Altec crossovers

[rontec]

Thanks GM
I appreciate the explanation and the procedure! I posted this also on the LH Site and got a good link for a ton of info, but your post gives me just what I needed. This should work out well for me!
BTW, I would have entreated my wife or daughter to help in this adjustment, but I think I alienated them from critical listening years ago.

[ZilchLab]

Just use an adjustable version of the bridged-T HF comp filter in Model 19, separately built by Altec as 30923. I have posted adjustable versions for both 8- and 16-Ohm variants elsewhere. It's all of five components to build one.

The PROBLEM with Valencia is that 806 does not have the requisite HF chops to credibly extend the response beyond ~13 kHz, and even there, the attenuated midband is running out of sufficient SPL to balance with the 416 woofer:

[Altec Best]

I thought the 30923/30904 was for matching a medium efficiency woofer to a high effeciency driver like the 411 when using a 416 that may not be needed is that correct Zilch. I just picked up a pair of 30923 with a set of 1285-8B crossovers.

http://www.lansingheritage.org/image...ome/page14.jpg

[ZilchLab]

30923 is M19 HF compensation standing alone, i.e., contoured EQ, way more than simple attenuation, to extend the high frequency response of the compression driver above mass breakpoint when used with controlled-directivity horns or waveguides.

Yes, there is some attenuation at the top, which may be adjusted via varying the value of C1, establishing the upper frequency from which the midband attenuation begins sloping downward toward lower frequencies.

Put it in Spice or mod yours to variable with an L-Pad's terminals 1 & 2, to see how it works....

JBL Technical Notes Volume 1 Number 11

[Altec Best]

Cool Thanks ! :2thumbsup: :thankU: