Zenith Allegro 3000 Speakers

A long time ago I trash picked a pair of old Zenith speakers, I don't think I even paid attention to what brand they were when I first got them, all I new was that they played and filled the need for sound in my shop.
I ran them off an old Harmon Kardon 730 at the time. Later I upgraded to an HK560 receiver. They always sounded good but were butt ugly. The cabinets were OK but the grills looked like they were used as scratching posts for a long time. In the process of moving stuff around I came across these speakers which had long since been put away in the storage room. Wanting to see if they still played I hauled them home, and to my surprise, they still sound good, better than just good, especially compared to many other speakers of that era.
I removed the back of each speaker to make sure I hadn't brought home any hitchhikers from the shop at work, and was surprised to see the size of the woofer magnet and that its got what appears to be a Foster horn tweeter or some sort. I replaced the single 4uF capacitor in each crossover and did away with the direct wire set up in favor of a recessed terminal plate.
I then went to work on figuring out what to do with the grills, the originals were too far gone, even the plastic mesh they were pressed out of was cracked and falling apart.
I decided to make a pair of simple wood grill frames similar to what other speakers used back then. Not being able to get decent 3/8" plywood, I got some birch/oak 5 mm plywood and glued to sheets together. I made a paper template first and transferred all the speaker and bass port locations to the new grill panels. After cutting out the holes and sanding everything smooth, I painted the panels flat black so they wouldn't show through the cloth mesh.
I thought about making the grills similar to how they were originally with the bass port protruding past the grill but decided on a cleaner look, I cut the bass ports back so they could fit under the grill, and cut the emblems down so they could be affixed to the front of the grills.
The bass port extents right up to the grill cloth, the grill cut out fits over the extended port.

Wanting these to look at least somewhat period correct, I hunted for some textured cloth, but found nothing locally or online that fit the bill. What I did find was that Walmart sells cheap drapes, and the material was perfect, (One style even supplied me with a near match for the grills on my vintage KLH 17's).
For under $5, both grills, and probably two or three others will have new grill cloth.

I attached the grills via Velcro tabs, much like the grills on my Avent 4002's. A quick cleaning, some furniture polish, and they look good again.
Sound wise, these are somewhere between my old KLH speakers and my old large Advents. The Advents have a bit more bass, but the Zenith speakers hold their own. I had really forgotten how good they did sound, especially for basically being department store fare back then. (Both speakers appear to have date codes stamped on the inside of the cabinet which read 8/73, which would probably mean these were new in or around 1974.
They aren't anything super fantastic but they aren't bad at all, I actually prefer their tone to my OLA's. They don't compete with my Boston A400's or T1000's but they aren't hard to listen to either.
Being these are 16 ohm speakers, they can be paired with another pair of speakers which compliment them. They sound great paired up A/B with a set of old Avid 101's I've got here.

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I found the drapes by chance, I had gone to several material stores and none had anything like what I wanted. Besides, the last grill material I got online faded from black to purple in less than a year. Walmart here recently added a sewing and material section, I was looking there for something suitable but found nothing, I cut through the home furnishings to get to the paint section to grab some contact adhesive and spotted the drapes. The texture of the one type was a dead on match for my KLH 17s. After looking through all the choices I chose the texture black styel to give it an earlier look.
The drapes should have decent UV resistance considering what they're intended for, but they were cheap. For $4.39 I got roughly 2.5 yards of material. Its really thin and light passes through it easily so sound shouldn't be impaired by it either. Its far less restrictive than what was on these, which was mostly a hard formed plastic mess with black cloth vacuum formed to it. If the old grill backing was in better shape I may have tried to just recover it but it wasn't salvageable.
They look better like this anyway.
 
I have a pair, and the drivers are not terrible. The cabinet is a weak point and could probably benefit from some internal bracing.
 
I gave a pair to my nurse aide who visits me three times per seek. Regret it, because she gave them to her boyfriend. With a Lepai amp. She never even hooked it up.
 
The cabinet is made of 3/4" particle board, its pretty rigid due to its smaller size. I was going to add a cross brace but didn't see the need. These things are pretty heavy. They're double the weight of my similar sized KLH speakers from the same era, and only a few pounds lighter than my Advent 4002's.
The Advents have them beat due to the size of the woofers but the tweeters on the Allegros hold their own.
The only functional change I may have made is by removing the badge from the front of the bass port. I cut away the cross brace inside the port and made it an open port, covered only by the grill material. Since the port installs from the front, (its anchored inside with speed nuts and foam), it protrudes about 3/8" forward, thus the grill frame had to accommodate this. I was originally going to cut the grill and install the port through the grill just as it was with the original grills but that would mean I'd have to open the back of the cabinet to remove the bass port first just to remove the grill.
Being that these are 16 ohm, I'd like to find another set and try a pair of these stacked, or any other 16 ohm speaker in that configuration. They sound great combined with my Avid 101's, which are acting as a speaker stand as well right now.
It had been years since I heard them, but I remembered they would really crank out some music in the shop, I was pleasantly surprised when I heard them all cleaned up and with new grills on some better equipment in the house.
 
Thanks for the memories. I distinctly remember the Allegro series. Now you've given me a new mission- what a pal!
 
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