Powerful, affordable protection from Furman.


Written By Nikki Zanky

The power I plug my amp into is filthy. It's contaminated with noise from computers to neon lights and all of this noise ends up degrading my sound--or worse. I didn't know this until I lost an amp to a power surge. Or rather, I should say I had heard about the dangers of unfiltered power, but didn't really know the extent of it.

When I bought a new amp to replace the fried one, Musician's Friend asked if I wanted to review a Furman power conditioner because a lot of smaller gigging bands don't realize how badly they need one. I wanted to give it a go and see if it really was a must-have piece.

When I got the box from Musician's Friend, I went over all the features of the single-rackspace units--the 15-amp Furman PL-8 Series II and the PL-Plus Series II power conditioners. The front panels each have one switched outlet, a switch for the optional gooseneck lamp on the back, a master switch for all outlets, and retractable LED rack lights with a dimmer control. The PL-Plus also has a front-panel 20-segment LED bar graph meter that displays incoming voltages. The back panels each have eight outlets plus a BNC connector for a gooseneck lamp.

To the gig

When I brought the PL-Plus Series II to my next gig, my bass player was delighted to see I had a Furman power conditioner in hand. He used one with his former band and he swore some of the noise in our system at this particular club was caused by the refrigerator cycling on and off. He was convinced the Furman power conditioner would do the trick. Well, we hooked everything up and our sound was so much cleaner. The conditioned sound of our PA was a revelation--sort of like the feeling you get after cleaning the windshield. I never knew how great my amp could truly sound before. And I think he was actually right about the refrigerator.

The retractable LED lights and the optional rear-panel gooseneck lamp were a blessing in this dark club. I'm usually trying to hold a flashlight in my mouth as I set up my rack while talking to people. With the power conditioner's convenient light, I could actually see everything and talk without a flashlight-induced impediment.

I knew this bar would be the ultimate test of the power conditioner, as it was the very place that killed my last amp. I plugged the Furman into the very same evil outlet. The LED meter was really handy because I could see if the incoming voltage was in the green normal range, in the yellow moderate, or the red for extreme high or low voltages.

Ahead of the crowd

The meter was green at first but glances throughout the show proved this outlet had some seriously dangerous spikes and sags. I was glad the unit wasn't "self-sacrificing," meaning it protects your gear by sacrificing itself during a surge, but then you have to send it in for repair. My bassist said that older Furman conditioners and their current competitors' units work that way.

Thanks to the Series Multi-Stage Protection Plus (SMP+) circuit in the Series II conditioners, damaging transient voltages are safely absorbed, clamped, and dissipated. Surge after surge, the unit will keep protecting itself and your gear. Furman's over-voltage circuitry even protects your gear from damage due to accidental connection to 220V outlets by shutting off the incoming power until it is corrected. With the Furman Series II conditioners, you can just put one in your rack and count on protected clean power forever. No more worries.

Furman's LiFT (Linear Filtering Technology) is another of their unique technologies that makes the Series II conditioners superior and made our sound so clean. With linear filtering and no leakage to ground, LiFT dramatically lowers AC line noise across the entire audio bandwidth. We could literally hear the difference these technologies made.

My new best friend

I tested the industry standard PL-8 Series II power conditioner through the outlet I plug my amp into at home and it was much quieter there too. Though it lacks the voltage LEDs of the PL-Plus, the PL-8 offers all the same protection and noise filtering. I can't believe I could have gotten this noise-free sound all along if I had only shelled out the dough for a power conditioner--plus I would have actually saved money by not having to replace my amp.

The PL-8 and PL-Plus Series II removed noise I hadn't even known was there. Now that I know how great my amp sounds with clean power, I will never go back, even if power surges and spikes aren't threatening my valuable gear.

Features & Specs

  • Maintenance-free surge suppression
  • Series Multi-Stage Protection Plus (SMP+) circuit with extreme voltage shutdown
  • LiFT (Linear Filtering Technology) with zero ground contamination
  • 8 rear-panel outlets and one front-panel outlet
  • 15-amp rating
  • Retractable LED rack lights with on/off/dimmer control
  • BNC back-panel connector for gooseneck lamp with front-panel switch
  • Master switch control of rear outlets
  • Front-panel circuit breaker
  • PL-Plus II only: LED voltage meter ranging from 90-128V
  • Operating voltage: 90 to 140 VAC
  • Over-voltage shutdown: 140 VAC
  • Voltmeter accuracy (PL-Plus II only): +2 VAC, calibrated with internal trimpot adjustments
  • Spike protection modes: line to neutral, zero ground leakage
  • Spike clamping voltage: 188 VAC peak @ 3,000 amps, 133 VAC RMS (tested to UL-1449 and USA/CIDA A-1-1, 6,000 VAC @ 3,000 amps)
  • Response time: one nanosecond
  • Maximum surge current: 6,500 amps
  • Noise attenuation: 10dB @ 10kHz, 40dB @ 100kHz, 100dB @ 10MHz--linear attenuation curve from 0.05-100-ohms line impedance