Suggestions for Foster Loudspeaker restoration project?

[DanielMac]

I scored these Foster loudspeakers at an estate sale a few years back. I thought they were end tables. Surprise, they’re speakers.

They sound decent enough as is, but I’d like to try improving them.

This will be my first time working on a speaker, so I appreciate any conversation, tips or ideas.

I initially thought I’d add some binding posts, replace the capacitor and add insulation into the cabinet.

What else can I do while I’m messing around in there?

 

[bowtie427ss]

How did you identify them as Foster?

The tag is from a Packard Bell console. At least some of the driver load is consistent with late 60's Packard Bell.

 

[DanielMac]

Foster is the name on the mid range driver and the horn. Thank you for the Packard Bell identification from the tag.

 

[bowtie427ss]

I'd opine that the Foster units were OEM'd to a US manufacturer. Zenith and others used those Foster horns.

Since the Packard Bell? tag indicates a powered unit, it seems possible that rear panel has been transplanted from elsewhere?

Since there's not a conclusive pac bell ID anywhere, i still say the name with some reservation/question.

Do you have a pair?

The louvered fronts are very Magnavox-ish. But, i have never seen them on a separate speaker cabinets, just the speakers attached to/part of the main console.

They're interesting. Maybe start with some damping on at least 3 side of the cabinet.

 

[DanielMac]

Yes, I do have a pair.
The louvered fronts are my favorite part of the package.
I have some foam egg crate material I want to use to dampen the inside.
Is it worthwhile to replace the capacitor and wiring between the horn and drivers?

 

[goodolpg]

The wiring is probably fine. Replacing the cap (only 1?) should be cheap.

 

[DanielMac]

One cap per cabinet. I have the stereo set.

 

[goodolpg]

Will still be cheap. Depending on where you buy the shipping could cost more than the caps.

 

[DanielMac]

December Update: I’ve replaced the capacitors and attached the bare speaker wires to a pair of binding posts.

With the time inside these cabinets, I feel safe saying these cabinets were once part of a console unit. There are very inconspicuous veneers on one side of each speaker cabinet. Also, The plinths each speaker stands on look like they were added later.

Can anyone lend me some experience or thoughts to help me decide on how to damp the cabinets?

The first question is whether or not to completely seal the cabinet. You can see the large hole in the bottom of the cabinet. I’ve read some posts that talk about vented speaker cabinets, but I’m not sure if it’s necessary to leave those open for these systems.


Also, bowtie427ss suggested damping at least three sides of the cabinet. Is that the top, bottom and rear?

Is there a plus, minus or possible null in applying something to all sides? What about stuffing it with some kind of filler?

It’s been a fun first project thus far. And I want to say it sounds better already.

Thank you in advance for any suggestions and advice

 

[RVT1K]

Most of your questions would require specific info on the woofer especially the sealed vs. ported.

Adding bracing to the cabinets will help.

But it sounds like you're very willing to experiment. Everything you have mentioned has the potential to change the way they sound but making any predictions will be mostly speculation.

 

[DanielMac]

January Update:

I took your suggestions and added bracing to the cabinets. Although I didn’t take the time to a/b test them with and without bracing, I perceived a decent improvement with that change. It was fun to do and the pride factor probably bumped up the sound quality in my mind.
This article helped me wrap my mind around the process of adding braces to the cabinets: https://www.humanspeakers.com/howto/bracing.htm
(I have a pair of EPI 100s that I want to restore sometime soon, so the human speakers site has been a great resource)
Now I’m experimenting with different damping materials and damping configurations. I think the differences will be very minute from here on out, and it’s getting a little harder to put off the other priorities and honey-do items.

 

[RVT1K]

Nice!
I had stumbled on the Human Speakers website a few years ago and came close to pulling the trigger on building a pair of his 88-41's. Ultimately, I had to get real about my woodworking skills (more suited to framing) and lack of decent woodworking equipment.