UPDATE: Questions...

Posted by Presto (A) on August 1, 2012 at 12:01:20

In Reply to: JBL123-A/Klipsch 400 speaker build HELP posted by Cosmickat on July 28, 2012 at 13:20:20:

There is something strange here.

You have what seems to be an aftermarket / DIY / custom klipsch crossover copy. Looks like a B&K board or a copy of one (both use white sonicaps). B&K does custom Klipsch crossover replacements/upgrades.

So we need to know a few things:

QUESTION: If this is indeed a LaScala crossover, there could already be a high-pass filter in the midhorns crossover circuit in addition to a low-pass filter (if they even used one). After all, the LaScala was a three way and had a horn loaded woofer plus the two horns, right? And they would have HAD to put some high-pass circuitry on the midhorn else fry it or just make it sound terrible...

IF there is no passive high-pass on the midhorn, you are obviously (or should be) running a high-pass from the Urei for the horns. (THis is in addition to the low-pass you are running to the 123A's).

IF there *IS* a passive high-pass already there you need to do one of two things:

a) Remove it and use the Urei for the midhorn high-pass. (yikes)
b) Mirror the final acoustic response of the midhorn / midhorn filter combination. (This may or may not be do-able with the Urei)

Once a flat response is achieved perform the correct baffle step compensation/equalization. This is NOT do-able with the Urei because you want an ~600hz crossover point and the baffle step frequency is ~300Hz. There is no way to increase the baffle step frequency because you are limited by bass driver diameter. (Even going with a super-thin 12" wide enclosure will only increase the BSC frequency to 380Hz.) Baffle step in this case will affect the overall level of the mid-horn and tweet horn. Only the woofer response will need a "shelving filter". THis can be done passively, even if you're using the Urei (as an add on eq circuit) or it can be done actively. The Urei is the limiting factor here. You *could* use the UREI and do BSC by using TWO stereo channels for the bass. One you would cross over at 600Hz (the upper woof) and the lower woof you would cross over at 380Hz. The relative levels between the upper/lower woofers can then be adjusted to suit the amount of BSC you want. So two woofs is indeed an option.

You need to answer those passive filter questions, or post sufficient detail about the horn's passive crossover so this can be examined.

Cheers,
Presto

This post is made possible by the generous support of people like you and our sponsors:

Follow Ups Full Thread

Topic - JBL123-A/Klipsch 400 speaker build HELP - Cosmickat 13:20:20 07/28/12 (27)

UPDATE: Questions... - Presto 12:01:20 08/01/12 (1)

RE: UPDATE: Questions... - Cosmickat 16:50:42 08/06/12 (0)

RE: JBL123-A/Klipsch 400 speaker build HELP - Coytee 03:00:12 07/29/12 (9)

RE: JBL123-A/Klipsch 400 speaker build HELP - Presto 23:17:03 07/29/12 (8)

RE: JBL123-A/Klipsch 400 speaker build HELP - Cosmickat 08:58:52 07/30/12 (7)

RE: JBL123-A/Klipsch 400 speaker build HELP - Presto 13:32:57 07/30/12 (6)

RE: JBL123-A/Klipsch 400 speaker build HELP - Cosmickat 11:23:31 07/31/12 (3)

RE: JBL123-A/Klipsch 400 speaker build HELP - Presto 22:15:10 07/31/12 (2)

RE: JBL123-A/Klipsch 400 speaker build HELP - Cosmickat 10:18:18 08/01/12 (1)

If you want to get this really singing - badman 14:59:33 08/01/12 (0)

RE: JBL123-A/Klipsch 400 speaker build HELP - Cosmickat 19:17:16 07/30/12 (0)

re: "although JBL is likely going to have decent drive-unit consistency" - badman 14:37:03 07/30/12 (0)

On second thought......... - djk 20:40:34 07/28/12 (4)

RE: On second thought......... - Cosmickat 09:01:21 07/31/12 (3)

It would increase - badman 10:28:30 07/31/12 (2)

RE: It would increase - Cosmickat 12:28:46 07/31/12 (1)

RE: It would increase - Cosmickat 12:37:10 07/31/12 (0)

RE: JBL123-A/Klipsch 400 speaker build HELP - djk 17:59:09 07/28/12 (7)

RE: JBL123-A/Klipsch 400 speaker build HELP - Cosmickat 21:12:15 07/28/12 (6)

6k XO is awful high - badman 17:27:17 07/29/12 (5)

RE: 6k XO is awful high - Cosmickat 22:02:10 07/29/12 (4)

You'll get the impression of "More" in 3cu ft - badman 09:15:36 07/30/12 (1)

RE: You'll get the impression of "More" in 3cu ft - Cosmickat 12:17:33 08/01/12 (0)

RE: 6k XO is awful high - Cosmickat 08:43:38 07/30/12 (1)

Ah, that's a better point - badman 09:09:47 07/30/12 (0)

Do you have... - tube Tom 17:53:12 07/28/12 (1)

RE: Do you have... - Cosmickat 20:25:56 07/28/12 (0)

Follow Ups

UPDATE: Questions... - Presto 12:01:20 08/01/12 (1)

RE: UPDATE: Questions... - Cosmickat 16:50:42 08/06/12 (0)

UPDATE: Questions...

Post a Message!