Do Altec 604 hold up with modern music?

Joined 2004
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FWIW, here is a picture of a monstrosity I built a few years bad with a 604. They were the BUS - Big Ugly Speaker. The box was about 17 cubic feet, or around 480 liters which was what the T/S calcs called for, or maybe a little bigger. I used them both sealed and vented.

They started off with just the 604s which had been overhauled and renewed at GPA. The woofers by measurement were basically 515s, thus being very efficient and dynamic, quite amazingly dynamic. Only played down to about 48Hz tho, then rolled off. I didn't mind, as they were very solid down to that point, unlike many so called "20-20K" speakers.

Later, as seen below, I started experimenting with midrange horns, using the 604 as woofer and tweeter which worked well. I prefer the big horn midrange, but a lot of people prefer the punctuality of the coax.


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Nothing performs very well with denser, over compressed more modern music. OK, maybe the speaker on your phone. :p

IME, the 604 and 605 retain all of their advantages on more recent music. If you like thumping bass, you can add a peaky subwoofer and have a lot of fun. But maybe other people will have more experience. Mine is more with larger horn systems, tho I do really like the Altec coax drivers.

I am using a 605B in a 620 enclose (active crossover) and driving the bass with a Class-D Amp. Never had a better bass....

That's a great idea but it can be difficult to judge from one implementation. A bad crossover, a bad room or a bad box might lead to sub-par listening.

On the other hand, if you hear a really killer rig, you'll have the challenge of getting it to sound that good at your house. :p Best of luck finding a system to listen to. It's the smart thing to do. :up:

Ideally I’d fly out to GPA directly and demo them there. :D
fwiw my old Karlson K15 w. 604B reconed as "E" is the best I've heard so far with Gary Karr's bowed bass on "The Spirit of Koussevitzky"

I tend to dislike the sound of round wound strings "slapped" on electric bass (think "Seinfeld" interludes) - but love bass viola properly slapped (especially with gut strings)

Rap and hiphop bass drops at robust levels imo are too much to ask of a 604.(maybe a ferrite version -?)
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I had a 604C in a Karlson and used a Urie 801C which is an E-145 with a concentric 2425 as my center channel for years. Really enjoyed both. I would be very careful with the older alnico drivers my cones were paper with doped edges and light not exactly deep bass material. There is quite a bit of sub 40hz bass at high levels in modern music even if they can do well I would use a subwoofer just to protect the 604. Eventually that paper is going to start cracking and the more you can limit excursion the longer they will last.

Rob :)
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Joined 2004
Paid Member
I think the real question is does modern what goes for music hold up to the resolution the Altec Duplexes deliver?
I would say "No". :D So many recent releases are compressed to death with tiny dynamic range and a non stop wall of sound. Even the more sparse arrangements suffer from tiny dynamics, even if there is some breathing room in the music. Add a heavy dose of Autotune phase effect on top and what do you have? A mess. But it will at least be audible played out of your smart phone speaker sitting on the table a few feet away.

Although I think "Modern Music" mostly means extra bass heavy mixes. Those are a lot of fun, but they are just effects imitating a PA system with massive, multiple, high powered subs. Made famous by Reggae, but now used worldwide. If that's the effect you want to achieve, it has to be done the same way with big, powerful subs and plenty of them. Scaled to your room, of course! They should be EQed to fit the effect, just as they are in big PA systems. Horses for courses, as they say.