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

May 22, 2023 at 7:12 AM Post #6,046 of 9,904
LB inside R26 progress.

I have been using a pair of Neutrik XLR-RCA adaptors on my R26 and I have been busy trying out the XLR-RCA adaptors compared to using the dedicated RCA outputs from the Gustard R26 outputs this morning. I have been living with the adaptors which give a pseudo balanced output, so not proper balanced but the voltage is higher at 5v.

I know that the increased voltage will give more volume as you kindly pointed out and when changing over the connections I tried to compensate for this. Listening to Diana Krall Sway I was definitely hearing more detail and texture on the brush on high hat at the beginning of the track with the XLR connection, the sound is just more alive, the difference is subtle but there.
I swapped over several times to confirm this, I must try the Jennie test (my dear wife) for confirmation but she was busy doing shopping etc. I should try the test with using my single ended Avondale Grad One solid state preamp which hasn't been heavily tweaked by myself like the Conrad Johnson clone has.

Next, after a suggestion from a prominent 'The Audio Standard' forum member on the LB thread, I tried disconnecting the BT antenna cable from the R26 vertical board with the streamer and LAN USB and Optical connections. I thought that the antenna would only be powered when the Bluetooth input was selected as the desired input, I think this is incorrect now. I placed a bit of heat shrink over the exposed antenna connector as I didn't want it to short anything on the motherboard. I just left the connector on the PCB open with no blanking.
The result, after trying to hear small difference's between XLR and RCA, was quite a wow moment, disconnecting the BT antenna made a big difference in detail and space around instruments instantly. A definite improvement. It may be that the LB PCB is being affected or that the BT antenna degrades the onboard R26 clock?

If the BT antenna is making this much of a difference then it is logical to assume that further screening is a good move around the LB. My next move.

Can other please try this disconnection of the bluetooth antenna internally, I'd like to hear back from others if it effects R26 owners without an internal Leo Bodnar clock!
Nice tip re the Bluetooth antenna, I’d removed the external one for that reason and I had wondered about its transmitter state when BT input is not selected, given there’s no firmware settings option to turn it off. I muat try it. Some great experimentation Rod, keep em coming.
 
May 22, 2023 at 7:46 AM Post #6,047 of 9,904
I received the Bodnar clock.
How should I configure it?

Capture d’écran 2023-05-22 à 13.35.00.png


There's a GPS antenna inside the box.
I presume that I don't need to connect it to the clock… Am I right?
 
May 22, 2023 at 8:10 AM Post #6,048 of 9,904
You will need to download the software on the Leo Bodnar site
http://www.leobodnar.com/shop/index.php?main_page=product_info&products_id=234
Aerial needs to be attached I have mine placed on the window
Connect via USB and software
If you see my first post on this I shared a picture off the settings I use
Just have one output selected
16ma
BW 9
And once configured set to sleep mode
You should do this every 3 to 4 weeks
Aerial stays connected
 
May 22, 2023 at 9:24 AM Post #6,049 of 9,904
Aerial stays connected
Aerial is the antenna?
And being once configured, can I disconnect it from USB to bring it next to the DAC, and power it with 5v?
 
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May 22, 2023 at 9:55 AM Post #6,051 of 9,904
Aerial is the antenna?
And being once configured, can I disconnect it from USB to bring it next to the DAC, and power it with 5v?
The LB clock can be powered by the USB alone although this isn't recommended full time as you will be bringing your PC or Mac into the DAC system power.

It will need power from a decent LPS at optimally 7.5v (just seems to like this voltage to get the best out of it there seems to be a general consensus on this) or a battery bank at around 5v will work via the barrel power connector. It's more practical configuring the LB whilst connected to your Mac and to the R26, once configured select sleep mode which turns off the logic circuitry and saves the configuration until next power down. If you unplugged the USB without power to the barrel connector the LB would lose it's settings after being tethered with the GPS satellite. Although I believe it goes back to the last used settings from what I've noticed.

Like Jake suggested you should only have only one output selected either 1 or 2 depending on which BNC you used, i.e untick one of the unused outputs, I found it makes a difference to SQ.

I would also add that if you are putting the configuration circuit to sleep then the antenna is not doing anything, only when you restart the LB and rerun the config to sync things up with the GPS satellite. It can be removed if you want. In some ways having a dirty great long RF cable attached to the LB whilst listening makes me a bit nervous, what's it adding in terms of interference..... might address that with the internal LB I'm working on.

It's all trial and error.......
But I'm so impressed with the LB inside the case without any extra shielding I don't want to mess with it, been listening all day.
 
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May 22, 2023 at 10:37 AM Post #6,052 of 9,904
Thank you all for useful the instructions.

Last question, is it impossible to use both 10 mHz outputs of the clock simultaneously for two devices?
For instance, one for the R26 and one for the DI-20HE?
 
