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Steno wrote:Hi NicMac,
I'm going to compare the two solutions, so I'll keep you informed about my tests. But I need to wait for al least 2 months because Buffalo II, Placid and Legato are on their way to my home. :-) I too have no experience with transformer, but I think it should be the best way to do the I/V conversion, no active components, no selected and matched components, no power supply issues. Sure enough, the transformer must be designed and made very well.
Stefano The transformer, unless it has vanishingly low primary impedance, will not really be doing I/V conversion, as the ES9018 will be acting as a voltage source rather than a current source. I'm sure you can still achieve good results, but I just want to be clear about the technical aspects. The advantage of an active stage is the ability to have an input impedance in the mOhm range, allowing the ES9018 to act as a current source, and achieving it's best potential performance.
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Thanks a lot...so the Es9018 change its behaviour depending on the impedance seen at OUT+ / OUT-. Why it performs better as current source than voltage source?
Thanks again!
Stefano
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Nic,
You da man, pretty much sum up the character of the b-ii with passive trannie I am hearing, might consider a tube buffer with unity gain, do you reckon that would resolve the hum from propogating from source to amp?
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klo,
I haven't got a clue. I'm not into trannies nor tubes.....
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Steno wrote:Thanks a lot...so the Es9018 change its behaviour depending on the impedance seen at OUT+ / OUT-. Why it performs better as current source than voltage source?
Thanks again!
Stefano The behaviour is the same; the characteristics are better if you fix the voltage at the output (ie, use it in current mode). According to the ESS white paper, this is due to the fact that the polysilicon resistors in the chip have a voltage coefficient and using it in current mode cancels it out.
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Hi, I am getting two different measurement across the two B-II Out+ and Out- one side is 65mV and the other 86mV. Is there any reason for the voltage difference? Thanks. Edited by user Monday, February 21, 2011 9:26:34 AM(UTC)
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Could be any number of explanations, most likely is a difference in load.
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Russ White wrote:Could be any number of explanations, most likely is a difference in load. This is measured without load. Do I need to ensure the voltage measurement match both channels?
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Russ White wrote:Just to be clear. As long as the primary is not connected to GND it is perfectly ok to use +OUT and -OUT, one into each lead of the primary. When done this way there will be no differential DC, but there will be ~1.65V common mode DC.
You would not want to use just +OUT and GND unless you use a capacitor to block the DC.
You also would not connect +OUT and -OUT to the same lead (short them). Hi Russ, I am getting the hum with the +OUT and -OUT connection but if I connect +OUT and GND to the primary, the hum is gone, can I short GND and -OUT? Thanks.
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Quote:can I short GND and -OUT No.
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