[brjoon1021]

Check AliExpress I bought the DC04 Pro from them for 85 US

 

[laleeee]

What would be a dead neutral source at the same price bracket?

DC04PRO

 

[brjoon1021]

I thank you for two reasons, the first is the words of praise you spent on me and the second is because you were one of the few to believe that with a minimal expense you could achieve what is evident to both me and you.. that is, a clear improvement in the performance of the dongle as well as the convenience of no longer having to worry about the "usual dead phone". Thank you for sharing your experience... I was sure that you would like it and that you would do what I also did... share something for the benefit of everyone without having any personal gain. This is the highest purpose that a forum like this can achieve. Ensuring that users who have the same passion share it and share the small and large discoveries that can be made through that passion. Thanks again.

I'm curious. Are we sure that the phone isn't powering the dongle ? Didn't another member show that if you unplug the brick it still works (not at home to try anything) ? There are 2 possible power sources for the dongle via the hub: the phone and the brick. I'm wondering if there is a way to arrange it so that there is no chance that the phone is passing power and data to the hub (defeating the purpose) ?
I wish that there wasn't an attached cable to the hub I wish it was just a naked hub then a data only cable (haven't determined whether there is such a thing there are power/charging only cables) could be connected from the phone ensuring it's only supplying clean data. Or the cable coming from the hub could be split open and the power line, usually the red one, cut.

 

[Polky74]

Don't worry... to answer someone who didn't believe it, the cable to the streamer has already been measured by a forum user and no current passes through that cable.

I conducted some tests and performed some measurements using a simple USB voltmeter.

Below you see the output voltage from a USB cable connected to a powerbank:


Below you see the same cable as before powering the USB hub (blue light on):


Below you see the 'data cable' of the USB hub (the one I would connect to the smartphone):


As you can see, the USB voltmeter doesn't even turn on, that is, it doesn't receive power (while at the same time the USB hub is still turned on and powered by the power bank).

From a circuit point of view, it is quite simple to implement
a circuitry to achieve this result.

It is sufficient to insert the equivalent of a diode in series with the wire containing the positive pole in the data cable (the one that connects to the smartphone), placing the anode (of the diode) towards the USBC connector to connect to the smartphone.

This prevents power from the USB hub from flowing to your smartphone.

The smartphone is still able to send the digital signal
(contain the data) to the USB hub, and, potentially, also its power supply, which would conflict with that of the hub.
This is prevented by specific circuitry (what I earlier called 'diode equivalent').

So, from a superficial analysis, I don't see any conceptual impediments to the functioning of this HUB.

 

[TheFritz]

I'm curious. Are we sure that the phone isn't powering the dongle ? Didn't another member show that if you unplug the brick it still works (not at home to try anything) ? There are 2 possible power sources for the dongle via the hub: the phone and the brick. I'm wondering if there is a way to arrange it so that there is no chance that the phone is passing power and data to the hub (defeating the purpose) ?
I wish that there wasn't an attached cable to the hub I wish it was just a naked hub then a data only cable (haven't determined whether there is such a thing there are power/charging only cables) could be connected from the phone ensuring it's only supplying clean data. Or the cable coming from the hub could be split open and the power line, usually the red one, cut.

Of course you can simply measure it. I use this hub/power bank combo on an old iPhoneSE for streaming only with DAC-Amps that require to much power to work on iPhones.
When the power bank is not connected to the hub and there is NO DAC attached, the current drawn from the phone is in the order of 0.01A to feed the hub electronics. If you attach your DAC and externally power the hub before connecting it to the phone, the current drawn is the same (i.e. only current for hub-detection etc.). See image below (ignore the additional wires connected to the hub - not used here).

If you then unplug the power bank, the phone (tries to) power the DAC with a current draw of about 0.14 A
(which then directly fails for this specific power hungry DAC).

Thus I guess we can conclude: yes the DACs are powered from the external source, the phone only feeds the hub electronics, not the attached devices. And now you can use power hungry devices (including all those Lightning-iPhones don't like due to excessive power consumption) and also provide clean power. It obviously also works with USB-C hosts (Android, iPad-Mini) and more modern iPhones (12 Mini).
P.S.: The ddHifi-adapter is a Lightning-to-C adapter which can additionally power the iPhone if required - but not the hub/the attached devices).

Edit: I see the previous measurements cited above confirm this. To give you an idea what dongles can be used this way, an additional picture of my random mess...

 

[Polky74]

@TheFritz Have you noticed improvements from an audio point of view when using the mod? If so which ones? It's important to share what we think about these installations with others. Thank you.

 

[eloelo]

I present a mod for any dongle that can pull out its true soul, and to the smartphone not to wear out the battery. The mod in question was designed, made and refined by giuca70 an Italian friend of mine also present here on Headfi. The pieces for the realization are two which can be reached an optional third.
The first is a type c usb hub that allows the dongle’s exclusive power supply and physically separates the current from the data.
The second is a large capacity power bank and the third is an RJ45 type C network adapter.
The purpose of this mod is to prevent the charging of the smartphone during its use as a streamer, power the dongle in a powerful and clean (power-bank), physically divide the current from the data (usb hub) and do not use wifi to download music through streamer (usb rj45). Here is a photo that explains how to connect the whole, below the three pieces needed.




