Norman Laboratories Model 9s Inherited

[dsmflow]

Greetings audio goers,

I have recently come into ownership of a pair of Norman Laboratories Model 9 speakers. They had been sitting in my grandmothers house collecting dust for over 39 years, at least...(my entire life). I was actually born in Norman, OK and joked about Norman Laboratories being in my hometown - not actually knowing that was the truth I am not exactly sure how these were acquired. My grandmother did professional glasswork, etching, stained, foiled, and she was the creator of the infamous stained glass that sat over O'Connell's in Norman for decades ... and it was rumored these pair were payment for services rendered (probably some family hyperbole at play as I had never seen or heard this woman be remotely interested in audiophile *anything*).

The things that stood out to me initially...

The tweeter baffle is a 1/16" thick sheet of stainless steel with a 3M hi-tak spray application maybe? Something to promote adhesion, rigidity and dampening.

The front grill is formed MDF with the same sprayed application as well as each woofer baffle is reinforced with two 1/8" MDF rings laminated together for even more rigidity! Sadly, this ring was SO rigid it tore away from where it connects the frame to the surround on one of the woofers; the screw had been driven in almost sideways that it tore when unscrewing. However, this woofer seems to be the only visibly damaged one. The rubber surround was sliced badly as well.

The acoustic foam inside each enclosure appears to be fiberglass. Don't forget your Tyvek!

The crossovers are still inside the heart of fiberglass...but I suspect they are working just fine. Those pesky protection mechanisms though ... must go!

The tweeters are in working order.

5 of 6 woofers are visibly undamaged.

1 of 6 woofers badly damaged - complete refurbish will be necessary.

Back in November 2023 a friend gave me a Sears Solid State AM/FM, 8-Track, BSR turntable and I suppose I will be using it in the short term to drive these things. It drives decently on FM, but lacks any real power or punch with the phono driving.

Needs are as follows:

Small Amplifier recommendations (I have a Dayton Audio powered subwoofer and do like their amplifier offerings in small form factor)
Cross-over facelift; replace parts or overhaul altogether?
Speaker Protection mechanism ... is it necessary - specs of original components? I have serial numbers on the woofers and tweeters - Creedence and Phillips respectively...do we have numbers on ratings handy? I don't expect to be pushing these to their max, but we DO have to sound test, right? Right?
Contact Speaker Dave for sourcing replacement woofers or repair/refurbish the originals. The one woofer I had to fiddle with is in pretty bad shape but I think it can be saved. The rubber is still attached to the cone just not the frame.
Remove fiberglass "foam" inside the enclosures in favor of a less hazardous material, recommendations there? I used that pillow stuffing from the craft store for years in most of the car audio installations I did.

Budget friendly is preferred, but I understand not all parts are created equal. The only time I would go after a bad resistor is on a Roland TR-808. I am comfortable soldering if that factors into cost at all.

I made an album for the photos I was not able to attach.

Regards,
dsmflow

 

[swechsler]

Assuming it's still holding its shape, I think I would just keep the fiberglass in place. While it is annoying to work with, once you're done with it, it'll be sealed back in the cabinet. Recap the crossovers; the rest of the components should be fine (although you can measure the resistance of the resistors while you're in there). I'd probably replace the circuit breakers with standard fuse holders; you'll probably have to drill the holes larger. Hopefully the values will be stamped on the backs. And while you're at it, replace the input terminals with a decent set of binding posts. Regarding the damaged woofer: if you push in on the cone, can you hear the voice coil scraping? If not, even with the creases in the cone, if it's still solid, replacing the rubber surround will probably be sufficient. Or you could keep an eye out on ebay for a replacement.

 

[doug76712]

These are certainly worth the time and effort. I'm far from an expert, but it took me very little time to bypass the circuit breakers and replace the capacitors in a pair I have. If you plan on driving them hard, the fuse setup swechsler recommended is a great idea. You already are aware of Dave at Speakerworks in Tulsa, and that is where I'd look for any actual driver repairs if needed. Maybe look for a receiver or amp in at least the 50 wpc range to drive the Model 9's because while they aren't terribly inefficient, they do need some guts to reach their full potential. As long as you have the floor space and room size to accomodate them, your Model 9's will be a very difficult speaker to upgrade. I can't see in your photos, but the glass is almost always missing on Model 9's that I see. It fits edge to edge in the recess on the top and is a dark, almost black smoked glass, maybe 3/16" in thickness. Finish up by applying some Howard's Feed-N-Wax with 0000 steel wool and a new black grill cloth and you'll be ready for me to come get them.

 

[dsmflow]

I was able to pull the entire crossover panel board out. I have a good friend who is a master electrician and has some thoughts on the design, haha, but he is going to help me test the bad pieces and replace the parts as we go. All of the parts are identifiable, so, thank you! The inductor wiring from the birdseye view was a little perplexing, but it makes sense once you get the underside view.

The room they are in is roughly 21' x 22' - I am not sure if opposing on a similar wall is too much space between them for fidelity, but any close and you won't be able to cue on the pool table without hitting them.

My grandmother, ironically, ONLY cared about the glass on these things - as it was her profession after all. I still have the originals ... and I can hear her from up above telling me they need Windex! They measured at 1/5th of an inch thick, yes 1/5th on the nose. 14 inches wide and 11-1/2 inches long.

