Hi Chanh,
Thank you for your elaborate answer. I am running raspberry pi with the latest runeaudio and control with mpad. This works perfect for me. I use a trick for loading the cover art on mpad; I have a second dddac playing with an alix streamer through my old wave io. The alix is running mpdpup and when connecting mpad to this unit the local cover art is always loaded automatically to mpad, and as I use local storage on the ipad it can also be used when controlling other streamers in the house that source from the same music database on my NAS. I have some terabytes of music stored on my NAS.
Mpad is also more responsive than the webui of volumio/runeaudio.
I just recieved my ufl connection board for the bbb and am finishing the acko reclocker so there will be some aural improvements this christmas period
Than some pin 20 tweaking (have to desolder the board stack and that's holding me back a bit)
I think that my music source is than kind of finished.........
At least for the time being and untill the botic cape comes out or I get bored......
My amps are (in my humble opinion) of excellent reference quality so I am now concentrating on a new loudspeaker project.
It keeps the audio nut of the streets
Thank you for your elaborate answer. I am running raspberry pi with the latest runeaudio and control with mpad. This works perfect for me. I use a trick for loading the cover art on mpad; I have a second dddac playing with an alix streamer through my old wave io. The alix is running mpdpup and when connecting mpad to this unit the local cover art is always loaded automatically to mpad, and as I use local storage on the ipad it can also be used when controlling other streamers in the house that source from the same music database on my NAS. I have some terabytes of music stored on my NAS.
Mpad is also more responsive than the webui of volumio/runeaudio.
I just recieved my ufl connection board for the bbb and am finishing the acko reclocker so there will be some aural improvements this christmas period
Than some pin 20 tweaking (have to desolder the board stack and that's holding me back a bit)
I think that my music source is than kind of finished.........
At least for the time being and untill the botic cape comes out
or I get bored......My amps are (in my humble opinion) of excellent reference quality so I am now concentrating on a new loudspeaker project.
It keeps the audio nut of the streets
Hi guys
Finally my dddac arrived, and have now been playing for 5 days. The dddac sounds more analog than my Buffalo III se. I think it's more emotional. The music grabs my attention more than before, and I must say this looks very promising.
But, can someone tell me if it is normal with audible noise from this exellent sounding
dddac.
I have 4 decks and the Cinemags on output. I have to turn up vol to hear it, but still...
I have also put caps on A,pos-B,pos and A,neg- B,neg, ( vishay mkp 1837. 15 nf )
Maybe it's normal with noise on a Nos design ?
Thx
Finally my dddac arrived, and have now been playing for 5 days. The dddac sounds more analog than my Buffalo III se. I think it's more emotional. The music grabs my attention more than before, and I must say this looks very promising.
But, can someone tell me if it is normal with audible noise from this exellent sounding
dddac.
I have 4 decks and the Cinemags on output. I have to turn up vol to hear it, but still...
I have also put caps on A,pos-B,pos and A,neg- B,neg, ( vishay mkp 1837. 15 nf )
Maybe it's normal with noise on a Nos design ?
Thx
No, mine is dead quiet, and so are others I've heard.
What kind of noise are you hearing, white noise, hum..?
Maybe start with taking the Cinemags out and putting the supplied output caps in.
At a given gain any noise floor will become audible.
Hi stijn001
It is white noise.
When I compare the dddac with Buffalo, the noise increase with higher vol on dddac, but not with Buffalo. The noise on Buffalo is very low, so low I have problem to hear it, had to ask my son to listen for me.
There where no supplied caps, so can not leave out the cinemags yet. Think I have to check out my cables and connections to start with.
It is white noise.
When I compare the dddac with Buffalo, the noise increase with higher vol on dddac, but not with Buffalo. The noise on Buffalo is very low, so low I have problem to hear it, had to ask my son to listen for me.
There where no supplied caps, so can not leave out the cinemags yet. Think I have to check out my cables and connections to start with.
which power supplies are you using and how are they wired?
Do you have any pictures?
And can you turn it up load and get us an audio or video recording of just the noise?
I am using the stock supplies James.
The Cinemags are wired brown-neg out, red-pos out. Yellow-hot ( xlr 2 ) orange-cold(xlr3)
I don't have access to equipment for measure the noise. And it's no more "noise" than what's normal from my turntable. Less I will say. You must listen close to the speaker to hear it.
Anyway, the dddac sounds great already and keeps getting better day by day.
The Cinemags are wired brown-neg out, red-pos out. Yellow-hot ( xlr 2 ) orange-cold(xlr3)
I don't have access to equipment for measure the noise. And it's no more "noise" than what's normal from my turntable. Less I will say. You must listen close to the speaker to hear it.
Anyway, the dddac sounds great already and keeps getting better day by day.
