Re: Successful Frustration [message #97796 is a reply to message #97793] |
Sun, 23 June 2024 21:29 |
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gofar99
Messages: 1949 Registered: May 2010 Location: Southern Arizona
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Illuminati (5th Degree) |
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Hi, It is true that the ears were better a while back. However that was not the issue. I had goals in frequency response, distortion, signal to noise and most importantly making the designs diy friendly. Essentially, I accomplished them about 5 years ago and have been tweaking a bit since then. I felt that it was possible to improve the S/N a bit even though it was really just fine at about -85 (inaudible) or so in all designs. By careful adjustments and indeed some changes in the designs I got all past -90 and some nearly to -100 (all in dbv wide band). BTW a comprehensive test project is still ongoing in the power supply area. I made a sophisticated test set up to try variations of transformers, SMPS, AC to DC supplies, all sorts of filters and such using one of the phono preamps as a test device. This way I can actually measure the effects of any combination to see the merits or deficiencies in regard to the performance of an actual audio device. It will take some time as I figure there are over 100 possible combinations that are possible. So far, the best has been an AC to DC SMPS for the heaters and an Edcor transformer with a bridge rectifier and 6 R/C pi sections. I will show the results on the web when I have finished. So short of engaging in something new I am temporarily at a standstill for other stuff.
Good Listening
Bruce
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