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What Shunyata and Furman (SMP) Have in common - Inductance!

Hi everyone,

I've been doing a little online research. The name that seems to come across here on audiogon regarding power conditioners is Shunyata, while @elizabeth and I talk Furman, especially due to cost.


I wanted to point out that what these two brands have in common is inductance. Coils. Coils in series with the outputs.


Furman and others who have licensed series mode surge protectors use great big coils to slow down surges long enough to let the surge protector react. Furman calls it SMP, but the tech has also been licensed to PS Audio and other makers. Essentially this is a low pass filter, which starts working at 3 kHz. That's way down in the audible range.


It's clear from pics of Shunyata's insides that they are using great big coils too. Why? Well, you can make a coil with high inductance, and low resistance at AC.


Anyway, my point is, these two brands share this basic principle. If you want to supplement a Shunyata by taking digital streaming outside of it (routers, wifi, etc) consider this super inexpensive Furman strip:

https://amzn.to/2U9QiiR

It's also a great starter conditioner, and the series surge suppression is unbeatable. Furman also has LiFT which I trust works but I've not investigated it very much. Furman makes a boatload of devices, so check for SMP and LiFT for the best noise suppression.

The PS Audio strip which uses series suppression is here:

https://www.psaudio.com/products/dectet-power-center/


Of course, saying these conditioners have the same principle is not the same as saying they work equally well or are best for your application. To your own ears be true!


Best,

E
erik_squires

Showing 14 responses by erik_squires

erik_squires OP
16,468 posts
 
Hi Sadano,
Feel free to tag me all you want, but I'm not obligated to read or respond to you. You've never been civil, and I choose to ignore you now.

Just wanted to do the decent thing and let you know. I've barely read your posts. Feel free to spew, but it makes no difference to me.

Best,

Erik
erik_squires OP
16,468 posts
 
Really need to delete this thread, as the PS Audio units I linked to are no longer the same ones. Those seem to be gone.
erik_squires OP
16,468 posts
 
I am not a dealer. Unfortunately I cannot edit a discussion once it has been replied to, and being sure I don't use an affiliate link is also complicated, but here it is:
https://www.amazon.com/Furman-Aluminum-8-Outlet-Protection-Conditioning/dp/B000YYVLAK/ref=sr_1_1_ssp...=
I'll keep that in mind for future posts.
erik_squires OP
16,468 posts
 
I suggest if you don’t like my blog you go write your own.

That's kind of how the Internet works.


Erik


erik_squires OP
16,468 posts
 
Your own link :
https://www.mixonline.com/technology/furman-sound-implement-smp-technology-381312
basically is spec for spec identical to the description of the multi-stage protection described by Brickwall. Down to the clamping voltages. Now stop
erik_squires OP
16,468 posts
 
You can’t lump all Furman products together anymore than you can McIntosh and PS Audio. Some use series mode protection, and some use plain old MOVs.  You are misreading the article if you think that all Furman surge suppressors use MOV's. That's' not what they mean to say. They mean to say they sell products with a variety of features.

The products Furman labels as SMP are clearly series mode, non sacrificial components. I make that clear in my blog post that this is the key feature.


PS Audio constantly changes it’s product line. Based on their current web products it’s not clear if they are using series mode protection or not. It was clear in models no longer available on their web site.


Inductance is not good for transparent sound quality. It reduces current and rolls off the highs.

Only if you don’t know how to do AC analysis properly. If you believe this is universally true then you should be advocating the end to all linear power supplies.


Also, hard to tell if you like inductance or not. You seem to say that SurgeX is better than a Furman because they use MORE inductance, but then also want to take the position that all inductance is bad. Have to pick a side here.


Furman also ads LiFT to the strips I recommend, further lowering the noise floor, without adding inductance. That makes them better than a SurgeX, right??

erik_squires OP
16,468 posts
 
Hi Sadono,

As far as I know, the license/patent comes from Jack R. Harford / Electronic Systems Protection. Please post a link to any legal documents / reporting regarding licensing issues with Furman.


https://patents.google.com/patent/US4870528A/en

You are completely wrong about Furman SMP using MOV's, I've disassembled them. They do not use MOVs and they are very good. Please see their spec sheet.


https://www.furmanpower.com/furman-technologies/series-multi-stage-protection

In addition to Furman, SurgeX and Brick Wall, the other licensees I know of are PS Audio and McIntosh. Among those, McIntosh charges the most, followed by SurgeX for the same basic technology.  Furman is the most affordable in their $180 power strips.

In regards to Chang, I stand corrected, Chang advertises no coils in their tech. How pathetic, since that essentially means they can't block anything below RFI. Also, their claims are questionable. A well designed coil is a good thing, with no lag, unless you are a surge.   Please go spend tens of thousands of dollars on their gear if that makes you happy.

Best,
Erik
erik_squires OP
16,468 posts
 
@ptss If you use a coaxial cable into the home, consider a coax ground loop isolator.


They work great to remove ground loops, and sometimes (but not always) can clean up DAC's too. :) They're super cheap, like $20 or so. 

Sometimes a ground loop makes it into the digital pathways (unless you use optical) and this can help.



erik_squires OP
16,468 posts
 
@ptss I recommend a balanced approach.
Good acoustics first.

I also recommend, if you are concerned, keeping noise creating power supplies (switching wall warts) outside your clean power zone. It is convenient to use a conditioner with mulitple, isolated power banks.


If you don't have something like that, a Furman strip for your routers, streamers, etc. will keep that on the dirty side, and put an extra layer of AC filtering between your analog / linear gear and it.


Use inexpensive but shielded power cables.

Best,
E
erik_squires OP
16,468 posts
 
P.S. I just looked at a lot of pictures of the Chang units. Sure looks like they use a lot of coils to me!



erik_squires OP
16,468 posts
 
$1,300 is about 10x the cost of the basic Furman strip.


Glad you are happy, but that is most definitely out of my price range.

Best
E
erik_squires OP
16,468 posts
 
Hi @don_c55 You make a good argument, no I have not. Care to send me one? :)

Best,
E
erik_squires OP
16,468 posts
 
No matter how big the coil inductance is, there still will be a small amount of sound smearing due to lag.



Show your work.  The idea that lag in the power supply = smearing of audio needs more validation.


erik_squires OP
16,468 posts
 
Coils cause a time lag in the drawing of AC into the equipment!


With a high enough L, XL drops to near zero and therefore the difference between current and voltage goes to zero as well.

Best,
E

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