post15983
Before I list the many corrections, does anyone else think it is correct as shown?
I don't like this layout.
Before I list the many corrections, does anyone else think it is correct as shown?
The Designer thinks it's good.
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I can't speak to "correct" but that diagram shows almost exactly how I built mine, and I have had no issues with grounding or noise. The only differences are that I do not have a capacitor across the resistor/diode network that isolates 0V from PSU chassis and safety ground (that looks like a good idea though, to create a lower impedance path to ground for very high frequencies; or would it create a path of ingress for RF?), and the shield(s) of my DC umbilical cable is connected to the connector shell and thereby to the PSU chassis (rather than directly to the safety ground as shown in that diagram, but effectively the same).
The TT ground post on the phono preamp chassis is the only place the two 0V lines connect directly.
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Just to be clear: Andrew I respect your analyses of grounding and safety issues and have learned a lot from you about these things. I would very much like to read your list of corrections and your thinking about why the diagram is lacking. My earlier comment was only to say that I am not hearing any problems, but of course I am open to suggestions for improvement.
Use file from BinkAudioTestCD. Few of them reach 2v Rms (on scope viewing). After nearly 15h, harshness is the high is almost entirely gone.
The cartridge (DL110) tracking weight was 1.6g, fixed it to 1.8g.
C2 is lesser than 15 nF, I need about 620pF to reach 15.2
The best value for Rload is about 5k, 47k is too "bright", but i will try again when C2 will be adjusted.
Seems the SCR FEP cap is worth a try
I want to hear, particularly from Members who have built using a scheme similar to that post15983, on why they did it that way.
There may be something of merit in Alex's method.
I took on board your comments. But noted you did change the wiring.
But to me that post15983 just looks completely wrong.
There may be something of merit in Alex's method.
I took on board your comments. But noted you did change the wiring.
But to me that post15983 just looks completely wrong.
I have downloaded the three doc in post1.
None show Alex's grounding layout.
Where is the doc that shows the grounding you are referring to?
Use file from BinkAudioTestCD. Few of them reach 2v Rms (on scope viewing). After nearly 15h, harshness is the high is almost entirely gone.
The cartridge (DL110) tracking weight was 1.6g, fixed it to 1.8g.
C2 is lesser than 15 nF, I need about 620pF to reach 15.2
The best value for Rload is about 5k, 47k is too "bright", but i will try again when C2 will be adjusted.
Seems the SCR FEP cap is worth a try
Less than 15nF C2+CY total is surely making it brighter than normal, so its not only due to the SCR or the loading value. Lacking 620pF seems kinda much. Are you using a trusty meter? Anyway, you will find the tonally neutral value by trial. Have some 100pF capacitors to can add them step by step while judging your preferred tone.