The true experimental tweak thread

[sandyk]

23 minutes ago, One and a half said:

Ah, that’s how they get around the low noise, by not dissipating so much heat when higher voltages on the LM series.

 

 The Data sheets don't cover this area too well, and seem to be suggesting that the noise is the same at both just above the drop out voltage, and much higher. The highest the graphs show is with a 2V Input/Output Differential, and it is still only .8uV noise  Out. This pleases me as I will soon be trying a 3.3V LM78XX pinout LT3045 in the input stage of my DIY DAC, using the +5V rail for it's input.

The 1MHZ bandwidth is a major improvement over the older VRegs, but still nowhere near the bandwidth of the Paul Hynes regulators.

[mourip]

3 hours ago, Balázs said:

Thanks @mourip I think you are using the standard adjustable output of the HDPLEX. This is certainly okay but  your input is a relatively low quality (ripple noise is >3 mV(!)) DC signal provided by the LT1083 regulators of the HDPLEX.  What I am trying to do is opening up the HDPLEX and "grabbing" either the secondary AC voltage at the secondary side of the transformator or the AC signal directly after the KBPC5010W bridge rectifiers of the HDPLEX and use this as input for the high quality LT3045s.

 

You're dropping 1 Vdc on the LT3045. Considering what I'm trying to do there's much more to "burn"  because of the 200W powerhorse in the background. Any idea how to do it?... My only idea is to use a still good quality (<40 uV ripple noise) pre-regulator like the one mentioned in this thread earlier.

 

Ah. I understand now. My demand on the 3045 add-on board is pretty low.

 

Regarding the HDPlex. Am I correct in assuming that by adding the secondary regulator I am overcoming the greater ripple of the HDPlex by using it as a pre-regulator to drop down the input voltage to the 3045? I have assumed that the 3045 would make up for any lower specs in the HDPlex.

[gstew]

6 hours ago, tapatrick said:

Thank you Greg for the invaluable info and full reply! VERY much appreciated and really helps.

 

I've been looking into Ian's boards which is another interesting direction to go in. His products seem to be very well thought out and executed but also a bit complicated to get them. Too many choices now to pursue...:) Do you have any of his products?

 

I am drawn to his FIFO I2S isolator with the dual clock board, which would then have to go with the RPi. Needs further study to understand how the components and software will all fit together so I don't get it wrong.

 

Cheers Patrick

 

 

 

Patrick,

 

I'm glad that was useful.

 

The 2 DIY DAC builds I'm working on now will use an Ian FIFO stack each before the DAC. They will also be fed from RPis... I'll be trying them with / without Kali's & Isolators to see if they make a difference in this build. The DAC cards are Twisted Pear Buffalo-IIIPro cards, one using the ES9028 and the other the ES9038.

 

Before heading down this path, you want to consider how much of your source is native DSD. MOST RPi distro/SW setups (so far, AFAIK) don't do native DSD. Some will output DOP. Ian's Isolator board can be fitted with a DOP to DSD converter board. BUT I'm not sure many (or even any) RPi setups will playback native DSD. DON"T take what I say here as gospel, I'm not following this realm closely at this time as all of my source material is PCM. AND the FIFO II is also (again, AFAIK) a PCM-only device. 

 

AND if I have missed recent developments in RPi DSD, someone please bring me up to speed!!!

 

But if you, like me, have all PCM-based source files, read on.

 

Ian's FIFO II is a reclocker, in this setup the isolator is another board. To feed your Directstream Jr with the FIFO II via the AudioGD I2S to HDMI board, you want to get the FIFO II, a Dual XO Clock board, and the FIFO II Isolator board mini kit (and if you don't do SMD assembly, you'll need to find someone to assemble the Isolator board for you). This Isolator board (in this case) goes between the FIFO & Dual XO Clock board. Also the Dual XO Clock board can be had with or without clocks. You'll want to get it with clocks and use them to get the setup up an running. BUT the supplied clocks are not low-jitter units and only intended for testing the operation of the setup... after getting the setup running ok, you'll want to replace them with a pair of something like Crystek CCHD-957 clocks to really get the benefit of the FIFO Reclocking.

