modifying a heresy

[sunburnwilly]

Thanks everyone....... To restate my plan for my home audio room, 2 81' lascalas(got), 5 heresys(need), and a sub(got). Sure my center heresy could very well just stand upright. Of course there is no fun in that. There are plenty of used heresy parts as well as speakers out there. Most of wich have to be purchesed in pairs. With the extra parts I would like to design a 1-of-a-kind center channel speaker/box. I am just unsure about running 2 extra speakers off a heresy crossover. Thanks everyone....................hunt

sunburn......I live around park circle.........you should be able to here my lascals from there.......

Park Circle has got alot of cool old homes . Pretty nice comunity . I live between Hwy 61 and Hwy 17 in West Ashley . I can't seem to hear your La Scalas over here . Maybe the Ashley River is diffusing the sound . Then again I have a hard time hearing anything over my Belles and Hereseys . [H]

[DrWho]

Is the PM function not working! Note: I am not selling anything. The below is not my info. It is a book I purchased and showing it for personal gain only. Don't want any copyright people on my back.

Doc, here is info from Loudspeaker Design.

ftp://www.jwcullison.com/trash/Doc1.doc

Maybe I'm reading this wrong but a push pull config with Isobarik design shouldn't have the loss of dB. In fact I though it would gain.

Seems I was wrong about the sensitivity decreasing (I forgot about it being the same in a parallel arrangement) [] . Just keep in mind that the change in impedance will shift your crossover point.

(unless I have the math backwards; I think you could easily fix this by just moving up one tap for +3dB which would put the crossover point back to the same frequency....maybe one of the crossover geeks i mean "gurus" will chime in). []

Btw, don't go with arrangement #2 because it doesn't reduce the "odd-order nonlinearities" the way #1 and #3 do. The "clamshell" (#3) is easier/cheaper to build, but I would think #1 would have the advantage of becomming a shielded system??? (which would be great for a center channel under a CRT.)

As far as building a new speaker out of heresy parts...it seems to me like this is trying to reinvent the wheel.

For the record, doubling up on drivers will require changes in the crossover (the crossover points get shifted around with changes in impedance) and then the only "benefit" is that you get at the absolute most +6dB gain in sensitivity and maxSPL....but the original heresy is already capable of 121dB of relatively clean output, which is way more than overkill for a typical home environment (where 100dB would be considered extremely loud). So it begs the question of what is to be gained by attempting to properly implement multiple drivers...for the money, I think better options are available via some of the drivers over at www.partsexpress.com (in particular something like the Beyma CP25 and then one of the selenium MF driver/horn combos...or perhaps even a CTS Piezo tweeter).

[jwc]

Now your talking

I'm not worried about the crossover changes. I eventually can figure that one out.

If your trying to match La Scalas, then the High SPL may be what you want.

Doc, you can get the parts such as one K77, one K55 and two K33's for cheap. The cabinet cast would be cheap too. Whether this is all an advantage ot not is an area of debate. I think it would make a nice center.

jc