The true experimental tweak thread

[lmitche]

1 hour ago, lmitche said:

I did some sleuthing and the Sigma 11 should work with your 15 volt ac transformer Just get one set for 11 or 12 volts dc output and run into Michaels boards.

Cornan,

 

How much voltage did you want to get out of the two Stammheim boards?

 

Larry

[lmitche]

1 hour ago, Cornan said:

 

50VA balanced & floating AC-AC PS 15VAC> Sigma 12 14VDC> HC-HPULN 13VDC> HC-HPULN 12VDC> Brooklyn DAC

Think about 13.5 volts out of the sigma 11 instead or 14. 1.5 volts vdrop isn't great but it will work. You have to ask the vendor to install the correct resistor value for a given output. The little pot thingie doesn't have much range on these boards.

 

The hcpulns should handle a vdrop of .750 volts just fine.

[lmitche]

22 minutes ago, mozes said:

I want to share my experience of adding the Kemet polymer caps that @Cornan recommended. I added one to the output of the LT3045 1A board that feeds my HDD. I was skeptical about these caps, but I was surprised and I found that the bass got deeper and the highs are more extended.

Question, how does the capacitance impact the sound? What if we use other premium caps like Mundorf? 

Moses,

 

Do you have avlink to the specific Kemet cap you purchased please?

 

Thanks,

 

Larry

 

P.S. try ground shunting the neutral DC input on the HDD lt3045 DC input side.

[lmitche]

51 minutes ago, mozes said:

Thanks for the tip, will try it. Here is the link

https://www.mouser.ca/ProductDetail/KEMET/A750MS567M1EAAE015?qs=M6jHmRuQorWa3alz81gcwg%3d%3d

And thanks for the reference!

[lmitche]

3 hours ago, Cornan said:

 

Unfortunately the seller of S12 informed me that 13,5VDC is not possible with a 15VAC input. He suggested that I change the transformer secondary to 18VAC. I have asked him for guidance to perform this on my AC-AC ps. Should just be a matter of changing one cable for another one, but I want to be ansolutely sure that I’ll get the right one! ? 

I changed the S12 output to 14VDC/2A or 16VDC/2A depending on what is possible or not with 18VAC input.

Yes, or ditch the s12 idea and just change the 15 volt transformer to 11 or 12 volts and run ac directly into Michael's LDO.

 

Michael can tell you what voltage is best.

[lmitche]

1 hour ago, Cornan said:

 

Yes, that is one on my mind right now. However, I still want the S12 since it is an interesting voltage reg. Two in series is greater than one, so three could potentially be a good thing! ?

Now I just need to open up the balanced AC-AC ps and learn how to rewire it for 12VAC or 18VAC output. ?

If you haven't met him you should head over to http://sjostromaudio.com. There is no doubt that he can help you with your transformer swap. I hear he is a great guy and lives in your neighborhood so there is no excuse. I'm sure he has lots toys you are going to enjoy. For example I see a lt3045 was recently added to his product list.

 

I look forward to hearing what you learn.

[lmitche]

3 hours ago, Cornan said:

I have resolved my issue with the 15VAC balanced AC-AC ps now. Solution was to order another 12VAC balanced AC-AC ps to power the two HC-HPULN boards in series directly and to change my S12 dicrete voltage reg to 9VDC output (instead of 14VDC) so I can use it to power the ISO Regen with a couple of LT3045s in series. With 9VDC out of the S12 I will have a more universal solution as well since I can choose to power the Aqvox switch or BluWave board as well. I just left a bigger hole in my wallet. Life goes on!  

Great to see you end up in a happy place!

[lmitche]

26 minutes ago, hurka said:

OK, Hurka fess up! Where does this come from?

 

?

[lmitche]

7 hours ago, hurka said:

https://item.taobao.com/item.htm?spm=a1z10.1-c.w4004-9914611358.23.161f5604tteadx&id=565221839314

Many thanks!

[lmitche]

3 hours ago, Cornan said:

 

I have JSSG on DC cables, ethernet cables and USB cables to all of my devices, but not on AC mains cables though. However, I know that @lmitche have dressed his AC mains cables with JSSG. I think that went quite well, but he might chim in to let you know exactly how good they where. 

