right i have recentley brought a new system comprising of mx 121rt's, mx 1200's, mx600's and finally sb121h's. i have 8 of each and 6 sb121h's. i plan to run the system with either the rt's or the sb121h's depending on size of venue/indoor or outdoors. could anyone give me some pointers on setting for the two configurations(reflex subs or horn loaded subs) like xover points,eq,delays? any help would be appreciated.
Hi Dean, I've just picked this up. Unfortunately, due to work load, I am not on here much at the moment. However, I can give you some useful info. I never used the horn loaded sub with the MX system, so I don't have any relative data for that. I originally had 50 K of what you have which turned out to be 16 cabs of each model, 600, 1200 121.
The x/o points were MX121ST up to 90 hz rolling off the bottom end at 30 hz. The bass came in with a roll off at the bottom end of 40 hz and crossed over into the mid at 150 hz. The mid came in at 150 hz and went up to 1.6 khz. The top came in at 1.6 khz and went out with an open end.
Time alignment was as follows. ( ms delay settings ) Sub = 2.010. Bass = 0. Mid = 6.510. Top = 7.009.
You will notice that the sub is overlapped with the bass. For me this is essential with these components. People with analogue x\os' can't achieve this with a single unit, so a digital is the all important thing. I never went went further than a 388 Omnidrive. Although this x\o only has 2 bits of eq per band, the system doesn't require any more. My own thoughts on this was that if your system needs for than 2 bits of eq per band, then the design of the system would be questionable.
These readings were obtained by using my Iasys machine, which is a dedicated tool for the job.
In the earlier MT system which is where the SB121 comes from, I didn't use delay times. Because the BS1200 that stood on top had the same horn path as the sub albeit, a little shorter. However, the BS1200 was placed in the appropriate position on top, usually, with the backs lined up. This position was obtained by putting a pink noise signal from a Spectrum Analyzer into both cabs and moving one against the other until the indicated level reached its peak. At this point I assumed the cabs to be in phase.
I hope this is useful to you. Let me know how you get on. Where are you located?. T.
thanks for the info tony, will put it to good use next outting. we are in swindon wiltshire just doing small nights around the town at the
moment but hope to get out abit more now we have a decent amount of high quality kit.
we have foolishley managed the blow six of the 1550 in the mx1200, i was just wondering if you could confirm
something i heard about the 1550 in the ass boxes had two cone glued together, as i need to order some re-cone kits and want to make sure i get it right.