Salas SSLV1.3 UltraBiB shunt regulator

After replacing with 75k resistors everything powers up and adjusts to the appropriate range perfectly. Thank you for your help!

The thicker leads of the .5 watt resistors I used made desoldering and resoldering more difficult, but I finally got them swapped.

For your 15V target with 10k trimmer you may even leave vrr out if a 75k isn't handy to replace.
 
I am running a dac directly to Sennheiser 650s so my comparison are only based on that for now. I think the ultrabib sounds more balanced than the previous supply, possibly more control over the mid-range, toned down the transients a bit while maintaining depth and soundstage. I also swapped out the DAC psu for an l adapter.

I am building more ultrabibs to run dual mono and reflektors to try different combos and will see.
 
I added the second set of ultrabibs to try dual mono for now (there are some parts differences and I will be building the second set to swap in). I used Mundorfs for the reservoir caps and takman resistors. For the dual mono utrabibs, I'm using the lower current diodes in D-4 and lower current parts in M1.

The sound is really really good. I am only driving Sennheiser 650s directly for now, so some of this may be from increased power to drive the headphones but the sound is more 3 dimensional, holographic, stronger bass and more balanced sound overall. The transients were a bit pronounced before and this even things out nicely. I can't comment on whether going dual mono with the original supplies would deliver a similar bump in sound quality. I look forward to trying this with speakers when I have an amp available to run.

I plan to try film bypass caps and a discrete output stage with another version of this dac and will see how that compares.

Thank you for the solid kits Salas and Tea Bag!
 

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heat sinking

Salas:
I'm doing a dual mono with UBiB 1.3's for my Aleph J. Separate Pre. It is in a DIY 4U/300 box so floorspace is a little tight. Could I just use 1/4"x 2" Al bar on edge, something like 4'' a side be ok for heat dissipation. Dual Antek 4220's. That's about it in this box. Going to join it with the DCG-3/DCSTB pre. At my experience level I am really just guessing at the topology. I think it is what I am looking for though. Just hoping my ignorance will be audio bliss. :D
R,
Don

PS: The boards are great and Tea went out of his way to help so a great big thank you.
 
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By the way, powerful capacitance multipliers for filtering the rails are a popular add on in modern DIY amp builds. They still follow the raw DC level peak power sag, they aren't voltage regulators, just noise/ripple eaters.

Maybe L-Adapters could tackle such an amp as a whole. Stabilized rail power amps were always rare and expensive. At least twice as complicated. Extra dissipation from the power regulators is also added. Sometimes four of them are used in a stereo amp to minimize crosstalk. Reliability suffers with complexity too, not only the the pocket and thermal budgets.
 
62C on the tab its no problem for this FET. Say you burn 3W on it, RθJC 1.7C/W makes 67C inside. But it dies at 175C inside.

I'm getting higher temps now on one +/- set of Ultrabibs running at 325mA and 15v. M2 on the +/- boards are getting up to 70-75c. This is hot, but still seems well below their max temp. Is that okay long term? The other set running at 200mA are about 10-15c cooler.

Q2 on the L adapter is getting up to 70c it seems at 5v and the DAC is drawing maybe 500mA (possibly higher with higher res files). My AC voltage is measuring 125V on the mains, 18.5 on my transformer with 15v secondaries and 10.8v on a transformer with 9v secondaries. This seems high and might be contributing.
 
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Those small aluminum bars you now got as UBiB sinks are not forever. When you will fix the build prefer the perforated bottom plate as a cooler and temps will drop significantly on the power semis. Be careful with their insulation then. No tab should show continuity to the plate. Meanwhile evaluate your settings to not run more than 150mA spare current above loading consumption in the shunts. Highish secondaries surely contribute heat to UBiB M1s and to the L-A's Q2 pass transistor.
 
I scratched the pcb mask on the left side around the capacitor pin. It looks like there may be a solder bridge between the pcb underneath and the capacitor pin solder pad. Should I try to remove the solder or would this be the same copper plane the capacitor pin is soldered to?
 

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Upgrade from SSLV 1.1 BiB to 1.3 UltraBiB

Received Tea-Bag's board and minikit on Saturday and spent a few hours putting the new regulator together over the weekend. I am upgrading my +15V/1A power supply to the Auralic Aries mini streamer from SSLV 1.1 to the 1.3 UltraBiB.

This thing is very straight forward to put together and got dialed in +15.5V with only a few turns of VR1. Voltage was rock solid. It fit into the old 1.1 BiB footprint easily.

I noticed more details and more dynamics right away. Very worthwhile upgrade from 1.1.

I was worried about thermal at 900mA CCS but the hottest component is M2 which gets up to +55C after running for an hour. So looks like it's in good shape.

Thank you Salas for the excellent design and thank you Tea-Bag for helping us with boards and minikits.

Mike
 
I scratched the pcb mask on the left side around the capacitor pin. It looks like there may be a solder bridge between the pcb underneath and the capacitor pin solder pad. Should I try to remove the solder or would this be the same copper plane the capacitor pin is soldered to?
pretty sure that pad is part of the ground plane, use multimeter to double check.
 
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Received Tea-Bag's board and minikit on Saturday and spent a few hours putting the new regulator together over the weekend. I am upgrading my +15V/1A power supply to the Auralic Aries mini streamer from SSLV 1.1 to the 1.3 UltraBiB.

This thing is very straight forward to put together and got dialed in +15.5V with only a few turns of VR1. Voltage was rock solid. It fit into the old 1.1 BiB footprint easily.

I noticed more details and more dynamics right away. Very worthwhile upgrade from 1.1.

I was worried about thermal at 900mA CCS but the hottest component is M2 which gets up to +55C after running for an hour. So looks like it's in good shape.

Thank you Salas for the excellent design and thank you Tea-Bag for helping us with boards and minikits.

Mike

Mike hi, you are welcome. Nice that you liked it. Can it be you set rather much spare current for the job so M2 is the hotter spot? Maybe feasible to hold it back a little.