Obviously this is in most senses an irrelevant point. Singing together no more requires romantic entanglements than any other job or art two people do together, and I don't usually speculate about the others. And if I really just wanted to know, somewhere on the net there's bound to be an article or six in which some reporter from Roanoke or Redmond couldn't stop themselves from asking. Maybe you already know. But I don't, yet, and in this moment of wondering I am sitting here listening to them sing.

This is what I know: Kat is from Virginia, Peter is from Alabama. They moved to LA to be musicians, independently, and eventually met each other and started playing together. Some of their demos found their way to Robbie Robertson somehow, and he signed them to DreamWorks and sent them to Mitchell Froom's house to make a record that sounds like DreamWorks could release it. They, and the record, are called eastmountainsouth. When they sing together, it sounds to me like something nature has been working towards.

Maybe there is an explanation in physics. With the right tools we could turn their voices into graphs and equations, and look for shared harmonics and resonant esophageal frequencies and synchronized microtonal pitch adjustments, and somewhere in that math we might find a way to quantify how their noise spectra overlap and interrelate. And maybe, with forever and patience, we could test every two other humans, and find that this is really the least of it. How many pairs of people on this planet have ever tried singing together this way? Too few, too few. We will never find out what most of them are capable of.

And maybe we'd find out, with enough trials, that love never enters into it. Maybe eternal lovers sound like frogs together as often as strangers and enemies sound united. Maybe singing together even requires some essential emotional division, and true lovers never sound right. Or maybe this is all subjective, and I hear something in these voices that is about my own dreams and models, not theirs.

But tonight I don't know. I can't test the theories, and I don't want to look up the facts. Tonight Belle is away, and I am here listening to Kat and Peter sing. I have never been this deeply in love, and I want the sounds of their voices to be about how well two people can be suited for each other. Love isn't inherently a performance art, and I don't know yet what Belle and I can make together. Maybe it will be art, or maybe the best of it will be private. But music is the grammar in which I instinctively cast love stories, and so in whatever forms our love actually expresses itself, some nights I will always hear it in songs.

There are many things on this album other than Kat and Peter's voices together. Some of them even matter a little. The music is, at the core, crystalline Americana of the sort that evokes the natural ringing grace common to bluegrass and Celtic. Kat plays acoustic guitar, Peter plays anything with strings or keys. Various seasonedly professional studio guests lend shimmery layers of discrete atmosphere and spiky infrastructures of mutedly crossover-hopeful rhythm. Froom makes everything bigger and more polished and more gauzily cinematic than it probably had to be, but Peter co-produced, and keeps things from soft-focusing out of legibility. The production never obscures the people. They've heard Wrecking Ball and Living With Ghosts and Shoot Out the Lights, or reconstructed them implicitly. Kat and Peter may also have a spare Welch/Rawlings bluegrass murder-song album in them, and it might be ten times better than this one, but this one still sounds grand. The lyrics are appropriately plaintive and haunting, about hardship and loss and parting, and tinged with cabin doors and mountain clearings and rivers and canoes and an unbrandished faith.

And Kat and Peter do each sing by themselves at times, but even if I put an isolated measure on repeat, it mostly doesn't register for me. Individually, they are fine and invisible. Individually I like Kat better than Sheryl Crow and Peter better than Pete Yorn, I guess, but if this record's music were the accompaniment for either one of their voices, the combination would be pleasantly competent background to me. When they sing together, everything changes. Something opaque in the universe blurs translucent, and I can make out the shifting outlines of secret truths. They sing like two hands playing one instrument, or lifting one weight, or touching in sleep. They sing like Ben and Tracey's Idlewild nursed back to health by a forest creek, or Alan and Mimi raised in a more forgiving climate, or the Thompsons if they'd never been cynics, or the Kennedys trained by Gram and Emmylou instead of Nanci Griffith. They sing like their voices found each other through their own internal chemistry. They sing like they have found, or like they are, the solution to life's hardest problem, and now all the easier ones will simply unravel. They sound to me like love feels to me.

