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.

Onkyo 8CX-A1 Coaxial Speakers

Slowly this audiophile is exploring the idea of open baffle speakers, I have been collecting rare and one off coaxial and triaxial speakers.

This pair of super rare but in mint shape Onkyo 8CX-A1 speakers were purchased on eBay. They flew over from London England to be part of my world. The workmanship and attention to detail is not found in modern day speakers from China.

Onkyo has a history page in where the original 8CX range was born in 1956.

The plan is to have these installed in an open baffle system with a Foster 10" alnico woofer for the bottom end from this pair of Noresco NEC-571 speakers. There is also a crossover in this speaker that will cross to the Onkyo around 600hz. At 100db efficiency these will suit the tube amps perfectly.

More to follow on the evolution of this project.

Noresco NEC-571 Speakers

I came across another pair of Noresco speakers, the NEC-571. Super heavy, solidly built with a real wood veneer.

Instead of using Isophone drivers, this unit uses Foster drivers. The woofer seems to be Alnico, the tweeter seems to be a full range 3" driver that acts like a mid range/tweeter, it has an open back on the casket but its own separate box inside the speaker.

These speakers sound pretty solid with deep bass from the 10" woofer. The speaker box is an acoustic suspended design.

Efficiency is pretty good as they sound pretty loud on the tube amp.

They remind me of the ADC 303AX speakers that were featured here a few months ago.

The cabinets sanded out the blemishes pretty nice and a coat of Circa 1850 Terra Nova oil brought back the luster of the Walnut. I pulled the old faded speaker cloth off to reveal the drivers, it needs to be replaced.

A much different offering than the Noresco NE-561 speakers featured here early. These have more bass but not nearly the sound stage as the NE-561's.