The Federal AM-864/U was made for the US Army in the '40s and '50s for use in AM radio broadcasting. Like most obscure, vibey pieces of vintage gear, these have recently become prohibitively expensive, and replacement parts are scarce. Moreover, it's nearly impossible to tell which version you're buying without looking inside; some are full bandwidth and others are broadcast models which have fairly narrow bandwidth. Enter TJ Schmidlin, tube-circuit wizard from southern Ohio. A few years back, he decided to circumvent these issues by recreating - and improving - the charming single-knob compressor he was so fond of.

The Schmidlin Fed+ sports a number of solid upgrades while not altering the integrity of the original design. Inside are British and US transformers (nickel input and steel output) that contribute to a very balanced, transparent sound. The signal capacitors are glass-sealed, paper-in-oil types. This is important. Paper-in-oil caps are expensive because they are considered to be the most transparent, bar none. They are actually hard to find in any new equipment. Glass-sealed means they will never dry out. Proper signal transformers make the unit full bandwidth (20 Hz-20 kHz). Unlike the original, the Fed+ has controls for threshold, ratio, attack, and release, making it much more versatile. With all of these additional knobs set at zero, this unit operates just as the original. Aesthetically, it's handsome and simple; easy-to- read white lettering on a black faceplate, with super precise markings, allows for easy recall. The impressive 3.5'' attenuation meter is front and center.

My unit showed up packed securely and was ready to track in 5 minutes. Its first duty was on a ribbon mic in the room, tracking drums for the Old Gods record last September. Old Gods are a blazing and tough-sounding metal band from Detroit. Drummer Tony Wolski plays with precision, speed, and power; and the Fed+ really focused the room sound without changing its character. The cymbals were smoothed out without any blurriness, and the Fed+ emphasized the low- mids in a pleasing manner, adding warmth and heft while not muddying the signal in the slightest. Awesome!

Next up was a week-long tracking session with K-Holes from Brooklyn. They make super exciting and crazy yet dark-as- night rock music - like The Scientists on Adderall armed with Z.Vex pedals. The Fed+'s task on this session was the buzz-saw bass playing of Julie Hines. Her tone ranges from clean and midrangey to a total blown-out onslaught, oftentimes in the course of seconds. The Fed+ handled this and did something I have heard few compressors do; it seemed to pull the notes out while taming the attack. Again, the low-mid thing was both palpable and totally killing. Okay - I'm liking this thing a lot.

Vocals are what separate the wheat from the chaff for me. I'll use any compressor or preamp depending on mood or circumstance for most things. Tracking vocals is where I seem to notice things I may not otherwise during the course of normal rock record-making. Soft Location were in for a weekend to track a full-length. Kathy Leisen's voice is at once disarming and engaging, new and familiar. She is one of those singers that is plain easy to record. We used a Korby KAT251 mic (Tape Op #38), a Calrec 1161 preamp (no EQ), an Empirical Labs Distressor (#32), and the Fed+. The Distressor set at 6:1 handled the fast stuff, and the Fed+ the slow overall stuff. This is usually where I use an LA-2A or similar. Things were moving fast this day, and while checking options, to my amazement I realized I had the Distressor bypassed and was slamming the Fed+ harder than I would normally. The reason I was surprised speaks volumes. You really can't hear this thing - even when you abuse it - and this was the first time in a few years that I decided to stray from this basic two-compressor setup. Fighting my desire to make the Fed+'s meter stop dancing so violently, this was the vocal sound for the record! The vocal was super upfront and intimate. The low mids needed tailoring here and there, but it took very little EQ to do this. The top end was beyond silky or airy; it was just right. This is why real top-shelf gear is so gratifying; even when you make what's technically a mistake, you discover something awesome - like the first guy to push in all of the buttons on an 1176, except in this case, the result was more widely useable in a musical way.

I've covered some of my day-to-day uses for the Fed+, but I am by no means at the end of my list. The Fed+ gets used on drums often. Total Fleetwood Mac snare thickener - and mono overheads are almost 3D. I was totally able to get a killer sound on the kit with an AEA R84 ribbon mic (Tape Op #38) as an overhead through the Fed+ using only an AKG D 12 on the kick to supplement. On acoustic guitar with a Michael Joly-modded Oktava MK-012 condenser mic (#25), it was shockingly close to a "Space Oddity"-era Bowie sound. Super cool.

Did I mention the Fed+ is a preamp as well? With the ratio knob all the way down and threshold fully clockwise, you have a really nice preamp with 22 dB of gain. I've gotten absolutely killer things to happen with mics that are hot enough for this gain level on loud sources. Set the controls as described, plug- in your favorite tube condenser and place anywhere near a loud drummer - instant rock action!

The Fed+ really has a way of flattering almost anything you throw at it. The only thing I couldn't get it to do was abuse things. The Fed+ is too classy for this! It's like asking the Queen of England to slap a cop. In a word, it's very polite. My only gripe? I wish I had two. This would be my go-to drum/vocal/mix-bus compressor! Talking to TJ about this thing, he's thinking of adding a linking feature or doing a stereo model. The bottom line is that the Fed+ is an absolute steal. There has been nothing it hasn't made sound great. I bought mine at a time when I was fairly broke due to some remodeling, and January in Detroit isn't a lucrative time for studio owners like me. Much to my accountant's chagrin, I will be getting a second unit first chance I get.

($1499 direct; -Chris Koltay, 

Tape Op is a bi-monthly magazine devoted to the art of record making.

Or Learn More