Altec Lansing

[GM]

Originally Posted by grandville45

Also How High should I go on the top plate above the bass horn when i flip these around?

25" according to the A800 literature.

GM

[grandville45]

Originally Posted by GM

If a 511 horn, then dense open cell foam can be used to make a spacer. The 811 would need to be mounted on the baffle and digital time delay used to align it.

High up is better when tuned high (big vent), but smaller vents are better mounted close to the floor.

Original mounting hardware is fine and you can mount it to a sled to help brace the bass horn's mouth and provide more mounting hole location options.

GM

GM Thanks!... I measured my old holes when i took out the horn last night center line of hole was 4 3/16 in the front ,can't remember the back ones by driver now, I will just do as u said and measure back 19.3 and use that as a guide then go from there. So just drill new holes right in the top of the bass horn and use t-nuts? I also do not have access to any electronic type devices so can't use a delay etc to set these up. When u say wire out of phase Do I keep it that way also? Above u said to wire it out then mount horn and switch leads just wondering? When U mean sled what exactly u talking about? I was going to mount the wings to the cab using a 2x4 gasketed to the side and attached to wing brace and then drill a hole thru it and use some ready rod on top and bottom going to each wing to hold it to cab, that way their removable and would be very secure also.The horn deal maybe I will have to build a double wall up there to mount to the front baffle board to keep everything in alignment? One other thing my vent was 18.25x 2.5 what will its size need to be now when it is 28.5 wide to keep it tuned where I had it?

[dominique-tanguy]

Originally Posted by Pano

And just FYI, the 1505 horn goes about 9" back on the Hiraga rig.

Hi Pano,

Do you mean 9 inches netween the front of the 825 and the front bracket supporting the 1505B?

[grandville45]

Ok here is a pic of how far back the horn will be with the proper 19.3 spec seems awful far back from the front of cab doesn't? It is 7" to front of cab from edge of block. FWIW it wasn't aligned when it was inside cab like you thought GM!... I think I will just build side wings otherwise I don't know how to make that horn mount work and sound right and keep the VC aligned

[GM]

That's just a starting point for finding the correct setback and since it's an 811, I imagine it will move forward somewhat, but not having timed one I don't know how much.

Anyway, as I noted, the easy way is to mount it to the top 'wings' and use digital time delay (TD). If you don't want to go this route, then from a sound quality (SQ) point-of-view (POV), better overall IME to properly align the horn and skip the top 'wings' since you're already getting good room loading down low.

That said, Altec would sometimes use a cab width horn baffle, so that's one option and I see no reason why the full size top 'wings' can't be used complete with connecting shelves if you want to go to the extra effort, though even if it's just a horn perched on top, any horizontal surface in front of the horn ideally needs damping to attenuate early HF reflections.

Long term though, switching to a 511 or some other much longer horn seems a good plan for full 'wings'.

GM

[grandville45]

Yea It Looks like when they were mounted inside it was about 16.25 or so to VC, maybe i will just go and match that on top and call it good? Here's is a pic of my new bottom baffle plate and port. The port is 10x 2.28,will test it tomorrow for loudness as its getting late and kids are trying to sleep,lol.. but it sounds pretty damn good on the bottom end! Had A friend of mine use bass box pro 6.0 to get me the port size by seeing how the curve looked using the woofer in a 11.47 cab, Figured a little bigger with horn out of cab now, and it looks pretty damn sweet!.. I will see if i can get him to send me that curve.

[GM]

23744 diaphragm receipt that won't display properly on this Altec Forum response: Difference Between 806 and 802 Drivers - Hostboard

GM

[GM]

Originally Posted by grandville45

.......maybe i will just go and match that on top and call it good? Here's is a pic of my new bottom baffle plate and port.

Yeah, if you're not going to do acoustic measurements, then stick with the 4-3/16" stock mounting setback.

I thought we 'agreed' to put the vent down at the bottom to at least get the max available vent efficiency/floor boundary gain. Hmm, I see casters though, so probably doesn't matter.

Looks like a ~32 Hz tuning..........

GM

[Pano]

Originally Posted by dominique-tanguy

Do you mean 9 inches netween the front of the 825 and the front bracket supporting the 1505B?

En effet, oui. But that was with the Westex driver and Hiraga's crossover. But I find that works pretty well for me with the 288 driver and the 1005 horn. It's a phase alignment thing.

So the mounting tabs are about 9" or 22cm from the front of the cabinet. This should be adjusted to your horns and your crossover.

[grandville45]

Originally Posted by GM

Yeah, if you're not going to do acoustic measurements, then stick with the 4-3/16" stock mounting setback.

I thought we 'agreed' to put the vent down at the bottom to at least get the max available vent efficiency/floor boundary gain. Hmm, I see casters though, so probably doesn't matter.

Looks like a ~32 Hz tuning..........

GM

Yea We did on the vent, but i cut these at work and I have a 2x2 at the very bottom to help with bracing that part of the cab, and i have heard to always keep a vent away from any blocks bracing etc. I will see how it sounds not like i can't make a new one .Yea if i had the tools to do it I sure would. How much is the stuff your talking about to get the proper phasing?. Here is the curve