 

Finally, while I suspect you'll get a benefit using Ian's FIFO after an RPi to feed the AudioGD I2S to HDMI board and then feed that into your DirectStream Jr., I wonder if it will only be a fairly minor improvement over using an RPi/Allo Isolator/Kali stack. Since the Directstream already reclocks all input signals as part of the conversion to DSD AND does what appears to be a pretty good job of that, I'm not sure the improvement of the full-up Ian FIFO is worth it. Of course, I have not tried this and I could be entirely off base here. I have seen comments from those who''ve compared the 2 reclockers and found the full Ian FIFO an improvement over the Allo Isolator / Kali (of course, at a price). But those have all been in setups directly feeding DACs that do not have their own reclocking process AND did not have the I2S to HDMI between the outboard reclocker and the DAC. The process of converting the I2S to HDMI (actually LVDS over HDMI) and back adds jitter too, which to some extent will negate the benefit of the FIFO no matter which you choose.  What I'm wondering (and it IS pure speculation) is will the Directstream Jr.'s reclocking plus the added jitter of I2S to HDMI conversion mask the better I2S out of the full FIFO.

 

AND I need to be clear I don't have a personal dog in this hunt. I have units here from both Allo and Ian AND worked with them both in the past. I think they are both GREAT setups from 2 GREAT and INNOVATIVE sources that have raised digital DIY'ing to new heights. I can't recommend both setups enough!!! BUT I'm not sure Ian's FIFO will benefit your setup over the RPi / Isolator / Kali solution.

 

Sorry, another long one!

 

Greg in Mississippi

 

 

[Cornan]

On 2018-01-22 at 4:56 PM, Cornan said:

Since VAC input translates to x 1,1414 to VDC output on the single ps this class II double isolated safety transformer will probably be sufficient to power both my single ps in series (=13.6968 VDC).

 

A correction since I mixed up the numbers. The VAC input translates to roughly x 1,414 and not x 1,1414, which means roughly 16,92 VDC. 

[Cornan]

7 hours ago, Balázs said:

 

Hi all

 

I am pretty new here, finding this forum quite interesting. @Cornan allow me one question regarding your planned cascaded Stammheim 3A LT3045 config: as I remember you mentioned 12 Vac to feed with. This is 12x1.414 = appr.17 Vdc. Considering that the voltage drop of the LT3045 is very low  (260 mV) and your output goal is 12 Vdc/2A  (e.g. for your Brooklyn or whatever just staying on the safe side with 2A and definitely more than 1A) you must burn (17-12)x2=10W  Even with two identical cascaded boards it's 5W a board. Is it fine with the provided heatsinks? Cheers.

 

P.S. Actually I'm planning to mod my HDPLEX 200W to drive a Brooklyn DAC+ and 2x Mutec MC3+ USB reclockers with the help of Michael's boards  I think I definitely need something  like a pre-regulator as @sandyk suggested above at least for the Mutec's 6.3 Vdc input. 

 

 

As you can see on my previous post I have adjusted that calculation after getting a correction from @zoltan and @sandyk on this thread that you might find interesting.

The heat is my biggest concern though. I might send Michael/Stammheim a pm to get this confirmed before ordering a safety transformer for my DIY LPSU project. Remember that this is my first attempt for a DIY PSU, so I am still learning how to pull this off. I just know the type of parts I want and need to ensure that they are all up for the job.

[sandyk]

Depending on the output voltage and current required, you could probably do very well using the front end of the attached John Swenson +5V PSU design,(R Core transformer and Schottky Diodes) married to a couple of higher current LT3045 PCBs instead of the existing voltage regulator .

Don't forget to allow for the lower output voltage due to the choke after the diodes !

[Cornan]

The 12VAC safety transformer I intend to use is 4.58A. https://www.conrad.com/ce/en/product/710340/Safety-transformer-1-x-230-V-1-x-12-Vac-55-VA-458-A?ref=

I plan to set the first single ps to 13-14VDC out and the second one to 12VDC out. Brooklyn DAC requires 12VDC >1.5A to ensure power on/off sequences. Otherwise it pulls <1A playing music through streaming.

[Balázs]

8 minutes ago, sandyk said:

Depending on the output voltage and current required, you could probably do very well using the front end of the attached John Swenson +5V PSU design,(R Core transformer and Schottky Diodes) married to a couple of higher current LT3045 PCBs instead of the existing voltage regulator .

You are absolutely right and this would be one logical and easy solution to my "low voltage - high current" DC needs (6.3V/2x0.8A) . Most certainly using a 200W transformer for this is a crazy idea anyway...

