SOTM tX-USBultra impressions

[elan120]

On 1/19/2018 at 6:50 AM, doraymon said:

On a similar note, what do you guys think of the opposite effect?

Will a lower performance re-clocking device downstream the tX-USBultra deteriorate the signal?

More specifically, I have the following system:

 

Mac Mini Roon Server > AQVOX AQ-SWITCH-8 > SOtM sMS-200ultra > SOtM tX-USBultra > Singxer KTE SU-1 DDR > Holo Audio KTE Spring DAC L3  > Pathos Acoustics Aurium > MrSpeakers Ether C Flow / Focal Clear

 

In this system the SU-1 is needed to transform the USB signal to I2S and feed the Spring DAC and although it's a fantastic (modded) D/D converter, its clock is probably not at the level of the one in the tX-USBultra.

 

On 1/20/2018 at 8:17 AM, doraymon said:

Thanks for the hint  and guess what, configuration 2 seems to sound better than 1.

That is, the sMS-200ultra and the tX-USBultra (both powered by an sPS-500) feeding directly into the Spring's USB seems to sound much more detailed than through the SU-1. Also, the bass sounds tighter but a bit dryer than solution 1.

 

Regarding the SU-1 PS upgrade with an LPS-1 I think I will not get any improvements over my actual SU-1 as this is the KTE - DDR upgraded version. 

I won't go into too many details but I trust my SU-1 is almost as good as the SU-1 can get.

 

I am on a path that could reveal part of your question regarding whether SU-1 internal clock could deteriorate the signal.  My plan is to add SOtM txUSBexp (clocked by sCLK-EX) and txUSBUltra in front of SU-1, and once it is settled down, I will then add sCLK-EX clocked SU-1 to compare with non-sCLK-EX clocked SU-1.  Hopefully, sCLK-EX clocked SU-1 will have a clear step up in SQ, which will somewhat answer your curiosity.

 

On the other hand, I just briefly look at what KTE DDR upgrade is offering, and it is clear that there is room for additional improvements if you still want to pull from your SU-1.  Overall, KTE DDR upgrade does offer good improvement over stock SU-1, but it replace only 1 of the 5 voltage regulators on the main board that feeds the Xilinx FPGA and few other devices.  If you replace (upgrade) the other 4 voltage regulators feeding XMOS, USB input oscillator (24.000MHz), and both Crystek CCHD575 sampling oscillators (22.5792/24.576MHz) will further improve overall SQ.

 

As a side note, the 4 voltage regulators mentioned earlier include one switch mode DC-DC voltage regulator will receive good benefit by using linear regulator instead.

 

This is my $2.5C...hope they are somewhat helpful...

[elan120]

3 hours ago, str-1 said:

A question to those with some experience of taking the board out of the tX-U (for whatever reason), or any similarform SOtM device.  In putting the board back in, how have you secured it to the chassis? 

 

Looking inside my tX-U I see that the board is held securely in place with blobs of some kind of plastic material.  I am assuming these blobs are no longer usable when the board is removed so I am wondering how best to re-secure the board if I ever had reason to take it out.  Thanks in advance for any advice.

The blobs of plastic material is hot glue, they can be loosened or removed by rubbing alcohal.  To remove the board, you can either carefully loosen the hot glues on the board side by soaking small amount of alcohal, but careful not to loosen them from the case, this way, board can be re-inserted back into the hot glue blobs.  The other way would be remove the hot glues altogether and then re-apply them when boards are put back.

[elan120]

5 hours ago, str-1 said:

Can anyone offer a view on how long it takes to fully run-in a new tX-USBultra with Evox caps?  I’ve got one arriving today.

My experience with Evox caps burn-in is about a week to just over a week; after that I normally can't tell if there are more changes.

[elan120]

11 minutes ago, johndoe21ro said:

Can you tell us anything about the changes in sound? 

Mostly in improved dynamic.  Once the burn-n process is completed, it is quite easy to observe the change, and I would highly recommend it, especially if you are comfortable to install the cap.

[elan120]

14 minutes ago, johndoe21ro said:

That's good to know. Can you be more specific about what Evox caps are we talking about? (value, link, etc.)
Thanks! ☺️ 

Since this is an upgrade originated from SOtM, it is best to request this information from them instead.

[elan120]

10 minutes ago, johndoe21ro said:

I was wondering, has any of you tried to shorten the internal (and too long) MCX (male) to BNC (female) cable inside the tX-USBultra instead of replacing it? I have the 75ohm BNC clock input.
Thanks!

FWIW...for the amount of work involved to do it right shorting this cable, it might be worth while to just purchase a new one instead, but on the other hand, for the amount of improvement from shorter cable, the effort might be more justifiable to apply elsewhere...such as Evox cap upgrade.