My Computer Builder Is Disputing Need For LPSU....

[Evo-No-Revo]

I am having a person that is known in the computer building world build my computer. I don't really want to name the individual.

 

But I am having him build a hot rod PC for Audio/Video playback. I am using a MicroRendu but building for USB and I2S playback as well. I will be running JRiver, Roon and HQP.

 

I have purchased one of the new HDPLEX 400W ATX Linear Power Supply. It will be delivered this week.

 

I also already have an Uptone JS 2 to run the Pink Faun I2S card and SOTM USB card.

 

This has created a bit of a stress in me as I am nothing more than a consumer of audiophile computers. I am not an engineer or IT guy.

 

Here are the comments of my computer builder:

 

"I would not use a external ATX PS, the voltage loss with the long wires will cause problems with the MB and the noise pick-up from all those wires will far outweigh and supposed noise loss from the "linear" PS."

 

"PS - Voltage loss and EMI are the laws of electronics -not opinion. I don't see any detail on the wires being used (HDPLEX 400W ATX), they would all have to be twisted and shielded and larger in size to make up for the added length."

 

 

Larry of HDPLEX response:

 

"He is correct that long wire will cause voltage loss. Some of my customers encounter this issue in the previous generation.

 

The two major upgrades for the 400w is to elimnate EMI/RFI pollution from AC grid by adding 2nd order EMI/RFI filter and adding a ELNA cap bank to compensate the potential voltage loss from the ATX cable."

 

Computer builder's response:

 

"Adding a filter to reduce the noise that having excessively long external wires causes is like placing a oil pan under a oil leak instead of eliminating the leak."

 

This is what my computer builder is recommending:

 

CORSAIR AX Series AX760 760W 80 PLUS PLATINUM Haswell Ready Full Modular ATX12V & EPS12V SLI and Crossfire Ready Power Supply-Newegg.com

 

 

I am finding it a little disturbing in finalizing my specs for the build. I don't have the knowledge to discuss this with any authority.

 

Is this an ongoing disagreement to be ignored....or something to consider? I certainly would love to not have as many boxes but I want the best possible setup as well. I always just figured the LPSU was the way to go.

 

Thanks for you input!

[wgscott]

Sounds like the computer builder doesn't buy into the audiophile mythology. This is where having some objective measurements or something that could demonstrate improvement might really help, but the same people advocating these tweaks claim that the sonic improvement isn't something you can measure.

 

Having said that, you should be able to have your computer built however suits you, just the same way as your auto mechanic doesn't get to decide what car you buy.

[Evo-No-Revo]

Thanks for your reply. I do understand the back and forth between measurements, perceived benefits, psychacoustics.

He is gladly building it the way I am requesting. But I like many just assume that LPSU is the way to go. I was hoping to see how significant his position is from people that have looked deeper into this.

I am also wanting to get a custom length, made of silver wiring harness built after I receive the unit. It will arrive with the stock HDPLEX wiring harness.

[Jean]

Thanks for your reply. I do understand the back and forth between measurements, perceived benefits, psychacoustics.

He is gladly building it the way I am requesting. But I like many just assume that LPSU is the way to go. I was hoping to see how significant his position is from people that have looked deeper into this.

I am also wanting to get a custom length, made of silver wiring harness built after I receive the unit. It will arrive with the stock HDPLEX wiring harness.

From my personal experience, I think it pays to be safe and listen to your computer builder. Unfortunately, computers have a lot of key parts that are vulnerable to electrical disturbances; motherboards and processors to are the big 2, and a severe enough electrical disturbance could fry either one.

 

You can always clean out any nasty electricity from the chain once the signal has left your PC or use something like the VBUS2.

 

My PC is never plugged directly into the wall, always into an UPC. I take a lot of precautions with my PC since PCs have a lot of time, energy and money invested in them.

 

Sent from my HTC One M9 using Computer Audiophile mobile app

[YashN]

The computer builder here doesn't understand your wish of building a computer for audiophile purposes.

