604 Conundrum

**Steve Schell** · June 25th, 2011, 02:52 AM

More 604 mania happening currently on this thread:

Lansing Heritage Forums

**Altec Best** · June 25th, 2011, 05:39 AM

Yes Steve these are Terry's that he posted here back in Feb. Very Cool to see something that early from Altec ! Great History ! Want to Thank Terry for sharing them with us.

http://www.hostboard.com/forums/f700...ell-these.html

**RonSSS** · June 25th, 2011, 01:53 PM

Sounds like you prefer the 604B. I would search for a mate to that and sell the orig 20ohm 604. It looks to be mint and will fetch a lot of money. More than enough to pay for another 604B with cash left over to maybe rebuild the crossovers.

Hope those X-overs aren't tar filled!

Ron

**TerryE** · June 25th, 2011, 04:16 PM

Originally Posted by Steve Schell

The first Duplex, the 601 field coil unit, had a 12 ohm, 1200 cycle crossover. The very first 604 units also had a 1200 cycle crossover, but were changed very soon to the 2000 cycle.

Steve, someone has questioned the authenticity of the N-1200-E crossover that comes with my 604 in a 605 cabinet that I currently have for sale on an auction site. I believe the crossover is original to the unit, but I don't know for sure. Is it possible that a very early 604 came with a N-1200-E crossover?

Thanks for you help.

Terry

**Steve Schell** · June 26th, 2011, 01:22 AM

Terry I would say that it is almost certain that the N-1200-E dividing network is original to your loudspeaker. Here's my logic... the field coil Duplex model 601, built immediately before your early 604, used an N-1200-C network, as listed here in the 1943 Altec Lansing catalog:

http://www.lansingheritage.org/image...943/page04.jpg

Note that the page was rubber stamped "Cancelled- see insert." This was because the 601 had just been discontinued and replaced by the 604. We are now probably in 1944, and Altec had not yet revised their catalog, but they had produced their first single sheet, two sided flyer on the new 604 as a "stuffer" for their still-in-use 1943 catalog. The two sides of this flyer appear right after the 601 page here:

1943

The first side of the flyer begins with "First Time In History." On the second side, note that it says "Dividing Network Crossover 1200 cycles." The only example of this catalog is the poor photocopy which I scanned for the Lansing Heritage site, so I am not sure whether the flyer was in color. Within a short time Altec would produce a fancy twelve page color catalog for the 604, also beginning with "First Time In History." In this catalog the crossover frequency is described as 2000 cycles, and the network pictured is the N-2000-B.

Now I'm not sure why the designation for this 1200 cycle crossover jumped from C to E, but the look, styling, configuration etc. is right for the period, matching the looks of the N-2000-B. From all the available evidence (including your apparently unmolested loudspeaker) it appears that the 604 was introduced with the N-1200-E network and changed very shortly after to the N-2000-B.

You can use my words in any way you see fit. I am one of the three co-founders of the Lansing Heritage web site, which along with 25c might buy a cup of coffee!

**TerryE** · June 26th, 2011, 09:31 AM

Thanks Steve. I can't seem to revise my ad today to add your comments- maybe Ebay blocks revisions within 24 hours of the end of the sale. Anyway, thanks for your help. I'll be sure to make a donation to the site when the auction closes.

**Lofiluther** · August 20th, 2011, 06:37 PM

It's taken me forever to get the time, but I finally ventured into those 9 cubic foot baltic birch cabinets today and extracted the 16-ohm 604B. They really are fairly amazing, and it's tempting to just keep the mismatched set I have, but ultimately, I would like to get a usable, reliable situation for my studio to augment my monitoring setup. My ultimate goal is to use them to mix, engineer and produce music -- something I've been doing for the past 10 years. I think I may be on the road to selling both the 20-ohm 604 and the 16-ohm 604B.

Trying to get this link to picasa working. . .

https://picasaweb.google.com/1091859...8/August202011

**Altec Best** · August 20th, 2011, 07:11 PM

Originally Posted by Lofiluther

Trying to get this link to picasa working. . .

https://picasaweb.google.com/1091859...8/August202011

Link works fine for me.

**Todd W. White** · August 20th, 2011, 09:47 PM

Just posted on the Lansing Heritage site about the 604.

Preparing to get flame broiled for it.

**cradeldorf** · August 20th, 2011, 10:42 PM

Yep Link works good for me too, what a beautiful sight. I know your feeling about a mismatched set but I don't think I could ever part with something like those. I would do what I could to get them to sound as close as they could and just enjoy them.