When a friend of mine run out of inputs on his preamp, and only phono input was empty/available, i made inverse riaa passive filter for him. So he could use additional line level signal in.
There is severe loss of detail due to additional distortion and noise. If that is what you want sumotan, go for it.
There is severe loss of detail due to additional distortion and noise. If that is what you want sumotan, go for it.
Hi Adason, nope not for me just that I saw this & wondering why. It's like reducing digital output to a LP cartridge level with riaa
& than step up via high gain phono preamp. Yes like you said imagine the among of details being lost.
& than step up via high gain phono preamp. Yes like you said imagine the among of details being lost.
Exactly!
No, nothing digital jagged there.
It does not surprise me when i see 1kHz test signal from cd on scope, looks perfect, smooth with unmeasurable distortion.
What surprise me is that 19kHz or 20kHz looks perfect too! Considering 44kHz sampling...just few points. But this has been explained.
What needs to be said is that dac generates huge amount of junk above 20kHz, because of square wave. This digital junk needs to be sharply filtered. This is detrimental, at least it was in early cd players.
Oversampling takes care of it, since digital junk starts much higher and filter no longer needs to be very steep.
But it took long time to cure digititis.
No, nothing digital jagged there.
It does not surprise me when i see 1kHz test signal from cd on scope, looks perfect, smooth with unmeasurable distortion.
What surprise me is that 19kHz or 20kHz looks perfect too! Considering 44kHz sampling...just few points. But this has been explained.
What needs to be said is that dac generates huge amount of junk above 20kHz, because of square wave. This digital junk needs to be sharply filtered. This is detrimental, at least it was in early cd players.
Oversampling takes care of it, since digital junk starts much higher and filter no longer needs to be very steep.
But it took long time to cure digititis.
The jagged stair-step looking signal of an unfiltered DAC output is not the cause of ‘digital sound’. For one thing, the signal transitions represent ultrasonic content (image-bands), and so are inaudible in and of themselves. They can, however, provoke audible artifacts if they are not handled properly (IMD, bandwidth, slew-rate distortion and such) by the succeeding analog stages in a playback chain. The best practical evidence of the an unfiltered DAC output signal not being responsible for unpleasant digital sound, is the sound of non-oversampling (NOS) filter-free DACs. Which, if you’ve ever heard one, are very natural (analog?) sounding, despite their other faults.
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Addison, very interesting solution, it almost follows the idea of Dolby noise reduction. Boost high frequencies when recording so they lift out of the noise floor and then cut them during playback to reduce the noise even further. What did it sound like? This was ingenious and I don't think should sound cr@p, I think this can be worked on and made into quite something different than just using as an additional input.