 

Interestingly, HD Plex isn't mentioning another huge advantage of the Linear PSU, which is that it will not have the Leakage Currents of the default ATX switching PSUs.

 

So, my advice is to forget convincing your computer builder, but you will still need to try out the HD Plex and check whether there isn't any issue powering up the system.

 

This means that what then remains is to find someone else to do the final integration if your computer builder is reluctant and if you can't do it.

 

Should be easy enough to find someone else.

[YashN]

This is what my computer builder is recommending:

CORSAIR AX Series AX760 760W 80 PLUS PLATINUM Haswell Ready Full Modular ATX12V & EPS12V SLI and Crossfire Ready Power Supply-Newegg.com

 

 

Don't buy this.

 

I always just figured the LPSU was the way to go.

 

Yes.

Keep pushing for what you want: you're the one buying.

[Ralf11]

have build it both ways - then take the 2 computers and do a listening test - sell the one that sounds worse

 

or... flip a coin

[YashN]

have build it both ways - then take the 2 computers and do a listening test - sell the one that sounds worse

or... flip a coin

 

Less expensive: let the Computer Builder incorporate the normal ATX PSU.

 

Buy the HD Plex, and get HD Plex to help configure and install the Linear PSU.

[Evo-No-Revo]

Like I said, he is all good building it the way I want.

 

He totally knows it is for audiophile purposes. He sells SOTM so he isn't outside of the audiophile arena.

 

I just wanted some input before I approve the final build specs.

 

I will be going with the HDPLEX 400 ATX as planned.

 

Thanks

[YashN]

Like I said, he is all good building it the way I want.

I will be going with the HDPLEX 400 ATX as planned.

 

OK, sounds like you're all sorted.

[Nikhil]

I am one of the few on here who prefer the sound without an LPS in my Audio Computer. I found the sound "slow" with the LPS. Instead I choose to filter the power cord connection to the SMPS with an AC Filter from Array Solutions. To me the sound is quick and immediate in this manner with an SMPS.

 

AC Filter: https://www.arraysolutions.com/ac-7b

 

The Array AC filter is a product from the ham radio field and is great for RFI sensitive environments. Works great on TVs as well.

 

As always go with what your ears like best.

 

Regards.

[Evo-No-Revo]

I am one of the few on here who prefer the sound without an LPS in my Audio Computer. I found the sound "slow" with the LPS. Instead I choose to filter the power cord connection to the SMPS with an AC Filter from Array Solutions. To me the sound is quick and immediate in this manner with an SMPS.

 

AC Filter: https://www.arraysolutions.com/ac-7b

 

The Array AC filter is a product from the ham radio field and is great for RFI sensitive environments. Works great on TVs as well.

 

As always go with what your ears like best.

 

Regards.

 

Hmmm, that is interesting idea.

 

Do you have any perception of a lower noise floor when compared to a LPSU?

[EuroChamp]

It would be best to compare these two power supplies. Compare them on you own computer - and measure the noise directly on the mainboard connector.

 

I did that and ended up with the shortest possible wires together with some ultrafast capacitors from Panasonic and Wima. They lower the riple significantly.

But my solution is not plug and play.

 

What I know for sure, long cable and additional connectors in between are not to prefer.

 

And don't forget to listen and compare.

 

 

Sent from my iPad using Computer Audiophile

[internethandle]

