Altec 1569AT 6L6 Monoblocks

If you went to the movies (or to high school) in the US in the 50’s, 60’s, or 70’s you’ve probably heard amplification like the Altec 1569AT below. These are rack mounted 80-100 watt per channel 6L6/EL34 PA amps typical of thousands that graced many a gymnasium, school auditorium, church or theater throughout that period. And in fact the pair below came out of a private school in Maryland. On loan from a very generous local audiophile (thanks George!), these antique industrial beauties proved to be quite good performers in my room, and on the Lii Audio F18 baffles these big monoblocks light up the music in a way the small single ended amps just cant seem to manage.

Appearing in issue 7 of Vacuum Tube Valley magazine back in 1997, these amps have had a following since they were first introduced in the 50’s and became collectable, with many updates and mods to get the most out of these primarily midrange focused amplifiers. With a heavy duty rack mounted construction, and in some cases Peerless transformers, these are high quality amps that perform well beyond their somewhat pedestrian PA pedigree, and they have found a place with some of the more adventurous members of the hifi community. This pair were rebuilt by local Baltimore tube guru Nikola Nikolov. Brought back to spec mostly true to the original circuit, they perform flawlessly. George and Nikola dropped these off at my place and I spent most of the summer of 2021 with these old amps running up against everything I have on hand.

With a spacious and energized presentation, the Altec 1569AT really grip the speaker cone. 80 watts per channel is a lot of tube power, and these are the largest power amplifiers that I have had in my rig so far. When first firing up the Altecs, taking the place of a small 2 watt single ended amp, I was struck first by how quiet the Altecs are at idle, which I didn't expect. When the music starts, these amps effortlessly create a huge seamless space that is just full of nuance and depth. Starting with something simple, Jeff Beckley’s version of Just Like a Woman, the Altecs throw a life-sized Jeff Buckley on stage in the middle of my room, seemingly in real space, feeling more like you are sitting onstage just in front Jeff and his Telecaster. Very pleasing. Moving on to something heavier, Rush’s Necromancer on LP, this old favorite builds and builds, exploding and fading. Through the Altecs, those complex transitions are always coherent and present. When I hear Rush, especially the older stuff, I always find myself wondering “How can just three guys make that much sound?” The Altecs render them perfectly, with no hint of running out of drive on the heavy parts, and light as a feather on the gentle strokes.

In comparison to the finest of the single ended amps on hand at the time, namely a Triode Labs 2A3 integrated and an Elekit 300B, the Altecs fall slightly behind in almost every category. But not by much. The DHT tubes do nuance and detail and soundstage just a little bit better. Reality, or suspension thereof, is a closer call. The sheer power of the Altecs seems to give them the upper hand in cohesion, and they outperform the 2A3 and 300B in “presence” factor.

This pair of monoblocks has been a real pleasure to experience, and if I had the room I would very seriously consider keeping these or finding another pair. They exude a coolness factor that is very pleasing and their industrial no nonsense style really works for me. The sheer power of 80-100 watts of 6L6/EL34 has been eye opening, and is something I did not expect to enjoy so much. These are not so common on the used market, but do pop up now and then. If you have the space, and can find a well restored pair, these old PA monoblocks could be just the ticket for a 1960’s teak or mahogany paneled, rack mount living room system that would knock the socks off of everyone who hears it. Highly recommended!

These have seen a lifetime of use! Simple, classic Altec. I can see why Ken Shindo liked the color so much.

Everything about these amps is overbuilt, like a dump truck. Those are dual 5U4 rectifiers on the side.

Look at the size of the power transformer. These are heavy amplifiers.