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Radian 475-PB8 for temp replacement in Altec 19's?

tomlinmgt

tomlinmgt

Lunatic Member
One of the 802 drivers is cutting in and out in one of my 19's (I swapped drivers with speakers and the intermittent operation is following the driver) but I'd like to keep listening to them and was thinking of just yanking both 802's out and throwing these Radian 475's I have sitting around doing nothing in there. They're 8 ohm so it shouldn't be an issue, I figured. Is there any concern I may be overlooking? Only other thing I can think of is a sensitivity mismatch...but there's always the level pots to pull out some high end if necessary.

Thanks,
Michael
 
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What the hell are you waiting for? :D

Take the bad one out, hook-up the Radian, and do a side-by-side. If they're just sittin' unused, why not. It's a starting point.

Some pics would be nice also. :yes:

Have some Fun.
 
"knows enough to be dangerous". HaHaHa. Welcome to the club. :D Done some whoppers in my day. :scratch2:

I'm sure there's a lot of us out there, but are a bit "shy" to admit it. Testing things out comes with the territory. If you don't try, you'll never know.

Changing things like drivers, caps, stuffing, wire, ect. may work or not, but it gives you a baseline for what can be done. No shame in asking questions. For me, that's how I learn what and what not to screw up. :D

Keep us updated. This might be a "Holy $hit" moment.

Enjoy your New Year.
 
cablephil212 said:
"knows enough to be dangerous". HaHaHa. Welcome to the club. :D Done some whoppers in my day. :scratch2:

I'm sure there's a lot of us out there, but are a bit "shy" to admit it. Testing things out comes with the territory. If you don't try, you'll never know.

Changing things like drivers, caps, stuffing, wire, ect. may work or not, but it gives you a baseline for what can be done. No shame in asking questions. For me, that's how I learn what and what not to screw up. :D

Keep us updated. This might be a "Holy $hit" moment.

Enjoy your New Year.
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I hear ya. I consider myself quite fortunate to have performed a total recap of my QLS-1's and surgery on their sixteen EMIT tweeters without incident. That going as smoothly as it did will certainly be one of the mysteries of my own little universe. :D

I'll surely report back with my findings and likewise on the New Year.
 
Went ahead and swapped out the 802 for the Radian last night. Initial impressions are pretty favorable. There is greater clarity of content above 3kHz for sure, but it sounds like there's a tonality difference that makes the Radian a tad more lean. I only listened for a little less than an hour, so any judgement at this point would be premature. But as of right now it's sounding daaaaamn good. :yes:

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Pretty cool.

I found those horns really benefit from some Damplifier or other damping material on the outside surfaces.
 
Nice early 802G's.

Check the internal wire leads with regard to the cutting out issue. The issue is probably more relative to diaphragms that have already lived at least one full lifetime. Probably not exactly a fair shootout to compare them to moving assemblies decades newer.
 
bowtie427ss said:
Nice early 802G's.

Check the internal wire leads with regard to the cutting out issue. The issue is probably more relative to diaphragms that have already lived at least one full lifetime. Probably not exactly a fair shootout to compare them to moving assemblies decades newer.
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For sure, and with that taken into consideration I have A LOT of respect for the 802's. The working one still sounds excellent compared to the Radian.

So I guess the next logical step would be to send both up to GPA?
 
tomlinmgt said:
For sure, and with that taken into consideration I have A LOT of respect for the 802's. The working one still sounds excellent compared to the Radian.

So I guess the next logical step would be to send both up to GPA?
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I would inspect them myself first probably. If for no other reason, just to determine what's in them. Use a non-magnetic screwdriver, and be wary of anything magnetic getting "sucked" into the diaphragm where it can damage it.

Since these are early, they may have the 23744 "light" diaphragms. If it turns out that is the case, and one needs replacing, they are no longer made and the modern replacement may not sound exactly the same.

If a diaphragm replacement is necessary, because of their age i would consider replacing both at the same time.

If you go for replacing both, don't send your working phragm with your drivers if you send them in for inspection/re-charging, it won't come back.
 
I'm not surprised the 475s were pleasing, one of the finest horns I heard were early Unitys at Tom Danley's house when he was using the 475. As I recall he got away from the 475 in production use because it wasn't robust enough for his professional use but he liked the sound and the tested response very much.

The Radians are true "Southern California" drivers with a developmental link back to Emilar and Altec. They are grandchildren of Jim Lansing and John Hilliard, the Poseiden and Zeus of the Great Southern California Horn Gods.
 
tomlinmgt said:
Do you know what GPA is currently charging for an 802 rebuild?
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I do not know current prices.

If i had to guess, i'd say around 90 ea for the diaphragms. It used to be that if you shipped them the drivers, they would clean the gap, inspect the assembly, and re-charge the magnets at no extra charge. You'll probably need the wire kits too as the new phragms use a 1/4 inch push on terminal vs the old style spade, minimal charge for that.

Best bet, give them a call to confirm. Don't be bashful about including a note with your drivers detailing what you want done, perhaps referring to your phone convrsation.
 
Finally got around to cracking open the problematic 802. This glob of something in the middle of the wire lead sure doesn't look right. A prior repair, perhaps?

qy2ede8y.jpg


...with some black paper behind it to help it stand out a little better...

2ujesuze.jpg
 
Yes, that's a repaired diaphragm. I have to say, I love those Radians, one thing to try, reverse the polarity on the wiring to the Radian, based on your description of the sound compare it sounds out of phase to me, please update us!! :sigh:
 
dgwojo said:
Yes, that's a repaired diaphragm. I have to say, I love those Radians, one thing to try, reverse the polarity on the wiring to the Radian, based on your description of the sound compare it sounds out of phase to me, please update us!! :sigh:
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What on earth do you think would cause someone to have to perform a repair of that nature? It seems very strange to me that the wire lead would get damaged or severed in operation. :headscrat

And are you talking about the 802's sounding a bit more full than the Radians...that reversing the polarity on the Radians may remedy that?
 
tomlinmgt said:
What on earth do you think would cause someone to have to perform a repair of that nature? :headscrat


And are you talking about the 802's sounding a bit more full than the Radians...that reversing the polarity on the Radians may remedy that?
Click to expand...

The 23744 Lites are notorious for breaking the lead wires, the voice coil is still good and believe me, you'll go through heroics to save a 23744, I've repaired many but mine look different when repaired. :D

Yes, try polarity reversal, you might like it!! :music:
 
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