System setup with seperated bassmodule?

[e-side]

For my new system I'd like to use bass horns. To get them down to 60 Hz I'll stack 2 horns together. This results in a mouth size which is large enough for my design, but I don't have the space and money to build 4 horns (2 stacked per side for stereo).

Therefore I thought that maybe a seperated bassmodule could solve this problem; The 2 horns centered between the main speakers - right in front of the listening position. The main speakers will do everything above 300Hz (see attachment).

Could this be a successful alternative or will there be problems with mono/stereo imaging, time alignment etc.? Should I change the x-over-freq between the horns and the main speakers?

[Geoff H]

Hi e-side. I think the xo at 330 hz is to high. Our hearing is directional down to about 180 hz.

You may find that 2 separate horns will couple and reinforce the low fs. Dave will know more about that. Where are you mr frugelhorn?

Geoff.

[wigginjs]

I think this may be a debated topic, but I was looking up information on aural localization of low frequencies recently and everything I saw pointed to ~100Hz as the beginning of localization. My 2c

[Geoff H]

m0tion, your 2c may be worth more. For quite some time I believed in the 180hz figure, read it a number of times. However, I am fine tuning my system and crossing over at about 100hz seems to give better imaging. That could be due to less lower midrange from the common bass channel. It may have something to do with the particular mix of drivers. I don't know. But it sounds better, so it's staying that way.

It's a bit different to. Common Bass channel XO

Regards,
Geoff.

[e-side]

Originally posted by m0tion
I think this may be a debated topic, but I was looking up information on aural localization of low frequencies recently and everything I saw pointed to ~100Hz as the beginning of localization. My 2c

The main speakers will be closed boxes or OBs, which have a different 'sound' than horns. Could I get any problems with those mixed 'sound types'?
Because before you mentioned the localization problem I thought that it would be better to have the bass frequencies (up to about 300Hz) covered by one kind of enclosure, horns in this case.

In other words, could I get any problems with using both horns and OBs/Closed Boxes for the lower end?

[wigginjs]

I'm not really an expert in this area, so keep that in mind. My thinking on that subject would be that the only difference in "sound" between a horn, closed box, and OB for bass would be the following:

* Room interaction:
With horns and closed box you will have very noticeable "room modes" and they will significantly less noticeable with OB.

*Group Delay:
The audibility of group delay is very debatable, I think there is a thread going on about it right now. Group delay will be lowest with closed box (I believe) and highest with OB (I would imagine).

Horn and closed box should have pretty similar performance with the exception of the horn having higher sensitivity. I might be speaking out of turn here, someone should fact check this. Vented (bass reflex) enclosures would bring up some other differences, but you don't seem to be considering them. I think you'll be fine as long as you have able to perform some equalization to clean up the response curve.

Since you're placing the bass enclosure in the dead center of the two stereo speakers your localization won't be as screwed up as if you had the bass enclosure somewhere obscure (like behind your couch), but I still think it would be smart to let the main speakers go down to 100Hz or lower.

[Cal Weldon]

I agree with what the others have said.

Lower your XO point and have the mains carry more. Do you have mains yet? Are they capable of going down to 100?

[e-side]

Originally posted by m0tion

Since you're placing the bass enclosure in the dead center of the two stereo speakers your localization won't be as screwed up as if you had the bass enclosure somewhere obscure (like behind your couch), but I still think it would be smart to let the main speakers go down to 100Hz or lower.

That's useful to know, for OBs need a quite large baffle to get down to 100Hz or even lower when no equalization is used. This way size does become an issue, the horns have to be large already.

I don't have mains yet, I still have to build them. OB isn't an option anymore, so I think that I'll go for closed or TL.