2 Attachment(s)
902 & QSC with and without loading cap
I promised to do this a while ago. This is a 902 driver on QSC HPR 152i waveguide with loading cap (orange) and without (green.) Same driver. Crossover is 4 Pi.
Red is DE250 on same setup.
Attachment 55870Attachment 55871
Please, help with T-Filter
Quote:
Originally Posted by
Zilch
Here's the "T-filter" standing alone, top. Altec used it to provide supplemental HF compensation after some stock crossovers.
As you see in the M19 crossover, R2 may be varied to adjust the amount of compensation.
At the bottom here is shown a Zobel, which you'll also find discussed in Dickason, used to flatten the reflected impedance of the woofer as illustrated by Earl, above, so that the main filter behaves more predictably.
Yeah, 6.2 uF for C1 and 4 Ohms for R1s are fine. R2 and the Zobel components vary with the application. You can see that if R2 goes to a high value, providing the minimum of 6 dB compensation, it's basically 8 Ohms in parallel with C1, what I have suggested you try for starters here, as there's already some compensation in N800-F (maybe).... :yes:
Thank you for your posts related to this area of the Model 19 crossover. I have been trying to sort out the T-Filter and how it affects the high freq response.
I, too, am trying to 'clone' this crossover and use it for my own system.
The attenuation of my HF driver is fixed, however, not with using L-Pad potentiometer.
This crossover's use of potentiometers and T-Filters? or Step-Filter? confuses me.:banghead:
I am familiar with L-Pads or attenuation circuits but have not seen this topology for potentiometers.
How does the T filter functions here?
How does it affect the high frequency response?
I would like to boost the highest frequencies 4-20k and/or reduce the 'Shouty' mids 700-2k.
Is the T-filter simply wired as shown in the diagram?
I have loads of resistors - no pun intended - so I thought I would do some experimenting with it.
The driver I am using is an EV DH1 with FaiTal LTH142 Elliptical Tractrix lens: http://www.faitalpro.com/en/products...p?id=903020105
Thanks again for all the help.
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<img src="http://usr.audioasylum.com/images/5/54573/faital-pro-hf146-f-size475.gif">
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