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Post by MikeMusic on May 18, 2023 10:15:30 GMT
We used to ship printed items worldwide 80s and 90s
Brazil was the only place it was illegal to ship posters
Did it one time. They shipped them back
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Post by lucianosouza on May 18, 2023 10:27:21 GMT
Yes friends, brazilian customs is a dark place.
Thanks for the good vibes ands inspirations.
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Post by MikeMusic on May 18, 2023 14:53:12 GMT
All the best with it arriving soon
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Post by lucianosouza on May 18, 2023 15:29:48 GMT
Thanks Mike.
Today I purchased a R26 from Aliexpress.
I hope this can arrive with no problems, but is always uncertain here.
After the LB return to US I will find another way to bring then.
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Post by MikeMusic on May 18, 2023 16:18:30 GMT
Best of luck Luciano
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Post by rodders on May 19, 2023 11:32:35 GMT
      Been trying out a direct cable RG-402 R26 motherboard (MCX male connector) to BNC to LB clock. This takes away the short umbilical lead inside the R26 made using RG-316U. After taking off the top panel (front bolts in three pairs on the underside of the R26 and one centre rear panel on the top) It was a simple task to remove the nut on the rear of the R26 chassis holding the BNC male connector assembly -big spanner, don't use pliers! The small gold colour MCX connector on the factory supplied short MCX-BNC lead is just pulled upwards to remove it from the R26 motherboard. The right angle MCX connector allows the fairly stiff cable to naturally exit the hole left by the BNC connector. Thought about it before ordering anything. I ordered a RG-402 lead from Aliexpress with a right angled MCX-SMA at 1meter so I'd have some cable to play with for other tests. There doesn't seem to be any MCX male to BNC female available but no worries I had BNC connectors from other projects so used one to terminate the new RG-402 lead BNC to the LB. On first listen, things are noticeably better, but it will need some bed in time to get the best out of this upgrade. I have ordered a RG-405 with MCX right angle male to SMA to try out so it's possible to change cables with this setup, for tweaking, I have just done away with the possibly inferior RG-316U cable and of course some connections which is always a good thing, simplicity is best. The next thing is to try the LB PCB board INSIDE the R26, yes it will fit, the aluminium transformer partition is easily removable from beneath the R26, with three bolts. This would allow the partition to be modified to take the LB PCB with carbon fibre isolation between bracket and PCB, as it will be susceptible to micro vibrations. Power could be taken from the R26, any suggestions where a nice power tap could be taken, the regulators are just below? If this isn't practical then a LPS from outside could be used and would probably be better sonically, I just like the idea of putting the LB away inside, nice and neat and simpler. The USB is a bit awkward, I'll think about that..... All good fun. All tweaks are reversible, should you ever want to try something else...... and shouldn't void any warranty. Just worked out how to get pics here! |
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Post by MartinT on May 19, 2023 11:40:39 GMT
I have photos of these tweaks but how do I attach them, or is it not supported here? Yes, it can be done using one of the various hosting companies mentioned here, or by using TapaTalk on your phone. theaudiostandard.net/board/5/ |
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Post by rodders on May 19, 2023 11:45:03 GMT
Thanks Martin, I posted on another forum, Head-Fi about the Gustard R26 specifically so copied the link from there!
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Post by John on May 19, 2023 11:48:07 GMT
Excellent work
It is great seeing ideas being developed
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Post by John on May 19, 2023 14:01:51 GMT
I can see you inspiring Stellabagpus with this
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Post by HD Music & Test on May 19, 2023 15:13:14 GMT
A couple of obervations here,
The tranmission line may have a better insertion loss, though @ 10Mhz its bit spurious which is quite a low frequency for RF engineers, however its the WHOLE transmission line which is the key area here.
Hence why the length of the Mx type board form factor connector <> back panel is short.
Having longer cable in this configuration will leave you open to other RF issues imho (simple to measure as well with a good rf current probe)
There are other options to negate this issue and make it neater, so keep playing away Rodders
Having both the usb & dc power at the same time into the LB clock has always resulted in a degradation of the clocks overall performance I have found.
Having the blue tooth anntena in (when not being used) is another source of noise ingress remove it and cable and cap it off at the board its routed right past the main oscillator.
Why are you using XLR<> single ended converters? when use have singled end inputs anyway?
By using those adapters you are just Pseudo Balanced ( just by connected pins 1 & 3 togther) even if you using these ground 0Vdc reference return sink pathway, you are then introducing the noise from the ground chassis not the 0Vdc into the mix not recommended for optimum noise floor reduction.
If you can shorten the transmission line length from the clock, and use some RF sheilding gaskets and gromets plus a mini faraday cadge you may reap more of a better transmission line performance.
