Furman Sound PL-PLUS II User Manual

I N T R O D U C T I O N

Thank you for purchasing a Furman Series II 

Power Conditioner, and congratulations on 

your choice. 

 The Series II power conditioners 

feature Furman’s revolutionary  Series Multi-

Stage Protection Plus (SMP+) circuit, as well 

as our exclusive Linear Filtering Technology 

(LiFT).  Together, these technologies comprise 

what is, without question, the world’s most 
advanced and comprehensive transient 

voltage surge suppressor / conditioner.  

SMP+  (Series Multi-Stage Protection 

Plus)

Furman’s SMP+ surge suppression virtually 

eliminates service calls.  Traditional surge 
suppression circuits “sacrifice” themselves 
when exposed to multiple transient voltage 
spikes, requiring the dismantling of your 
system, and repair of your surge suppressor.  
Not so with SMP+.  With Furman’s SMP+, 
damaging transient voltages are safely 
absorbed, clamped, and dissipated.   

Unique to Furman’s SMP+ is its unparalleled 

clamping voltage.  While other designs offer 
clamping voltages that are well above 330 Vpk, 
Furman’s SMP+ clamps at 188 Vpk, (133 VAC 
RMS) even when tested with multiple 6000 Vpk 

- 3000 amp surges!  This unprecedented level 

of protection is only available with Furman’s 

SMP+ technology.  Additionally, Furman’s 

trusted over-voltage circuitry protects against 
all too frequent accidental connections to 208 
or 240 VAC, by shutting off the incoming power 
until the over voltage condition is corrected.
[For E versions: Furman’s SMP+ clamps at 376 

LiFT (Linear Filtering Technology)

Unfortunately, traditional AC filter - conditioners 

have been designed for unrealistic laboratory 
conditions.  Prior technologies, whether 
multiple pole filter or conventional series 
mode, could actually harm audio and video 
performance more than they help, due to the 
resonant peaking of their antiquated, non-linear 
designs.  Under certain conditions, these 
designs can actually add more than 10 dB of 
noise to the incoming AC line!  Worse still, lost 
digital data, the need to re-boot digital pre-sets, 
or destroyed digital converters are frequently 
caused by excessive voltage spikes and AC 
noise contaminating the equipment ground.  
Furman’s SMP with LiFT takes another 
approach, ensuring optimal performance 
through linear filtering and no leakage to 
ground.

S A F E T Y   I N F O R M AT I O N

To obtain best results from your Furman Series 

II Power Conditioner, please read this manual 

carefully before using.

2