If you're going to go with a SMPS, I'd go with a EVGA Platinum 80+ model over the Corsair (such as this one, which I currently use: EVGA - Products - EVGA SuperNOVA 650 P2 Power Supply - 220-P2-0650-X1) due to their ultra-low ripple specs and usage of high quality Nippon caps. While the Corsair is likely very good in build quality, EVGA uses, as their OEM manufacturer, Leadex, who currently have the lowest ripple supplies in a market full of relatively low ripple supplies (this is a somewhat new consideration for ATX SMPS PSU manufacturers is my understanding, and Leadex sort of led the charge). Even at full load these supplies won't break 8 mV or so on most rails - there's even further ripple suppression in the ATX cable loom, with a Nippon cap toward the end of the 24-pin cable, for instance. Comparatively, a quick Google search reveals the recommended Corsair supply tops out around 28mV full load, which isn't bad at all in "real world" applications, but again, we're talking about an audio PC, so quieter the better would seem to be the correct ethos. Also, the EVGA supply's fan does not activate unless a certain load is exceeded, which in a dedicated audio PC essentially means that it is silent given that, typically, there isn't anything too intensive being done during playback. Ripple is not everything when it comes to noise (LPSU's should still, even with sometimes higher ripple, be less "noisy"), but it's helpful, and a lot cheaper than getting a boutique audiophile ATX LPSU. If cost is not an issue, I tend to simply be skeptical of these LPSU supplies - anecdotal reports of their malfunctioning lend a quality of their respective manufacturers still working out the kinks, which is fine, this is a very nascent and not very well populated market, but given the high cost and potential risk, I went with the EVGA supply for my mobo and LPSU for my USB card and, maybe in the future, my drives.

[Nikhil]

Do you have any perception of a lower noise floor when compared to a LPSU?

 

I would have to go back to an LPS to check but I don't remember noticing a difference.

For me - I just preferred the sound without the LPS.

[bibo01]

If you're going to go with a SMPS, I'd go with a EVGA Platinum 80+ model over the Corsair (such as this one, which I currently use: EVGA - Products - EVGA SuperNOVA 650 P2 Power Supply - 220-P2-0650-X1) due to their ultra-low ripple specs and usage of high quality Nippon caps. While the Corsair is likely very good in build quality, EVGA uses, as their OEM manufacturer, Leadex, who currently have the lowest ripple supplies in a market full of relatively low ripple supplies (this is a somewhat new consideration for ATX SMPS PSU manufacturers is my understanding, and Leadex sort of led the charge). Even at full load these supplies won't break 8 mV or so on most rails - there's even further ripple suppression in the ATX cable loom, with a Nippon cap toward the end of the 24-pin cable, for instance. Comparatively, a quick Google search reveals the recommended Corsair supply tops out around 28mV full load, which isn't bad at all in "real world" applications, but again, we're talking about an audio PC, so quieter the better would seem to be the correct ethos. Also, the EVGA supply's fan does not activate unless a certain load is exceeded, which in a dedicated audio PC essentially means that it is silent given that, typically, there isn't anything too intensive being done during playback. Ripple is not everything when it comes to noise (LPSU's should still, even with sometimes higher ripple, be less "noisy"), but it's helpful, and a lot cheaper than getting a boutique audiophile ATX LPSU. If cost is not an issue, I tend to simply be skeptical of these LPSU supplies - anecdotal reports of their malfunctioning lend a quality of their respective manufacturers still working out the kinks, which is fine, this is a very nascent and not very well populated market, but given the high cost and potential risk, I went with the EVGA supply for my mobo and LPSU for my USB card and, maybe in the future, my drives.

 

You can compare the tests of your psu with Corsair RM550X (or RM750X) which is a better version than AX760 originally suggested.

 

I am one of the few on here who prefer the sound without an LPS in my Audio Computer. I found the sound "slow" with the LPS. Instead I choose to filter the power cord connection to the SMPS with an AC Filter from Array Solutions. To me the sound is quick and immediate in this manner with an SMPS.

 

AC Filter: https://www.arraysolutions.com/ac-7b

 

The Array AC filter is a product from the ham radio field and is great for RFI sensitive environments. Works great on TVs as well.

 

As always go with what your ears like best.

 

Regards.

It is also possible to employ top EMC/EMI filter by Shaffner (look for "B" version for medical application).

[Audio_ELF]

Off topic but ...

Having said that, [...] your auto mechanic doesn't get to decide what car you buy.

That maybe true Bill ... but I've known a few mechanics who weren't above "I told you so" comments after you bought the one they recommended against. :-)

[bibo01]

You can compare the tests of your psu with Corsair RM550X (or RM750X) which is a better version than AX760 originally suggested.

