Sensitive Wide Range Open Baffles

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Jump to Latest
Magnetar

Magnetar

Banned
Joined 2004
SunRa said:
Hello Magnetar,

did you had the chance to read my post about compression chambers? (post 140 in this thread). I find your opinions and experience very helpfull. The question is if you find quality differences between cone loaded horns with or without compression chambers...

Thanks!
Click to expand...

In bass /low mid horns you can use the back chamber like a spring to annul reactants of the cone/motor/air. With a bass horn it's very advisable to do this. It will widen the bandwith in both directions and lower low frequency distortion. In a mid horn it can do the same but at the expense of the *possibility* of reflections in the chamber messing with the sound. In most cases I leave the back open if I'm expecting good response beyond 1K
 
S

SunRa

Member
Joined 2004
Hello Magnetar,

thanks for the response. I was actually refering to front compression chambers as you mentioned you are using for your midrange driver. My concerns about reflections, non-linear behaviour and diffractions of the wavefront where regarding the front chamber, as it is used by you and Avantgarde acoustics for example.

My link in post 140 was to BD-design. The Oris spherical horns are having a throat area equal to the Sd of the cone driver. This implies no front chamber. The same (I think) for Azurahorn manufacturer with it's Le'Cleach profile.

Do you have any informations about predicting the volume, shape of a compression chamber. I think this is more critical than rear chamber design.

Thanks!
 
Magnetar

Magnetar

Banned
Joined 2004
SunRa said:
Hello Magnetar,

thanks for the response. I was actually refering to front compression chambers as you mentioned you are using for your midrange driver. My concerns about reflections, non-linear behaviour and diffractions of the wavefront where regarding the front chamber, as it is used by you and Avantgarde acoustics for example.

My link in post 140 was to BD-design. The Oris spherical horns are having a throat area equal to the Sd of the cone driver. This implies no front chamber. The same (I think) for Azurahorn manufacturer with it's Le'Cleach profile.

Do you have any informations about predicting the volume, shape of a compression chamber. I think this is more critical than rear chamber design.

Thanks!
Click to expand...


http://mywebsite.bigpond.com/dmcbean/

It's all there front, back chambers, flares, throat size ......
 
S

SamL

Member
Joined 2004
Magnetar said:


I never measured the TS of the warriors just the voltage sensitivity and response. They re around92 db with 2.83 volts 50 to 800 cycles each. Wire in parallel and the sensitivity and power hancling goes through the roof.

- One woofer would be very poor

What needs to be considered is the sensitivity and xmax mounted on a board in 1/2 space at 50 cycles. When you do that you will see why a pair of 15's really won't work -and high QTS is very important
Click to expand...

Bummer....
Well, there no way I can have 4 x 12". The room is fill with furniture and WAF. Looks like I'll have to compromise on the bass and go for 2nd best. Which you think sound better consider I have a sub. 2 x 12" in OB or a ported 15" like JBL 2226H?

Thanks
 
Magnetar

Magnetar

Banned
Joined 2004
SamL said:


Bummer....
Well, there no way I can have 4 x 12". The room is fill with furniture and WAF. Looks like I'll have to compromise on the bass and go for 2nd best. Which you think sound better consider I have a sub. 2 x 12" in OB or a ported 15" like JBL 2226H?

Thanks
Click to expand...


I'd go with the JBL 2226 in a Karlson Klam!

The Klams kick major butt.

That woofer is one of the best 15's ever made. Low distortion!!

An externally hosted image should be here but it was not working when we last tested it.
 
J

JoshK

Member
Joined 2004
Hi Mike,

I've been reading this thread with great interest as your goals mirror my own and I like a lot of your choices in concessions (all speakers make them IMO).

Do you have any more details on your midhorns? I am really interesting in trying something similar. I'd like to try to model myself but would be interested in having something to compare to (confirmation, etc). Horns are quite new to me.

FWIW, the stuff I have to work with:
Lambda TD15X ( I have 3 due to a shipping accident, may get another soon)
JBL 2123H
BMS 4540ND
DDS ENG 1-90

The mid is the part I haven't pinned down. I'd like to experiment and try different things. I'd like to try a conical horn loaded Beyma 605nd for instance, maybe some other stuff. All OB of course.
 
R

riff.ca

Member
Joined 2005
Well I finally managed to order drivers! Ten 12" Madison Warriors on the way. :D

I'm told the 16 ohm versions are no longer available so I had to go with 8 ohms, bummer. I'm not sure the amp I have now will survive a 2 ohm load. I can borrow an amp from another system but that's got to be real short term. Not sure where I'll go with amps yet but if I buy new it will be a pro audio amp.
 
J

JoshK

Member
Joined 2004
For the mid driver, Mike is currently using the B+C 6PEV13? The Beyma's 6MI90 and Beyma 605ND look like they are similar. I wonder how they would compare. Certainly the B+C is cheaper, half as much as the 605ND.

What I think would kick-***, is building an elliptical conical horn, say 120º x 60º. It would take forever to build, but this is a journey not a sprint. Can hornresp calculate flare rates for conical horns? How about if the vertical and horizontal angles differ? How long would the horn have to be to have an Fc of 300hz, is the question I'd like to answer.

The shorter vertical dimension would facilitate closer center to center distances with the tweeter. But we are still further than ideal, I'd think. Oh well...sacrifices you must make.

I'm thinking about drawing up such a horn and seeing what it would really take to build it up from layers. :smash:
 
A

AJ

Member
Joined 2003
Hey Mike

Do you know of any sources for Madison other than ShredMusic? I bought their last twelve 12" Warriors and I don't want to wait another month to ghet the other 4. Google ain't much help.

Don't know about baffle construction yet, but I'm impressed with kitty liter filled. :)
 
Pano

Pano

Administrator
Joined 2004
Paid Member
A little treat for you fans of multi-driver bass.

Not OB in the least, but I bet it sounds great. Extremely efficient, too.

voie-droite-rugi.jpg


arr-grave-rugi.jpg



That's 6 horn loaded Altec 15" drivers per side, driven by a McIntosh 2600.


OK, back to OB. :)
 
O

OTMOPO3OK

Member
Joined 2004
Magnetar,
I cannot even express how much I admire what you are doing especially since my goals are so close to yours. I always read all your posts with greatest interest.

Have you ever heard/tried any of Hawthorne Audio Coaxials?

The woofer is custom made by Eminence based on Beta15 (i think).
The 1" compression horn tweeter in low-end model is Eminence ASD1001 ($20), and a custom Radian driver in the high-end model ($190).

http://www.hawthorneaudio.com/drivers.htm#SSI

I would be interested to learn your point of view on these.

I have the low-end model (the tweeter leaves something better to be desired) and was thinking of upgrading to higher-end Radian Tweeter but now I stumbled onto your thread. The only gripe is 2Khz dip due to bad driver matching I think. Hopefully Radian can go lower.

I also have their woofer Augie 15" with Qts 0.9 and I like the bass it produces very much on a simple 18" OB.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Top Bottom