You need to look at the DC imbalace at the TVC input, not AC.
0.1 VDC would be a bit too much.
0.1 VDC would be a bit too much.
so I need to measure dc between pin 2 and 3 on XLR outputs from dac?
funny thing is thats it worked fine for years and suddenly this **** occurred, but the dac is on 24/7/365 so I guess a component could start to malfunction
btw if dc on output is problem, then I guess 4 (dc blocking)caps in series with pos and neg on both channels would give me the answer?
easy to solder in between male and female xlr cable connectors
funny thing is thats it worked fine for years and suddenly this **** occurred, but the dac is on 24/7/365 so I guess a component could start to malfunction
btw if dc on output is problem, then I guess 4 (dc blocking)caps in series with pos and neg on both channels would give me the answer?
easy to solder in between male and female xlr cable connectors
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now I´ve measured between pin 1 and 2 + 1 and 3 and have 2,7vdc between both phases in both channels
then I soldered and XLR jumper with 2,2µF in series with signal on pin 2 and 3 and no dc gets through, but it sounds the same?!?
have a knowledgable friend here and he´s as confused as I am
DD! any idea?
then I soldered and XLR jumper with 2,2µF in series with signal on pin 2 and 3 and no dc gets through, but it sounds the same?!?
have a knowledgable friend here and he´s as confused as I am
DD! any idea?
If your transformer is not super sensitive, this should be fine.
I don't know where else to look for your problem.
I don't know where else to look for your problem.
fair enough....
however hope DD comes back here:
I think he uses 2 dac chips per channel to make them work as NONOVERSAMPLING dacs
I thought, what if one in a pair went down or out of service, could that cause a problem like this?
It sounds as if all below a certain frequency is really distant, even though I cannot proove it by mere ac measurements......
however hope DD comes back here:
I think he uses 2 dac chips per channel to make them work as NONOVERSAMPLING dacs
I thought, what if one in a pair went down or out of service, could that cause a problem like this?
It sounds as if all below a certain frequency is really distant, even though I cannot proove it by mere ac measurements......
No, I am not using two chips per channel. One chip per channel and each chip has two DACs inside (POS and NEG) for balanced output
Hi Leif, This is the first time something like this occurs. And suddenly it becomes clear, that to build stuff and maintain it, it is ok to have basic T&M equipment. But not when things are getting complex and fuzzy
Now with your problem, it clearly need deeper diagnoses. Like with my AP, I can do a frequency sweep with I2S output, so I go directly from digital to analog output. Mainboard in - Dac Out , graph on display from 10Hz to 22kHz
With a high bandwidth oscilloscope I can test exactly the signal shapes and timing of the I2s Signals and the analog output signal
Based on this it will become quickly clear what the problem is. Unless you have stuff like this and lack deep understanding of how the DAC is supposed to work at signal level, it is trial and error to get it back to work properly.
so my offer to you is to send the Mainboard+Dac Modules to me and I can do the diagnoses for you ? If needed repair too...
btw is the S/pdif input converted to I2S too on MB?...because the fault seems to be when dac is fed from Studer A727 digital output too...
I promised my self already years ago, that no one should suffer a defective DDDAC and I would always help 🙂
I have repaired a few in past years so we have 100% happy users 😀
I don´t know how many of the 1543 I built, but it was quite a few and I´ve recommended the 1794 to quite a few based on my own experience
no complaints so far...
no complaints so far...
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We have almost the same speakers. Very rare to see, so I just had to comment on that. I drove down to Hans when I was living in Copenhagen and got them maybe in 2008. I have such good memories from that trip, hanging out with Hans, Cees Pel and the guys at Audio Life 🙂
Mine are made of tonewood and PHY-HP drivers, not EMS.
Nice!
Cees and Hans are long time friends of mine. The cabinet design has a long history of development that I have followed all that time. Unfortunately Hans has passed away a few years ago form Cancer. The cabinets he made for me are made to my specifications and Cees and I have tuned them with bracing in my set. These are the last cabinets Hans has made and are very dear to me.
I use a Phy tweeter, the same you will have in your km30.