# In-Depth Review: Furman Power Factor Pro (conditioner)



## Ferbose

Recently I acquired the Furman Power Factor Pro ($230) for my system. So far it seems to make every piece of equipment I plug into it sound better, and hence I thought I would share some of my experience with it with other head-fiers. Admittedly, it is pretty hard to evaluate the sonic effects of a power conditioner. Since I have owned it for several months and did quite a few critical comparisons using it, and did a little scientific experiment myself. I now feel confident to report that it does bring audible sonic benefits to source components and amps in my system. 

For Amps

 Among all the evaluations I have made, one particular test clearly showed me the sonic benefits of this conditioner. This was a four-way amp shoot-out, and one of the amps (Jolida JD301) was plugged into Furman conditioner or a Belkin surge protector ($40). A more expensive, modified Jolida JD102 ($950) was also in the shoot-out. When both were connected to Furman, the cheaper JD301 sounded better than JD102 with manufacturer-suggested bias setting. When JD102 was switched to Belkin, it sounds worse than JD102 with Furman. The details of the shoot-out is in this thread. Through this test, I realized that the benefit of Furman conditioner is on the same scale as an amp upgrade. But I am talking about budget amps under $1k which don’t have the greatest power supply, which may not apply to more expensive amps. 

 I have also compared Furman to the wall outlet using other several tube amps, and I always prefer using the Furman. Furman does not seem to change tonal balance, but makes treble smoother, background quieter and increases details. In my system, more expensive amps seem to benefit less from plugging into Furman, which may indicate that they have better power supply sections to begin with.

For Sources

 Every now and then I also like to compare CD playback using my Sony DVP-NS900V ($1k) DVD/SACD player’s internal D/A versus my Benchmark DAC1, mainly to convince myself that DAC1 is a worthwhile investment. Fortunately, DAC1 outperforms my SACD player in quite a few ways like details, imaging, ambience and bass impact, when both are plugged into Belkin. For this I am able to use the input switch on my amp or an input switch box to do quick A/B. Plugging both into Furman, the differences become so tiny that I almost considered selling my beloved DAC1. Although both units benefit from using Furman, Sony gets more sonic improvement than DAC1, probably because it has a weaker internal power supply (which is kind of obvious by looking at the power transformer inside). From such comparisons I learned that power supply quality can really affect a source component’s sonic performance. Even at $1k level, power supply is probably still not perfect and a conditioner can still help. 

A Scientific Test

 A more scientific demonstration of the Furman conditioner’s function happened in my research lab. In my university lab we have an extremely sensitive amplifier for measuring minute ionic currents through the pore of a single protein (picoampere range). Of course, it still has some self-noise, which is visualized by connecting the output to an oscilloscope. When this $4k amplifier is plugged into Furman versus a cheap power strip, the noise floor is reduced, judging from the traces on the oscilloscope. Since our amplifier had state-of-the-art sensitivity just a few years ago, I believe it has an excellent power supply section in it. Undeniably, Furman conditioner helps lower its noise, as _seen_ by me and a fellow scientist. 

 Now my SACD player, DAC1, head amp, and speaker amp are all plugged into Furman Power Factor Pro, because I actually hear sonic improvements—subtle, but significant. It is like getting four components upgraded at the same time, for a small price of $230. To be honest, I would be willing to pay $200 to upgrade any of the four components for a clearly audible difference. Also, Furman Power Factor Pro is supposed to provide superior surge protection, which is more easily measured in a lab than sonic benefits. Furman is a major manufacturer of pro-audio power conditioning devices. So I trust them on their claims of surge protection (less snake-oil in pro-audio). For the sonic benefits of course I need to hear it for myself. Its voltage indicator is pretty useful, too, since I can see for myself if my house’s AC voltage is too high, too low or fluctuating too much. 

Why does it work?