I am missing a badge on one of the covers, but it might be easier to just snag 2 matching ones.

The veneer seems to only be single sided with some of the finish or stain used dripped on the inside. I absolutely love that. The veneer peeling is unfortunate, but I can make new shoes for them - those don't seem to impact the overall chamber volume.

Updated with some photos of the crossover now that I have it out, and the project space; excuse the mess

 

[dsmflow]

More succinct view of the parts inside the actual crossover. Also, anyone know the nominal ratings for these woofers?

The torn rubber woofer is definitely salvageable - the major damage was done during unmounting it - I chose to start with this one in particular because it already had a slice in the rubber surround. It moves freely, responds like it should, in my opinion. My experience is limited to a couple summers as a youth doing quick and dirty car audio installs out of a flea market ;D

 

[avguytx]

@dsmflow Main things that stand out for me having owned numerous Norman Lab speakers including Model 9's.

1) Bypass those circuit breakers as they are worthless at 40 years of age.

2) Replace those black caps with the red ends with new reasonably priced poly caps and call it good.

3) Clean the switches good with an electronics contact cleaner. Deoxit is ok if you have it around.

4) For any indepth work needed, like the woofers, contact Dave Miller at Speakerworks in Tulsa, OK at 918-664-6299 as he knows all things Norman Lab and is the person who bought out all of the remaining parts inventory when they folded. He doesn't have much for parts anymore but he would know best what to do and make them right.

5) Put a real amp on them and enjoy.

I think all I ever did on mine, as most all were Walnut veneered cabinets (with a few small solid pieces) was use Watco Danish Oil on them and that was it.

 

[doug76712]

Those speakers will be fantastic in that large room if paired with something adequate to drive them. If you can get them off the wall a few feet, you can even run the rear woofers with great results. Kudos to grandma...it's a bonus that you have the glass!

 

[Blue Shadow]

How bad is the bad woofer? Is the surround damaged beyond repair? Many here refoam speakers. Surrounds are frequently made of foam so that name stuck cause the rubber usually doesn't need to be replaced.

Dave at Speakerworks in Tulsa is the Norman guy if you need to talk to someone about the best way to go forward.

 

[dsmflow]

The surround peeled up off of the framing - and has a very small tear in it about 3/8" long, straight, clean cut it seems. For now it is just holding its place in the cabinet, disconnected and sealed.

I've bypassed the reset switches and moved the rear facing woofer into the bottom position of the 2nd speaker since we're so close to the wall, firing it makes little sense for now.

My electrician friend says we can build an amp better than what I can buy online, so I told him challenge accepted. If things go well I will post an update. If things go poorly, I'll CERTAINLY post an update. Cheers!

 

[Blue Shadow]

You can reglue the surround and fix that small tear easily. Use proper glue and things should be right.

 

[dsmflow]

Hiding conspicuously in the corners - at 65% on the Denon the neighbors already getting their phones ready with no amp inline yet. Aww hell.

 

[avguytx]

Again, call Dave Miller at Speakerworks and see what his recommendation is with the torn surround. I've repaired various rubber surrounds (from the back side) using a black rubber cement, which is what Dave had told me years ago. If the rubber surround has lifted up from the frame, you can use something as basic as Alene's Tacky Glue and will work quite well.

Here's some from Amazon that will work great. This is what can be used to repair the ripped surround and glue it back down. I don't recommend playing them without being attached.

 

[dsmflow]

@avguytx I agree, playing a woofer without it's surround attached to the frame is not ideal. So, I am not playing them without it being attached. I suppose it's not super clear when I said I swapped the woofer with the rear-facing one and left the bad woofer disconnected (toggle switch in the back). So, we're operating with two enclosures, each with 2 firing woofers and 3 firing tweeters (I think I read someone mention the rear facing and bottom seated woofers are of similar build and the top-most woofer is slightly smaller..so I swapped like for like it seems). I spent a lot of time doing car audio installations, so I am not scared to tear things apart and get them working. I do want to maintain the original feel of these, though, so I won't be gutting and replacing for anything other than the OEM woofers. I will use better caps, but leaving the inductors as is, I imagine there's some falloff from the tweets at the crossover freq that is rolling into the upper woofer for that warmth. The bypass has been completed on the protection fuses and without an amp they sound pretty good - can't wait for more power. I've got no real push to get the 6th woofer fixed at the moment. I've also got a 15" 200W Daytona Subwoofer in the same room. We're in a sweet spot right now.

 

[Blue Shadow]

is the rear woofer open to the front woofers? This would cause the front woofers to be 'driving' the rear woofer even if disconnected with the pressure changes in the cabinet as the music plays. Would cut the bass and allow the front woofers to move too far, as I think these are acoustic suspension speakers.

If the rear woofer is in a separate compartment, should be ok leaving a loose surround woofer in place.

 

[avguytx]

Those woofers all share a common cabinet; they are not a divider. If you turn the back one off, it still moves and is acting as a passive radiator. At least they did in mine. It's just an acoustic suspension cabinet...nothing fancy going on in there.

 

[dsmflow]

Yep - I wasn't pushing them very hard until I procured a bottle of tacky glue to reattach the rubber to the frame, and repair the small cut. I've got everything cleaned up, reattached and the small cut has been fixed. Now time to build the amp and really test these things. Thanks for the suggestions!