However my goal is to reduce the number of units I use in my HiFi setup and I'd be happy to have one and only PSU in the chain. As most output of the HDPLEX 200W are 10A max. I could power pretty many devices if I find a solution to the heat management. I am aware of some disadvantages of a shared transformer but it's okay for my usage scenarios.

 

My HDPLEX 200W feeds the Intel NUC (19Vdc) and a network switch (5Vdc/1A). I could also use the 5-12Vdc adjustable output of the HDPLEX as some people do with a signal improvement solution like an iFi DC iPurifier or like @mourip does with an additional LT3045 card. This is not really optimal considering the high ripple noise iput signal the HDPLEX provides. For sure using a much higher quality LPSU as input like an Uptone JS-2 or a PH SR7 instead of the HDPLEX would solve the issue but I'm not lucky enough to own one of these  

[Balázs]

3 hours ago, mourip said:

Regarding the HDPlex. Am I correct in assuming that by adding the secondary regulator I am overcoming the greater ripple of the HDPlex by using it as a pre-regulator to drop down the input voltage to the 3045? I have assumed that the 3045 would make up for any lower specs in the HDPlex.

 

This was my first question to Michael/Stammheim a  couple of day ago.  Being  a lazy guy please allow me to copy/paste his answer and ask you to Google translate as our communication has been in German

"Eine interessante Frage. Zunächst würde ich behaupten, dass ein Regler das Rauschen eines anderen nicht „wegregeln“ kann. Auf der anderen Seite reagiert der LT3045 schnell auf Änderungen. Sofern das Zappeln deines Netzteils ein Problem darstellt, könnte tatsächlich eine Besserung stattfinden. Am Ende würde ich tatsächlich dazu raten, mal auszuprobieren und sich genauer am Spektrumanalyzer anzuschauen, was da genau passiert. Bitte dabei unbedingt beide Ausgänge auch exakt di gleiche Ausgangsspannung synchronisieren."

So he does't really believe in this kind of "cascaded" improvement and basically suggests using an appropraite transformer instead. 

[Balázs]

41 minutes ago, Cornan said:

The 12VAC safety transformer I intend to use is 4.58A. https://www.conrad.com/ce/en/product/710340/Safety-transformer-1-x-230-V-1-x-12-Vac-55-VA-458-A?ref=

I plan to set the first single ps to 13-14VDC out and the second one to 12VDC out. Brooklyn DAC requires 12VDC >1.5A to ensure power on/off sequences. Otherwise it pulls <1A playing music through streaming.

Michael himself mentioned 12Vac input to achieve 12 Vdc as kind of a  "limit" for his board. Now for your planned setup:

 

If you set the first to let's say 14Vdc the second should absorb 14-0.4-0.26-12 = 1.34 Vdc (0.4Vd is the drop down of the diodes according to Michael) which is in your worst case 1.34 x 1.5 A =  2W which might be still OK but probably the heatsink will make a good use.

 

The first one would look like this: 12Vac x 1.414 - 0.4 - 0.26 - 14  = 2.31 Vdc. Worst case again you should burn here 3.46W which might be a hotter case to deal with.

 

So let's say you must get rid of around 6W on two boards (if my calculation is correct) Would appreciate your feedback regarding the generated heat on the boards.

 

P.S. Interesting but Mytek suggest 12V/ 4-6A (!) for the Brooklyn and officially supports the Sbooster LPSU which happens to be 12V/3A. Sbooster also confirms your 1A without headphone usage. As I am a happy Focal Utopia user I'd be corious how this 1A improves if the balanced jack outputs of the Brooklyn are in use...

[sandyk]

59 minutes ago, Balázs said:

So he does't really believe in this kind of "cascaded" improvement and basically suggests using an appropraite transformer instead. 

 There is nothing wrong with this approach if correctly implemented. It's main advantage is to reduce the amount of heating in the main voltage regulator. It also greatly reduces the remaining ripple , so that basically, all the main regulator needs to do is output a stable output voltage . You will see this approach in the Greg Erskine (DIY Audio) designed PCB to my specifications  that I use in my DAC, for example.

It also gives the option of another different output voltage, in this case it is +9V as a LM7809 was used before the LM7805. Incidentally, this PCB design gives the option to use either Surface Mount or through hole diodes in the bridge rectifier section. R1 (330 ohm 5W) helps to ensure that both supply rails die at about the same rate on switch off, helping to reduce "plops" on switch off, as well as balancing the loads on both -VE and +VE polarities. There are also holes drilled in the PCB below R1 to help with airflow around this 5W resistor for improved cooling.