These are the three pieces you need to make it:

USB HUB

https://www.amazon.it/dp/B0C2YN8F7Z

Power-bank

https://www.amazon.it/dp/B07YPS5JC5

RJ45 USB TYPE C

https://www.amazon.it/gp/product/B07M8GSLQB/

I saw your post and was curious about applying the same to my setup

but instead of dongle, it is a usb dac (SMSL SU1)
instead of phone as source, it is a desktop pc
instead of power bank, I used the wall socket
instead of usb hub, I used a usb isolator that allowed power input
instead of iems, its active speakers

I was wondering if I could exclude the power supply from the PC, so I cut open the usb cable and cut the red wire that is used for power input. The power supply now only comes from the wall socket, so turning off the socket causes the dac to stop working. The difference in sound turned out to be pretty positive so far. Extra note: My desktop has a history of having finnicky usb slots (not able to recognize devices or just disconnecting randomly). I will continue with this setup and see if any placebo disappears over the next few days lol.

 

[TheFritz]

@TheFritz Have you noticed improvements from an audio point of view when using the mod? If so which ones? It's important to share what we think about these installations with others. Thank you.

Well the biggest improvement is that some of these DAC/Amps run at all in such a "mobile" setup on some hosts (including these simple old iPhones with bitperfect output for Qobuz/Apple Music HighRes Lossless).
Concerning the sound, I have to explain a bit: In the past few months I experimented a lot with power supplies for desk an mobile use. Not by buying some fancy snake-oil cables or expensive filters... but I started to include e.g. battery powered super conductors in the power supply of some devices - including mobile amps/DACs. So, yes I do hear an improvement from clean and "quickly available" power.
In this specific setup, I get much darker background and better dynamics from the battery power on those (older) DAC-dongles that do not have very sophisticated power management/isolation. On the others, more modern ones like M15, RU6 and RU7 I get at least rid of most of the RFI interference from WiFi. So for me it is an obvious improvement (and very cheap by the way).

 

[brjoon1021]

Of course you can simply measure it. I use this hub/power bank combo on an old iPhoneSE for streaming only with DAC-Amps that require to much power to work on iPhones.
When the power bank is not connected to the hub and there is NO DAC attached, the current drawn from the phone is in the order of 0.01A to feed the hub electronics. If you attach your DAC and externally power the hub before connecting it to the phone, the current drawn is the same (i.e. only current for hub-detection etc.). See image below (ignore the additional wires connected to the hub - not used here).

If you then unplug the power bank, the phone (tries to) power the DAC with a current draw of about 0.14 A
(which then directly fails for this specific power hungry DAC).


Thus I guess we can conclude: yes the DACs are powered from the external source, the phone only feeds the hub electronics, not the attached devices. And now you can use power hungry devices (including all those Lightning-iPhones don't like due to excessive power consumption) and also provide clean power. It obviously also works with USB-C hosts (Android, iPad-Mini) and more modern iPhones (12 Mini).
P.S.: The ddHifi-adapter is a Lightning-to-C adapter which can additionally power the iPhone if required - but not the hub/the attached devices).

Edit: I see the previous measurements cited above confirm this. To give you an idea what dongles can be used this way, an additional picture of my random mess...

Thank you for the clarifications, everyone.

You have a few dongles . Which ones do you think are the best, for lack of a more focused question?
I want to have a handful or perhaps two handfuls to use in my home stereo using the brick hub method You just responded to. So far I really like my DacPortHD , RU6, RU7 FC6, ovidious B1, mojo 2 and iBasso DC04.

Pretty broad selection of characters and palletes and technologies there. But, like a TV shopping network shopper I'm never quite satisfied and always ready to pull the trigger on more...

Any particular recommendations?

noticed you have a groove I've always considered that one It would be going straight into a tube preamp that's 50 ohms so maybe I would not suffer that issue due to its high output impedance?

Of course, I'm not looking for a new bottom of the pile of what I already have be looking for a new middle of the pack end up or even best.

 

[Polky74]

@brjoon1021

Considering those you have and those you lack, if I were you I would go shopping at Hifigo...

Questyle M15 (type C version) $ 249

https://hifigo.com/products/qustyle-m15?variant=42703330410735

and

Shanling UA3 $ 109

https://hifigo.com/products/shanling-ua3-usb-dac-amp?variant=43711714689263


For just over 350 dollars (shipping and taxes paid) you get two stellar dongles... the Questyle M15 with its CMA current mode amplification (the only dongle to have it) and the Shanling UA3 with double AKM 4493SEQ chip, with the legendary "Velvet Sound" tone typical of the best Shanling DAP models.

 

[TheFritz]

Thank you for the clarifications, everyone.

You have a few dongles . Which ones do you think are the best, for lack of a more focused question?
I want to have a handful or perhaps two handfuls to use in my home stereo using the brick hub method You just responded to. So far I really like my DacPortHD , RU6, RU7 FC6, ovidious B1, mojo 2 and iBasso DC04.

