GUSTARD DAC-R26 Balanced Decoder R2R+1Bit Dual Native Decoding Music Bridge

[rodthebod]

Cheers. I'm still tinkering here with the lid off - and it unplugged. Will try a little later this evening NZ time...

Incidentally, assuming the shielding of the internal connector cable is Ok, one could just cap across the external terminal with the aerial unscrewed. Less finicky as the scale is easier.

If I read you correctly, It's the antenna cable itself that's causing the degradation of sound issue by radiating RF inside the sensitive components inside the R26. If the antenna cable is removed as you show on your photo then the issue is solved and the external antenna chassis socket is completely redundant, capping it would be only a cosmetic improvement. Or have I misunderstood?

 

[Neslo1108]

I have installed 1.42 firmware (using Balena) and I am now trying to install the M2.1 firmware (March 2023) via the exe program taken from the link on p1.
However even though my win pc can see the R26 as d drive when connected to the usb-c on R26 then the program can't see any usb drive.
Any clues to what I can try to make the M2.1 firmware (March 2023) program to see the R26?

 

[Jake2]

If I read you correctly, It's the antenna cable itself that's causing the degradation of sound issue by radiating RF inside the sensitive components inside the R26. If the antenna cable is removed as you show on your photo then the issue is solved and the external antenna chassis socket is completely redundant, capping it would be only a cosmetic improvement. Or have I misunderstood?

I meant the opposite to be honest - if the conductor is 100% enclosed in grounded shielding from the board out through the case to the aerial then it should only emit RF on the exterior of the case from aerial or exposed conductor if the aerial is removed. Whereas if the internal connector cable is removed the exposed conductor/RF emitting point moves to the inside of the case, a tiny aerial if you will.

So what I was thinking is leave the internal connector in place but remove the external aerial and cap across the aerial socket so there is no emission point on the exterior either.

Best case of course would be able to turn the BT emitter off in firmware. Actually, just occurred to me, I have an RF meter than works in the BT and wifi Ghz spectrum... I'll test emissions in various scenarios., BT selected, not selected, capped, internal connector etc etc

 

[rodthebod]

I have installed 1.42 firmware (using Balena) and I am now trying to install the M2.1 firmware (March 2023) via the exe program taken from the link on p1.
However even though my win pc can see the R26 as d drive when connected to the usb-c on R26 then the program can't see any usb drive.
Any clues to what I can try to make the M2.1 firmware (March 2023) program to see the R26?

I believe from memory that once connected and seeing your 'd'drive' you have to then switch on the R26 from the rear IEC socket to initiate the firmware download...... could be wrong, I use a Mac but tried using virtual PC software.

 

[Neslo1108]

I believe from memory that once connected and seeing your 'd'drive' you have to then switch on the R26 from the rear IEC socket to initiate the firmware download...... could be wrong, I use a Mac but tried using virtual PC software.

Thanks for sharing.
Hmm according to the limited description when opening the exe file then I shall switch off on the back and the program shall be able to see the USB on one of the ports in the sw.
I have tried to turn on the R26 with program open and PC connected and USB did not pop up as an option in the program...

 

[Clivem2]

All I can say is that my computer refuses to download the zipfile from mediafire. It's also blocked extra downloads....

At last I have the file...I'll give it a go.

 

[Clivem2]

Thanks for sharing.
Hmm according to the limited description when opening the exe file then I shall switch off on the back and the program shall be able to see the USB on one of the ports in the sw.
I have tried to turn on the R26 with program open and PC connected and USB did not pop up as an option in the program...

I’ve now completed the update. With the power switch off on the back of the R26 you wait for the USB to show, it took several seconds for me…I could also see many ports listed in the drop down menu. It says you might need to manually select the port.

I then turned on the power and clicked the top left button. It’s a bit messy but it’s worked for me.

Hopefully you’re using the USB-C port on the R26.

 

[Neslo1108]

I’ve now completed the update. With the power switch off on the back of the R26 you wait for the USB to show, it took several seconds for me…I could also see many ports listed in the drop down menu. It says you might need to manually select the port.

I then turned on the power and clicked the top left button. It’s a bit messy but it’s worked for me.

Hopefully you’re using the USB-C port on the R26.

Hi

I have now tried a different pc than the one I used to install fw 1.42 which worked back then and the other pc can see the R26 and the display fw is now updated to m2.1. strange but now I know that for the next update

 

[Stellabagpuss]

I meant the opposite to be honest - if the conductor is 100% enclosed in grounded shielding from the board out through the case to the aerial then it should only emit RF on the exterior of the case from aerial or exposed conductor if the aerial is removed. Whereas if the internal connector cable is removed the exposed conductor/RF emitting point moves to the inside of the case, a tiny aerial if you will.

