W into 8 Ohms
    INPUT IMPEDANCE: 10 kOhms
    VOLTAGE GAIN: 29 db

    Here is a quote from CycloneMike that made me wonder:

    ---
    If I interpret this correctly it takes 700mV of output from the AVP700 to produce 1 watt output of an Arcam P80, versus it taking 1100mV of output to produce 1 watt output from the Sherbourn. I know there are many other factors, but I am trying to be simplistic here as possible.

    I know watt output does not simply equal dB output of speakers; however, it would indicate that the Sherbourn output would only be 700/1100 or 63% in watts as compared to the Arcam amplifiers at the same mV input level.
    ---

    The full post is here: http://www.avsforum.com/avs-vb/showthread.php?p=6059625&&#post6059625

    Chris
     
  2. cpd

    cpd
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    In the same thread linked above, I posted a message that answered my own (and CycloneMike's) concerns. Another guy posted as well. In short: much ado about nothing. 600 ohms is kind of high for a solid state pre-amp, but still within the 10:1 ratio needed for most amps. Looks like it's nothing more than low-level test tones (probably due to the lower input sensitivy ratings for Arcam amps).

    Chris
     
  3. Crustyloafer

    Crustyloafer
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    You might want to check out the release notes for the latest firmware version as there are one or two updates that fix the test tone output level problems. Updates 3.25 and 3.28 in particular address this problem.
     
  4. jakeman

    jakeman
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    I am running the avp 700 with v3.29 and I can confirm the test tone bug has not been fixed.
     
  5. cpd

    cpd
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    Hmmm... I finally got around to upgrading to 3.29 today, and the test tones definitley got louder. Before the update, they were down around 60db and now they come in at about 70 for me. As we've said earlier, the internal test tones are of limited use anyway, but they did make them louder. I do like the lock menu feature too.

    Chris
     
  6. Tamas

    Tamas
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    Hello, how does one go about firmware upgrades without having to take it back to the dealer? Thank you.

    On a similar note, music sounds fantastic - all kinds of music - Def Lep to Dianna Krall.
    Movie soundtracks sound very good as well, especially the centre channel. Voices are very natural and smooth through my Linns.

    Regards, Tom
     
  7. cpd

    cpd
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    My dealer put me in contact with someone "official" who e-mailed me the upgrade files. From there, you just connect the Arcam up to your laptop and run an update program. You should probably at least consult your dealer or you could risk voiding your warranty.

    Chris
     
  8. Tamas

    Tamas
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    I will do that. Thanks cpd.

    Regards, Tom
     

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