So what about the newest incarnation of the Punch EQ? Well, I have to admit, and am a little surprised to say, it wasn't bad! I was expecting the top end (the treble boost occurs around 12kHz) to be brittle and hard, and if I really cranked the EQ into it I could get it that way, but overall, with a bit of restraint on the adjustment knob it did a great job of bringing the music to life. In a vehicle, especially one with less than optimum tweeter placement, this redone version of the old Punch EQ circuit of the '80s could be really useful. I have to admit I didn't really care to listen to it much in my lab, but in a vehicle, I can definitely see a benefit to providing a little help to both ends of the spectrum.
Performance
After spending the better part of an entire day listening to the T600-2, I was eager to get some numbers out of it. So, I hooked it up on the deadly accurate Cogent bench and fired up my Audio Precision.
Any concerns I'd had about reduced power went out the window with the first couple of power measurements. Making over 380 watts per channel into 2 ohms, and over 780 watts bridged into 4 ohms, compared to the amp it replaces, this new Power-series amp makes the same power in a much smaller package and for even a little less money than last year's version. Distortion at rated power was below the published specification, and when pushed, the amp clipped cleanly and evenly, with no asymmetrical waveforms developing.
Reassured that it still had all the power you'd expect from the premium Rockford Fosgate series, I went on and measured the more intimate details and nuances. As soon as I started the frequency response sweeps, I saw that my hypothesis was correct, this amp is in fact intentionally designed not to have a flat response. With boost evident from 20Hz to 200Hz, it's no surprise the amp had a warm, rich tone to it. And on the top end, I found boosted highs from about 2kHz to 15kHz, which might have had something to do with the detail and presence I noticed earlier. The inter-channel gain difference was limited to about 0.2dB, which is good for a single-ganged pot.
Signal to noise measured very good, at better than -87dBa reference to 1 watt of output. Evidently, that EMI Shield installed between the power supply and the input circuitry was doing its job.
Efficiency at full power was about average, at 65 percent, and the amp had an input voltage adjustment range of 200mV to 8.0 volts. The crossovers measured as advertised, with true -24dB slopes, and the selected frequencies silk screened on the panel were reasonably accurate. There's about +4dB of unadvertised boost when you engage the lowpass crossover, so be sure to set your gains with the crossover selected as you intend to use it. I didn't care for the tiny adjustment pots that required a small 2.5mm screwdriver tip, but I'm old and my eyes aren't what they used to be. Still, in a dark trunk or under a car seat, these tiny fully recessed pots are going to be a pain.
The amp protected instantly when I dead shorted it and recovered automatically when the short was removed.
One of the reasons the Cogent bench is seldom empty, is that I regularly measure and develop special tests for weird things that no one really cares about until they have a problem. In the case of the T600-2, I didn't find a problem, but I did notice that while it does turn on and off dead quiet without so much as a tick, the amp turns on a lot faster than I'm used to for a Rockford Fosgate (in less than 1.6 seconds, to be exact). I tend to prefer amps with a slower turn-on time, say somewhere around three to four seconds. Why does it matter? Well, sometimes if you have a signal processor, EQ, or preamp upstream of the amp, it can take a couple of seconds for it to "settle" when first turned on. If the amp is already on, any "junk" that finds its way out of a device upstream will be amplified, and cause a turn-on tick, pop, thump, etc. Not a critical deal, but something to be aware of if you ever have a turn-on noise issue with one of the amps.