 

 The photo was taken before the heat sinks were fitted.

[Cornan]

50 minutes ago, Balázs said:

Michael himself mentioned 12Vac input to achieve 12 Vdc as kind of a  "limit" for his board. Now for your planned setup:

 

If you set the first to let's say 14Vdc the second should absorb 14-0.4-0.26-12 = 1.34 Vdc (0.4Vd is the drop down of the diodes according to Michael) which is in your worst case 1.34 x 1.5 A =  2W which might be still OK but probably the heatsink will make a good use.

 

The first one would look like this: 12Vac x 1.414 - 0.4 - 0.26 - 14  = 2.31 Vdc. Worst case again you should burn here 3.46W which might be a hotter case to deal with.

 

So let's say you must get rid of around 6W on two boards (if my calculation is correct) Would appreciate your feedback regarding the generated heat on the boards.

 

P.S. Interesting but Mytek suggest 12V/ 4-6A (!) for the Brooklyn and officially supports the Sbooster LPSU which happens to be 12V/3A. Sbooster also confirms your 1A without headphone usage. As I am a happy Focal Utopia user I'd be corious how this 1A improves if the balanced jack outputs of the Brooklyn are in use...

 

Thanks a lot @Balázs!  

This is very useful information for me. I will surely ask Michael as well if my intended PSU will be up for the job. He have already confirmed that the safety transformer will work with one single ps. I´ll just need to confirm that it will work with two in series as well without starting a fire. If I am good to go I will order the parts and start with this project in March (after my move to a new apartment in mid Feb). I will surely report back on both SQ and generated heat as soon as I have put this thing together. BTW. Do you know of a way to reduce the heat without adding pre regulation, heat sinks, thermal paste and without reducing SQ?

 

The measurement of Brooklyn DAC is the real current draw in my perticular setup. I cannot guarantee that it be true in any other setup. It needs to be tested if you use it with <1.5A. In my setup the highest figure I have got is 1,52 A during multiple powering on/off (3  sequencies) and only during a millisecond or so. Normally it is around 911-915mA during music listening via headphones or active speakers. 4-6 A or even 3A for Brooklyn DAC is most likely over the top for most setups...but ofcourse a good thing.  

[sandyk]

5 minutes ago, Cornan said:

Do you know of a way to reduce the heat without adding pre regulation and without reducing SQ?

  John Swenson's choke input approach does this. You could also drop the voltage a little more by using 2 series diodes in each leg of the bridge rectifier. (8 diodes instead of 4) Incidentally, even if you don't use a large expensive choke as John did, even using a 470uH 5A choke there instead, will help to reduce the rubbish going back into the A.C. mains, as well as reduce the voltage on the main filter cap a little too.

[Cornan]

1 hour ago, Balázs said:

 

This was my first question to Michael/Stammheim a  couple of day ago.  Being  a lazy guy please allow me to copy/paste his answer and ask you to Google translate as our communication has been in German

"Eine interessante Frage. Zunächst würde ich behaupten, dass ein Regler das Rauschen eines anderen nicht „wegregeln“ kann. Auf der anderen Seite reagiert der LT3045 schnell auf Änderungen. Sofern das Zappeln deines Netzteils ein Problem darstellt, könnte tatsächlich eine Besserung stattfinden. Am Ende würde ich tatsächlich dazu raten, mal auszuprobieren und sich genauer am Spektrumanalyzer anzuschauen, was da genau passiert. Bitte dabei unbedingt beide Ausgänge auch exakt di gleiche Ausgangsspannung synchronisieren."

So he does't really believe in this kind of "cascaded" improvement and basically suggests using an appropraite transformer instead. 

 

As I understand this answer by Google translator you are discussing two boards in parallel and not two boards in series right? This is something that even John Swenson have said it is not as a perticuluarly good idea when used on separate boardscompared to on the same PCB. Even LPS-1.2 uses parallel boards though, but my guess is that they are fitted to one PCB just like Michaels ps.

[Balázs]

6 minutes ago, sandyk said:

 There is nothing wrong with this approach if correctly implemented. It's main advantage is to reduce the amount of heating in the main voltage regulator. It also greatly reduces the remaining ripple , so that basically, all the main regulator needs to do is output a stable output voltage.