Pretty broad selection of characters and palletes and technologies there. But, like a TV shopping network shopper I'm never quite satisfied and always ready to pull the trigger on more...

Any particular recommendations?

noticed you have a groove I've always considered that one It would be going straight into a tube preamp that's 50 ohms so maybe I would not suffer that issue due to its high output impedance?

Of course, I'm not looking for a new bottom of the pile of what I already have be looking for a new middle of the pack end up or even best.

Well - it depends on what you use it for. I am more a headphone guy and use IEMs only on the go/travel so I am a bit more into more powerful DAC/Amps. I am not so much using them as DACs for other amps. Besides some of the dongles you mentioned already, I personally love the questyle M15 - especially for planars (headphones and IEMs) with its specific current mode amplification modules. But also really great for a wide range of dynamic headphones and IEMs ... but my praise may result from a new-toy-syndrome. You may however want to wait for the questyle CMA18...
Since you included battery powered portable DACAmps, I also love my mojo2 and the (not longer available EDIT: just looked it up, seems to be still available at some shops) Monolith THX portable as DACamps. As powerful Bluetooth devices (bricks), I enjoy the Topping G5 a lot and sometimes the Xduoo xd05-Bal (EDIT: ... which can be switched to external power supply).
The apogee groove is a bit special indeed - I use(d) it only for high-impedance headphones (HD6xx, DT1990pro, etc). I think its output impedance is near 20 Ohm. I think I would not buy it again today since there are much cleaner (battery powered) alternatives for headphone use but it might be well-suited as DAC for a tube (pre)amp.

 

[brjoon1021]

Everyone who has the M15 seems to like it really well. I only, and can only, use the 3.5mm out as I'm going into an unbalanced RCA tube preamp and all my use is 100% home stereo like next to my record player, home stereo....
I've heard that the M12 and m15 are different but similar I could save a hundred bucks by getting the 12 unless it's lesser... Someone responded that it's different maybe grainier but not lesser. questyle themselves responded to me that they're the same through the 3.5 out but they cited numbers - that weren't the same - for output to show me that they are the same

 

[Polky74]

Everyone who has the M15 seems to like it really well. I only, and can only, use the 3.5mm out as I'm going into an unbalanced RCA tube preamp and all my use is 100% home stereo like next to my record player, home stereo....
I've heard that the M12 and m15 are different but similar I could save a hundred bucks by getting the 12 unless it's lesser... Someone responded that it's different maybe grainier but not lesser. questyle themselves responded to me that they're the same through the 3.5 out but they cited numbers - that weren't the same - for output to show me that they are the same

Aside from the different expense ($100) the real difference between the two... as I see it, is that one looks at your present (M12) while the other is ready for your future (M15). In addition to this, if you also sometimes use IEMs the difference is there and it is enormous (4.4mm balanced). By the way, just this evening I placed a pre-order for the Hidizs mp145 planar IEMs which many say are truly unique... well with these I think the difference is clear.

 

[TheFritz]

Everyone who has the M15 seems to like it really well. I only, and can only, use the 3.5mm out as I'm going into an unbalanced RCA tube preamp and all my use is 100% home stereo like next to my record player, home stereo....
I've heard that the M12 and m15 are different but similar I could save a hundred bucks by getting the 12 unless it's lesser... Someone responded that it's different maybe grainier but not lesser. questyle themselves responded to me that they're the same through the 3.5 out but they cited numbers - that weren't the same - for output to show me that they are the same

Well I never heard the M12 and as far as I understand it, it is actually really more or less "half" the M15 with similiar tech and just one CMA module for SE only. But one of the differences might play a role in your setup; the M12 has automatic impedance detection and gain setting (M15 has a manual switch). In your case, the connected (pre-)amp would automatically switch it to 2V rms Line-Out mode. Might be beneficial for you.
Nevertheless, I always buy this stuff to keep it for longer (as you may have noticed) and I personally would think about possible future use as portable balanced DACAmp and/or for 4.4mm-to-2XLR balanced Line-Out use and grab the M15. I hope someone here has both the M12 and M15 and can give you a more valid answer...

 

[Warfront1]

Partially on topic, as it is being recommended as one of the best...
Does anyone have any ideas on how to troubleshoot a brand new TANCHJIM SPACE not working?
I tried my Android phone (LGV20), an iPhone 15, X670E Motherboard over a USB 3.2 Gen 2x2 port, and a SAMSUNG Galaxy Tab S6 Lite.
On Windows I was trying just through control panel with the "Test" button and also on general system audio.
On the Android devices I tried with USB Audio Player PRO and also Neutron.
On the iPhone 15 I just tried it on Pandora.
Every device I plug it into acts as if it is working and actively outputting to the TANCHJIM SPACE.
The TANCHJIM SPACE even flashes it's blue light on to acknowledge that it is on and connected.
The problem is I can't get it to output anything from any source device.

I did see an Amazon review where someone complains that his volume button broke with light usage.
I'm hoping I just overlooked something simple.

Thanks,
wafront1