With responsible power comes great reliability
By Darius Van Rheuhl
Musician’s Friend Staff Writer
I’ve made the point before that like the rest of my fellow audioholics, I’m attracted to shiny objects. But I have learned the very hard way that with audio equipment, you need proper power conditioning to keep everything shiny. I know you really want that Chandler Germanium, or A Designs Audio Pacifica, but before you subject any gear, new, old, and especially your prized stuff, to untreated AC, you need to have a quality power conditioner in place—and I have just the one for you: the Furman PL-PLUS DMC. It’s affordable; it’s advanced; and it will let you get the most out of your equipment, not only in terms of longevity but sound quality as well.
You need an outlet
The PL-Plus DMC is equipped with eight rear-panel outlets in two isolated banks and a front-panel convenience outlet. To deal with the whole wall wart thing, where one line-lump or two can suck up half your power strip, the DMC has three outlets spaced wide so you can have access to all the outlets you paid for. The PL-Plus DMC also features LED rack-lights, which produce virtually no heat and provide an extremely long lifespan. There’s also a rear-mounted BNC jack that accepts any standard (12VAC 0.5 amp) gooseneck lamp for rear rack illumination.
Power to the PL
The PL-Plus DMC’s 15-amp, 1,800W capacity is supplied by a very substantial 14 AWG, 10' AC cord, which is indicative of the DMC’s overall build quality, and a nice touch if you forget to carry an extension cord. To give you an accurate reading of what’s really coming out of the wall, there’s a switchable digital precision meter with an accuracy of ±1.5 volts. The meter has a tri-color readout that’s set up like a traffic stop light: Green means everything is go; red means incoming voltage is potentially damaging; and amber, which does not mean play as fast as you can to get through the set; it means caution, voltage is not optimal. I found this to be a rather handy option. If you’re too far away from the meter to read the numbers, the color lets you know if voltage coming into the unit is within the safety margin or not.
Looks like you could use a LIFT
There are certain products, or should I say, the hyping of certain products, that tend to sound like snake oil (whoever thought of snake oil; as if they weren’t slippery enough?), but in reality, unfiltered power does have a noticeable effect on sound quality and increases wear and tear on components. AC power by its very nature makes noise. In fact, just proximity to the magnetic fields generated by an AC power supply can radiate noise into your audio path. That’s why manufacturers of high-end, audiophile recording gear, such as GML, build external filtered power supplies for their gear.
Unfortunately, traditional AC power conditioners have been designed for laboratory conditions, but our gear has to live in the real world. In fact, the older nonlinear designs can actually hurt audio performance by adding noise at various frequencies (resonant peaking). Under certain conditions they can add more than 10dB of noise to incoming AC. The result can be anything from lost digital data to the destruction of digital converters, which is frequently caused by excessive voltage spikes and AC noise contaminating the ground of your equipment. Furman’s LiFT (Linear Filtering) takes a new approach to this dilemma by reducing noise to extremely low levels in a linear fashion, and with no ground contamination.
Paying for protection
Besides the shortened life span of your gear due to unfiltered AC, there’s another gang of nasties that pose a more immediate threat. We’re talking surge and spike protection. Relax, no payments need be made to the Russian mafia and their pit bull—just a small one-time payment to Furman, does the trick.
Surge and spike, on the other hand, will mess you up. When exposed to multiple voltage spikes, traditional surge suppression circuits will "throw themselves on the hand grenade" to protect your gear. Noble, yes, but the bad is that your power conditioner and gear may become collateral damage (in both the life-threatening and financial sense of the word) since these circuits will still allow damaging spikes through to your gear. So, in order to avoid reconstructive surgery and long terms of convalescence in the ICU (Intensive Circuit Upgrade), you’re going to need Furman’s unique SMP (Series Multi-Stage Protection) surge suppression. What makes SMP unique is its exceptional clamping voltage rating. Clamping voltage is the amount of voltage allowed to pass through to your equipment when the protection device is subjected to a transient surge or spike. While other designs offer clamping voltages that are well above 330V peak, SMP clamps at 188V peak (in this case the lower the better). You won’t find this level of protection anywhere else. With SMP, your equipment is protected while your Furman protects itself. In fact, ever since Furman started offering its SMP protection, they’ve shipped over 250,000 circuits with not one failure due to surge (looks like surge may be out of a job).
Another protective device from Furman is EVS (Extreme Voltage Shutdown). EVS protects against prolonged overvoltage conditions, such as accidental connections to 240V AC or an intermittent neutral. If the unit detects a dangerous condition, a relay shuts off incoming power until the overvoltage condition is corrected.
DMC in the house
I used to record a live comedy show in a club where neon lamps buzzed through your amp, and the air conditioner, smoke eaters, and refrigerator were all on the same circuit as the sound system. Those high current-draw units wreak havoc on AC when they flip on and off. Go ahead, plug your stuff into that unprotected and see what happens.
It’s funny; we never seem to make the connection (no pun intended) that plugging into a wall socket is like playing RMS roulette. Your equipment was designed to operate optimally at 120 volts, and 120 volts is what we think is coming out of the wall. In reality, it can be anywhere from 110 to 126 on a household circuit, and I’ve seen worse.
If you have computers or recording gear at home, I would recommend—to the point of insisting—that you get a line regulator such as the Furman 1215 or AR 20 II; that is, if you want to continue using your computers and recording gear for a long time to come.
Run DMC, run
Obviously, having nine outlets at the top of your rack makes connecting gear easy; but why spend the bucks when a cheap power strip can do that? Here’s why: A power strip won’t protect your equipment from spikes, warn you when AC voltage drops too low, or prevent noise from doing digital damage. And if those gray powder burns appear on it during your show, you’ll experience that entire-life-flashing-before-your-eyes thing followed by a moment of solemn prayer (oh God, please work . . . oh please work . . .) as you plug in your amp elsewhere and wait to see if it turns on.
There’s a reason why Furman sits at the top of more professional racks than any other power supply; they’re bulletproof and incorporate the highest levels of AC protection technology. Speaking as an electroniholic who understands the overwhelming urge to buy amps, preamps, compressors, and processors of all kinds, the first step towards living successfully with your addiction is to clean up your AC(t) and get a Furman PL-Plus DMC.
Features & Specs
- SMP technology provides highest level of surge and spike protection available
- LiFT technology with zero ground contamination ensures clean AC
- EVS overvoltage detection circuitry safely powers equipment down
- Dual Smooth Track retractable LED lights
- LED status indicators
- Large digital voltmeter/ammeter with discrete dimmer button
- Isolated outlet banks
- 3 widely spaced outlets
- 15-amp capacity (1,800W) with 15A circuit breaker for added protection
- 9 total outlets (8 rear-panel and one front-panel convenience outlet)
- Rear-panel BNC connector
- Five-year limited warranty
- Current rating: 15 amps
- Operating voltage: 90 to 139 VAC
- Over voltage shutdown: 140 VAC typically
- Spike protection modes: Line to neutral, zero ground leakage
- Spike clamping voltage: 188 VAC peak @ 3,000 amps, 133 VAC RMS
- Response time: 1 nanosecond
- Maximum surge current: 6,500 amps
- Noise attenuation: 10dB @ 10kHz, 40dB @ 100kHz, 50dB @ 500 kHz, linear attenuation curve from 0.05-100 ohms line impedance
- Construction: Steel chassis, .120" brushed and black anodized aluminum front panel; glass epoxy printed circuit boards
- Power consumption: 15 VA
- Safety agency listing: TUV
- Dimensions: 19"W x 1-3/4"H x 10-1/2"D
- Weight: 12 lb. (5.5kg)