Altec N-3000-E Mystery

[soundguy64]

Has anyone here had any experience with the Altec N-3000-E "dividing network" which comes with the 601-8D Duplex speaker?

I have recently had occasion to get inside of one. Since the Duplex speaker is actually a separate woofer and tweeter mounted coaxially, I had always assumed the N-3000-E was a two-way low-pass/high-pass filter network, crossing over at 3KHZ. Turns out, it's not. It's a 3KHZ high-pass filter with a 10db level control, all for the tweeter. The woofer is just wired straight through to the network input, basically connecting it directly to the amp. There is no low-pass filter to roll off the woofer's output above 3 KHZ. And this woofer has a significant output above 3KHZ.

I've got four of these speakers, and I'd always wondered why they sounded so mid-rangy. If any other 601-8D owners have wondered the same thing, now you know. That'll teach me not to read "crossover" when I see the words "dividing network". It's a fine print thing, I guess. Or maybe a reading comprehension thing. :banghead:

One other issue: If the wiring diagram shown on the network's casing is followed judiciously, the tweeter will be wired out of phase with the woofer. I'm not sure that's a good thing.

Btw, does anyone know a good place in Southern California where they can fix a blown 601-8D tweeter? I checked Speaker Repair Pros, but they don't show the tweeter in their repair list. (They can recone the woofer, but I didn't fry that part.)

Many thanx to all.

[Perplexed1ne]

Has anyone here had any experience with the Altec N-3000-E "dividing network" which comes with the 601-8D Duplex speaker?

I have recently had occasion to get inside of one. Since the Duplex speaker is actually a separate woofer and tweeter mounted coaxially, I had always assumed the N-3000-E was a two-way low-pass/high-pass filter network, crossing over at 3KHZ. Turns out, it's not. It's a 3KHZ high-pass filter with a 10db level control, all for the tweeter. The woofer is just wired straight through to the network input, basically connecting it directly to the amp. There is no low-pass filter to roll off the woofer's output above 3 KHZ. And this woofer has a significant output above 3KHZ.

I've got four of these speakers, and I'd always wondered why they sounded so mid-rangy. If any other 601-8D owners have wondered the same thing, now you know. That'll teach me not to read "crossover" when I see the words "dividing network". It's a fine print thing, I guess. Or maybe a reading comprehension thing. :banghead:

One other issue: If the wiring diagram shown on the network's casing is followed judiciously, the tweeter will be wired out of phase with the woofer. I'm not sure that's a good thing.

Btw, does anyone know a good place in Southern California where they can fix a blown 601-8D tweeter? I checked Speaker Repair Pros, but they don't show the tweeter in their repair list. (They can recone the woofer, but I didn't fry that part.)

Many thanx to all.


This driver appears to be a red headed step child. But, I am also tracking down information about this driver. My 601-8D pair look like they have never been mounted and the wires of the N3000E have never been stripped. What enclosure are you contemplating? And, have you had subsequent luck getting feedback on the phase issue?

Cheers!

[Riley Casey]

An old thread I know but I just got around to measuring my Altec 601Ds after twenty plus years having one mounted on the kitchen wall and the other on a high shelf in the corner of the basement. In answer to the question about the polarity of the tweeter you can see from the blue trace in the attached screenshot that the tweeter connected in the way indicated on the crossover yields a very good phase trace. The green trace is the same speaker with the tweeter level fully off. The red trace is the other speaker which had it's tweeter die an ignominious death years ago. Low end is much better in that one so I suppose I should look into that but these speakers are loaded into very small sealed boxes rather than the Altec specified designs like the 416s so don't draw any conclusions about what the low end would be properly loaded.