Brian, Russ
I've just finished installing my WM8804 module in my Musical Fidelity A5 DAB tuner (so that I can use the DAC stage independently of the digital tuner module).
I had some fun getting noises from it until I realised I was using the data out terminal instead of data in! Oops!
It sounds great! Very well put together.
By the way, it works quite happily off a 5V supply.
I've just finished installing my WM8804 module in my Musical Fidelity A5 DAB tuner (so that I can use the DAC stage independently of the digital tuner module).
I had some fun getting noises from it until I realised I was using the data out terminal instead of data in! Oops!
It sounds great! Very well put together.
By the way, it works quite happily off a 5V supply.
traf said:
Yes the receiver will work fine off 5V because its a 3.3V circuit with LDO VREGs.
The DAC on the other hand is 5V and needs something like 250mv drop minimum. So 5.25V would work, but is not optimal. A higher drop produces better regulation. Thats why I recommend at least 6.5V.
Cheers!
Russ
Power supply note.
Here is an important factoid about the Opus DAC. The Digital supply should not be allowed to ever be above the analog supply. Now I know I designed the PCB two accept two separate DC inputs for both VREGs, but honestly the safest thing to do is to run both of the DC input from a single supply. Thats way both voltage decay at the same rate at power down.
If VD exceeds VA at power down you can get some nasty chirps.
So my recommendation is this. With the LCPS (or soon to be released LCDPS) use one supply for the DAC and one for the receiver. Or for dual mono you could even use one supply for each mono DAC.
Also, run the wires from the terminals direct to the PS, do not daisy chain.
One other thing you can do is add a load to the VD supply at the input (say 221R resistor) to ensure that the digital supply decays first.
See, building one of these things is not as trivial as it may seem. But it sure is fun. 🙂
Cheers!
Russ
Here is an important factoid about the Opus DAC. The Digital supply should not be allowed to ever be above the analog supply. Now I know I designed the PCB two accept two separate DC inputs for both VREGs, but honestly the safest thing to do is to run both of the DC input from a single supply. Thats way both voltage decay at the same rate at power down.
If VD exceeds VA at power down you can get some nasty chirps.
So my recommendation is this. With the LCPS (or soon to be released LCDPS) use one supply for the DAC and one for the receiver. Or for dual mono you could even use one supply for each mono DAC.
Also, run the wires from the terminals direct to the PS, do not daisy chain.
One other thing you can do is add a load to the VD supply at the input (say 221R resistor) to ensure that the digital supply decays first.
See, building one of these things is not as trivial as it may seem. But it sure is fun. 🙂
Cheers!
Russ
Re: Power supply note.
Actually forget this, it does not seem to work. 🙂 in any case, if you don't notice any issue, then don't change anything. 🙂 I only mentioned this fact from the data sheet out of an abundance of caution.
Cheers!
Russ
Russ White said:
Actually forget this, it does not seem to work. 🙂 in any case, if you don't notice any issue, then don't change anything. 🙂 I only mentioned this fact from the data sheet out of an abundance of caution.
Cheers!
Russ
Ah OK, I am pretty sure I found what was causing my chirp issue. it was the fact that I am running a microntroller off the same supply as the DAC, I isolated the microcontroller supply and my turn off chirp is gone.
I am using the microcontroller on my test rig to adjust volume etc. It works very well, but the DAc is directly coupled to my amp, so it is very sensitive, but man it sounds awesome. 🙂
Man I wish I were in Munich, I hear its Oktoberfest time around there...
Cheers!
Russ
I am using the microcontroller on my test rig to adjust volume etc. It works very well, but the DAc is directly coupled to my amp, so it is very sensitive, but man it sounds awesome. 🙂
Man I wish I were in Munich, I hear its Oktoberfest time around there...
Cheers!
Russ
Re: Re: Static when cd starts or ejects...
Swapped out the Sony NS500 for a Phillips CD80 and there
is no static on startplay/ejects? Will have to listen later for
sonic differences.
Russ White said:
Swapped out the Sony NS500 for a Phillips CD80 and there
is no static on startplay/ejects? Will have to listen later for
sonic differences.
Ballsie
Ok, I am a bit taken aback - the Ballsie comes with 2 bags of caps - 12 total - are these needed conditionally or ???
Ok, I am a bit taken aback - the Ballsie comes with 2 bags of caps - 12 total - are these needed conditionally or ???
Power Supply question
Hi,
i tried to google and read the thread but did not find a simple question to my complex answer (other way round):
I am going to use this DAC in combination with a M3 headphone amp - the amp ist not very important despite the fact that it uses some virtual ground, using a TLE2426.
I only want to use one 24V transformer to generate 24v (headamp and ballsie) and something like two 14V power supply (to generate 7v for digital and analog power supply for the dac).
Now I am thinking and fiddling a way to get a clean 7v output regarding to the VGND of the TLE2426 (since this will be most probably GND of the signal - having a different signal ground than the VGND of the amp will most probably not very nice to the VGND - because then I will draw VGND somewhere lower/higher than 24V/2 - isn't it?)
