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View Full Version : Crossing 2235 and 2121 at 290 Hz --> why?



spwal
12-26-2007, 08:55 AM
Hello,

I have searched the forums extensively and could not find much information on this subject.

has anyone used a different crossover point?...

The xover i will ultimately purchase will most likely have 24db slope.

Is the crossover point going to be dramatically different for using the 2122H and a 2123 midbass unit (down the road perhaps)?

Thanks and happy holidays,

spwal

pos
12-26-2007, 12:01 PM
The 2123H was crossed at 340hz in the 4344mkII :
http://www.lansingheritage.org/images/jbl/specs/pro-speakers/1997-4344mkII/page2.jpg

spwal
12-26-2007, 01:30 PM
Thanks,

I probably wont be getting the 2123H anytime soon though. Good to know for future reference.

Robh3606
12-26-2007, 01:31 PM
What crossover are you planning on using?? I use 24db slopes with a 2123 at 300Hz. Have used the same set-up with a 2122 as well and aside from the sensitivity differences I didn't have an issue with the crossover point.

Rob:)

spwal
12-26-2007, 01:35 PM
Thanks.

Hope things are well on moya, good luck finding any chocolate. hope i catch your reference otherwise you are probably wondering what im talking about.

Im going to be using the cc networks that you saw over at ak at the beginning of the month for the top 3 driver and for the 2 way active crossover, its still undecided though someone now has suggested that he can build me a rod elliot 2 way which im excited about. Its gonna take more time though.

i think that the crossover point on the rod elliot is not user serviceable--it is fixed, so i want to get it right. it is a lr4 xover.

Robh3606
12-26-2007, 02:43 PM
good luck finding any chocolate

Dargo and Chiana went down to the commerce planet. I am stuck here with Rigel.

So you got the CC from there. You could use a JBL M552. It will work fine until you get it all sorted out and you can E-Bay it when you are done. They are very reasonably priced used.

Rob:)

spwal
12-26-2007, 03:10 PM
I could get the ashly afterall in the meantime, for 240 new, its not the end of the world, but i like to pinch my pennies. I am having a difficult time finding appropriate used crossovers in the meantime.

to my knowledge, the cc network that you commented on in ak in the large wooden box uses the same values as the one posted up here and i assume is identical to what you have in your system.

hjames
12-26-2007, 03:36 PM
Is the Ashley an easily tunable crossover?
And just for archival porpoises, what model number is it we are talking about?

(After all, someone else may come along and want to do the same thing at some later date ... sharing is caring!)




I could get the ashly afterall in the meantime, for 240 new, its not the end of the world, but i like to pinch my pennies. I am having a difficult time finding appropriate used crossovers in the meantime.

to my knowledge, the cc network that you commented on in ak in the large wooden box uses the same values as the one posted up here and i assume is identical to what you have in your system.

spwal
12-26-2007, 03:44 PM
please see this ashly thread, which i revived from its quiet resting place...

http://www.audioheritage.org/vbulletin/showthread.php?t=2316&page=5

quite a few people here seem to like the Ashly. It seems great. Was trolling for a used one on ebay...

Please see the link below for the Rod Elliot 24db crossover

http://sound.westhost.com/project09.htm

quite a few people in diy-land swear by it....

boputnam
12-26-2007, 05:08 PM
Is the Ashly an easily tunable crossover?Yes - infinitely so.


....what model number is it we are talking about?I would imagine the XR1001 (http://www.ashly.com/product/xr-series-2.htm[[COLOR=royalblue) - this is a stereo two-way, equivalent to the M552 Rob mentioned.


...quite a few people here seem to like the Ashly. It seems great. It is a good device, particularly at this price point. It is reliable and easy to use. (I actually carry around a XR1001 loose in-case my DSP would ever fail in my SR rig(s). I could go mono three-way in a pinch and get through the gig without too much hassle...).

subwoof
12-26-2007, 09:09 PM
I started renting SR gear in the late 70's and the new company in the next city ( ashly ) down the thruway made one of the first affordable adjustable crossovers and we used a pile of them.

They were the ONLY brand on the market that had the "notch" filter adjustment that allowed you to tame the inevitable nasty crossover peak when using those big horn loaded 15 projection cabinets and radial horns. Since the truck pack was different for every club, the PA had to adapt.

They held up pretty well and I still have one kicking around somewhere ( and a 553 ) for backup when the processors crash or programming them is not an option without a computer handy.

But they do suffer from that german disease, mitknobbenpoken. When presented with a multitude of knobs ( or sliders on a graphic ) someone is bound to "improve" and that cute "divide by 10" push button has sent many a diaphram to the promise land.

If you need a crossover for the 434X monitors, setting it at 300 ( and getting it to exactly match the other channel ) will require an oscillator and scope. AND then safeguarding the controls.

For the old nightclub installs we would replace the crossover adj pots with internal trimpots ( or relocatem them inside ) so the Dj couldn't mess up the overall EQ.

sub

boputnam
12-27-2007, 09:12 AM
...When presented with a multitude of knobs ( or sliders on a graphic ) someone is bound to "improve" and that cute "divide by 10" push button has sent many a diaphram to the promise land.

... setting it at 300 ( and getting it to exactly match the other channel ) will require an oscillator and scope. Yea they do attract tweakers. But, if this is your home system where no-one fusses with things 'cept you, it will be fine.

As sub mentions, the decals on the face are imprecise. To tune the crossover point exactly will take measurement gear (oscillator, RTA, etc.) but is easy to do. This "feature" is not unique to the XR-series - all adjustable crossovers are the same (unless they have detents at the frequency but none do that I know of...). You can get damned close as it is.