2312 options

[bldozier]

Hi I'm new to the fourm, but anticipate all the comradery, an knowledge from its members.
The project I have is a 4333 a/b project, I've attain a sole cabi et and im swiftly closing on a 4331 thanks to a member in upstate Ny.

The 2312 horns are used here, though I have note seen a pair for sale or trade in quite some time as I have been toying with this project for about 1 year.
can anyone explaine the sonic difference in h92 horns and the h91s and why I need to use the h92 2312 with the project.
Also do I have a alternate brand. ive seen wood, ive seen shiny painted metal stuff, but nothing in concrete, concerning a replacement.

[speakerdave]

Hi I'm new to the fourm, but anticipate all the comradery, an knowledge from its members.
The project I have is a 4333 a/b project, I've attain a sole cabi et and im swiftly closing on a 4331 thanks to a member in upstate Ny.

The 2312 horns are used here, though I have note seen a pair for sale or trade in quite some time as I have been toying with this project for about 1 year.
can anyone explaine the sonic difference in h92 horns and the h91s and why I need to use the h92 2312 with the project.
Also do I have a alternate brand. ive seen wood, ive seen shiny painted metal stuff, but nothing in concrete, concerning a replacement.

You need the H92/2312 horn for the 800Hz crossover frequency, which is too low for the H91.

[bldozier]

Thanks sd
so what type of sound is made at 800Hz is the cabinet tuned to this frequency?
If I were to have to network rebuilt for h91 horns for instance what frequency is this? Will the cabinet still perform good.
whats the sonic difference from the h91 to the h92 and can the average joe hear it.

[speakerdave]

Thanks sd
so what type of sound is made at 800Hz is the cabinet tuned to this frequency?
If I were to have to network rebuilt for h91 horns for instance what frequency is this? Will the cabinet still perform good.
whats the sonic difference from the h91 to the h92 and can the average joe hear it.

Your questions would suggest that a lot of this is new to you, so you are wise to be replicating an existing (already engineered) speaker system rather than designing from scratch. A replication should be done exactly because departures take you into designing from scratch.

That having been said, I understand that having found a second cabinet you are ready to move ahead. You might consider keeping an eye out for some H92's and at the same time rigging up a temporary substitute that would be a ballpark match for the frequency response and throw pattern of the H92 with dispersion lens. If it were me I'd try a pair of JBL 2345's. It is an 800hz horn of heavy cast aluminum with aquaplas damping. I would not modify the cabinets but would mount the 2345's to a small baffle and sled to set on top if the cabinet. Bolting to a baffle would further dampen the horn and would also help with loading below crossover.

Since you are buying something from subwoof already (he's a sound guy) you might ask him if he has a pair of 2345's sitting around. I could sell you a pair, but shipping them across the country would be expensive.

Understand, crossovers are developed for specific horn and driver combinations in a certain baffle, so my suggestion would not be a perfect match. I think it would be close enough for city folks temporarily.

[subwoof]

The first gen "studio monitors" used the 4502 cabinet, the 3110 ( 800hz ) crossover and the 2307/2308 horn lens with the venerable 2420 driver. The original woofer wwas a variant of the theater 15 - the 2216B but of course other woofers were used on special order and studios didn't need much power back then

It was found that the horn was too short to work properly in the crossover region and the stock utility network also needed to be refined so the 43XX series came out in late '74 using the same cabinets ( for a short time ) and some new ones to create the new 4 way models. The 15" woofer was replaced by the new design foam surround 2230 ( then the 2231 ) and finally the 2235H when alnico became scarce in late 78.

The longer horn is definitely required ( and yes I have some ) along with the lens ( often missing and/or broken ) for the best performance. As dave said, the original radial horn ( 2345 ) on top with matching cabinets does sound nice and in fact was sold as a small theater system way way back when.

On the 1" driver I would suggest the 2425H ( or 2426H ) with the dia's aquaplas coated - this would be the lowest distortion and longest lasting option possible since the old 2420 dia's are unobtanium and very very rarely found in usable condition due to fatigue. Same for the newer version ( the 2421A )

All in all a worthwhile project but try to stick close to the original design as much as possible. Reinventing the wheel is not easy or cheap..

sub

[bldozier]

Alas the finer print...
I will continue to read, mike.

Before im asked to walk the plank.

[mech986]

Yep, much easier to get the H92/2312 horns which work best in this cabinet and system with the 3133 crossover. Any of the above compression drivers that were mentioned would be a suitable option for the midrange. Otherwise, you would have to consider an outboard midhorn as mentioned.

Subwoof, can you get the diaphragms aquaplased? I'm thinking of doing this again and 4313B had done a pair of LE85 titanium diaphragms for me a long time ago, haven't asked him if he can still do this on request.