Thanks Peter. My DAC communicates with the transport without any problem. I am just thinking if this constant voltage is not dangerous to my DAC when used for a longer time..
I got my birdnest setup running today with the original trafo and a Vishay W02G diode bridge with a Evox-Rifa 1nF cap between each leg. Two Panasonic FC 1000uF / 25V caps and a MC7808C regulator. The C916 was replaced with a Panasonic FC 22uF / 100V cap.
The two output resistors were just some old ones taken from the drawer.
The 5 components suggested by Peter was removed.
The transport is feeding a DPA Enlightenment DX32 DAC.
It´s cool when it works the first time, but I can´t comment on the sound yet until I try it up against my DPA transport.
The two output resistors were just some old ones taken from the drawer.
The 5 components suggested by Peter was removed.
The transport is feeding a DPA Enlightenment DX32 DAC.
It´s cool when it works the first time, but I can´t comment on the sound yet until I try it up against my DPA transport.
any reason why u need such a large deviation from the original value for C916?
Thanks Peter. You provide solid, easy-to-follow guidelines for this project.
If I may, I suggest putting a .27Ohm - .47Ohm 2-5 Watt resistor between the LM7808 V+output and the 1,000uF-470uF decoupling cap that follows it. LM78xx regulators are notorious for oscillating into low impedance loads and a low impedance cap like a large value Black Gate or Rubycon (esp. with a bypass) after a commercial regulator will result in oscillation. The added benefit of this resistor will be to provide a last low-pass RC filter for the supply before it reaches the active components. The resistor does not need to be low-inductance, in fact, inductance would add further HF filtering, which would be beneficial here.
If I may, I suggest putting a .27Ohm - .47Ohm 2-5 Watt resistor between the LM7808 V+output and the 1,000uF-470uF decoupling cap that follows it. LM78xx regulators are notorious for oscillating into low impedance loads and a low impedance cap like a large value Black Gate or Rubycon (esp. with a bypass) after a commercial regulator will result in oscillation. The added benefit of this resistor will be to provide a last low-pass RC filter for the supply before it reaches the active components. The resistor does not need to be low-inductance, in fact, inductance would add further HF filtering, which would be beneficial here.
Help
That is my exact problem....
So excuse me for being 'a bit of a thicky' (there is no excuse really!) but... the (0.01uF or similar) cap goes across DOUT and GND after the output resistors? Or in line on DOUT?
DAC locks on to other sources OK. Using the built in DAC in an Onkyo Integra A-701 for now.
I can only think of electronics by using plumbing analogies, this will only get me so far I guess!
I'll probably have found out by the time anyone answers..... I'm on Japan time and at the start of the Labour Day holiday here.
regards all
Bill
That is my exact problem....
So excuse me for being 'a bit of a thicky' (there is no excuse really!) but... the (0.01uF or similar) cap goes across DOUT and GND after the output resistors? Or in line on DOUT?
DAC locks on to other sources OK. Using the built in DAC in an Onkyo Integra A-701 for now.
I can only think of electronics by using plumbing analogies, this will only get me so far I guess!
I'll probably have found out by the time anyone answers..... I'm on Japan time and at the start of the Labour Day holiday here.
regards all
Bill
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Thanks Peter,
I tried that and still no lock. DAC still locks to another source all other things (cables) being equal.
I'm still using dubious output resistors (measured values are close to 300 and 100 Ohms) I had lying around, I'll try swapping them out for the better ones I acquired.
Any thing else to look for folks?
thanks
Bill
Bill,
At a certain moment while tweaking mine I experienced a lock problem because I had some power supply cap leads crossing over the SPDIF wires. When it happened, a friend of mine suggested me to keep other voltage source far from SPDIF wires. Moving them away a few mm cured the sync problem right away.
At a certain moment while tweaking mine I experienced a lock problem because I had some power supply cap leads crossing over the SPDIF wires. When it happened, a friend of mine suggested me to keep other voltage source far from SPDIF wires. Moving them away a few mm cured the sync problem right away.
Yes, I am suspecting some other problem to turn up....
The analogue outputs from the on-board DAC are fine (I've heard worse, to clarify) I should check Dout traces back to the chip I guess. If I scope the SPDIF signal what kind of trace should I expect at what settings? I can play a test disk 1K square wave or something... Asking basic questions I know
Tried moving signal and power lines seperate.
I should swap out those output resistors next....
Or start 'divining' with a coat hanger perhaps!
No..., that approach is for much later in the day!
I appreciate all the help and advice thanks! Hope this may help some other 'electronically challenged' music lover in future.
Bill
The analogue outputs from the on-board DAC are fine (I've heard worse, to clarify) I should check Dout traces back to the chip I guess. If I scope the SPDIF signal what kind of trace should I expect at what settings? I can play a test disk 1K square wave or something... Asking basic questions I know
Tried moving signal and power lines seperate.
I should swap out those output resistors next....
Or start 'divining' with a coat hanger perhaps!
No..., that approach is for much later in the day!I appreciate all the help and advice thanks! Hope this may help some other 'electronically challenged' music lover in future.
Bill
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