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Cambridge Audio Duo Phono Stage Review (Updated)

Rate this phono stage:

  • 1. Poor (headless panther)

    Votes: 4 2.7%
  • 2. Not terrible (postman panther)

    Votes: 10 6.7%
  • 3. Fine (happy panther)

    Votes: 62 41.3%
  • 4. Great (golfing panther)

    Votes: 74 49.3%

  • Total voters
    150

Abdo

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I'm referring to the ground wire that has to go from your turntable to the Amp, not the mains power ground.

Right, left and ground should be coming out of your turntable.

I'm wondering what the noise will be when you've got the three wires between your turntable and your Amp connected.

It may be quieter with it all connected.
does not change when the Rega is connected, the noise signal is the same, and the Rega Planar 1 does not have a ground wire, just the RCA connectors and power cable.
 

Doodski

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Yes, the MA6800's ground is well connected, the ground here is very good, straight from the energy company, everything is new. The Rega, as I showed in the video, is completely disconnected from the MA6800, even to see that the noise is generated by the MA6800 and not by the Rega.
Perhaps shorting the phono RCA inputs will reduce all that noise. <?> Is this safe for a phono preamp???
 

Abdo

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Yes, but the phono preamp is still presented with noise at the input and it will amplify that.
Yes, that's right. Now I just need an answer, is it worth putting a Cambridge Duo or MK3 in this system? (1 million dollar question..lol)
 

Doodski

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Yes, that's right. Now I just need an answer, is it worth putting a Cambridge Duo or MK3 in this system? (1 million dollar question..lol)
The Duo tested very well here @ ASR if memory serves me correct. I will leave the answer to your question to somebody more knowledgeable regarding phono gear. :D
 

LTig

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The Duo tested very well here @ ASR if memory serves me correct. I will leave the answer to your question to somebody more knowledgeable regarding phono gear. :D
Any competently designed phono preamp will add significantly less noise than even the best and cleanest vinyl contains. I would expect the Macintosh to be such a design.

A simple test is to play your cleanest record at the highest loudness level you can handle. Then listen to the noise at a pause between tracks. Lift the arm and listen to the change in noise. If its level drops significantly you're good and a better preamp won't improve SNR.
 

Abdo

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Any competently designed phono preamp will add significantly less noise than even the best and cleanest vinyl contains. I would expect the Macintosh to be such a design.

A simple test is to play your cleanest record at the highest loudness level you can handle. Then listen to the noise at a pause between tracks. Lift the arm and listen to the change in noise. If its level drops significantly you're good and a better preamp won't improve SNR.
Thanks for helping.
Yes, when I raise my arm the noise decreases, I did as you explained. Between the bands, raise your arm.
Now a doubt still persists, could the sound quality with pre-phono (Cambridge duo) be improved?
 

LTig

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Thanks for helping.
Yes, when I raise my arm the noise decreases, I did as you explained. Between the bands, raise your arm.
Ok, then noise is no problem seeking for a solution.
Now a doubt still persists, could the sound quality with pre-phono (Cambridge duo) be improved?
I wouldn't expect it. You have to compare the specs for freqency response. The input capacitance might play a role as well if it is high (more than 100 pF).

Edit: I just read the user's manual of the MC6800. The specs are fine so far and the description of the phono preamp sounds like a very competent design. I would not expect any improvement in sound quality. You might need the Duo if you switch to a low output MC pickup.
 
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Abdo

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Ok, then noise is no problem seeking for a solution.

I wouldn't expect it. You have to compare the specs for freqency response. The input capacitance might play a role as well if it is high (more than 100 pF).

Edit: I just read the user's manual of the MC6800. The specs are fine so far and the description of the phono preamp sounds like a very competent design. I would not expect any improvement in sound quality. You might need the Duo if you switch to a low output MC pickup.
Thank you very much for your reply. What worries me most is buying a product and then it not improving as expected.
And here in Brazil it's not like in the USA where you can simply return it if you don't like it. It's quite complicated here. So that's why I have to research well so I don't spend money on something that won't improve. I appreciate your response.
 
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