 

...

Just a follow up....

The RM model is not Corsair flagship, but the new version with new capacitors is plenty good in testing conditions for our requirements and cheaper.

[Cebolla]

Off topic but ...

That maybe true Bill ... but I've known a few mechanics who weren't above "I told you so" comments after you bought the one they recommended against. :-)

Plus the inevitable suck in of breath between teeth, followed by "It'll cost ya" and reeling off of that long list of 'necessary' fixes.

[blownsi]

Since your builder sells SOTM I'm guessing this isn't the first time he's heard of an LPS for a audio computer. Have you asked him why he recommends not using one? Perhaps he has tested both or heard from other customers. If he's simply trying to save you money then tell him thanks but you would prefer to spend the extra just in case it makes a difference.

[YashN]

Since your builder sells SOTM I'm guessing this isn't the first time he's heard of an LPS for a audio computer.

 

He might know something about SOTM products, but that doesn't mean he knows something about audiophile power supplies for computers.

 

How exactly do the filters and other SMPS ATX PSUs mentioned above tackle Leakage Currents?

[Pepsican]

He might know something about SOTM products, but that doesn't mean he knows something about audiophile power supplies for computers.

 

How exactly do the filters and other SMPS ATX PSUs mentioned above tackle Leakage Currents?

The recommended AX760 is a bog standard ATX supply. It does nothing special and the design is already a few years old. I have one in my PC.

[bibo01]

...

 

How exactly do the filters and other SMPS ATX PSUs mentioned above tackle Leakage Currents?

The filters I have recommended ("B" revision) have extremely low leakage.

[wgscott]

Off topic but ...

That maybe true Bill ... but I've known a few mechanics who weren't above "I told you so" comments after you bought the one they recommended against. :-)

 

If I were an auto mechanic, that would be me.

[lmitche]

If you're going to go with a SMPS, I'd go with a EVGA Platinum 80+ model over the Corsair (such as this one, which I currently use: EVGA - Products - EVGA SuperNOVA 650 P2 Power Supply - 220-P2-0650-X1) due to their ultra-low ripple specs and usage of high quality Nippon caps. While the Corsair is likely very good in build quality, EVGA uses, as their OEM manufacturer, Leadex, who currently have the lowest ripple supplies in a market full of relatively low ripple supplies (this is a somewhat new consideration for ATX SMPS PSU manufacturers is my understanding, and Leadex sort of led the charge). Even at full load these supplies won't break 8 mV or so on most rails - there's even further ripple suppression in the ATX cable loom, with a Nippon cap toward the end of the 24-pin cable, for instance. Comparatively, a quick Google search reveals the recommended Corsair supply tops out around 28mV full load, which isn't bad at all in "real world" applications, but again, we're talking about an audio PC, so quieter the better would seem to be the correct ethos. Also, the EVGA supply's fan does not activate unless a certain load is exceeded, which in a dedicated audio PC essentially means that it is silent given that, typically, there isn't anything too intensive being done during playback. Ripple is not everything when it comes to noise (LPSU's should still, even with sometimes higher ripple, be less "noisy"), but it's helpful, and a lot cheaper than getting a boutique audiophile ATX LPSU. If cost is not an issue, I tend to simply be skeptical of these LPSU supplies - anecdotal reports of their malfunctioning lend a quality of their respective manufacturers still working out the kinks, which is fine, this is a very nascent and not very well populated market, but given the high cost and potential risk, I went with the EVGA supply for my mobo and LPSU for my USB card and, maybe in the future, my drives.

Why not the titanium model? It just got a killer review on anandtech, or was it tomshardware? The ripple specs and efficiency are amazing.

 

I'm using the 1600 watt evga titanium here. Total overkill but it sounds great. The lower wattage models were not available at my time of purchase.

 

It's plugged into an isolation transformer with a floating neutral secondary to keep the switch mode nasties out the rest of the system.