Nice to see a few folks thinking outside the box
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Post by stellabagpuss on May 19, 2023 16:12:05 GMT
I can see you inspiring Stellabagpus with this Funny it did cross my mind while l was doing my sheilding mods a few months back. l decided against it, simply l didn't want additional power cable and USB cables running into the R26, after spending the time shielding things and possibly bringing noise to both LB and R26. Fair play Rodders for trying, l would be really interesting to hear your views. Personally I would have left the LB in its case,that would help on the sheilding part. Of course you may be land locked on space. Myself l am thinking of removing the BNC input connection and running straight in using a Female BNC to mcx connector Actually l just realised l commenting on the photos of the LB inside the R26 that on Head Fi Doh... And not the ones posted on TAS. Your everywhere Rodders 🤣 Anyway...can't wait to hear your views on your Hot Rodded R26 🤣...No pun intended |
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Post by John on May 19, 2023 16:32:51 GMT
Nice to see a few folks thinking outside the box Or even inside the box |
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Post by rodders on May 21, 2023 9:47:27 GMT
   I've had a chance to try out version one of the LB clock inside the R26 this morning. Most enlightening. Well I can say that placing the LB inside doesn't ruin what it does, in fact it seems to improve things. I have had a few hours of very immersive listening. Having the top panel on the R26 does help the sound out so I'd say screening is important, lifting off the panel the sound becomes harder and more brittle, edit: strike that I've been listening for a few more hours and that brittleness when panel removed is gone now so maybe not so sensitive to the extra shielding from the top lid , the R26 internally is well shielded with the vertical aluminium panels separating each section. Perhaps an outer shield around the LB PCB would be worth trying though. Leo Bodnar made considerable effort designing the PCB so that the earth mass is connected to the aluminium sleeve and the end panels are all grounded to encapsulate the PCB properly. Having the PCB inside the R26 seems to add some integrity to the sound, on first listen things sounded quieter but there was more to listen too. I should mention that the only other difference to trying out the LB PCB inside was the feed to the board, I upped it to 7.5v from a Zero Zone LPS. This did make a difference compared to using a 5.2v feed from an Allo Shanti or a 5v feed from a Lipo04 battery bank, I tried all these voltages this morning. The 7.5v sounded best with a more immersive listen. If anyone wants to try this mod out it's important to get the order of feeding the cables through the 12mm rear panel hole right. Barrel power connector first, then SMA antenna connection then lastly the USB-B once you have cut off the PVC surround, there's no way it will go in otherwise. Notice the foam sticky pad with yellow PTFE insulation to prevent any contact with the capacitors underneath. These caps are the only items that could interfere. Please note that on this crude first attempt the LB PCB is almost floating in the space held by the connected cables. Not an issue but this should be able to be improved upon as the device showed itself as being prone to micro vibrations (it's a clock after all) , using RMS Basis mass dampers with carbon fibre helped things sound wise when I had the complete LB mounted on top of the R26. Comparisons to having the LB on top compared to inside, using the same RG-402 MCX-BNC cable, well I'd say that there is an improvement, I can't remember my system sounding better. I did add some aluminium tape to around the BNC connections as suggested by Stellabagpuss. Might be placebo I can hear some say............ but I would point out that the thing about this LB clock is that you must listen to the music, whole tracks or albums not just segments, it focuses the sound with a synergy that doesn't happen with the internal clock, all the notes are there but they are a bit mechanical, switch to the LB and there is a flow to the sound that's more natural and easy to listen to. I find the LB just more enjoyable to listen to, I will play whole albums now not wanting the music to end. Having a sensitive device such as the LB clock in a small lightweight aluminium sleeve isn't going to help it's performance, having it inside the chassis of the R26 which is built to a very high standard might be why it's working better and/or the fact it's sharing the screening.......... comments welcomed. If anyone wants links to the complete cables and adaptors that I've used let me know, I really would like to get to a working solution that doesn't require any messy termination of cables, with such short runs of cable 150-200mm effect of cable should be limited hopefully. I'm expecting terminated right angle MCX-SMA RG-402 and RG-405 (much more flexible) with a SMA-BNC adaptor. I have thought about using the existing BNC chassis connector for the LB GPS antenna with a suitable adaptor but it would mean machining ugly holes in the R26 for the power and USB cables, I don't want that. Next is to try out a proper aluminium shell for the LB for extra screening. |
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Post by rodders on May 21, 2023 10:17:54 GMT
Having found out about the LB and where its posted via Vic and then reading this thread I thought it only respectful to keep everyone updated on my progress
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Post by John on May 21, 2023 10:31:41 GMT
Thanks for posting on hear Rodders
Its good to know that your efforts have paid off
In my book it's all about the enjoyment of music and I hope it will inspire others
I was worried that the results might be worse as in a noisy area without any shielding.