All of my cables are also starquad wired, but you should keep an eye open here since there is coming in new reports that Supra Cat 8 with its differential pair twist (plus JSSG) is a better cable than Carare 4S6 (with JSSG). I have order 5m of the Supra Cat8 to give it a try. I will report back here how they improve upon Carare 4S6 with JSSG. I hope to get time to do it on saturday atleast.  

Hi Micael,

 

Well I only did the JSSG thing on the ac cable going to my music servers ATX power supply.  I can't say it made a difference in SQ, unlike DC, network and USB cables where it really matters.

 

All for now, Larry

[lmitche]

5 hours ago, charlesphoto said:

 

I have one coming for inbetween the LPS-1 and microRendu. I’m planning on connecting the LT3045 to the LPS-1 direct with a dc barrel connector (sort of like hanging the microRendu off my dac with the Uptone UPCB) and making a little lego stand for it, and then my Supra CAT8/Oyaide dc plugs after that. Has anyone else tried this?

I run the cable from the lps-1 to a stack of two lt3045s joined with standoffs. The cable connects directly to the lt3045 screw teminals so the only connector is on the lps-1 end. From the lt3045 output a one inch cable leads to a right angle plug and then into the ISO Regen.

[lmitche]

2 hours ago, Cornan said:

One more thing. It surely improves with burn-in (despite I am a non-beleiver in burn-in). The SQ have turned more crisp lately. From top to bottom. In a fuck-it type of way! ? Dynamics have improved vastly over the last 30 minutes or so. Cool! ?

In my experience it takes 48 hours for the lt3045s to settle. It will get better yet.

[lmitche]

A Sigma 11 feeding lt3045s is a great combo. I just received two more sigma 11 boards from China. Will do the integration tomorrow. It's exciting, I'm a few days away from my completing my "dream" system.

[lmitche]

22 minutes ago, tims said:

How long would you say it typically takes to ship the sigma11 boards from China - the website advises anything between 3 to 7 weeks.

Thanks

This last batch was ordered on May 6th and arrived yesterday to my mailbox in the US, so almost three weeks.

[lmitche]

6 hours ago, BigGuy said:

I was going to build an LPS from this S12 module...

https://www.ebay.com/itm/S12-Super-regulated-linear-power-supply-board-5-30V-LPS-10000uF-50V-Versio-PSU/132048787951?hash=item1ebeb899ef:g:odUAAOSwbopZPMnE

which seems to have more heat sinking than the dual supply you found.  I would prefer not having to worry about heat or its side effects or need to modify the LPS to deal with this issue.

IF neither heat nor "artifacts" will be an issue, this will take care of my reqs for [email protected] and [email protected] plus eliminate a box.

Currently I am using no LT3045 regulators.

Hi Frank,

 

Nice catch! Yes you want the sigma 11 boards with the four heatsinks on the rectifiers and two big black 10,000 uf caps. 

 

I have made five lpsus here with these boards, three single, and one dual box. They are excellent lpsus for our use here but be careful, the mosfets fail when shorted. I have learned to unplug them, make all Dc connections, and lastly connect the AC power.

 

These things power multiple lt3045 chains here so I usually buy them in odd voltages like 7, 9 and 15 to have room for 1 volt of vdrop in each of the lt3045 boards.

 

You have to change one of resistors to make a major voltage output change as the blue pot has only about 1 to 1.5 volts plus and minus. You may also need to change out the transformer.

 

Make sure the mosfets are truly insulated on the heatsink or case floor as otherwise weirdness happens.

 

You can find these in nice cases already pre-made with one, two or three transfos and regulator boards inside. These cost roughly $100, $200 and $300 respectively plus shipping. I have one of these as well and it is very nicely done.

 

Larry

[lmitche]

40 minutes ago, BigGuy said:

Appreciate the watch-out on hooking up the LPS!  No need to let smoke out of box.  ?

 

Can you provide more detail on what to look for re mosfet insulation?

 

I will have to look for LPSs based on S11...maybe one with double output, e.g., [email protected] and [email protected].

You need to use your multimeter to ensure the mosfets tabs are not touching the case or mounting nuts and bolts.