Altec 604-8G Diaphragms

[Nyjblbob]

Even though my 604G's have good Altec Aluminums, after they go for Re-cones, I will be getting 16 Ohm Radians. I can't hear over 12K anyway,
and when Biamping i like to play with different Xover points, and the radians have smoother/stronger mids.

 

[Doug Weiss]

Even though my 604G's have good Altec Aluminums, after they go for Re-cones, I will be getting 16 Ohm Radians. I can't hear over 12K anyway,
and when Biamping i like to play with different Xover points, and the radians have smoother/stronger mids.

Bobhorn, that's another helpful comment. I've been leaning toward Radian, but the "originality" factor keeps creeping back into the picture. Since you're running 8G but considering 16 ohm diaphragms, are you already biamping or did you modify your xover? BTW, I also have an SP3a1, Fairchild 255. Wish I had kept my Cit 1,2, and 3, but I traded them in a weak moment.

 

[Nyjblbob]

This pair of 604's I pu knowing they needed Re cones.So I haven't used them at all.
But 25 yrs ago I had similar ones one needing a diaphragm. I got the 16 Ohm Radians, and left the Stock 8 Ohm X-overs in them.
The difference was dramatic! I know the over points changed, but Unbelievable mids. yes at a slight decrease in Highs.
I wound up selling over 20 pair of Radian 16 Ohm
Diaphragms to Owners of 604's. No one Ever complained, and to my Knowledge went back to the altec's
I am now starting to play with a mint pair of 604E's I just PU from a fellow Ak'er on Bartertown.
While I like the Citations,and they are triode switchable, the Fairchilds, do everything better.
BTW for a real treat try biamping the 604's using a SET amp, 45's or 2a3's on the horns. they don't need any more than 1.5 watts!
my Citation 1 is my reference pre, but My Arc sp3a is more enjoyable. best tone controls on any Vintage preamp ever

 

[Mr. Bissness]

I just pulled a pair of radian 1228-16 symbiotic and replaced them with pair of GPA-16... these are installed on a pair or 808-8b with the loading caps removed and felt installed.
I can say the GPA produce a much higher frequency and sound closer to my original diaphragms loaded in a pair of 802d.
The next pair I purchase will be replacement GPAs

 

[Nyjblbob]

a great legacy video if you listen closely he mentions 604's

 

[edgewound]

Bobhorn, that's what I needed to hear. Didn't find that kind of animus toward them in a handful of google searches, but they were added to the available options at the 11th hour. Just trying to get it right the first time based on input from the experts.

You cant go wrong with the Radians.

Use the same impedance as your originals.

 

[edgewound]

I just pulled a pair of radian 1228-16 symbiotic and replaced them with pair of GPA-16... these are installed on a pair or 808-8b with the loading caps removed and felt installed.
I can say the GPA produce a much higher frequency and sound closer to my original diaphragms loaded in a pair of 802d.
The next pair I purchase will be replacement GPAs
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What you're hearing is distortion from the metal suspension resonance.

 

[Mr. Bissness]

So I need to clarify my statement above. I realized I was using one with a loading cap and one without. I prefer the radian after a second comparison. My wife, who is my goto A/B QC/QAer said, “Radian 1228-16 seems to be more cozy and better for the speaking voice. The GPA16 seems to be more room encompassing with a higher crisp sound. Both sound good for different parts of the song, Really just personal preference in my opinion” ... I completely agree. Good luck with your decision.