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?
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...
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
Hi Johan,
You are welcome to visit for a listening test with your dac. Send me pm if you like.
My set is all self build with quality components. Does this mean megabucks setup? I do not think so, there are many much more expensive amplifiers and loudspeakers out there. But I do dare to challange anyone with such a megabucks setup to compare with my humble diy stuff
The amps are build from directly heated triode tubes, interstage coupled. The loudspeakers are an open baffle system with a very nice field coil unit from EMS France, almost full range, with a Phy tweeter on top running from 15khz. This is a VERY revealing system. It resides in a living room without special room treatment.
But that does not mean that a better clock on less revealing systems are not a welcome improvement. After all your system is a strong as your weakest link.
Regards,
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.
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.