Hip-hop nerds know him best from his origins in Ohio's MegaHertz crew or his boom-bap slaps with MC Blueprint as Soul Position. Sample junkies have been following him since his 2002 solo debut, Deadringer (Def Jux). His aural reach expanded when he began singing himself (Since Last We Spoke) and relying less on found vinyl and tinkering more with synths and drums (The Colossus). And your mom has heard his work on the opening theme to TV's Mad Men and commercials for BlackBerry and Radio Shack. Now 35-year-old Ramble John Krohn, better known as rjd2 (all lowercase, his publicist specifies), has produced an entire album for a singer and fellow Philadelphian you ought to know. Under the moniker Icebird, rj and Aaron Livingston (a Black Lily alum who has worked with the Roots) unleash The Abandoned Lullaby, a stirring and swerving soul-jazz-rock-psych album that showcases the range of both its lead vocalist and its veteran producer. We caught up with the instrumental half of the new duo as he drove around in a van.

To which album of your past catalogue could you compare the new Icebird project?
A Soul Position record is more analogous to a record like this than one of my solo records because it is really a group effort. Aaron wrote all of the lyrics and all of the vocal melodies. In addition to that, he played drums on one of the tunes and he played guitar on some of the record. It was very much a collaborative effort.

Did you create in the same space or did you create beats and send them to him to write to?
The latter. Like a Soul Position record, I would write instrumentals and send them to him, and he would write the lyrics to them and demo up the vocals.

How much coaching did you do in terms of how he sang or his subject matter?
Kind of in an editing role. I would offer insight. It wasn't like I had final say; I would offer input, and my opinions would be considered. Little things like, "Maybe we can tweak this a bit" or "We can add a counter melody in here." In any creative process, you throw ideas out, and you find middle ground. And through that process you find out what's important to you and what's important to the other person.

So did you write instrumentals specifically for Aaron, or do you just create music and figure out afterwards which beats would best suit a singer, or an MC, or stand alone as an instrumental?
I was just shooting something for exciting and interesting. The training wheels come off in a scenario like this. If I was working on a rap record, I'd probably try to make sure everything was in four-four. There's so much more variety and different ways to take the music on a record like this. Take "Gun for Hire": There's no way in a million, bazillion years I could sell a rapper on doing a tune like that. There'd be a one percent chance.

How has your relationship with hip-hop changed over the years?
That's a tough question to answer. It's a hard thing to put into words, frankly. One aspect of that question is that I gave a shit about arguing about rap. If you were to go back ten years, you could bait me into an argument about rappers or rap music or hip-hop. That was a possibility. Up until 2005, 2006, maybe 2007. But at some point in time… there is no way to bait me into an argument about hip-hop. And there's a 40 percent chance that I will light myself on fire and run free from the scenario. [Hip-hop] is going to do what it's going to do, and I'm just a bystander. Ten years, five years ago I felt I was part of the conversation.

How much of your time is spent listening to rap these days?
When I feel like it. When there's good rap records out, then I'll listen to it a lot. But when there's not good rap records out, I don't listen to it a lot.

What are the chances of another Soul Position record?
Gosh, I hope. I've been pushing on that, trying to make that happen. Been doing what I can to make it happen, but you know…

What did you think of Blueprint's new solo record?
I liked it. I thought it was really good. I'm happy to see him step out and experiment. Step outside of the box of rapping over underground rap beats.

When and why did you move to Philadelphia?
[I moved in] 2002. Coming of age in Columbus, it became claustrophobic. It got to the point where I was like, I wanna get outta here. I had been going to New York a lot for work, for music stuff, and I thought the East coast would be easier on me. I liked the idea of being more anonymous. Because Columbus is so small, if you so much as drop a seven-inch, people start to know who you are. When I started out with my click, the Megahertz guys, we were the only guys who were really doing any East coast hip-hop in Columbus, Ohio, at the time. At the time, my first experience with people recognizing you and talking to you on the street ― it was weird. It was a culture shock.

So do you get recognized walking down the street in Philly?
It does [happen]. Now that I'm acclimated to it, it's not a problem. But at the time, it was a symptom of what Columbus, Ohio is like and partially a symptom of where I was at in my career.

How did you meet Aaron? You guys first worked together on your Colossus record.
I stalked him, pretty much. That song he sang, "Guns Are Dawn," on the Roots' Tipping Point album, I always loved that record. A mutual friend of ours gave me this CD of his group, the Mean, and I dug up his number, called him up and said, "We should record some music." And that was that.

What's the significance of the Icebird name?
It was one of those things that was knocking around. I had a long list of names in the running for the group, and I've always been obsessed with all things ice or frozen. Maybe it goes back to a Metallica song, "Trapped Under Ice," or maybe not. The name "Iceberg" came up ― the thing that sunk the Titanic. But that seemed kinda pedestrian, and I think there was a '70s prog band called Iceberg. So I tweaked it to Icebird, and it sounded cool.

And you're pretty much recording exclusively out of your home studio now.
It's not that I'm opposed to going into a real studio, but out of necessity, yes. Basically everything I've put out has been written, produced and recorded in my own studio ― all my records were. A studio is always a work in progress; it never stops. It's like working on a song: you can work on it forever. If you have a laptop and a microphone, you have a studio. If you have an MPC, you have a studio. The threshold of what qualifies as a studio is pretty low, as far as I'm concerned. The critical part is buying all the gear, and that started in 2003. From 2004 to 2006, I hit it pretty hard. I got completely obsessed with engineering and I spent long, long nights and days setting up mics, trying to get drum sounds, buying synthesizers and restoring them, on and on and on. I still do that.

Where does that interest in the technical side originate?
It was really born out of necessity. I had an epiphany right after Deadringer, my first record, came out. And that epiphany was, I'm not going to sustain a career just buying records and being sampler guy. When you do that, your ability to be creative is 100 percent tied into what samples you can find.

How did landing the Mad Men theme affect your life?
Gosh, I think it was more of a visibility thing. It wasn't a huge windfall, to be honest with you. Not in the least. It was one of the lesser financially profitable things that I've done.

But it opened up doors.
More people are aware of what I'm doing in that world. All these things contribute to me staying in people's minds as far as being someone who's active. In that world, you have to constantly remind people that you're still alive.

Is that something that bothers you? You've had such a long run and been able to try so many different sounds. Do you ever wonder, "What if they stop buying or stop listening?"
To be honest with you, yeah. It's not like I freak out and panic. My number one hope is to be able to continue to do music that I'm happy with. I want to do different styles of music, continue to be active and do music I'm happy with.

So what's next?
I haven't thought that far ahead. I don't know yet.