So what I was thinking is leave the internal connector in place but remove the external aerial and cap across the aerial socket so there is no emission point on the exterior either.

Best case of course would be able to turn the BT emitter off in firmware. Actually, just occurred to me, I have an RF meter than works in the BT and wifi Ghz spectrum... I'll test emissions in various scenarios., BT selected, not selected, capped, internal connector etc etc

Excellent Jake, will be interesting to see if the BT socket is in use only when BT selected, or if its permanently on?
l guess the best solution if you need to keep BT,is to add additional sheilding to Coax, and get a longer cable and get the BT out of the box.

l now have my set up back up and running, so l can comment on my internal shielding mods on the R26, which l did 4 months ago, l got some catching up to do

 

[Jake2]

Excellent Jake, will be interesting to see if the BT socket is in use only when BT selected, or if its permanently on?
l guess the best solution if you need to keep BT,is to add additional sheilding to Coax, and get a longer cable and get the BT out of the box.

l now have my set up back up and running, so l can comment on my internal shielding mods on the R26, which l did 4 months ago, l got some catching up to do

Hi, quick answer for now (work to do) is after a fair bit of testing in multiple locations over the R26 internals and back plate / connector area with a 3-axis RF meter it appears the BT transmitter is only on when the BT is selected as an input. There's a 4-6x increase in RF readings in the range my meter covers (50Mhz - 3.5hgz) with BT selected over baseline RF levels with other inputs selected. That's with my early model R26 from Aug last year with original firmware still (just Gustarender updated) in case that's relevant. Note that this doesn't establish that the presence of the thin internal BT connector lead can't be detrimental to the sound - say if poorly shielded so is effectively acting as an antenna to pick up internal RF - just that it shouldn't be as a result of it acting as an active emitter of BT RF when non-BT inputs are selected. I still need to listen to my system with the BT connector cable attached vs not once my system is warmed up again.

In some ways of even greater interest to me is the sheer levels of RF in that Mhz-Ghz range generated by the internal circuitry - in some places it is as high as at the termination of the BT connector cable with BT selected e.g - such as over the 'bottom' of the ladder close to the front plate. Takeaway - quality of internal shielding, including segregation of circuit sections where possible is desirable in complex digital devices like the R26. I have a greater appreciation now for what LHY did with their SW-8, SW-10 and OCK-2 with their pre-cast aluminium chassis with divided internal sections. The packed interior of the R26 makes choosing locations for additional DIY shielding tricky, but the high RF levels suggest it may be worth going to some trouble.

@Stellabagpuss So given this I'm interested to hear your comments on internal shielding...

(OK, that wasn't as short as I intended - must get back to work)

 

[St12]

Hi, quick answer for now (work to do) is after a fair bit of testing in multiple locations over the R26 internals and back plate / connector area with a 3-axis RF meter it appears the BT transmitter is only on when the BT is selected as an input. There's a 4-6x increase in RF readings in the range my meter covers (50Mhz - 3.5hgz) with BT selected over baseline RF levels with other inputs selected. That's with my early model R26 from Aug last year with original firmware still (just Gustarender updated) in case that's relevant. Note that this doesn't establish that the presence of the thin internal BT connector lead can't be detrimental to the sound - say if poorly shielded so is effectively acting as an antenna to pick up internal RF - just that it shouldn't be as a result of it acting as an active emitter of BT RF when non-BT inputs are selected. I still need to listen to my system with the BT connector cable attached vs not once my system is warmed up again.

In some ways of even greater interest to me is the sheer levels of RF in that Mhz-Ghz range generated by the internal circuitry - in some places it is as high as at the termination of the BT connector cable with BT selected e.g - such as over the 'bottom' of the ladder close to the front plate. Takeaway - quality of internal shielding, including segregation of circuit sections where possible is desirable in complex digital devices like the R26. I have a greater appreciation now for what LHY did with their SW-8, SW-10 and OCK-2 with their pre-cast aluminium chassis with divided internal sections. The packed interior of the R26 makes choosing locations for additional DIY shielding tricky, but the high RF levels suggest it may be worth going to some trouble.

@Stellabagpuss So given this I'm interested to hear your comments on internal shielding...

(OK, that wasn't as short as I intended - must get back to work)

Could you, please, mark the most generating places of boards on photo?