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Post by rodders on May 21, 2023 10:36:58 GMT
HD Music & Test Many thanks for your comments all helpful and appreciated, I'll try removing the unused BT cable, but how do you go about capping the BT PCB mounted connector, just with a bit of aluminium tape over the shield careful not to short the hot connection? I have found that having the USB connected to be detrimental too, this is probably due to it giving power out and polluting a better, cleaner supply via the barrel connection to the LB, even shutting off the second BNC via the software seemed to make a difference. The XLR-RCA adaptors were a "why not see if it makes a difference" tweak, I saw from the R26 specs that the XLR outputs give out a higher voltage than the dedicated single ended RCA outputs so that made me want to hear the difference. Sure enough into my Conrad Johnson clone Valve preamp it gave better dynamics and punch to the sound using the XLR outputs. But you have me second guessing with your grounding comments so I'll try again to hear the difference again especially now the DAC is playing at a better level. How can I "shorten the transmission line length from the clock" I would have to bypass the BNC PCB mounted connectors on the LB PCB and attach from under the PCB? This I have thought about it, but not being experienced with RF I guess the outer shield screening would be paramount? Would a MCX connector be better? Would you pick the Output 2 being closer to the clock and slightly further away from the power regulators on the R26? Sorry for all the questions but you are the guy to ask!  |
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Post by rodders on May 21, 2023 10:38:39 GMT
Hi John
Yes I was surprised that there didn't seem to be a detrimental effect too, real acid test is to pop the LB back into it's box and try it on top again to compare.
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Post by stellabagpuss on May 21, 2023 12:46:03 GMT
Hopefully God..Sorry Tony will advise soon.
l have lot to thank Tony for in regards to tweeks, his experience is vast..we are lucky to have him on TAS
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Post by HD Music & Test on May 21, 2023 19:01:08 GMT
Hello Rodders
"I'll try removing the unused BT cable, but how do you go about capping the BT PCB mounted connector, just with a bit of aluminium tape over the shield careful not to short the hot connection?"
Can you let me know which exact termination this is, from memeory they are smaller than the MCX range.
If it is that MCX size then you can use this.
"I have found that having the USB connected to be detrimental too, this is probably due to it giving power out and polluting a better, cleaner supply via the barrel connection to the LB, even shutting off the second BNC via the software seemed to make a difference."
This is partially correct, they is another reason which involves using the logic control section and increased current draw but also two independant power supplies with different impedances.
"The XLR-RCA adaptors were a "why not see if it makes a difference" tweak, I saw from the R26 specs that the XLR outputs give out a higher voltage than the dedicated single ended RCA outputs so that made me want to hear the difference. Sure enough into my Conrad Johnson clone Valve preamp it gave better dynamics and punch to the sound using the XLR outputs. But you have me second guessing with your grounding comments so I'll try again to hear the difference again especially now the DAC is playing at a better level."
This is purely amplitude nothing more than a (non) ideal 5Vrms as opposed to 2.5Vrms (Industry standard is 4.4Vrms XLR & 2.2Vrms RCA) this is how Chord electronics and few other manufacturers 'heighten they sound' simply by ramping up the output voltage. (ouput impedance is 100 Ohms as well)
Human's instantly notice volume increases easily, throw into the mix hey my volume knob/digital indictator is showing the same output level but its got more ummph.
Level match each output using a SPL and perform the same listening again see if you feel the same?
Its not true balanced configuration by tying the ground and sheild togther you are really defeating the object of the excerise imho.
"How can I "shorten the transmission line length from the clock" I would have to bypass the BNC PCB mounted connectors on the LB PCB and attach from under the PCB?
This I have thought about it, but not being experienced with RF I guess the outer shield screening would be paramount? Would a MCX connector be better?
Would you pick the Output 2 being closer to the clock and slightly further away from the power regulators on the R26?"
These are the questions here that for myself I would be looking at totally different approach, personally I would install a better clock inside with a dedicated 5Vdc ultra clean supply (there is just about enough room to do this I feel with some custom made boards etc.)
Ideally with reference clock signals, shorter transmissions lines and quality cables and connectors are basic, the Bodnar clock doesn't realy lend itself to be installed inside, it wasn't designed for this. its just a Ublox module with a slick gps slaving circuit. I recommended these for you chaps as its was a sensible price for a respeactable performance.
You could mount the clock so the RF output is 90 degrees so they cable routing for both power and RF are reduced to a more manageable solution? You could use MCX instead of BNC connectors it would require a bit of board work and some adapters?
Question for you guys what Voltages are you using to power these, we have found (with stock internals) 7-7.5Vdc seems to be the sweet spot imho. t can accept more but you are then disappating a lot of more unused engery into heat.
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