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May 22, 2023 at 10:40 AM Post #6,053 of 9,904
Thank you all for useful the instructions.

Last question, is it impossible to use both 10 mHz outputs of the clock simultaneously for two devices?
For instance, for the R26 and the DI-20HE?
Don't see why not, that's what it is designed to do after all. I haven't tried though only have the one 10Mhz output capable R26 device.
 
May 22, 2023 at 11:03 AM Post #6,054 of 9,904
I use both outputs with the R26 and the DI-20HE. I played a few tracks, and it works.
Before comparing it to the OCK-1, I presume that there's a burn-in period for this clock.
How long was it for you?
 
May 22, 2023 at 11:05 AM Post #6,055 of 9,904
If you don't use BT then do this..........

It's worth mentioning separately, that today I found removing the tiny antenna connection from inside the R26, cable to vertical streamer board, made a world of difference.
This is a quote from 'HD Music & Test' a highly acclaimed member from the TAS (The Audio Standard) forum. He has kindly been helping me with my efforts on integrating the LB clock after I decided it might be a good idea.

"All of the BT internal antennae in those Chifi dac's are just an afterthought its the coax from the board to the antenna that acts like a big RF pick up always have beneficial results in removing them"

Well I can say with confidence, having reaped the benefits today after listening for most of it, that removing that little piece of wire from the board (I still had the chassis arial attached) reaps dividends.
It cleans the sound like you wouldn't imagine. This may be because I'm using the LB inside the R26, and it is benefiting, but I suspect disconnecting BT will be beneficial for non modified R26 users too.

Just passing on info......
Putting the connector back is simple and requires a careful push against the PCB connector, or pinching the vertical PCB with your fingers and the connector in-between.
It will connect back with a reassuring click if you so desire so no harm done if you want to try.

Now I know the that internal BT antennas are so bad for the sound, I am going to be using the R26 BT SMA female chassis connector to enable the LB clock antenna to have an external connection for convienience. Connections can always be put back the way they were supplied from the factory...... in the future.
 
May 22, 2023 at 11:12 AM Post #6,056 of 9,904
I use both outputs with the R26 and the DI-20HE. I played a few tracks, and it works.
Before comparing it to the OCK-1, I presume that there's a burn-in period for this clock.
How long was it for you?
I've had my LB since mid April so only a few weeks use, but it seems to be getting better and better, mind you I am moving the goalposts a bit ............ removing from it's case and trying inside the R26.....

Interested on hearing how you get on comparing, I would say give it at least whole tracks to listen to and not just snippets or fragments of tracks. Whole albums are best.
Then go back to the other clock.
 
May 22, 2023 at 11:24 AM Post #6,057 of 9,904
I'll give it a few days to burn-in, before comparing it to the OCK-1, and commenting about it.
 
May 22, 2023 at 11:31 AM Post #6,059 of 9,904
If you don't use BT then do this..........

It's worth mentioning separately, that today I found removing the tiny antenna connection from inside the R26, cable to vertical streamer board, made a world of difference.
This is a quote from 'HD Music & Test' a highly acclaimed member from the TAS (The Audio Standard) forum. He has kindly been helping me with my efforts on integrating the LB clock after I decided it might be a good idea.

"All of the BT internal antennae in those Chifi dac's are just an afterthought its the coax from the board to the antenna that acts like a big RF pick up always have beneficial results in removing them"

Well I can say with confidence, having reaped the benefits today after listening for most of it, that removing that little piece of wire from the board (I still had the chassis arial attached) reaps dividends.
It cleans the sound like you wouldn't imagine. This may be because I'm using the LB inside the R26, and it is benefiting, but I suspect disconnecting BT will be beneficial for non modified R26 users too.

Just passing on info......
Putting the connector back is simple and requires a careful push against the PCB connector, or pinching the vertical PCB with your fingers and the connector in-between.
It will connect back with a reassuring click if you so desire so no harm done if you want to try.

Now I know the that internal BT antennas are so bad for the sound, I am going to be using the R26 BT SMA female chassis connector to enable the LB clock antenna to have an external connection for convienience. Connections can always be put back the way they were supplied from the factory...... in the future.
Interesting! Presumably the connector on the vertical board simply pops off…did it need much of a tug? Taking care not to rip out the socket 😉

Great work! Now get those TXs out of the chassis and the clock in their space 😀. I know, a step too far…
 
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May 22, 2023 at 11:36 AM Post #6,060 of 9,904
f you are you using burned in cables, that will be a lot of the burn in done but I’m sure the clock will benefit from 24 hours or more burn in.
I'm using the 50 ohms cables that were used with the OCK-1.
The LB clock played only a few tracks. The sound may be a bit punchier than the OCK-1, but it is less precise, and bass are a bit heavy.
I think that it is simply too early to have an opinion, and to post comments.
 
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