 

Cool, nice board indeed! Well, I think there are two major issues at least regarding my use case (with HDPLEX 200W):

 

1) How to achive the lowest possible ripple noise

This is a problem the HDPLEX is responsible for. Its LT1083 regulators produce a 3-20mV ripple noise and even if I am happy to see your statement that further regulator stages "greatly reduce the remaining ripple" I still believe that the better your noice level of your source is the better output quality you can get at the end of the regulator chain.  

 

2) How to reduce the amount of heating

This is a difficult one because of the very low dropdown of the LT3045 and the 200W transformer. Achieving 12Vdc like @Cornan is gonna do is feasable because the 200W transformer provides 11 Vac (even if the LT3045 might get quiet hot, but we will see) The real question is how to achieve 6.3V/2x0.8A for my two Mutecs without driving the whole box to the boiling temp.

 

Okay and the solution is... well I don't know   I dig your idea of using the LT1963 based pre-regulator with the AC source of the transformer which drops voltage significantly better than the LT3045. As this board is 1.5A I certainly should use two, one for each input of the Stammheim dual board. Maybe other two with a single Stammheim board to be on the safe side regarding the heat generation if driving the Brooklyn with 12V/1.5-2A

[Cornan]

1 minute ago, sandyk said:

  John Swenson's choke input approach does this. You could also drop the voltage a little more by using 2 series diodes in each leg of the bridge rectifier. (8 diodes instead of 4) Incidentally, even if you don't use a large expensive choke as John did, even using a 470uH 5A choke there instead, will help to reduce the rubbish going back into the A.C. mains, as well as reduce the voltage on the main filter cap a little too.

 

Great info! Thanks a lot Alex!  

Any suggestion of a good quality 470uH 5A choke to use?

[Balázs]

2 minutes ago, Cornan said:

 

As I understand this answer by Google translator you are discussing two boards in parallel and not two boards in series right? This is something that even John Swenson have said it is not as a perticuluarly good idea when used on separate boardscompared to on the same PCB. Even LPS-1.2 uses parallel boards though, but my guess is that they are fitted to one PCB just like Michaels ps.

Actually we were discussing a cascaded (in series) scenario. My question to Michael was whether it is a good idea or not to use the low quality output of the HDPLEX as input for a further regulator stage represented by his board in order to achieve an improvement in the ripple noise.

[sandyk]

1 minute ago, Cornan said:

 

Great info! Thanks a lot Alex!  

Any suggestion of a good quality 470uH 5A choke to use?

 

 Anything like that should be fine. Just make sure it is 5A, not 3A, as they use thicker gauge wire. 

The extra voltage drop will be fairly low, but the main advantage may be a quieter transformer at high current use, and less crap going back into the AC mains.

[Cornan]

Just now, Balázs said:

Actually we were discussing a cascaded (in series) scenario. My question to Michael was whether it is a good idea or not to use the low quality output of the HDPLEX as input for a further regulator stage represented by his board in order to achieve an improvement in the ripple noise.

 

Thanks for clearing that out. Bloody Google translator!  

I can only say that two of Alexeys 500mA/LT3045, two of Alexeys 1A/LT3045s or two 3A/LT3045 single ps in better in series than in singles in my setup. I am using Gophert csp-3205II (floating SMPS 0-32V/5.1A max) on all spots, so I would´nt know how HDPLEX compares.

[Balázs]

22 minutes ago, sandyk said:

  John Swenson's choke input approach does this. You could also drop the voltage a little more by using 2 series diodes in each leg of the bridge rectifier. (8 diodes instead of 4) Incidentally, even if you don't use a large expensive choke as John did, even using a 470uH 5A choke there instead, will help to reduce the rubbish going back into the A.C. mains, as well as reduce the voltage on the main filter cap a little too.

Interesting. Certainly you can drop voltages by cascading as many bridge rectifiers as possible. The choke is also a great idea but the drop would be low. So let's be more specific on my issue:

 

Given a 12VAC input what is the best way to achieve a good quality (low ripple noise) 6.3V/1.6V DC signal without burning a hole in the floor?

 

P.S. @sandyk 's above solutions with both the choke and additional diodes would certainly work great in the 12VAC to 12DC/1.5A scenario (e.g. driving @Cornan's Brooklyn) to get rid of some input voltage and make the LT3045 a bit cooler. I wouldn't think they're good enough for 6.3V destination.  