 If something brings audible sonic benefits, I want to know why. I am not a power expert but I can share what I have learned about power conditioning through on-line research. Theoretically, power conditioning is a good thing. AC lines generally are polluted by RF (radio frequency pickup) and EMI (caused by other appliances). Filtering out such noises or regenerating AC using batteries or amplifiers should bring sonic benefits. In reality, it is not uncommon for power conditioners to degrade the sonic performances of audio components. From I have read, there are two types of common problems in power conditioners. First is that it may leak noise to the ground, and any equipment that uses the ground voltage as a reference can be affected. Second, the electronic circuit in the conditioner may raise AC impedance. Higher AC impedance means the amplifier will get less instantaneous current when the current demand is high. In fact, quite a few head-fiers posted that they prefer having source components plugged into conditioners but not amps. They think source components gain resolution, but amps lose dynamics. This appears to me as an AC impedance problem. House outlet AC impedance in North America is generally 0.2 ohms or higher, and a 6-feet, 18-AWG standard power cable has 0.05 ohms of impedance. Outlet AC impedance significantly increases when power-hungry appliances (heaters, A/C, overs, refrigerators) are operating, and not just in your house but all your neighbors who share the same main AC line. Furman Power Factor Pro actually lowers AC impedance and stores energy to provide 45 amps of instantaneous current upon demand. To me, it seems like lowering AC impedance using a conditioner is more useful than using heavier gauge power cables, since a standard power cable does not contribute much to AC impedance in the first place. 

 According to the product description, Power Factor Pro does not leak noise to ground and lowers AC impedance using inductors to store energy, which address two of the common problems associated with power conditioners. In addition, Power Factor Pro boasts an extremely level of noise attenuation in the audio band (From the datasheet: 40 dB at 100kHz, 40 dB at 100 kHz, 100 dB at 10 MHz). Most other conditioners I have seen have at most 6-10 dB filtering at 10 kHz. 

Conclusion

 In the end, all the impressive product specs don’t mean a thing if there is no sonic improvement to the ear. To my ears, I have heard Power Factor Pro improving the sound of all components I have plugged into it over several months, including source and amplification devices, although I admit that human hearing is a finicky thing. With my eyes, I have seen it lowering the noise level of a hi-end ($4k) scientific instrument amplifier via the oscilloscope. Additionally, Furman is able to present a really good explanation of why their new conditioner is specially designed to make amps sound better, an explanation that makes technical sense to me and not some snake oil. This is why I am sold and hence enthusiastically recommend this inexpensive ($230) conditioner for those who want to play with power treatment. Unfortunately, I don't have another good power conditioner for comparison. 

 I don’t think it is a coincident that Furman can produce a power conditioner that actually works well. Furman has been in pro-audio business for many years and has a good reputation, and I don’t think that’s a result of voodoo and aggressive marketing. Of course, for sonic improvements, your mileage may vary, but at least it will provide really good protection for your pricey gears. Highly recommended!


----------



## Joey_V

Good review!

 This is exactly why I will be getting the Belkin PureAV power conditioner and filter.

 Here is a pic of the one I want:
http://catalog.belkin.com/PureAV_det...duct_Id=178914






 Here is the PureAV lineup.. they look and perform spiffy.
http://catalog.belkin.com/PureAV.pro...tion_Id=202493

 Thanks Febose, you and other reviewers have helped me push towards my own power console.


----------



## Welly Wu

That was a good write up Ferbose. At least you did the right thing and you decided to get the Furman power conditioner _after you had your reference system settled and knew it well_. One recommendation for all of you who are interested in getting a power conditioner: make sure you have a reference system established and you know its sound very well. Then, make sure that you do your homework on power conditioners because they are not all built the same and a good number of cheaper ones actually introduce more problems than solve them (i.e., the two major problems cited by Ferbose in his write up). Otherwise, they are for real in terms of offering sonic and video performance improvements. Lastly, modifying a power conditioner, especially when it is done my the same manufacturer, can yield incredible performance improvements such as greater definition, clarity, immediacy, bass tightening and extension, along with other audio criteria -- only after you have lived with the stock power conditioner for several months so you can make a quasi objective analysis of the before and after results. I can attest to this.


