Romaz SR4 and ALEX DRs
A novel way to massively improve the SQ of computer audio streaming
My single- and dual-stage regulation power supplies from @[email protected] arrived a few weeks ago and I felt I owed it to Alex to comment on just how good these power supplies have been in my system:
First of all, the attention to detail and the build quality of these units are superb. Second, they do exactly what I hoped they would do -- noise floor drops and dynamics and control improve. They've improved everything I've connected them to including various cheap SMPSs I had lying around, a PowerAdd battery, an sPS-500, LPS-1.2, SR4, and SR7. While the improvement was smallest with a DR SR7, considering the low asking price for these units, even with the DR SR7, I would consider purchasing one. As the photo depicts, I have purchased 5 and I now have more on order.
The greatest beneficiaries among the PSUs that I've tried are the PowerAdd battery, sPS-500, and LPS-1.2 and for these PSUs, the dual stage regulation models especially are transformative. For these PSUs, the DXP-1A5DSC should be considered "must haves" imho.
Using a PowerAdd battery set to 16V and a DXP-1A5DSC with the pre-regulator output set to 15V and the final regulator output set to 13.5V, the drop in noise floor and the improvement in dynamics and control with my Hugo TT2 is just unbelievably better when compared against the PowerAdd by itself or against the stock 15V SMPS. It's like a completely upgraded DAC with this little device even though this DAC is powered internally with supercaps.
My LPS-1.2s have taken on new life as well. My units have largely gone unused as of late because with any components that draw close to their max rating of 1.1A, I have found these quickly lose steam (likely due to voltage sag) and in some instances, like with the etherREGEN, the LPS-1.2 is only barely better than the stock SMPS. Presently, I'm using one of my LPS-1.2s at 9V feeding a DXP-1A5S set to 5V which is then feeding my Monoprice SlimRun USB 3.0 optical extender and this combo not only provides me complete galvanic isolation between server and DAC but the addition of even the single-stage regulation power supply dramatically improves dynamics.
What about the SR4 and the new SR4-Turbo (SR4T)?
Because of the greater 2A headroom of the SR4s, these PSUs don't run out of steam as quickly as the LPS-1.2 and the SR4-Turbo especially maintains its composure with much more gear including any of the JCAT cards and most network switches that I've tried. The standard SR4 + DXP-1A5DSC (dual regulated) is roughly the equivalent of an SR4-Turbo by itself but an SR4-Turbo with this same dual regulated module takes it very scarily close to a DR SR7 with respect to dynamics for low power devices like the etherRegen or JCAT's latest XE USB card. At close to 400 GBP, especially with such a good exchange rate, I cannot recommend the SR4-Turbo more highly.
Where an SR7 continues to have an edge even over an SR4-Turbo + DXP-1A5DSC is with tonal density and color saturation. There also remains a relaxed and more effortless quality to the SR7 that sounds more natural and pleasing to my ears. Clearly, headroom matters even for low power devices. When you add the DXP-1A5DSC to a standard SR (single regulated) SR7, just like with the other PSUs, it sings bigger and bolder and blacker. It is still not exactly equivalent to a DR SR7 but to my ears, its 50-60% there.
Are there downsides or limitations to Alex's units? Yes, presently they cap out at 15V and 1.5A of output and this is due to the limitation of the LT3045s and so don't expect these units to power a big motherboard or high-power CPU. Alex is working on SR units that can output up to 20V and DR units with a final output of 15V and up to 2.1A and so this opens up the possibility of powering an i7 NUC with a PowerAdd battery.
The big challenge of course is heat. The internal parts used including caps, etc. are rated for >100 deg C. According to Alex, the LT3045 has a max input voltage of 20V (absolute max of 22V) but he recommends, based on the heat dissipation abilities of the chassis that is used, that you don't go beyond 4w of heat dissipation for an SR unit and 6w for a DR unit. That means for an SR unit with a desired output of 5V/1.5A, if your feeding supply is 7V, that amounts to 3w of heat that will need to be dissipated (2V x 1.5A = 3w) and so this should be acceptable. If your component only draws 0.5A, then your feeding supply can go as high as 13V for an SR unit. Hopefully, the math here is clear. Should you do something stupid and go significantly overboard, Alex has assured me that there are thermal safeguards in place that will prevent you from frying whatever gear you're powering. I think these recommendations are probably conservative because my units are barely warm to the touch.
Is there an advantage for using a larger spread? Yes, it sounds better. According to Alex, larger spreads result in less ripple. With the DR SR7, for example, Paul is using a spread of 7V and those who have compared an SR vs DR SR7 knows just how much better the DR sounds. If you're unsure as you place your order, it's probably best to discuss your plans with Alex. In my case, I am using a 12V rail from my SR SR7 to feed a DXP-1A5DSC with a 10.5V pre-reg and 9V final output to then feed an etherREGEN and the results are simply stunning.
As for the quality of the DC cabling used, not surprisingly, they make a big difference. I use the 16AWG OCC copper with JSSG360 shield that Ghent sells and they pair exceptionally well with Alex's units.
MacMini + Bridge ethernet thunderbolt
A novel way to massively improve the SQ of computer audio streamingOn 1/5/2017 at 1:15 AM, romaz said:
System Preferences > Network > Manage Virtual Interfaces
Once in Manage Virtual Interfaces, click the "+" sign at the bottom left of the screen and select "New Bridge".
Give this new bridge whatever name you'd like. You should have a selection of interfaces listed for you in the box to include in this bridge. Specifically, you should see your native ethernet port called "Ethernet". You should also see listed your other ethernet port that belongs to your Thunderbolt device. In my instance, this is called "Broadcom NetXtreme Gigabit Ethernet Controller" although yours may be called something else. Regardless, check the two ethernet ports you want included in this bridge and click "Done."
This should take you back to the previous screen. In the left window pane, you should see this new bridge you've created and its status. If it states "Connected", you may already be good to go. Regardless, make sure this new bridge is highlighted. Then look at the right window pane to see the specifics of this bridge. In the Configure IPv4 line, feel free to keep the "Using DHCP" option. This works just fine for me although if you feel compelled to create a static IP, you can do so. If you decide to use the "Using DHCP" option, then you don't have to bother hitting the "Advanced" tab, just hit "Apply" if you're not already connected.
You should be good to go. On my Mac Mini, it was that simple although you may require a reboot.
To verify that your microRendu is online, open up Safari and type in "www.sonicorbiter.com" and the control screen should come up. From there, make sure the HQPlayer NAA option is selected and you should be ready to play music. Let me know if this doesn't work.
Many thanks....I just found your instructions and implemented the bridged connection with results that were way more than just a pleasant surprise. (The link earlier in the thread to Apple support article on bridging is no longer working.) I bridged a Bricasti M5 Network Player to a modded 2012 Mac Mini with an Apple Thunderbolt to ethernet adaptor. Previously used a small managed switch. Over the last year plus have focused a lot on optimizing power and isolation of system and networking components with very good results using a direct spdif connection from the M5 to Dynaudio Focus XD400 speakers. Network modem, router, and switch are independently lps powered along with the Mini and the SSDs. Having done all that and experiencing quite good results I was recently contemplating next steps and wondering if I'd optimized as much as feasible short of upgrading the whole system itself. Bridging was an optimization I was definitely missing. So finding this method is a very pleasant surprise. Without getting into the details, it improved the sound across the board. Best $29 (Tbolt-ethernet adapter) high bang for the buck mod I could have imagined. Romaz again, thanks for the instructions and sharing...and thanks also to austinpop for moderating and organizing this thread!