I don't know about the phase noise of a 50 cents oscillator, I assume 10-20 dB worse than the Crystek.
Typical phase noise analysis are in the 0.1 to 100 kHz bandwidth, although in audio the close in noise is crucial we also have to look at the whole sprectrum because the noise above 10 Hz from the carrier can affects the digital to analog conversion modulating the output in audio band. The noise will be mixed in the DAC and the results are unpredictable.
I wouldn't be happy with so high noise, I would look at the reason causing the noise to remove it. There are no physical reasons to get this noise when the master clock is free of that. I would investigate and solve the issue.
There is no question that I found a gamechanger (technical term) improvement in sound quality by replacing an NDK SDA oscillator with your 45 MHz Driscoll. Also clear improvement with oven vs room temperature. All of this on the FIFOPi connected to a 25 year old TDA1541a chip. I have faith that the 5 MHz will be worth the effort. If in the future, there is an even better FIFO, then we'll look at that as another incremental upgrade option. For now, I'm enjoying the music.
Can you share the dimensions of the new PCB's? I am curious if I can fit them into an existing chassis.
At some point before we have to commit to the GB, it will be great to see a comparison chart of the Differential vs other. Size, voltage, performance and BOM cost. Right now for me it would simply be a coin toss to decide which route to take. I am not even sure why you'd go to the trouble to offer both as they appear interchangeable. So maybe someone smarter than I can explain. thanks
Well, to analyze this, we or at least me, need a 24Mhz oscillator for an upcoming ADC implementation, while the current used HW (marketing jitter compared to marketing bits
) has a large crystal & PLL signature. Even connected with additional HW connected as a de-jitter burg Currently also measure & compare why a Carbon CD-R burned in 1X Master Mode sounds better then a ordinary silver on 8x speed.
So please do not forget the use on ADC's
Also the FiFo implementation with Cross Link (back to the source to avoid sample under/overruns) would may the only implementation, to completely get ride of low freq. movements, where the PLL will not (IMHO)
So I am tuned for the new Driscoll schema at 24 MHz ...
Hp
PCB size is 75 x 151 mm, the box we have choosen is the Hammond 1455J601.
The comparison plot between the Differential and the Driscoll oscillators has been published in post #2580.
I will publish all the BOM soon, we are now testing the frequency doubler.
Both Differential and Driscoll oscillator need 12 to 18 VDC, batteries (suggested) or low noise linear regulator.
The cost has not yet been definitively decided because it will depend on the number of components we have to solder by hand (finished board), but we are thinking to offer a semi finished board, with the most parts assembled at a lower price (all the through hole and a few SMD parts to be assembled).
Soldering components by hand take long time and we have little free time to spend assembling the finished boards.
When we started building the new oscillator we had not idea about the best circuit to implement, so we have decided to develop a pair of devices, we don't knew what performance to expect from both.
Only after the measurements and several iterations of circuits and layouts we have discovered that they perform very similar.
The comparison plot between the Differential and the Driscoll oscillators has been published in post #2580.
I will publish all the BOM soon, we are now testing the frequency doubler.
Both Differential and Driscoll oscillator need 12 to 18 VDC, batteries (suggested) or low noise linear regulator.
The cost has not yet been definitively decided because it will depend on the number of components we have to solder by hand (finished board), but we are thinking to offer a semi finished board, with the most parts assembled at a lower price (all the through hole and a few SMD parts to be assembled).
Soldering components by hand take long time and we have little free time to spend assembling the finished boards.
When we started building the new oscillator we had not idea about the best circuit to implement, so we have decided to develop a pair of devices, we don't knew what performance to expect from both.
Only after the measurements and several iterations of circuits and layouts we have discovered that they perform very similar.
I know, but please remember that we have a job and a life, we are not professional so our times are inevitably very long.
Moreover at the same time we are developing several devices (oscillators, doublers, FIFO, battery supply, DAC and so on) therefore the times inevitably get longer.
Stay tuned!
Moreover at the same time we are developing several devices (oscillators, doublers, FIFO, battery supply, DAC and so on) therefore the times inevitably get longer.
Stay tuned!
@G600
I did not mean that you complained, I just wanted to say that I'm sorry for such a long time, I would like to have everything ready.
Unfortunately the development of high performance devices needs several iterations of circuits, PCB layouts and measurements.
That's the reason I hope most members will get the semi finished boards avoiding us to spend time soldering the components, so we can focus to the development.
I did not mean that you complained, I just wanted to say that I'm sorry for such a long time, I would like to have everything ready.
Unfortunately the development of high performance devices needs several iterations of circuits, PCB layouts and measurements.
That's the reason I hope most members will get the semi finished boards avoiding us to spend time soldering the components, so we can focus to the development.
Andrea you said that the Driscool oscillator was not very sensitive to power supply,I thought to feed it with a Salas SSLV1.3 shunt reg,What do you think,
what voltage is needed for the frequency doubler.
Andrea,
Possibly the reason no one answered is that your not asking real "questions" - as you already know the answers (or you should do)...these are "leading" questions and your not educating anyone like this, but instead you come across as rather childish and rather insulting...
Your doing fine work experimenting and developing these clock circuits with the aid of your colleagues' TimePod (or maybe you have purchased your own unit by now) - but please try to remain humble and respective of others who are not lucky enough to have the access to such equipment to develop there own designs as far as you have been able too.
Its the learning that makes life interesting
With the 100k euro you have from people who funded the yet to be delivered MDAC 2 I am surprised there is any equipment you don’t have. I trust that this debate and offers to measure kit isn’t interfering with the delivery date, which is currently about six years late.
It would be a big help for the ones who can solder themselves if you can make a standard parts list at mouser.
This will make it easy to purchase all the needed parts (it will persuade me to buy the bare boards instead of the finished ones)
I has cost me quite some time to order all the parts for the previous driscoll boards out of the supplied parts lists, there were also some parts not available and that makes it hard to find an alternative if you are not sure what the important component features are.
A parts list with all combinations can be made on mouser website and easily shared. For the specific frequency dependent parts a note can be added so the buyer can delete all unneeded parts.
Please take this into consideration.
Regards,
You can use the Salas shunt, both oscillators and doublers need 12 to 18 VDC.
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