Question about 604 Duplex Horns

[RonSSS]

A good question for Todd White and folks:

Can the Mantaray horn from the 604-8H,8K be retrofitted into the earlier 604's?
I assume that since Iconic is making their own duplexes now that the horns might be available......

Ron

[joe3rp]

I am also interested in this Mod...A mantaray horn replacement on a 604H (originally with the 6 section horn).

[billfort]

Here's another guy that would love to know the answer to the above. Also, what is involved in removing and more importantly, re-installing the horn on a 604-8G? I want to consider making wood horns in various configurations to try out in mine but will can this idea if a horn change means a re-cone.

[zelgall]

Hi Bill. I can tell you how to get the horn off, but getting another back on is beyond my scope. The felt that surrounds the horn can be cut away with a razor/exacto. Slide the blade along the side of the horn carefully. The felt is flexible enough to pull it away slightly at which point shine a light into the gap and look for two small bolt heads, undo these and the horn is off. I have done this on my E's and G's, both came off without undo problems. Getting them back on is a b*tch without removing the felt completely.

[donaldpatten]

I have a 605A that had a UREI blue horn. GPA reconed it and replaced the horn with an OEM horn. The UREI horn was glued to a plastic throat mounted to the 605A. I recall Bill said he used a lot of solvent( acetone ?). Sounds like you could go the other way. Don

[rafaro]

Hi Guys just passing by:

The older 604s have a 1 1/2" exit into the horn where the newer ones have a 3/4" exit into the horn so the answer should be no dice to pull this switch. But there are commercially available 1 1/2" horns available (hint)

RAFARO

[selmerdave]

I may be wrong but I seem to recall that the horn mount is different so they are not compatible. Having said that, it would seem there would be a market for an improvement that would fit the C-G mount.

Dave

[jmarkwart]

Hi Y'all,

It may not be as easy as just replacing the external horn. The early 604s and 605s all have what appears to be a conical expansion from the exit of the phase plug to the mouth of the externally mounted exponential horn. By contrast, my 604-8Hs appear to have a waveguide with a contant square cross section from the phase plug to the horn mouth. (the other Mantaray duplexes probably do too) I suspect the early conical expansion would need to be replaced as well if the CD horn's benefits were to be realized.

Jeff