[sandyk]

 

I would use my original suggestion of a LT1963 PCB as it has a fairly low noise level and a reasonable sized heatsink.

Try the mods I have suggested too, as this will drop a little more voltage. The added 100uF could be mounted under the PCB

 

 

Unable to remove previously added schematics or drawings !!! 

[Balázs]

51 minutes ago, Cornan said:

 

Thanks for clearing that out. Bloody Google translator!  

I can only say that two of Alexeys 500mA/LT3045, two of Alexeys 1A/LT3045s or two 3A/LT3045 single ps in better in series than in singles in my setup. I am using Gophert csp-3205II (floating SMPS 0-32V/5.1A max) on all spots, so I would´nt know how HDPLEX compares.

Yeah , Google translator is a strange animal to deal with

 

I've just checked your Gophert (http://www.gophertc.com/en/cps-3205) and ripple noise is <=30mV This puts this device into the same category where the HDPLEX sits or even slightly worse (sorry to say that)

 

To be clear on that: I am NOT saying that using a decent DC output of a HDPLEX or a Gophert as input for a LT3045 board is a bad idea especially that both you and @mourip seem to be happy with the result. I simply assume that using an EVEN BETTER quality signal with lower noise rate would result better quality end result. This "better quality" DC signal might be from an excellent LPSU (like I mentioned before) or from a better quality pre-regulator (by skipping/bridging the built-in ones in the HDPLEX or Gophert). The latter one is what I'm trying to build.

 

I strongly believe that changing your current setup from the Gophert to a transformer fed one you will once again be able to hear some SQ improvement.

 

Using more LT3045 in a chain is cool. First because you 've experienced better SQ obviously but also second because it drops more voltages. Not much more though. Definitely benefical for the Brooklyn scenario. Not a big deal for the two Mutecs unfortunately (besides SQ of course).

[Cornan]

4 minutes ago, Balázs said:

Yeah , Google translator is a strange animal to deal with

 

I've just checked your Gophert (http://www.gophertc.com/en/cps-3205) and ripple noise is <=30mV This puts this device into the same category where the HDPLEX sits or even slightly worse (sorry to say that)

 

To be clear on that: I am NOT saying that using a decent DC output of a HDPLEX or a Gophert as input for a LT3045 board is a bad idea especially that both you and @mourip seem to be happy with the result. I simply assume that using an EVEN BETTER quality signal with lower noise rate would result better quality end result. This "better quality" DC signal might be from an excellent LPSU (like I mentioned before) or from a better quality pre-regulator (by skipping/bridging the built-in ones in the HDPLEX or Gophert). The latter one is what I'm trying to build.

 

I totally agree that a better PSU surely will improve the end result. No doubt! However, there is much more to it than ripple noise to get a great end result. Gophert is a floating type of SMPS. It is connected to a DC blockertrap filter> balanced and floating IT via a star-earthed and starquad wired PSD. I use starquad AC & DC cables. All these things matter too! 

My plan with DIY LPSU is however to find out if this scenario will improve if I skip out the Gophert all together and go safety transformer into single ps´s? I will not comment any changes SQ until I have actually heard it using the DIY LPSU with the very same conditions, even if I know what I beleive.  

[Balázs]

42 minutes ago, sandyk said:

 

I would use my original suggestion of a LT1963 PCB as it has a fairly low noise level and a reasonable sized heatsink.

Try the mods I have suggested too, as this will drop a little more voltage. The added 100uF could be mounted under the PCB

Excellent, thank you so much. I wish the LT1963 had a wider range of frequency for its nice <40uV noise reduction like the LT3045 has. But it's a minor issue - if an issue at all

 

So I'd use two LT1963 PCBs to reach the 1.6-2A need of the two Mutecs. If the 12V/1.5A would be too hot for the Brooklyn an other pair of LT1963 PCBs would be used in that part, too.

[Balázs]

22 minutes ago, Cornan said:

All these things matter too! 

 

 

Of course they do. And yes hearing is believing

 

I tell you what:  I own both the HDPLEX and an SBooster BOTW 12V.  Driving the Brooklyn with both of them I experience an audible difference between the two - the Sbooster is so much better (and no I do not work for Sbooster  ). The discussed modifications might change this result.