After unpacking the system and installing it in my listening room, I let it play at low volumes for a couple of days to break everything in before I began my listening. I use this step only for critical evaluations of brand new speakers, since break-in isn’t required under normal circumstances. The speakers will quickly normalize just from playing your system. Beginning with a few of my favorite vocal performances from Jennifer Warnes, Marc Cohn, The Manhattan Transfer, Natalie Cole and Thursday Diva, I was basically astounded by the sonics of this relatively modestly priced system. Female vocals came through with wonderful accuracy of pitch and timbre, and the system exhibited a very lifelike openness. Background detail was never overcome by the primary sounds, and the deep and strong bottom end was quite surprising. Several times I found myself re-playing tracks with good bass guitar and drum work, just to hear how well this pair of components handled the bottom end. Make no mistake, you’ll still need a good subwoofer, but the amount and quality of the mid-bass is uncommonly good. Switching to some big band and jazz, I found the H600s to be very impressive when it came to reproducing horns and acoustic piano. The tonality was very rich and natural sounding, with a warmth and sense of space that isn’t usually available anywhere near this price range.
I listened to the system with both the silk and the aluminum dome tweeters, and it quickly became evident why Diamond offers both types. I also found that I could alter the sound of the system quite significantly by inverting the polarity of the tweeter, and I’d suggest experimenting with this once the system is installed. The sound from the silk tweeter system is very smooth and polite, and for my tastes it’s best when you are listening on-axis. The aluminum tweeters have decidedly more output in the extreme upper register, and have a bit more “sparkle” than the silk versions. Neither was spitty or sibilant and although I’m not generally an aluminum tweeter fan, I found I could listen to these for long periods with no problem at all. The H600 system is very decidedly aimed at the sound quality listener, but is still quite capable of playing at higher volume levels, but it’s probably not the best choice if you prefer concert-type SPL to sound quality.
On the Bench
After the listening was over, I moved the system to the lab for some measurements. Here I checked the impedance, frequency response, distortion, and sensitivity. All of the parameters were well within the published specs, and the graphs of those measurements are below.
Recommended Power: 85/170 Watts
Sensitivity (2V/1M): 85dB SPL
Frequency Response: 60Hz -30kHz (-3dB)
Mounting Depth: 2.4” (61mm)
Mounting Diameter: 5.4” (137mm)
Midrange Resonance: 48Hz