You just connect the input of the output buffer straight to the hold capacitor, no need for extra switches.
Gate and capacitor oxide leakage can be very small when the oxide is thick enough, otherwise EPROMs and flash memories couldn't work. You could also keep the PMOS biased slightly on to make its resistance more predictable and process- and temperature-independent. To get a cut-off frequency below 1 Hz with a capacitance that still fits on chip, say 100 pF, you need an on resistance of at least 1.6 Gohm. You get that in weak inversion at the same VGS that would give a saturation drain current of at most 16 pA.
Gate and capacitor oxide leakage can be very small when the oxide is thick enough, otherwise EPROMs and flash memories couldn't work. You could also keep the PMOS biased slightly on to make its resistance more predictable and process- and temperature-independent. To get a cut-off frequency below 1 Hz with a capacitance that still fits on chip, say 100 pF, you need an on resistance of at least 1.6 Gohm. You get that in weak inversion at the same VGS that would give a saturation drain current of at most 16 pA.
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Packaging and connections
Some solutions I’m exploring. I strapped the clock and a doubler together with the tops of the cases compressing a conformal pad. This stops any vibration of the lids and dampens the whole unit quite nicely. Added special soft feet to the edge so that the actual xtall rests in an on edge, rather than flat orientation surrounded by foam inside to stabilize air currents and thus temperature. In the next picture a Twisted Pear Cronus was assembled in inverted order such that the Cronus board is on top. I also mounted the jumpers on the bottom to provide unobstructed mounting of the squaring circuitry. The sound is so wonderful that I haven’t moved it from the actual breadboard into a case yet.
Sorry I don’t know how to rotate pictures.
Some solutions I’m exploring. I strapped the clock and a doubler together with the tops of the cases compressing a conformal pad. This stops any vibration of the lids and dampens the whole unit quite nicely. Added special soft feet to the edge so that the actual xtall rests in an on edge, rather than flat orientation surrounded by foam inside to stabilize air currents and thus temperature. In the next picture a Twisted Pear Cronus was assembled in inverted order such that the Cronus board is on top. I also mounted the jumpers on the bottom to provide unobstructed mounting of the squaring circuitry. The sound is so wonderful that I haven’t moved it from the actual breadboard into a case yet.
Sorry I don’t know how to rotate pictures.
No sand in the boxes? Too bad, that would definitely improve the sound.
Sand from the Kalahari desert has a special sonic signature and it is highly recommended. No Nevada, Mururoa atoll or Kazakhstan sand, that could be slightly radioactive and affect the sound by ionizing the air between the sand grains.
Sand from the Kalahari desert has a special sonic signature and it is highly recommended. No Nevada, Mururoa atoll or Kazakhstan sand, that could be slightly radioactive and affect the sound by ionizing the air between the sand grains.
Pictures that rotate unintendedly are often related to the EXIF header of modern JPEG files, which is supported by some programs and not by others. I usually solve it with a free command line program called jhead, giving the command jhead -autorot *.jpg or jhead -purejpg *.jpg
Maybe the sand of the Kalahari desert could even improves your oscillator.
You should give it a try.
I am sure that he has already tried that and of course with a subsequent double blind test. is there a shop that sells Kalahari sand? I couldn't find one yet.
Result is good, easily sounds better to me than using I2SoverUSB clocks. However, my dac chip needs 22/24MHz clocks, so I used a frequency multiplier chip to produce the 45/49 MHz clocks needed by I2SoverUSB. Then I reclock I2S signals coming out of I2SoverUSB to attenuate any jitter caused by the frequency multiplier. Also, I found that using Andrea's clocks at 11/12 Mhz (along with Andrea's frequency doublers) produced slightly better sounding (to me) 22/24MHz master clocks, as opposed to earlier having tried Andrea's clocks directly with 22/24 Mhz crystals.
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I am interested in this mod as well. I was considering to feed Andreas clock via the external oscillator board and STS but the high frequency rate 45/49 made me discard it, I just have the 5/6 and two doublers. However I didn´t know that frequency could be changed after a firmware update, would it be possible to use 11/12??
Actually I wanted to mod the usb hub controller using the 24Mhz external clock (NS3) of my usb card but I think it is SMSL USB3317 that uses 26Mhz, so no go....
Actually I wanted to mod the usb hub controller using the 24Mhz external clock (NS3) of my usb card but I think it is SMSL USB3317 that uses 26Mhz, so no go....
Could someone describe what is meant by I2S over usb? I thought that usb had its own clock and that audio stream(s) were packeted to travel over it. I have experience with a usb to I2S converter that derives its audio clocks from the usb master clock. Yes improving the usb clock made a difference, but switching to a fifo or an amenero that could be fed external audio master clock sounded far superior to any improvement in the usb clock, while rendering such improvements to the usb clock moot.
"Could someone describe what is meant by I2S over usb?"
Its all one word: I2SoverUSB -- I2SoverUSB - I2S over USB Audio
Its all one word: I2SoverUSB -- I2SoverUSB - I2S over USB Audio
Yes, we have used the 74AC04 because it has the best phase noise performance.
We have tried almost all logic families and the AC was 10-15 dB better.
And not all the brands, TI and On-Semi devices have worse phase noise than the brand we have used.
Although someone think that the beaty of the waveform is crucial, it has nothing to do with the phase noise.
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