The nature of being a 1-bit DAC means software volume control will never work as one single bit of data only gives you a range of 6dB to adjusts software volume before you lose the whole bit of data. It is both non practical and detrimental to SQ if software volume is enabled, thus analog resistors ladder volume control is used. It is actually the correct thing to do not to have any software volume with a 1-bit DAC.Sure but software volume control doesn't work imagine needing to use the teeny volume key for each youtube video or tracks lol
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Cayin RU7: 1-Bit Resistor Network Dongle DAC /Amp
- Thread starter Andykong
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wipeyourbuttocks
New Head-Fier
Damn, thanks for the info. I have a question tho - why would software volume control work on other platforms like Android?The nature of being a 1-bit DAC means software volume control will never work as one single bit of data only gives you a range of 6dB to adjusts software volume before you lose the whole bit of data. It is both non practical and detrimental to SQ if software volume is enabled, thus analog resistors ladder volume control is used. It is actually the correct thing to do not to have any software volume with a 1-bit DAC.
Software volume control only works in non-exclusive USB mode. Witch means, you're listening to your phone DAC, RU7 would act like an external amp in that configuration.Damn, thanks for the info. I have a question tho - why would software volume control work on other platforms like Android?
There are several common ways to implement volume control in USB audio devices. The first is to do it on the source devices' audio core by reducing the digital bit-depth of the raw PCM audio data (again, every bit gives you 6dB of range). This is generally considered the worst of the choices because you are basically trading data bits / fidelity for loudness control. The lower the volume goes, the more bit of the original music you will lose. For typical 16bit music, you might end up getting just 12~14bit or less. This is the reason why it is always recommended not to use the source digital volume if you can. The next, and probably the more mainstream way of how digital volume control is done these days is to use the gain control function built into most DAC chips. DAC chips these days usually have an internal 24-bit upsampler or something similar to put into more empty bits that give them greater control of digital bits for volume control. So even by reducing a few bits for volume control, you will be losing most of those empty bits that don't affect SQ. To make sure the source will use the DAC internal volume control instead of the source's volume control, there is a control function built into the USB receiver chip that, when connecting the USB audio device to the source, that chip on the USB audio device will tell the source device what is the preferred method the USB audio device wants the source to control volume (*whether to let the USB audio device handles the volume control or not). In the case of RU7, Windows will be smart enough to listen to the USB receiver chip on RU7 to disable its software volume control. On Android, however, that part of the function is left out because Andoird left out a lot of functions when it was slimmed down from Linux. It can still be done but is more convoluted. Also, some users find it more convenient to use digital volume control even if it is going to harm SQ, so some manufacturers just leave the option open for user to determine how to use it.Damn, thanks for the info. I have a question tho - why would software volume control work on other platforms like Android?
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Software volume control only works in non-exclusive USB mode. Witch means, you're listening to your phone DAC, RU7 would act like an external amp in that configuration.
RU7 can only function as DAC/Amp. In the case of mobile phones, most of them don't have a DAC built-in, the CPU and associated chipsets will act like a highly integrated solution at the chipset level, including DDC (digital to digital conversion) that facilitates format transcoding and volume control (at digital domain).
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Anyone has RU 7 and one of these dongles and can compare them please: iBasso DN Elite and Hiby FC6?
Thank you
Thank you
Totally enjoying my RU7. Except for one issue. For some strange reason once my iphone 14 pro max battery hits 70% and below the RU7 seems to stop working? I mean it still lights up. I can still toggle the menu, even adjust the volume, but no music/audio/sound comes out of the IEM. I have tried unplugginge and plugging it back. Tried different IEMs snd still the same issue. Once I charge up my iphone then everything goes back to normal operation. I cant digure out if its an iphone issue or its the dongle. Anyone experienced this? Thank u
captblaze
Headphoneus Supremus
As a battery drains its operating voltage decreases. I would venture to guess that at 70% the battery cannot provide adequate voltageTotally enjoying my RU7. Except for one issue. For some strange reason once my iphone 14 pro max battery hits 70% and below the RU7 seems to stop working? I mean it still lights up. I can still toggle the menu, even adjust the volume, but no music/audio/sound comes out of the IEM. I have tried unplugginge and plugging it back. Tried different IEMs snd still the same issue. Once I charge up my iphone then everything goes back to normal operation. I cant digure out if its an iphone issue or its the dongle. Anyone experienced this? Thank u
Dang. Never experienced this with my Questyle M15. Guess I might be too hard on my iPhone what will all the listening and charging. And its not even 2 years old. Time to upgrade to the 16 when it comes outAs a battery drains its operating voltage decreases. I would venture to guess that at 70% the battery cannot provide adequate voltage

captblaze
Headphoneus Supremus
My solution is a Mag safe battery. Helps avoid extra wires, but keeps feeding the phone's battery while the DAC is connectedDang. Never experienced this with my Questyle M15. Guess I might be too hard on my iPhone what will all the listening and charging. And its not even 2 years old. Time to upgrade to the 16 when it comes outThank u
yup, when I'm using my RU7 at the office, it lives on a MagSafe. I love the RU7, but it is so power hungryMy solution is a Mag safe battery. Helps avoid extra wires, but keeps feeding the phone's battery while the DAC is connected
Kroppand
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Once I felt pretty stupidTotally enjoying my RU7. Except for one issue. For some strange reason once my iphone 14 pro max battery hits 70% and below the RU7 seems to stop working? I mean it still lights up. I can still toggle the menu, even adjust the volume, but no music/audio/sound comes out of the IEM. I have tried unplugginge and plugging it back. Tried different IEMs snd still the same issue. Once I charge up my iphone then everything goes back to normal operation. I cant digure out if its an iphone issue or its the dongle. Anyone experienced this? Thank u

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Once I felt pretty stupidI completely reduced volume on the iphone to 0and RU7 “stopped” producing sound in IEMs but I didn’t correlate with my action. It requires to have at least some level volume up in iphone. Check it, especially shortcuts if you use them, e.g. “turn off volume when battery≤70%”.
“turn off volume when battery≤70%”
This is a strange battery-saving setup. Never heard about this before.
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Kroppand
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Indeed, just hypothesis for troubleshooting“turn off volume when battery≤70%”
This is a strange battery-saving setup. Never heard about this before.
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Totally enjoying my RU7. Except for one issue. For some strange reason once my iphone 14 pro max battery hits 70% and below the RU7 seems to stop working? I mean it still lights up. I can still toggle the menu, even adjust the volume, but no music/audio/sound comes out of the IEM. I have tried unplugginge and plugging it back. Tried different IEMs snd still the same issue. Once I charge up my iphone then everything goes back to normal operation. I cant digure out if its an iphone issue or its the dongle. Anyone experienced this? Thank u
I think there is a problem with your phone. My iPhone 14 Pro Max everything works fine down to even 10% battery
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