And of course, love is easier in songs than in life. Songs are moments, and it is easier to be in love for moments than for life. I won't pretend that Belle and I know what we are best at together, yet. There are things we do together that already feel like they've always been effortless synergies, and things we do that feel brand new, and sometimes the new ones actually feel more profound. Our lives together don't end every three and a half minutes, and that's why they have potential. Kat and Peter don't have to have individual identities if they can sing together like this, and Belle and I don't have or want that luxury. Love, after all, is the easiest part of love. A door opens inside. I wake up with her, and it is already flowing through me. I wake up without her and it is still already flowing. I know things I can't possibly defend. Those are the easy parts, at least for me. The hard parts are all the constraints that songs can simply ignore. We don't have patrons or producers, and we don't always get to rehearse first. We want to combine our two lives and get three, not one. Contemplating lifelong promises can be terrifying, because anything you promise to do forever implies that there might be something you're giving up on. But lives are finite, you're never going to do everything, and I believe we can do greater things together than apart, and greater versions of the same things. Maybe they won't be songs, but then maybe I already know how perfect songs would sound.

Haley Bonar's ...The Size of Planets is more or less an opposite treatment of the same fundamental aesthetic underlying eastmountainsouth. Where Kat and Peter had southern summers and Robbie Robertson and Mitchell Froom and DreamWorks, though, Haley had South Dakota winters and Low and Chairkickers' Union. Her songs are as guarded as eastmountainsouth's are expansive. Many of them are just Haley and a guitar or piano, only sparingly augmented by drums or cello or slide guitar, recorded with careful unobtrusiveness at Sacred Heart in Duluth by Eric Swanson. Most of them are about pain, many involve drinking. In a nature/nurture debate, I might argue that ...The Size of Planets and Living With Ghosts and Sarah Harmer's You Were Here and Kathleen Edwards' Failer are all manifestations of the same basic impulses, filtered through different trusts and different cities. Haley was only twenty when she made this, and I think Low found her because she sounds like this, not vice versa, but Alan and Mimi have a daughter, and it's easy for me to imagine this album as a result of growing up in their house.

And if all labels were created equal, ...The Size of Planets and Failer would now be set on similar courses. Haley and Kathleen are prodigies of a type, older-sounding than their age, their characters worn by similar forces. Haley's "Save a Horse, Ride a Cowboy" could be an oblique sequel to Paula Cole's "Where Have All the Cowboys Gone?", turning inward and wondering why anybody would want those stereotypes. "Am I Allowed" is Patty Griffin-esque in both intensity and text, a bleak small-town lament that could easily have played over David Gordon Green's All the Right Girls. The clipped "Drinking Again", lurching on unsteady drums, is acoustic-blues worthy of Chris Whitley. "Car Wreck" is a stunning interior monologue from a drunk car accident that might as well be a suicide. "I sang about the things I love", she remembers, only the way she says the word "love" it could as easily be "like" or "lack". "Bless This Mess" is becalmed and howled, like a return to Patty's "Poor Man's House". "Sun Don't Shine" sounds like a piano exercise for the hopeless. "Out of the Lake" simmers with the swallowed menace of The Sweet Hereafter. "Billy" shivers and feints towards catharsis, but subsides and bleeds into the fragile, pleading "Go Away Angels".

And Haley doesn't usually bother to harmonize with herself, but she makes an exception for "Razor That Wins". And maybe she has learned harmony from Mimi and Alan, too, because her version of it makes two of her sound as lonely as Kat and Peter sound entranced. It's a suicide song, too, I guess, but she sings it like it's the pain from pushing toxins out through your skin, and in this context the auto-harmony is a defense and an escape. "It's the love that remains / On the hems of your clothes / And the marks on your skin", she sighs, and maybe it's his suicide, after all, and his memory that haunts her. "Little Bird on My Shoulder" doesn't bother dispelling the mood, riding the low hush through a song that would be poised and open if it weren't so close to disappearing entirely. Pensive electric piano and distantly booming drums pace the bleary "The Water", like an "American Pie" for anyone who thought the occasion deserved a funeral march. "Laughter can't fill the silence", she claims, but since when is that the criteria for anything? "My ship is sinking, but that's okay, I've always liked the water." This is too dreary to take seriously, and between my laughter and her resignation, we fill the silence pretty easily. "Lullaby" dies away into it, and it still doesn't feel very empty to me.