Peachtree Audio‘s frontman Jonathan Derda is a terrifying man. I mean, sure, he’s all spit-and-polish in the room, all professional with his smooth baritone presentation and casual dress. But beneath those dark, wavy curls lies a mind actively plotting world domination. Pinky, meet The Brain. Cower, mortal. Tonight, we’re taking over.
I’m only partially kidding. It takes a special kind of person to bring a pair of Martin Logan hybrid ESL loudspeakers to use in a demo. Someone sporting big, brassy, clanky ones. I mean, have you seen the measurements on this speaker? Fronting these speakers should be a placard shouting “Do Not Try This At Home”.
Fine, no, there’s not going to be fireworks (well, probably not), but precision? Detail? Air? Hah. Good freaking luck. Which is why Jon’s low, slow chuckle was more than a bit unnerving.
Like any talented magician, Jon had a couple of tricks up his sleeve. First up was his new integrated. The $1,999 nova220SE is Class D amp with the signature Peachtree tube stage, and sports an ESS Sabre DAC chip, with up to 192kHz sampling. This amp is rated to 220wpc into 8Ω and good for 350 into 4Ω, but the minimum suggested impedance of a loudspeaker was 3Ω. The Montis, nominally a 4Ω speaker, do that lovely Martin-Logan drop to .7Ω (or lower, check the measurements). You’d be forgiven for wanting a bucket of popcorn whenever the crescendo hits, because surely, “bad things would happen”.
Except they didn’t. There was quite a lot of head-scratching on that one. Well, there was me, scratching my head …. Whatever. Instead, the the sound here was brilliant. The Montis were controlled and I heard everything that an ESL would bring to a party. In fact, it actually made me like a Martin-Logan and that’s saying something.
After the demo, John launched into his spiel again, this time extolling the virtues of the new Amarra 3.0 IRC software. With this room-correction package, John was able to nail down a very linear response curve, and then tuned it to his particular taste. I’ll let Jon explain what we’re looking at.
Attached is a pic of the frequency response as measured in the room by Amarra’s IRC (DIRAC) feature of our system. Measurements like this really lay a system bare. The blue lines are the frequency response before correction. Can you say room modes? This was after spending half the day positioning the speakers by ear.
The orange line is the target curve. IRC sets this for you but you can tweak it manually if you want some mid-bass hump. (I just wanted to use the word ‘hump’.) The green line is what you get after correction is applied. You can see even without IRC everything from 400Hz on up is very linear. We applied IRC just in the 24Hz-400Hz region to remove the room’s sound. IRC resulted in improvements in reproduction of the fundamental notes and clearer harmonic detail without changing the personality of the speakers/amp/DAC combo. It simply took the room out of the equation. That this level of subjective and measurable improvement can be had for just a few hundred bucks as part of Amarra 3.0 w/ IRC(b) blows my mind.
And that is how wizards work.
Also in the room was a new prototype DAC from Peachtree that Jon called sonaDAC. Cost should be less than $2k when it’s launched, but will be fully-balanced, all discrete Class-A, will support DSD and PCM up to 384kHz, has a built-in headphone amp, and yes, that is a
big knob volume control. ETA is “later this year”.
Signal cables, power cables and power distribution for the demo came from Shunyata. Audioquest’s Coffee USB cable ($349) made the connection to the computer. The rack was an S3 from Solid Steel ($599). Total system price was just under $19k — you just ned to add your own iPad and Mac.