Unitron Speakers

Unitron speakers? Huh? An easy thrift store pass by..... It is what is in the box that the treasures can be found.

This pair caught my eye as the cabinets are in pretty good shape and made of real wood veneer, they do need a bit of sanding and new polish, that is easy work.

I opened these up and found a 10" Coral woofer and Coral Alnico tweeter, I figure the cabinets and the drivers were well worth the low low asking price.

My plan was to find a new home for some 10" Foster Alnico woofers and a tweeter of some sort, these boxes would fit the bill.

 I got these home and listed to them with the Coral's in them, boomy, boxy sound was all I heard. The Q's are too high from the woofer for this box. I pulled them out and inserted the Foster 10" Alnico woofer and a Radio Shack 4" Alnico full range speaker, crossed over with a simple 22uf cap around 900hz. Now these speakers sound delightful, like amazingly delightful.

 

Like amazingly delightful, I am going to do more finishing work on them but I have them up and running and I like what I hear.

I mounted the Corals on a spare baffle board that I had around and gave these a listen....OMG these on a baffle are a completely different speaker. Super efficient, the high Q's add beautiful sounding bass for its size of the woofer and the mids and highs are dreamy delicious. Just as I suspected.

New baffles will be made for these and I will offer them up for sale in the near future.

Foster Open Baffle Speakers

The latest open baffle speakers I have put together is a 3 way Foster driver speakers. The donor driver came from a pair of Noresco NEC-571  plus a horn tweeter that I picked up from a set of Zenith Allegro speakers.

This project turned out to be spectacular with the push/pull tube amp, almost in the league of openness and fullness as the Speakerlab Super 7's, almost. The Super 7's are really an amazing loudspeaker.

 The original Noresco speakers used a 10" Foster 25E33 alnico woofer with a massive magnet assembly crossed over to the Foster 8F3 three inch full range speaker. The original crossover was used as the crossover point between the woofer and the full range driver is around 650hz.

A foster horn tweeter was included to handle the high end as I found the 8F3 seemed to roll off in the highs.
A 2.2uf cap was used with a crossover point at 9000hz, it seems to have added the high end depth and sizzle that I like.

This combination came out way better than expected. Bass is full and clear, the mid range from the 8F3 is luscious and smooth, very deep and wide. the horn tweeter takes care of the highs in spectacular fashion.

Before I started this project I had an idea as to how this set up would sound, but it came out way better than I expected.

If this is what open baffles are supposed to sound like, then I am a believer now.

Aesthetics came out beautifully with the dark mahogany veneer.