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Norman Lab circuit breaker replacements?

avguytx

avguytx

Lunatic Member
Ok....I officially hate these *&^## circuit breakers on my Model 9's. They continually drop out and have to be fiddled with. I guess I'm going to have to break down and take them out to figure out a way to clean them more so than I already have with Deoxit. That or just get rid of them entirely (which I may prefer) or replace the breakers with fuse holders in the same opening. I'm sure they could be replaced with something else if there was known information on what ratings they are. Basic Blues? John_John30? Any ideas?

Other than than, I love 'em. :D

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Hey Kip
My older style model 9s have fuses (2 each) and are 3amp. But my crossover construction is quite a bit different from yours.
Thats about the best insight I can give.
It seems to me that if you know the amperage that trips a functioning breaker, you should be able to replace them with fuses.
martin
 
That's what I'm thinking, too. I will most likely bypass the circuit breaker on the woofers....I don't think that's needed as much as it is on the tweeters. I can't recall any other speakers in the last 30 years I've messed with audio that had breakers on the woofers.
 
My Tens have a similar crossover design, and I have a similar problem with the circuit breakers. I laid them over face-first on the carpet (carefully) and sprayed Deoxit down the shaft of each one a few times while resetting the breakers over & over. I would push in and hold, then slip my finger off causing the spring to slam the breaker into rest position. This helped a lot but I still have to reset every now and again, using that same technique.

Do yours have the original terminals? And is the barrier strip across the top used for biamping? Is the bulb for extra tweeter protection? Do I ask a lot of questions?
 
No....I changed out the original crappy terminal strip thing they used and installed binding posts so I could use banana jacks for easier swap outs. That barrier strip always raises those questions about biamping and from all I've gathered, biamping wasn't done on these. But I'm not the authority on that. Yep...that light bulb is used to dissapate extra energy and is for added protection. Not sure how many home speakers used that thru the years but the bulb was pretty popular for a lot of car audio separate systems crossover networks on the tweeters.

A lot of questions? Of course not! That's one of the great parts about this forum!
 
avguytx said:
No....I changed out the original crappy terminal strip thing they used and installed binding posts so I could use banana jacks for easier swap outs. That barrier strip always raises those questions about biamping and from all I've gathered, biamping wasn't done on these. But I'm not the authority on that. Yep...that light bulb is used to dissapate extra energy and is for added protection.
Click to expand...

You know, the last time it was brought up I thought that barrier strip wasn't even connected, (idk what's me problem here :drool:) but looked again at your pics- which is the exact same layout as mine, it looks like it is totally connected and biamping is totally possible. I'm curious now why no mention was made of it in their literature (that we have seen)

Also agreed on the :thumbsdn: on woofer protection. That rating may also have been posted at one point, but I can't recall. I think it was decided by consensus that bypassing them would not be any great risk ymmv naturally
all responsibility void where prohibited by common decency, etc.


Also, I just looked up a recent thread where Martin posted pics of his 9's, which are 1st gen, and they do not appear to have the internal wiring for bi-amping, so I'd also guess the bar is not there on his either.
 
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Yes John your right.
In fact, of all my Norman Labs (9's 10's and Series 83's) none had the terminal strip. None have the circuit breakers and only the series 83's have a light bulb.
The plot thickens.
martin
 
avguytx said:
Ok....I officially hate these *&^## circuit breakers on my Model 9's. They continually drop out and have to be fiddled with. I guess I'm going to have to break down and take them out to figure out a way to clean them more so than I already have with Deoxit. That or just get rid of them entirely (which I may prefer) or replace the breakers with fuse holders in the same opening. I'm sure they could be replaced with something else if there was known information on what ratings they are. Basic Blues?
Click to expand...



I officially hate these *&^## circuit breakers every 20 minutes or so. :mad:
You never know if the tweeters are at the optimum until you push it just to be sure.


Steve
 
I hate second-guessing these speakers so much... because I've always liked them. But I just came up with another question: on a 2-way design why are level controls on both the woofers and tweeters necessary?

On older 9's, I was told, the woofer control would switch off the rear-firing woofer, effectively using it as a passive radiator. Furthermore, some out-of-phase voltage was applied to further "stiffen" its action.

Does any of that sound familiar?
 
Kip, I don't know if you can read it but it looks on this pic of mine (with the old caps) the reset fuse for the woofers has a 2.5A and under that what looks like a 4. I can't quite read what's on the side of the tweeter reset.

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Also, @beans, my best guess on the woofer control toggle is that it does cut out the rear-firing woofer. Acting as a passive wouldn't make sense since passives are a whole different design and can have just as much punch. Plus all the insulation.
 
Hey Kip
whats the model # of the your phillips tweeters. My NL83's use a 1 amp auto reset fuse and bulb to protect the single phillips (too many #'s on mine to guess which is the model #) in the NL83's
martin
 
Any luck finding a replacement? I have one (for now) Model 8 that is exhibiting similar problems, cuts in & out. Would like to drop in a replacement instead of bypass entirely, but I tend to be a purist so...
 
I had some beat to hell later Model 8's once upon a time for a shop system. I ended up bypassing the tweeter breaker on one and A/Bed them. The breakerless one was a bit brighter up top. I don't know if it was necessarily a good thing considering they were already a pretty bright sounding pair of speakers, but take it as a note if you decide to bypass them entirely.
 
I finally got around to bypassing these damn breakers today and I am thoroughly satisfied that they are out of the circuit now. :D It was funny, as I was changing the connections on the first speaker, the other one was playing and was cutting on and off on both the woofers and tweeters. I was saying to it, "you're next, bitch". hehe. Good to go.
 
And guess what I found by researching the brand and series on the circuit breakers. :D

Tada!!!

Here's the exact replacement....screwdown and all for $10 each. It also has the exact same patent numbers, too! :thmbsp: Here's a picture of it....

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At a quantity of 10, there's a price preak to $7.50 each. lol

Here is another one but the breaker value is less....but they are only $.20 each! (yes...20 cents) They might possibly work for less money.

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And from listening to The Eagles - Hell Freezes Over for the last hour or so, I can honestly tell you that the bass sounds MUCH stronger and the mids and highs really opened up. There had to be a good bit of resistance in those breakers. I highly recommend you bypass the breakers if you are running good clean power and are not a major cranker (at least into clipping) or put new breakers on yours! (or replace the breakers with a fuse holder instead)
 
avguytx said:
And from listening to The Eagles - Hell Freezes Over for the last hour or so, I can honestly tell you that the bass sounds MUCH stronger and the mids and highs really opened up. There had to be a good bit of resistance in those breakers. I highly recommend you bypass the breakers if you are running good clean power and are not a major cranker (at least into clipping) or put new breakers on yours! (or replace the breakers with a fuse holder instead)
Click to expand...

Wow, you are a hero. :thmbsp::tresbon:
I agree that the bass somehow suffers when the breaker starts to go.

Time to get off my ass and fix these once and for all. Thanks again.:thmbsp:


Steve
 
From start to finish on both speakers, it took about 45 minutes. Man, why didn't I do this sooner? It was an afternoon of musical enjoyment....like they were finally unleashed.
 
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