• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Help with Norman Labs Model Ten

undergroundr

undergroundr

Active Member
After noticing a channel imbalance and poor imaging, I found that I seem to have a blown upper 10" driver in one of my Model 10's.

Using a multimeter, it looks like continuity is good from the terminal to the voice coil.

I've switched the driver to my other working Model 10 and it doesn't wake up there either.

The butyl surrounds are solid, and the signal passes through from the upper 10" to fire up the lower 10" properly when all terminal wires are attached.

Anything else I should look for? What's my next step forward? I know "qualified technician" and "replace the driver" are the best answers, but I'm utterly penniless at the moment and am interested in learning anyhow. I appreciate any suggestions.

IMG_20110703_114959.jpg


IMG_20110703_111252.jpg


IMG_20110703_111156.jpg
 
Register to hide this ad
The cheapest thing you could do, at least until your budget improves, would be to turn it (and its mate on the other channel) into "passive radiators". That way both channels sound the same.

If you do that watch for a significant change in impedance that may occur and, hence, screw with your amplifier.
 
try hooking it to your speaker wire by itself (volume at min. of course) and test it that way.
martin
 
Last edited:
Blast said:
The cheapest thing you could do, at least until your budget improves, would be to turn it (and its mate on the other channel) into "passive radiators". That way both channels sound the same.

If you do that watch for a significant change in impedance that may occur and, hence, screw with your amplifier.
Click to expand...

Hopefully my Kenwood Basic M2 could deal with the impedance challenge.

marloubow said:
try hooking it to your speaker wire by itself (volume at min. of course) and test it that way.
martin
Click to expand...

I think I'll try this, but I'm not expecting much. It really seems to be dead.
 
They may not relate to the problem you're experiencing but doesn't that model have those crappy circuit breakers on them? I had more trouble with those things not passing current and it would cause servere channel imbalance, loss of output (lower output but working), tweeter dropout, etc, etc. I just bypassed them versus keeping them in the look and it was like a veil was lifted off of these speakers....literally. EVERYTHING sounds better about them now.

Just a thought....might be something to check out as being a potential for the problem you're having. But as my buddy Dave from Speakerworks (in Tulsa) told me in an email the other day, "I give the same advice on circuit breakers as I do xxxx speakers. First, load them in the trash; second cover them with lighter fluid; third, strike match and roast marshmellows." I omitted the brand of speakers he hates with a passion but he would be glad to tell you what they are :D
 
I think that a pair of smaller Norman Labs, with the same woofers as yours, is in my local CL. Cannibalism is an ugly thing, but in this case, those 10s are superior. The asking price is $150, but they have been on CL for several months and the seller may take less.
 
Last edited:
I know the Model 7's on CL you're talking about. I actually have some model 7's already. They're taking the place of the 10's in my main system while I resolve this. The woofers in the 7's are 12"
so they won't work as a replacement.
 
undergroundr said:
I know the Model 7's on CL you're talking about. I actually have some model 7's already. They're taking the place of the 10's in my main system while I resolve this. The woofers in the 7's are 12"
so they won't work as a replacement.
Click to expand...

Gotcha - I don't know all of my Norman models.
 
tensleep said:
I think that a pair of smaller Norman Labs, with the same woofers as yours, is in my local CL. Cannibalism is an ugly thing, but in this case, those 10s are superior. The asking price is $150, but they have been on CL for several months and the seller may take less.
Click to expand...

$150 for 10's ?


Steve
 
I just passed on a pair of Model 7's fairly local that went from $150 down to $40 because he discovered, once he removed the grills finally, that one original woofer had been changed out to a Jensen car audio 12" sub. I could have gotten another woofer rebuilt from my buddy Dave in Tulsa but, by the time I did that, paid for shipping ,etc, I would have been at over $100 for a pair of them. After spending about that much on my pair of Model 9's last year, it just didn't make sense. Now, if both woofers would have been original. it would have been a no brainer.
 
The 9's might have been for that "era" but there was also the Model 12's that had (2) 10" woofers per channel in a separate cabinet and then each side had a slender vertical column with a pair of dome mids (I think?) and a Panasonic leaf tweeter. That same leaf tweeter was used in some of the last generation upper end models, too, IIRC. Seems like I have a picture of the Model 12's somewhere on my PC....I'll have to look. The Model 12's would have to be one of the more rare models.
 
Well, I spent some time with the driver today. Looks like the spider is broken in a few places. Should I be able to get continuity all the way to the voice coil wires as they're going onto the coil cylinder? I didn't have any luck.

Tried hooking the driver directly to an amp. No response.

I'm interested in the idea of disconnecting the upper 10 in the other one. At least I could get imaging back and I think it would still sound better than the Model 7's. But it looks like if I disconnect any of the terminals, I lose continuity to the lower woofer and it shuts off. Any idea how to do this easily?
 
Well, I see two ways to do it.

For either option you would leave both wires connected to ONE side of the woofer. So, in a sense, you will be using the woofer as a terminal strip for one set of wires. Then...

Option 1: Disconnect both wires from THE OTHER side of the woofer and move the "live" wire to connect the lower woofer back up. This probably gives you a leftover jumper wire for each cabinet. You'll want to keep said jumper for when you get the dead woofer repaired (and not lose them like I would).

Or, option 2: Disconnect both wires from THE OTHER side of the woofer and "simply" connect them together. I might tend to consider soldering the backs of the spade connectors together. Or soldering a short jumper wire to/between each of the connectors. Whatever I did would be in such a manner that the solder does not get near the connector itself.

Knowing nothing about Norman speakers, or the age of yours, I might also suggest, since you have them both open, you think about replacing the capacitors in the crossovers. You'll want advice from the Norman gurus on that, though.

Brian
 
Well, a solution fell in my lap this weekend. I picked up a quite nice pair of Model 8's for $25 off CL. They're beautiful, and I enjoyed listening to them for a couple hours. Strong bass and great vocal presence, although I was finding the gritty high edge of male vocals overprominent.

IMG_20110710_190724.jpg


Regardless, their beautiful original 10" butyl surround woofers were too much to resist. They look identical to the original Model 10 woofers from the front, but the magnet is different. The black one with the rectangular magnet on the right is the original model 10.

IMG_20110710_200309.jpg


Sounds perfect so far. Great to have the Tens back in action!

I had some JBC 320W automotive 10"'s ("Just Be Cool") that I put in the 8's for the time being and they still sound perfectly respectable to my ears. Maybe if the original 10" gets fixed the drivers can all go back to their proper homes.
 
New caps and tube power will tame the hell out of those tweeters. :music:
My 10's have the woofers like the round one on the left. I had to make the extra 4 holes.

Steve
 
You must log in or register to reply here.
Back
Top Bottom