loth-x grandeur stamm basspipe?

[ark]

http://www.lothx.com/GRANDEUR.htm

Has anyone any experience with these?
Just when I thought I'd seen it all... Has anyone an idea how the folding works? or diy examples?

If they came from anyone but stamm.. i might be highly sceptical, but to date I've loved ever model ive heard.

i have a pair of saba greencones i want to do something with, perhaps i could try to mock one of these up?

help!
: )

thank you!

[ark]

I'm really surprised at no responses to this?
of all the foldings i've played with (in cardboard) i'd never thought of this. anyone heard or tried something like this? is it a horn or a tline?

[mike.e]

Tline it seems. If the unit is 106db/1watt near ~30hz , then i cant beleive it- because a 30hz horn wont fit in that size box.

Probably Tline.Perhaps the frequency resposne limits stated are the -10db points


Tlines and horns are both 1/4wave devices

The first is a resonant pipe,the second a highly damped resonator with increased acoustic coupling also.

its usualy quite easy to pick out the basshorns-huge mouth and huge length!

Where as the Tlines are long and small area-and often have the Large area end near the driver.

Also Basshorns have a compression effect on the driver too


Cheers!

[ark]

thanks.
i'll start cutting the cardboard later this week and see what I can make out - who knows, i may stuble upon a wormhole portal

[AJ]

ark,

I saw the Grandeurs a month or so ago and was more interested in the reflector than the pipe/horn. Just to check it out, I slapped together this cute little guy using two Fostex FE164's per side:



I intially wired the two drivers parallel and just let them run free above 150hz. I was surprised to say the least at what I heard. Quite efficient and remarkably point-source - if you were to cover them with a grill, you'd never know they weren't direct radiators.

The obvious question is, "What about comb effects?" Well, they're there, but not as bad as I expected. I listened to them in that config for a coupla days before trying any changes and it wasn't at all painful. The imaging was insanely good and the sound was just plain huge. then I started making some changes...

First, I disconnected the top driver and this was when the combing became noticable - I had to hear it without combing to hear the combing effects. Most of the problems seem to be in the upper bass/lower mids, because it improved with only one driver. Two drivers were a bit muddy, but it's easy to overlook until you hear a single driver.

Next, I crossed the driver on bottom to the driver on top at about 4khz, basically turning the whole setup into a 3-way with the subs in the background. I'm using an Ashly electronic XO so it was easy to triamp the whole thing. The FE164 is pretty good out to 15khz so using the top driver as a "tweeter" worked out really well. In this configuration these things really sounded good - head shakingly good (as in hard to believe, given the odd setup). With the apex of the reflectors at ear height, it was seamless point-source with a verrrry wide sweet spot. Beaming restrictions were pretty much eliminated by the diffusion of the reflector. Very cool experiment and I'm going to rebuild another set with some driovers I actually like. FE164's aren't my cup of tea, but this would be a terrific way to use my FX200's.

So anyway, I know this doesn't help you with the pipe, but I can vouch for the viability of the reflector.

Allan

[ark]

WHoa! Allen, your the Bomb.
You answered a good part of my question.. i was really curious about the effect of the reflector on imaging.

and look at those monsters in the background? MOnsters!!

ha!

anyhow. I have don't have much to work with these days.
i scrapped evertything i owned in a recent move.
so i'm gonna start from scatch with a pair of 8" saba greencones, a 30 dollar class T digital amp and a walkman.



this weekend i'll try a strait open baffle with 31x36" rectangles of mdf and some perversion of the loth-x granderur.

i'm don't know what combing means though.
i'll have to look it up so i understand completely what you were talking about.

anyhow. i'm glad someone else has tried this reflector idea and had good results. i wonder how much of some of the old lowther boxes benfited from similar reflector functions.

[4real]

You might take a look here: http://gainclone.com/phpBB2/viewtopic.php?t=405

[ark]

thanks! you all are terrific.