Mt121 with hf horn inside

Need to make a very compact mid hi.
Have been looking at the b&c dcx50 coax mid/hf comp driver for a while and was wondering if I could hand it inside an mt121. The smallest horn I can find that will go down to 500-600 for the dcx is 315mm square . Will it interfere with the mt121 at this frequency?. I see Tony at Ass has done something similar with his 2x 12.
Second question , with the Mt121 only handling say 150-600 hertz, how directional will it be at those frequencies, what will it's horn actually be doing?

martinclaydon wrote: Second question , with the Mt121 only handling say 150-600 hertz, how directional will it be at those frequencies, what will it's horn actually be doing?

Who says the MT121 will only handle 150-600hz ?

Have heard MT121 run from 160hz to 1.6khz on many occasions.

Couple of weeks ago, had 4x of them config'd just like that, easily covering approx 400-500 people.

sorry you have not quite grasped the question, I WANT the dcx to handle 600 hz upwards therefore the question

martinclaydon wrote: sorry you have not quite grasped the question, I WANT the dcx to handle 600 hz upwards therefore the question

You're right.. Missed the context completely...

But before embarking on this project, have you heard standard MT121 with quality 12" + 2" drivers ?

Have heard coaxial setup in other cabs (Not Tony's), and it seemed the premise was more ease of use and economy, as opposed to quality and SPL.

no I have not heard one but it's reputation looks good.
I intend to use high quality b&c throughout
A 12" for the low mid and the two drivers in the bcx50 to handle high mf and hf
My aim was to make the mt121 as per design and put the coaxial driver inside the horn of the 12. This is purely to get the size of the unit down, do you think 2" have enough at very high hf , say 10 k +

.

martinclaydon wrote: do you think 2" have enough at very high hf , say 10 k +

My Favourite 2" is B&C DE85, which can give smooth 10K+ with slight eq'ing, followed closely by Beyma CP755TI (1.4")...

If you have the budget, other people favour Beyma CP755Nd, (Beyma 1.4") which really does sound rather spiffing.

it's been a long while since i owned any mt121's

has anybody attempted to boost anything above 900hz to reach a CD at say 1.5khz or 1.6khz?

i know rog's plots very clearly showed that these cabs drop off naturally above 900hz, and just wondering if boosting with eq starts to make them sound wooly and lazer like

i guess you're into phase plug territory then.

(mind you, a good 2" should really be able to play 900-1khz on a big horn really. have personally heard many do so.)

actually scrap that,

just seen this by Rog a while back:

The MT 121's 12" horn would have nearly kept up with the porn horns if it had a phase plug. You can see its response below 400Hz is good, but it drops below this. Theres still more output around 1KHz though with the MT 121 12" horn and with its lower 1.7KHz crossover point the 12" horn nearly met the 2" driver. I quite liked the sound of the MT 121, but its poor HF extension was evident and made it sound a bit flat. Distortion was also high with the P audio 2" driver. The MT 121 was also quite loud, but I think you would need 2 to keep up with 1 porn horn v2.

and thinking about it carefully, when i did have mt121, i think i used to cross higher than 1khz anyway with no major problems - i think as high as 1.6khz at times depending on how i was feeling smiley36

lev did you not hear my mt121's at the last speaker meet......

the 12" horn as very little to do with the direction of sound, this is due to the freq, the hf has the overall say on direction....