 

[Jake2]

Could you, please, mark the most generating places of boards on photo?

Hard to be scientific and precise about it with a 3-axis meter, perhaps if I switch it to single axis, will have another look this evening. See what I can come up with.

 

[Stellabagpuss]

Hi, quick answer for now (work to do) is after a fair bit of testing in multiple locations over the R26 internals and back plate / connector area with a 3-axis RF meter it appears the BT transmitter is only on when the BT is selected as an input. There's a 4-6x increase in RF readings in the range my meter covers (50Mhz - 3.5hgz) with BT selected over baseline RF levels with other inputs selected. That's with my early model R26 from Aug last year with original firmware still (just Gustarender updated) in case that's relevant. Note that this doesn't establish that the presence of the thin internal BT connector lead can't be detrimental to the sound - say if poorly shielded so is effectively acting as an antenna to pick up internal RF - just that it shouldn't be as a result of it acting as an active emitter of BT RF when non-BT inputs are selected. I still need to listen to my system with the BT connector cable attached vs not once my system is warmed up again.

In some ways of even greater interest to me is the sheer levels of RF in that Mhz-Ghz range generated by the internal circuitry - in some places it is as high as at the termination of the BT connector cable with BT selected e.g - such as over the 'bottom' of the ladder close to the front plate. Takeaway - quality of internal shielding, including segregation of circuit sections where possible is desirable in complex digital devices like the R26. I have a greater appreciation now for what LHY did with their SW-8, SW-10 and OCK-2 with their pre-cast aluminium chassis with divided internal sections. The packed interior of the R26 makes choosing locations for additional DIY shielding tricky, but the high RF levels suggest it may be worth going to some trouble.

@Stellabagpuss So given this I'm interested to hear your comments on internal shielding...

(OK, that wasn't as short as I intended - must get back to work)

Thanks for reporting back the BT, and TBH it's as l suspected, BT is only operational when selected.
I personally think having the BT antenna connected will vary from user to user, depending what RFI they have,l removed my antenna on backplate, personally I don't think it will make much of difference,as it's already in a noisy box.

l would say,adding a Ground box to the unused connectors,would help with noise

Of course you could just add some additional sheilding,but it's inside the R26 like most DACs are full of noise, but in a nutshell, l covered all cables in copper tape, then insulation tape,to help reduce RFI. The PSU wires have no sheilding, what so ever, so it not complicated, monkey see ,monkey do.

The other area l attached is the rear of the front display, l made a cardboard template,with spacers so it won't make contact with the board. l used Rustins G Shield Eletrosmog paint to paint cardboard template, to help reduce RFI.

I also painted the internal section where the PSU sits with G Shield.

l will report back on the outcome over the weekend.

 

[Johnjc1]

I enjoy watching music videos via LDAC. Whilst not as good as files or streaming I can still enjoy so unfortunately the BT antenna stays put.
I have shielded and use grounding (another controversial topic) with the R26 so hopefully that negates the BT connection

 

[Jake2]

Thanks for reporting back the BT, and TBH it's as l suspected, BT is only operational when selected.
I personally think having the BT antenna connected will vary from user to user, depending what RFI they have,l removed my antenna on backplate, personally I don't think it will make much of difference,as it's already in a noisy box.

l would say,adding a Ground box to the unused connectors,would help with noise

Of course you could just add some additional sheilding,but it's inside the R26 like most DACs are full of noise, but in a nutshell, l covered all cables in copper tape, then insulation tape,to help reduce RFI. The PSU wires have no sheilding, what so ever, so it not complicated, monkey see ,monkey do.

The other area l attached is the rear of the front display, l made a cardboard template,with spacers so it won't make contact with the board. l used Rustins G Shield Eletrosmog paint to paint cardboard template, to help reduce RFI.

I also painted the internal section where the PSU sits with G Shield.

l will report back on the outcome over the weekend.

Nice work on all the shielding . I'm really enjoying all these first hand experimentation anecdotes in recent days especially from @rodthebod .

You and @Johnjc1 are preaching to the converted on signal grounding (and enhanced mains earthing for that matter via the Puritan Ground Master) to which I have found the R26 is very responsive. As a matter of interest did you ground the cable shielding to the chassis?

Background is I'd been contemplating doing the shielded wrap thing for internal unshielded power cables in my new Hypex Nilai where I have the luxury of acres of space by comparison to the R26. My understanding is shielding is more effective if it can 'drain' to ground otherwise it can just retransmit the RF/EMF it has received.