Any ideas? I was thinking of using two opamps or buffers to buffer the vgnd (for VGND of the A/DVCC) - but does this give me any certainity that it will be in the middle of the 14V supplies? Theoreticall, regarding to my thinking (no experimentation done yet) - it should work.
Does anybody got a good idea to solve this puzzle (despite using a second transformer 😉 )?
Hi,
i tried to google and read the thread but did not find a simple question to my complex answer (other way round):
I am going to use this DAC in combination with a M3 headphone amp - the amp ist not very important despite the fact that it uses some virtual ground, using a TLE2426.
I only want to use one 24V transformer to generate 24v (headamp and ballsie) and something like two 14V power supply (to generate 7v for digital and analog power supply for the dac).
Now I am thinking and fiddling a way to get a clean 7v output regarding to the VGND of the TLE2426 (since this will be most probably GND of the signal - having a different signal ground than the VGND of the amp will most probably not very nice to the VGND - because then I will draw VGND somewhere lower/higher than 24V/2 - isn't it?)
Any ideas? I was thinking of using two opamps or buffers to buffer the vgnd (for VGND of the A/DVCC) - but does this give me any certainity that it will be in the middle of the 14V supplies? Theoreticall, regarding to my thinking (no experimentation done yet) - it should work.
Does anybody got a good idea to solve this puzzle (despite using a second transformer 😉 )?
Re: Power Supply question
I am sorry if I can't follow your post very well. But let just say I understand exactly what you want to do (which would be a stretch) I would strongly suggest you do not do it.
Even though you said you did not want to, I personally would just get another small trafo. What you suggest may work, but I would not bother as the risk reward ratio seems highly weighted toward risk. 🙂
You could probably make a more complicated solution work, but there are a lot of "gotcha's" hidden in there. 🙂
Cheers!
Russ
_atari_ said:
I am sorry if I can't follow your post very well. But let just say I understand exactly what you want to do (which would be a stretch) I would strongly suggest you do not do it.
Even though you said you did not want to, I personally would just get another small trafo. What you suggest may work, but I would not bother as the risk reward ratio seems highly weighted toward risk. 🙂
You could probably make a more complicated solution work, but there are a lot of "gotcha's" hidden in there. 🙂
Cheers!
Russ
Re: Re: Power Supply question
Sorry for my bad description - it was a image of the complexity i fell in this 😉
But probably you are right - there is no way around using two transformers. Originally I wanted to use some ac/ac wall plug transformer for lightning (they are cheap and far away from the equipment 😉 - now it most probably has to go into the case.
Thanks for your great support!
Russ White said:
Sorry for my bad description - it was a image of the complexity i fell in this 😉
But probably you are right - there is no way around using two transformers. Originally I wanted to use some ac/ac wall plug transformer for lightning (they are cheap and far away from the equipment 😉 - now it most probably has to go into the case.
Thanks for your great support!
multiple inputs
Russ, if I wish to use both S/PDIF and USB modules at the same time, can I just connect the two and only use one at the time, should I use swtiches? What is the solution if i wish to use more than one input?
Thanks in advance!
Russ, if I wish to use both S/PDIF and USB modules at the same time, can I just connect the two and only use one at the time, should I use swtiches? What is the solution if i wish to use more than one input?
Thanks in advance!
Re: multiple inputs
I would suggest a switch or a relay for now. 🙂 A 4PDT relay or switch would work fine.
We are also working on a 4 -1 multiplexer, but its not quite ready yet.
Cheers!
Russ
MASantos said:
I would suggest a switch or a relay for now. 🙂 A 4PDT relay or switch would work fine.
We are also working on a 4 -1 multiplexer, but its not quite ready yet.
Cheers!
Russ
thanks, I don't want ot complicate and increase the price using the 4:1 "switch" module so a nice 4pdt switch will it!
Russ, I have another question:
Is there any advantage in using a line filter in the power input? I'll be using the OPUS in a room with quite a few computers, and other electronic and electric gear. I believe it is worth it, but I could use a second opinion.
Thanks in advance!
Is there any advantage in using a line filter in the power input? I'll be using the OPUS in a room with quite a few computers, and other electronic and electric gear. I believe it is worth it, but I could use a second opinion.
Thanks in advance!
MASantos said:
Well it can't hurt. The PS and power arrangement on the opus modules have excellent line rejection, but as always, the cleaner the AC the better. 🙂 Be cautious though, some line filters actually do next to nothing to clean up the AC. You can spend thousands on a true line conditioner, but in the end probably not see much effect. 🙂
Cheers!
Russ
I am considering using a power input module with built in filter for shurter. I have used their products before of audible results in power supplies. I gess I'll go ahead. It's only 10$ more anyway.
MASantos, how's your DAC coming along?
I hope it doesn't come of as inappropriate, but I'm also from Lisbon, any chance I could hear your DAC....?
Cheers
I hope it doesn't come of as inappropriate, but I'm also from Lisbon, any chance I could hear your DAC....?
Cheers