Altec 1592B Mixer Amplifier

These aren’t exactly HiFi. But if your a Altec fan you might appreciate these. I rescued them from a trip to the dumpster a couple of years ago when my wife’s company was upgrading there 1960’s PA system.
there decent little mixers for being as old as they are. I took two of them and wired them up so I could have 5 channels in stereo.
I guess the VU meter was a option you could get them with or without. The ones I have have them.
Something thing I thought was cool on them. Each input has a socket for a transformer to go in. And you can get different style ones. Like one for line level and another for a mic input. Those transformers probably cost more than the mixers. At least some of the rare ones. I have some of the red line ones and some black line ones and some purple mic ones. I think the red ones cost $30 or $40 but have seen go as high as $70 and the black ones where $20 or $30 and the purple ones I don’t think were more than $20. It adds up when you have to install ten of them just to get the mixers to work.
Both of the mixers I have are 1592B’s but have slight differences on one of them for each channel you can adjust the gain with the knob but then they both have switch’s below the knobs and on one mixer the switch is a three position one with stops on 0db, -10 and -20 on the other mixer it looks like the same switch but it doesn't have stops it’s variable from hi to low. The VU meters are about 95% the same with just a couple aesthetic differences.
The front panel unscrews and folds down to give you access to all the internals.
Anyway I thought they were cool. Maybe you will too. I’ll attach some pictures below.