Proud new owner of Altec Duplex speakers 604s and 605s

300man

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I have been aware and looking for Altec 604 and 605 speakers for several years. Finally I was offered and purchased one pair of 604 - 8G with Stonehenge III crossovers and one pair of 605B with N-1600B crossovers.

I want to either purchase some Altec cabinets or build my own for one pair of speakers and crossovers.

I've looked these over and preliminary testing indicates that these speakers and crossovers are fully functional and in good condition.

Let's say i am only interested in using one pair of speakers. Which speakers and crossovers do I put into service?
 
Thanks for the link GD, nice read.

Yeah it took quite a while for this speaker deal to come together but I am thrilled to have them!
 
604-8G's with Markwart phase corrected crossovers, and don't look back.

This guy knows a thing or two about Altecs so I'd follow his advice! :)

Congrats on the acquisition by the way! Very nice pick-up indeed. I have a pair of Model 18s with the 604-8K in them and even though the cones are not original and the crossovers are unrestored, they sound great. You have the makings of an excellent project there.
 
604-8G's with Markwart phase corrected crossovers, and don't look back.

+1

Keep the 604's.

I run 604G's, in 620 cabs, with the Markwart xovers. They sound great. And the xovers are easy to build.

And nice score getting the 604's and 605's. How did you end up with both pairs?
 
It was a package deal from someone that I knew and trusted. I had know idea he was into hi end audio. He was my last manager at work before I retired. I was filling my final separation papers in his office and he asked me what I was going to do with all my free time. I mentioned That I had several hobbies which included collecting vintage audio components. I then mentioned Altec and he raised an eyebrow. Then tells me he had some 604s and 605s. They were buried away in storage for years and they would be mine when he had the time to dig them out. I waited silently for a year and a half and then I got a call through a second party that he wanted me to call him. I knew why...Audiokarma...
 
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Good for you! I have a set of 604E's in Altec 612 cabinets and love them. The cabs are a little too small for best bass but a sub fills out the low end nicely.

I also just retired and one of my new passions is woodworking. The plane in your sig photo makes me think it's one of your pursuits as well. You could build cabinets for your 604-8G's. Look at designs based on the Altec 620 cabinet.
 
604-8G's with Markwart phase corrected crossovers, and don't look back.
So I looked int the Markwart XOs and i see the phase corrected, but only for the 604 - 8H not the 604 - 8Gs that I have?

Seems the simple MW xo has a note 6 that has different values of components for the Gs but the phase corrected does not.

Can anyone clarify this and break it down for me?
 
So I looked int the Markwart XOs and i see the phase corrected, but only for the 604 - 8H not the 604 - 8Gs that I have?

Seems the simple MW xo has a note 6 that has different values of components for the Gs but the phase corrected does not.

Can anyone clarify this and break it down for me?

The simplified 604G xover is still phase corrected. If you email Jeff, he can answer any other questions you might have about the build.

I emailed him about using resistors instead of the Lpad. He helped me pick the values.
 
The simplified 604G xover is still phase corrected. If you email Jeff, he can answer any other questions you might have about the build.

I emailed him about using resistors instead of the Lpad. He helped me pick the values.

Ok thank you for the clarification! I may contact him. Have to look into getting the pieces together for the simplified xo.
 
Ok thank you for the clarification! I may contact him. Have to look into getting the pieces together for the simplified xo.

Those are the ones I built. I really like them.

I used motor run caps, Jantzen coils, and Dayton resistors. Spent less than 200$ on the pair.

Oh and also Russian K75-12 bypass caps.
 
Well...it's been a while since checking in here. Time has a way of slipping away. I have not done the build yet and was seriously considering selling off the speakers...BUT if I were to sell them I first needed to test them. So as a quick and dirty test I hooked up the 604-8Gs and Stonehenge III xo to my stereo. I just wired them up and placed them on a area rug in my living room. This happened about a hour ago and I'm listening to them as I type this...Best of Sade is playing. Boy I can see the potential of these speakers and now I'm pretty sure I can't sell them!
 
Find yourself a couple heavy duty cardboard boxes, mount them in the cardboard temporarily. This will take them up a full level from just laying on the floor. Just getting them in a few square feet of baffle will smooth them out and bring the bass to life. Do this, and i'm pretty sure you'll put selling them on a distant back burner.
 
The 604 is more efficient than the 605 and will handle 2 times the power . If you want a warmer more distorted sound go with the 605 with the Alnico magnets. In any event the crossovers should be up dated. Even though some people will scream I would use the 1201 crossover with the two band adjustments if you can't find an original . If you can find the road map for a Urei 811 crossover it will allow your 604 to reproduce square waves accurately being time aligned if you are interested. I have no clue about Markwart. The The *H network has more advanced features than the G with special HF shaping, but will not allow time align ment. I would call Great Plains Audio for the best recommendations. They are making an advanced version of the H model with a horn similar to what Urei 604 used with an advanced crossover. They were also making an Advanced version of the 604 with Alnico magnets and the original multicell horn but with a more advanced crossover and diaphragm.
 
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Find yourself a couple heavy duty cardboard boxes, mount them in the cardboard temporarily. This will take them up a full level from just laying on the floor. Just getting them in a few square feet of baffle will smooth them out and bring the bass to life. Do this, and i'm pretty sure you'll put selling them on a distant back burner.

This. If you have a John Deere or other tractor dealer near you, their parts are delivered in very, very heavy cardboard boxes in large sizes, free for the taking.

GeeDeeEmm
 
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