Hi,
I have a Sony 777es CD Player with an output of 2v RMS and an Load Impedance of 10k Ohms feeding a Lightspeed Attenuator then going to a pair of modified McCormack DNA 0.5 monoblocks with an input Impedance of 10K Ohms. As far as I can understand this will not work. The Lightspeed is on its way from Australia so I haven't been able to try it out. It will be powered by a wall wart.
The part I'm having trouble with is from the wall to the output of the buffer. I thought I had it but obviously I don't. My thoughts were K-Multiplier> Kuartlotron (with selector switch no volume control)>amp. Can someone walk me through it
110v>power supply>K-Multiplier>Kuartlotron.
I can solder pretty well and follow a circuit layout especially if it is on a PCB but I cannot figure out what values are in a circuit ie v & I.
Thanks,
Alan.
I have a Sony 777es CD Player with an output of 2v RMS and an Load Impedance of 10k Ohms feeding a Lightspeed Attenuator then going to a pair of modified McCormack DNA 0.5 monoblocks with an input Impedance of 10K Ohms. As far as I can understand this will not work. The Lightspeed is on its way from Australia so I haven't been able to try it out. It will be powered by a wall wart.
The part I'm having trouble with is from the wall to the output of the buffer. I thought I had it but obviously I don't. My thoughts were K-Multiplier> Kuartlotron (with selector switch no volume control)>amp. Can someone walk me through it
110v>power supply>K-Multiplier>Kuartlotron.
I can solder pretty well and follow a circuit layout especially if it is on a PCB but I cannot figure out what values are in a circuit ie v & I.
Thanks,
Alan.
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The Sony has a low output impedance of 110 Ohms.
The Lightspeed Attenuator needs a source impedance of 1k or less.
This will be fine.
The amplifiers have a rated input impedance of 100k, while the
Lightspeed Attenuator needs over 33k loading. This will be fine.
The input matching for the Lightspeed is fine, so the Sony is not an issue. The 10k is just
a standard IHF load spec, the Sony can drive lower loads than 10k.
Check with George to see if the mod amplifier is too low in input impedance to be acceptable as a load.
Optus Member Website - georgehifi
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George got back to me very quickly and said that it will be OK. He based this on a Stereophile review of the XA777ES which is a later version of my SCD777ES so I'm not sure they are exactly the same, we will see.
Acass,
you were mixing up input impedance, load impedance, source impedance and output impedance.
The output of a Source has an Output Impedance. Some refer to this as Source impedance, the impedance seen by the Receiver looking back towards the Source.
The input of a Receiver has an Input Impedance. Some refer to this as a load impedance, the load seen by the Source looking forward towards the Receiver.
The Sony being a SOURCE component will have it's own Output Impedance and usually Sony will specify a range of suitable loads that will work with their equipment. They will probably refer to these as suitable/recommended loads.
The 10k you saw is the minimum recommended load impedance. But anywhere from 10kohms to 200kohms will work.
Rayma seems to have looked at some data for you and found the Output Impedance to be 110ohms. This is also the Source Impedance as seen by the Receiver.
Is that any clearer?
you were mixing up input impedance, load impedance, source impedance and output impedance.
The output of a Source has an Output Impedance. Some refer to this as Source impedance, the impedance seen by the Receiver looking back towards the Source.
The input of a Receiver has an Input Impedance. Some refer to this as a load impedance, the load seen by the Source looking forward towards the Receiver.
The Sony being a SOURCE component will have it's own Output Impedance and usually Sony will specify a range of suitable loads that will work with their equipment. They will probably refer to these as suitable/recommended loads.
The 10k you saw is the minimum recommended load impedance. But anywhere from 10kohms to 200kohms will work.
Rayma seems to have looked at some data for you and found the Output Impedance to be 110ohms. This is also the Source Impedance as seen by the Receiver.
Is that any clearer?
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Andrew you are dead right I'm mixing everything up. I can't even convey what I read in the specs right.
Luckily the Lightspeed is completed and will be powered by a very expensive Wallwart from Music Direct.
I think my problems have been compounded by reading about buffers for a week and coming up with the wrong picture.
Any help is most welcome.
Cheers Alan.
Luckily the Lightspeed is completed and will be powered by a very expensive Wallwart from Music Direct.
I think my problems have been compounded by reading about buffers for a week and coming up with the wrong picture.
Any help is most welcome.
Cheers Alan.
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