When I played with the Cinemags, I found they picked up a lot of noise, I never found the root cause.
Maybe the TP BIII has some HF filtering going on, which wouldn’t surprise me btw. ;-)
Also, the Sabre chip has a slightly lower noise floor then the PCM1794, 3 dB or so if I remember correctly. At full amplification (volume wide open), close to the speaker in a quiet room, there will always be some audible noise.
Pictures or a sound sample might tell us more..
that should be fine.
I always get a tiny background noise on mine, but it's only detectable if I turn up load and listen real close to the speakers.
How are you supplying signal to your dddac? WaveIO? If so, you need to make sure you haven't directly connected all 4 mounting screws if you have a metal chassis as 1 is a grounding point and you can create a ground loop.
Also, how far away is your dddac and cinemags from the mains transformer?
Thx James
Cinemags and main trafo's are far away from each other.
I have a question about the resistors in paralell with the cinemags. I am now using 15 kohm, but want some more gain. What do I do ? Go up to 20-22 kohm, or down to around 7.5-10 kohm ? ( have 2 more 15 kohm I can paralell, then it will be 7.5 kohm ? )
Will this change of resistor value have influence on the output impedance ? I understand it's important to keep the impedance as low as possible at output. Or am I wrong ?
Thx
Cinemags and main trafo's are far away from each other.
I have a question about the resistors in paralell with the cinemags. I am now using 15 kohm, but want some more gain. What do I do ? Go up to 20-22 kohm, or down to around 7.5-10 kohm ? ( have 2 more 15 kohm I can paralell, then it will be 7.5 kohm ? )
Will this change of resistor value have influence on the output impedance ? I understand it's important to keep the impedance as low as possible at output. Or am I wrong ?
Thx
They won't have any influence on the gain. You want to have about 15kohm in total, but bear in mind that this is an parallel with your amp/preamp stage, so measure that and work out what you need. 50k or 100k are typical values for preamps, so you may need increase a little to get 15k in total
Hmmm,,,not shure what you mean James.
There are two resistors, 15k on each channel. One leg on hot ( nr 2 on xlr ) and one on nr 3 (cold)
So if what you are saying is correct I have a total of 30k ? Or are we talking one channel ?
What do I do to increase a little to get 15k in total ?
Please have patience with an "old fart" who recently has discovered the fun of diy.
There are two resistors, 15k on each channel. One leg on hot ( nr 2 on xlr ) and one on nr 3 (cold)
So if what you are saying is correct I have a total of 30k ? Or are we talking one channel ?
What do I do to increase a little to get 15k in total ?
Please have patience with an "old fart" who recently has discovered the fun of diy.
no worries.What I mean is that yes you have it right, so that when nothing is plugged into your output, each one of your Cinemags see a 15k load across the outputs, which puts them in their happy place. All good so far.
But then you go and plug some cables between your XLR/RCA outs and connect the cinemag outputs to the input of your amp. Your amp input will also have a load, which is then connected in parallel with your 15k resistors.
You can get the load from your amp by looking at the spec sheet or just by measuring with your meter between the pos and neg of 1 of the inputs with nothing plugged in. A lot of amps seem to be either 50k or 100k.
Then you can use some maths or a calculator like this:
Parallel Resistor Calculator R1 + R2 = equivalent resistor R resistance circuit equiv total resistor finder made easy piggyback = parallel - sengpielaudio Sengpiel Berlin
To see what you end up with and have a play with the numbers to see what to aim for.
As an example, if your amp is 50k, then you need about 21k resistors to get a total of around 15k
I also found a lot of noise when using the Cinemags, tried all sorts of ways to solve the problem but I wasn't able to. I kept the Cinemags in for quite a few months and friends couldn't believe I was living with such a big background hum. I pulled them out last week and all is perfectly quiet.
I'm not using output caps , just running the signal straight to the rca's without any problems
One more thought. Presuming you are using a single-ended (RCA) output To increase gain you might want to try connected the POS/NEG terminals instead of POS/Common. There was a lot of discussion about this in this thread and didn't work well for everybody, but works well for me.
Besides, I would definitely try with a normal caps instead of the Cinemags, see if that improves your noise/gain issues.
It makes good technical sense. Great to read this from somebody getting along without a transformer. It is always a compromise
I think we need to be a bit careful here. there is absolutely no reason why the DDDac with or without Cinemags should hum if wired correctly.
It's all down to correct conections and earthing. There are a few traps for the unwary. I recently reported a hum, and found the cause was that earth connection from the Wave IO to earth, so when I moved to an earthed metal chassis Voila hum starts.
So I would just keep on checking things with or without Cinemags and be confident that there's no intrinsic reason for any hum
David