Hi All,
I have an issue with my DAC, every time that I switch tracks or inputs there is a noise for a second, the noise doesn't appear during playback, when when I switch tracks.
I believe it's related to some kind of mute "mechanism", I can see relays on the pcb that clicks when there is a signal lock.
Any idea or suggestions?
Thanks
I have an issue with my DAC, every time that I switch tracks or inputs there is a noise for a second, the noise doesn't appear during playback, when when I switch tracks.
I believe it's related to some kind of mute "mechanism", I can see relays on the pcb that clicks when there is a signal lock.
Any idea or suggestions?
Thanks
Which DAC are we looking at? Many will omit mute circuits for "Audiophile performance". Some DACs will emit noise when manually selecting tracks but not when tracks change during normal playback software.
Then there are others which emit noise when switching between DSD and PCM, or even when the sample rates change during PCM.
Some DACs use relays for this function and you can hear them click. Some of them are not terminated properly and you will hear the click through your speakers, which is lazy and stupid design.
Then there are others which emit noise when switching between DSD and PCM, or even when the sample rates change during PCM.
Some DACs use relays for this function and you can hear them click. Some of them are not terminated properly and you will hear the click through your speakers, which is lazy and stupid design.
With no sight of your schematic, I would look to see if there is a non functioning mute circuit as all DACs when looking for signal do weird things, noise wise, that is why there should always be a mute system. Mainly a pair of DTC transistors on the output line.
the dac on my phone goes high impedance when not playing anything,causing noise or buzz,that's maybe what's happening with yours
This is exactly what happens.
It also happens when I switch between inputs.
The DAC is Maverick Audio Tubemagic D1,can't find schematics for it anywhere, no response from Maverick Audio.
The dac chip is said to be AD1955: https://www.analog.com/media/en/technical-documentation/data-sheets/AD1955.pdf
If you search through the data sheet for the word "mute," you can see how it can be muted under different conditions.
Most USB interfaces have a MUTE signal output which can be used to mute the dac chip at appropriate times that the USB interface knows about. The USB interface chip used by the dac is: https://www.macnica.com.tw/sites/default/files/documents/downloads/TE7022SL_PB-v21.pdf ...it is a very old fashioned USB 1 interface with a maximum sample rate of 16/48. Searching through the manual does not find the word 'mute,' which is not encouraging.
It kind of looks like it might take some redesign of the dac to fix the problem. No wonder the manufacturer doesn't want to reply to you.
If you search through the data sheet for the word "mute," you can see how it can be muted under different conditions.
Most USB interfaces have a MUTE signal output which can be used to mute the dac chip at appropriate times that the USB interface knows about. The USB interface chip used by the dac is: https://www.macnica.com.tw/sites/default/files/documents/downloads/TE7022SL_PB-v21.pdf ...it is a very old fashioned USB 1 interface with a maximum sample rate of 16/48. Searching through the manual does not find the word 'mute,' which is not encouraging.
It kind of looks like it might take some redesign of the dac to fix the problem. No wonder the manufacturer doesn't want to reply to you.
AD1955 dac chip is in the Tubemagic D2, my dac is the D1 and the dac chip is unknown.
TubeMagic DAC Product Comparison Sheet
BTW this noise doesn't appear to happen when using the USB input, only when using the optical and coaxial inputs.
TubeMagic DAC Product Comparison Sheet
BTW this noise doesn't appear to happen when using the USB input, only when using the optical and coaxial inputs.
Thank you. Looks like part numbers have been intentionally removed on some or all of the chips in order to discourage reverse engineering attempts. That would seem to make the problem much more complicated to track down. Only thing that comes to mind is to start reverse engineering it anyway, while troubleshooting it at the same time. Likely a whole lot of work with no guarantee of success. IMHO, if the problem is too annoying then makes most sense to replace the dac with a better one. That or switch to using it with USB.
I don't know why they went to the trouble of scraping off the part numbers in such a poorly performing device, seems the time would have been better spent on optimising performance and fixing bugs but no.
Anyway, here you go for chip info:
Maverick Audio TubeMagic D1 Plus DAC TE7022 Coaxial / Optical / USB - Audiophonics
The Crystal 4398, if used, is the one under the wires (prolly) and hidden from view. The older models I have no idea about but I guess someone will pop along and tell us what it was, if indeed it is the older version. The USB receiver is the horrific TE7022, with missing samplerates. That's pretty obviously the chip next to the USB connector.
I can tell you for a fact that this implementation would be missing tons of kit required to actually function properly, such as the mute circuit, and the filtering would also be highly suspect. They leaned a lot on the tube output, did Maverick. I've seen plenty of terrible digital designs, and not all originated in China - though most did. They use datasheets and an autorouter, which leads to nominally terrible performance.
Anyway, here you go for chip info:
Maverick Audio TubeMagic D1 Plus DAC TE7022 Coaxial / Optical / USB - Audiophonics
The Crystal 4398, if used, is the one under the wires (prolly) and hidden from view. The older models I have no idea about but I guess someone will pop along and tell us what it was, if indeed it is the older version. The USB receiver is the horrific TE7022, with missing samplerates. That's pretty obviously the chip next to the USB connector.
I can tell you for a fact that this implementation would be missing tons of kit required to actually function properly, such as the mute circuit, and the filtering would also be highly suspect. They leaned a lot on the tube output, did Maverick. I've seen plenty of terrible digital designs, and not all originated in China - though most did. They use datasheets and an autorouter, which leads to nominally terrible performance.
This same noise issue seems to appear with my Orelle DA-180 (AD1865 Dac chip) as well and every time that I'm changing tracks there is this noise and then a 2-3 seconds of silence until I can hear the relay clicks so I'm missing 2-3 sec of music.
What is the source device for the SPDIF and or TOSLINK interfaces you use? Since you are not using USB, presumably its not a computer?
CD player and streamers.
It happens with every source that I've tried, it doesn't happen with 2 other DACs that I have.
It happens with every source that I've tried, it doesn't happen with 2 other DACs that I have.
....and it doesn't happen when the source is a PC connected to the DACs optical and coaxial inputs using a USB to toslink/spdif converter.
What happens while a track is playing if you quickly unplug then re-plug a coax or optical input? Does that make the same noise?
Yes, when I unplug it there is a noise and relay click, when plug it back in no noise, just relay click .
Okay. Looks like the noise happens when there is a short drop out in the data stream. It would be nice to confirm that with a scope when switching between tracks. Maybe the mute mechanism with the relay isn't fast enough to keep up with it.
I'm sure it's related to "the mute mechanism with the relay isn't fast enough to keep up with it" but unfortunately I don't have a scope to trace the source of the problem and was hoping that someone can give me an idea what can be the cause? any passive component or transitor?
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