Tube Preamp Reviews

At the back of the chunky, wide, case you'll find only single-ended connectors, plus a standard 15A IEC mains in. The five line-level inputs are all electrically equivalent to each other. Next on the rear panel are the EPL 1 and 2 ins and outs, on RCAs. I never used 'em, but you can for tape recording. Or they can be pressed into service as two additional line-level inputs!

The preamp outputs are recommended for amplifiers with at least 20k ohms or higher input impedance: Krell FPB 350Mc, check; Cary V12, check; Forsell Statement, check; Linn Klimax (10k ohms), never mind.

Remember to compensate for the 16LS's polarity-inverted output. I usually reversed the spades at the speakers. As for actual physical placement of the 16LS, this involved settling it into my current system, both electrically, you might say (a choice of impedance-correct amps, for example) and physically; ie, that upon which the preamp was plonked for the purposes of gauging its sound.

My current reference in such matters is the aforementioned and extremely effective resonance-control system manufactured by Silent Running Audio. As you'll read in a future Follow-Up of the Lamm L2 line-stage preamp after "factory-approved" additional treatment with internal Silent Running damping materials, bases, and isoDomes, it became all too obvious, once again, that proper control of resonances is of paramount importance to good sound.

Of course, for thoroughness, I at first listened to the 16LS right from the wall on a PolyCrystal stand with no footers of any kind. As always, after a period of time, I began tweaking until I got the sound just so, then whipped out the laptop and...notes be taken.

For the major part of the evaluation, I relied on the Cary CAD-280 SA V12 power amplifier. It was spectacular with the 16LS, and fitted more closely, I imagine, the profile of the typical ART/16LS customer. The Krell 350Mcs, while not bad-sounding, eliminated themselves almost immediately—they don't even have single-ended inputs! I have excellent XLR/RCA adapters from BAT, but the 350Mcs simply didn't sound their best. Forget the Linn Klimax—electrically, there'd be no chance that the bass wouldn't roll off early, as its input is a lowly 10k ohms. The Forsell Statement sounded fine as well, but these days I prefer the Linn and the Krell for solid-state.

Before falling into the sound, I have a small but general complaint about the 16LS's user interface. First, there's a "quirk" of the control circuitry that I just didn't like. Suppose, during a party, you have the preamp turned up way loud—and the sumbitch will play loud, as do most single-ended "unfollowered" zero-feedback preamps. Then, at the end of the evening, still in a rather shattered state, you decide that, rather than turn the volume down before muting and passing out, you'll just whack the Mute button on the remote, shut off the amps, and have done with it.

Then let's imagine that, having regained your composure the next day, you want to soothe your aching head with some music, and you head for the system. When you power up the 16LS, it goes into auto-mute function for 90 seconds before suddenly engaging. But when it does engage, it'll be at the last volume setting you used, and there's no way to adjust that until the preamp unmutes itself. Okay, no problem—if you're doing what you're supposed to be doing, your amps should remain off while you kick-start the preamp. But just keep that fact intact in your foggy little audiophile brain. Because I didn't once, and ya-hoo—we musta been havin' fun the night before!

And now...
...the moment you've all been waiting for: How did the Conrad-Johnson Premier 16LS sound?