In case you think I was a little too harsh on Astell & Kern’s AK380, and maybe induced high IMD/THD because of overdriving the Earsonics SM2, at the exact same volume, Maestro keeps distortion levels to about 5% of a similarly loaded AK380. At max.
Let’s praise Maestro’s versatility.
It runs excellent signal to a super-duper wide variety of headphones, where apart from stereo crosstalk, signal quality decays by less than 5% in contrast-based metrics. And that whilst running the Ultrasone IQ, Earsonics SM2, Beyerdynamic DT880, and Audio Technica ES7.
Maestro’s masterful grip, channel balance, and blessedly low noise signature are boons to earphone users. Yes, earphone users. Despite Maestro kicking out desktop speaker-level volume levels like it was digital. Balance is perfect from the lowest volume settings, even through sensitive levels through headphones such as the 600Ω DT880, it tracks perfectly from its base volume through sensitive earphones such as the Ultrasone IQ. This is pretty-much unheard of in a desktop amp. BTW, when I say base volume level, I mean the lowest setting out of which volume spews from the likes of the IQ. Naturally, iTunes or Audirvana is set to maximum. So is the Vivace. Left/right channels track perfect enough for the insanely sensitive Shure SE846.
That said, through sensitive earphones, you will notice Maestro’s base volume suddenly jump from nothing to about 50dB. Quickly from there it hits 80dB, so while track balance is impeccable, there’s not a lot of headroom for quiet listening or the deadly combination of sensitive earphones and ears.
This leads me to Maestro’s singular no-no. Its volume jumps too quickly from low to high volumes, and because the pot is so damn slim, it’s hard to fine tune. If you’re a camera dude or dudet, read it like this: Maestro’s rangefinder baseline is like 28mm rather than 58. Sure, you can nail a desired volume level (focus plane), but it takes a lot of fiddling. Still, Maestro spits a comfortable signal to FitEar’s MH335DW from 8 o’clock till about 9:30 on the pot, which is a rotational travel of about 20 degrees. For an amp as powerful as Maestro is, that is good.
The background noise it foists on sensitive earphones is about even with an original AK100. If you really don’t like hiss, and you’re primarily an earphone user, Maestro may spit too much noise for you. But if you primarily are an earphone user, you’re probably not interested in Maestro in the first place.
Fed from Vivace’s XLR fixed (max volume), Maestro supplies the ample current to the 600Ω DT880 to keep all but THD to a minimum- and that while shirking enough IMD sizzle that the DT880 is cleanly doing a desktop speaker thing. Even at that insane volume, Maestro kicks out over 114dB of dynamic range and keeps IMD below 0,005%. Insane, right?
Naturally, I won’t listen to it at that volume. And neither should you. Whilst enjoying Alpha Dog, or ZMF headphones, I keep the single-ended volume set to about 12 o’clock. Balanced, I keep it to about 10:45.
Maestro and Vivace are a great match. In fact, it’s great to have reviewed the AK380 this week as it is an audio contemporary to Vivace. Vivace doesn’t supply quite as good stereo crosstalk performance, nor as good detail along its sound stage. It is slightly too contrasty for that. But both interpret music through a similar semi-liquid, warmish signature.
Maestro is more is neutrally voiced than Vivace, and it scales well with good sources. While both have perfectly flat signals from top to bottom, Vivace is a bit warmer. Maestro’s bass is super grippy, but it spits even definition in each frequency band across the entire stereo spectrum. No mids here, bass there, highs over there. Yep, it’s got that wall-of-sound thing going on that is delightfully big-sounding trance, EMD, live rock, classical, and more. But it doesn’t give up high-frequency stereo detail to mids or lows. Its sound stage is wide, totally flat out and up, and drilled through by evenly weighted lows, mids, and highs.
Its single-ended output is, with the exception of a merely good stereo crosstalk performance, nearly flawless. Its balanced outputs quite a bit more power, perhaps to the tune of 8-10 dB through most HiFi headphones, and a bit more through the DT880/600. Through it crosstalk and stereo detail improve, albeit in toddler steps.
It is my personal l opinion that both warm and cool-sounding headphones fit Maestro to a T. Well, its wall-of-sound soundstage is perhaps too much of a good thing when paired with a 700-series AKG. Even the DT990 may be a bit too punchy for it.
Conversely, the Maestro/Alpha Dog combo took me a while to get used to. At first I thought it a bit too warm, preferring ZMF’s brightest Vibros to it. But, because Maestro is absolutely neutral in stereo detail, mids don’t jump out at you, no matter the headphone; and for that reason, Alpha Dog’s sometimes heavy-handed mids-bass thickness doesn’t get too damp, but sparklier, more open high-frequency stereo detail would wake that headphone up.
Maestro works wonders with the DT880/600.
As to earphones, I find the Ultrasone IQ-Maestro combination bitier than the FitEar MH335DW-Maestro, and therefore, more to my liking. Your mileage will vary.
Maestro is ready for prime-time. It is extremely powerful. Ugly as it is, its wall-wart shirks ground hum and most other noise. Its hiss signature is stable, and very low in volume. While its RCA input doesn’t excite, its XLR inputs are incredible. Come to think of it, Maestro’s RCAs: in our out, sound or feel, stink of an afterthought.
Its volume pot is Lovecraftian. But it is tied to a brilliant tracking attenuator that nails L/R channel balance from the SE846 on up. Insane.
Part of me wishes that Linnenberg had a harsh editor behind him, to clean up his few mistakes. (I could do with one, too.) Because, that pot bigger, and in a better place, and those RCA jacks sturdier, and maybe with a better website behind it, Maestro would be the Jack of all trades headphone amp. It is a brilliant amp that performs great. I only wish its knob was easier to twist.