Stumbled on these Altecs at the thrift

[Rmac587]

Altec 601c "Duplex" in factory cabinets. Got some info from Mech986 and some off Internet.

Almost left them but then noticed Altec badge on back of one of them with L-Pad knob. Cabs were beat, but can look good with TLC. Grills are fixed in place. I opened the back and the cabinet (25"h 14"w x 12"d) had a space for a second driver that is covered up, a' la JBL L88 "plus."

Kind of weird, but they ran a second pair of raw speaker wires straight off the driver (you can see them barely on bottom right of driver) and out of the bottom of the speaker, while the actual old screw connects are on the back center.

I'm not sure if they were using these in lieu of the brown and white jack wires that are indicated on the crossover cover, or if they were somehow bi-wiring it. I didn't think to look when I took the back off, and I can't tell if the original wires coming off the screw jacks pulled off or were disconnected.

Haven't tested then yet. Pretty intrigued. Very efficient rating, 99, meant for low power tubes. Anybody have these or their big brothers?

 

[Rmac587]

I'm a bit torn between wanting to keep them in case I buy a low power tube amp or selling them to finance A low power to amp and using my Crites modded Klipsch Forte I in that role.

I'm about to acquire some JBL-I've wanted some for a long time, to use with my Sansui AU-717, rebuilt courtesy of CDFixer.

My goal was to have only two sets of speakers and two amps.This complicates the equation. Also, does anybody know if I can use the same driver and crossover network in a different configuration?

 

[Rmac587]

Better pic of driver with improvised wires added.

 

[Blue Shadow]

Those are well bought. Hope they are fully functional.

 

[Rmac587]

Me too Blue. I found a good AK thread on them. The tweeters are delicate and hard to replace.

Those are well bought. Hope they are fully functional.

 

[Xtinc]

Nice thrift find. Not sure what's going on with the wiring, but a few scenarios possible.
1. Tweeters stopped working, bypassed crossver and ran woofer independent.
2. Crossover stopped working and bypassed crossover just to run woofers.
3. Crazy attempt to bi-wire / amp while leaving original wires attached from crossover.

Either way you should test both HF and LF drivers. If they read good, remove the extra wires and test.
Working 601c drivers are worth some decent $.

 

[elitopus]

If the 3000 series tweeters don't work at least you have a nice pair of 414a drivers. I love my 414's.
I run mine in some small boxes around the same size as yours. I use a small horn with Renkus HF drivers and a first order xover on the horn.

Nice find!

 

[Rmac587]

Nice thrift find. Not sure what's going on with the wiring, but a few scenarios possible.
1. Tweeters stopped working, bypassed crossver and ran woofer independent.
2. Crossover stopped working and bypassed crossover just to run woofers.
3. Crazy attempt to bi-wire / amp while leaving original wires attached from crossover.

Either way you should test both HF and LF drivers. If they read good, remove the extra wires and test.
Working 601c drivers are worth some decent $.

Thanks Xtinc! Will pull them tomorrow and test!

 

[sann]

Nice find, and a fantastic driver if the HF is working, and even if it is not, as elitopus said, you have got a 414 which is considered one of the best driver for midrange ever made, you could pair it with Altec 806 with 32b horn like JELabs and have a great system running.
But lets first hope that the HF is working.
-sann

 

[Rmac587]

If the 3000 series tweeters don't work at least you have a nice pair of 414a drivers. I love my 414's.
I run mine in some small boxes around the same size as yours. I use a small horn with Renkus HF drivers and a first order xover on the horn.

Nice find!

Fingers crossed Elitopus!

 

[Sam Cogley]

If the 3000s are working, be kind to them. They don't want to see more than about 25 watts. They sound like angels singing when they're working, though.

 

[bowtie427ss]

Very efficient rating, 99,

You'll find that sensitivity number more than a bit optimistic. The reality is closer to 93db, much closer.

 

[kirk57]

I'm no Altec expert but aren't these cabinets kinda small for that driver?