----------



## Ferbose

Quote:


  Originally Posted by *Welly Wu* 
_ Lastly, modifying a power conditioner, especially when it is done my the same manufacturer, can yield incredible performance improvements such as greater definition, clarity, immediacy, bass tightening and extension, along with other audio criteria -- only after you have lived with the stock power conditioner for several months so you can make a quasi objective analysis of the before and after results. I can attest to this._

 

Modifying a power conditioner--is that dangerous?
 How do you modify a power conditioner?


----------



## Welly Wu

YOU do NOT modify any power electrical system. Ask your manufacturer if he is willing to do so at your request. However, I doubt Furman will even contemplate such an act.


----------



## Ferbose

Another interesting conditioner I have seen is APC's H-series voltage regulators for home theater: http://www.audioholics.com/news/pres...nditioners.php

 It actively clamps output voltage at 120V, which is probably better than just noise filtering, _in theory_.


----------



## bhd812

I have been looking for a power conditioner on top of my deicated line for just my two mono block speaker amps (all my front end audio has a bpt bp-1).

 I was looking at some for the $200 range and I think this may be the catcher.. What I need other then good sonic improvement (one that I actually like long term) is a volt read out cause I need to see if the a/c is doing. I think this is important in power amps cause they are the suckers of power.

 Of course I really would like a digital read out meter but one in the $200 range and with actual improvements is hard to find.


 When you seen the volt read out on this unit how much did it go up and down?
 Did it stay most at this or that? or did it go up and down alot?
 when it did go up and down what did you do? did you hear a sonic change or does the unit correct like some monster power centers do?

 great review~! I usually dont like reading reviews but this one kept my interest..thank you


----------



## Ferbose

Quote:


  Originally Posted by *bhd812* 
_I have been looking for a power conditioner on top of my deicated line for just my two mono block speaker amps (all my front end audio has a bpt bp-1).

 I was looking at some for the $200 range and I think this may be the catcher.. What I need other then good sonic improvement (one that I actually like long term) is a volt read out cause I need to see if the a/c is doing. I think this is important in power amps cause they are the suckers of power.

 Of course I really would like a digital read out meter but one in the $200 range and with actual improvements is hard to find.


 When you seen the volt read out on this unit how much did it go up and down?
 Did it stay most at this or that? or did it go up and down alot?
 when it did go up and down what did you do? did you hear a sonic change or does the unit correct like some monster power centers do?

 great review~! I usually dont like reading reviews but this one kept my interest..thank you_

 

The voltage readout is by a row of indicator lights, each separated by 2 volts. My house AC sometimes fluctuates within 2 volts every 5-10 seconds, and sometimes stays constant for hours. This kind of slow fluctuation is not alarming, I think. Most electronic equipment in US is designed to work with 110/120V, which means it will run happily at 115V as well. The actual detrimental AC noises are in the audio band and above, which is too fast for any simple voltage indicator to follow. Unless the house AC is below 110V or above 125V, I would not be concerned. 

 Better conditioners hold AC voltage constant using active circuits to clamp it. This is theoretically better than just filtering out the noise. But my concern is how much noise is generated by the clamping circuits themselves, and how audible these noises will be. Some power conditioners claim to regenerate AC using amplifiers and even modulate AC frequency, and again this sounds fancy but I don't know if it will bring sonic benefits or degradation.


----------



## Edwood

Quote:


  Originally Posted by *Joey_V* 
_Good review!

 This is exactly why I will be getting the Belkin PureAV power conditioner and filter.

 Here is a pic of the one I want:
http://catalog.belkin.com/PureAV_det...duct_Id=178914





 Here is the PureAV lineup.. they look and perform spiffy.
http://catalog.belkin.com/PureAV.pro...tion_Id=202493

 Thanks Febose, you and other reviewers have helped me push towards my own power console._

 

It would be interesting to see what's under the hood with those Belkin PureAV Conditioners.

 From a glance, and knowing their product lines, it seems that it is nothing more than a fancy version of their Isolator surge strips.

 But if it is quite heavy and there are transformers in there, then it is most definitely not just that.

 After checking out their overpriced PureAV UPS units, I am skeptical of any of their PureAV products.

 -Ed


----------



## Hiratsuka

If you want to see the insides of a PureAV, Best Buy has a display with one that has a clear acrylic case.


----------