 

[bowtie427ss]

I'm no Altec expert but aren't these cabinets kinda small for that driver?

Probably a little smaller than optimal. But, with a duplex, too small is far preferred over too large.

A small box still gives you all the middle magic, and that's what duplexes are all about. Too large a box does wanky things to the upper response of the woofer.

 

[tomlinmgt]

Probably a little smaller than optimal. But, with a duplex, too small is far preferred over too large.

A small box still gives you all the middle magic, and that's what duplexes are all about. Too large a box does wanky things to the upper response of the woofer.

This is interesting information to me. I have 604-8g's and have yet to put them into service for a variety of reasons, the main one being that I've read a minimum 26" baffle width is suggested (for optimal mid-bass reproduction) and I can't accommodate a cabinet that wide in the current location I have to locate the speakers. So, I assume you're talking about volume when you speak of enclosure size and that the 26" minimum width should be maintained? For instance, I had initially considered the Stonehenge cabinet for its smaller width dimension, but quickly lost interest after repeatedly reading it lost some mid-bass energy compared to something like the 620 cabinet. Just making sure I'm not missing or overlooking something.

 

[bowtie427ss]

The wide baffle supports lower than midbass. The OP is dealing with a smaller duplex that has different considerations than a 604. It's a 12 inch LF section that can play well a full octave above the LF section of the 604. Then there is the minimum 3khz XO point of the HF section to consider, it cannot go any lower. The LF section of his 601 duplex is capable of playing as low as the 414 woofer. But, to get it there the necessary tuning/alignment would prempt any kind of smooth response as high as it needs to go to meet it's 3khz minimum tweeter. In his case, a box too small is preferable to one that's too large.

The 604 is a different animal, it's LF section has a much more powerful motor, and it's parameters need a large volume box and wide baffle to make smooth LF extension happen. The 604's HF section offers power handling that allows a much lower XO point so that the LF section isn't required to reach as high. Early 604's crossed at 1khz.

 

[tomlinmgt]

^^^
Thanks for all the great info...though had I paid closer attention I would've realized the OP's driver is a 601 rather than a 604 and wouldn't have imposed on your time to explain to me.
Still learned something (and hopefully some useful info there for others), so not a total fail.
I had actually considered one of Great Plains 12" Duplex drivers because of my space limitation situation, but decided to try Klipsch Chorus II's instead and shelf the 604's for a future opportunity. Seein as the OP has Crites modded Fortes (I've done the Ti tweeter swap and also have the Crites xovers but haven't yet installed), I'm curious to see how this develops.

 

[Rmac587]

I'm no Altec expert but aren't these cabinets kinda small for that driver?

That's what I was thinking Kirk. I looked at pics of other cabs for that driver and they seemed larger. But Tom laid it out nicely, and something about them seems to indicate that they were matched, however imprecise that is.

 

[Rmac587]

So, if they test ok on the DMM, is it safe to test them on low volume with my sansui, 85wpc?

 

[Rmac587]

^^^
Thanks for all the great info...though had I paid closer attention I would've realized the OP's driver is a 601 rather than a 604 and wouldn't have imposed on your time to explain to me.
Still learned something (and hopefully some useful info there for others), so not a total fail.
I had actually considered one of Great Plains 12" Duplex drivers because of my space limitation situation, but decided to try Klipsch Chorus II's instead and shelf the 604's for a future opportunity. Seein as the OP has Crites modded Fortes (I've done the Ti tweeter swap and also have the Crites xovers but haven't yet installed), I'm curious to see how this develops.

Will keep you advised Tomlin. I installed the titanium diaphragms and recapped them before I realized the original owner had substituted in a forte II crossover on one of them. I recently ordered brand-new crossovers from Bob because I got tired of waiting for a Forte I crossover the pop up on that website. Trying to find time to do the new crossover install and also new mid-range diaphragms. The titanium diaphragm did wonders.