• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Converting Klispch RP-160M to Active Crossover - REW/Equalizer APO

paulgyro

Active Member
Joined
Nov 21, 2020
Messages
144
Likes
100
I recently started the the conversation of this Klipsch from passive to active, mainly just for the learning experience. Thus far I've removed the passive crossover and connecting the binding posts directly to the drivers. I am now designing the active crossover, tweeter first.

Here are the measurement of the raw tweeter (1/24 smoothing).


tweeter raw.jpg

Here is the target and predicated with the tweeter eq/crossover.
tweeter target and predicted.jpg

Anyone know how clean up the alternating wave between? 3k and7k? I've not had any luck.

I've exported these filters so they can be loaded into Eq APO, here is what they look like.

Equaliser: Generic
rp160m tweeter Nov 22
Filter 1: ON PK Fc 517.0 Hz Gain -26.40 dB Q 8.287
Filter 2: ON PK Fc 534.0 Hz Gain -18.70 dB Q 8.243
Filter 3: ON PK Fc 574.0 Hz Gain -11.80 dB Q 7.207
Filter 4: ON PK Fc 601.0 Hz Gain -19.00 dB Q 8.033
Filter 5: ON PK Fc 666.0 Hz Gain -16.90 dB Q 7.804
Filter 6: ON PK Fc 687.0 Hz Gain -11.60 dB Q 7.371
Filter 7: ON PK Fc 720.0 Hz Gain -11.40 dB Q 7.478
Filter 8: ON PK Fc 774.0 Hz Gain -15.40 dB Q 7.573
Filter 9: ON PK Fc 858.0 Hz Gain -13.40 dB Q 7.393
Filter 10: ON PK Fc 967.0 Hz Gain -13.00 dB Q 7.178
Filter 11: ON PK Fc 1029 Hz Gain -4.40 dB Q 6.985
Filter 12: ON PK Fc 1098 Hz Gain -8.70 dB Q 6.953
Filter 13: ON PK Fc 1330 Hz Gain -5.30 dB Q 6.612
Filter 14: ON PK Fc 2072 Hz Gain -1.70 dB Q 5.756
Filter 15: ON PK Fc 2445 Hz Gain -1.80 dB Q 5.166
Filter 16: ON PK Fc 3467 Hz Gain -1.60 dB Q 2.743
Filter 17: ON PK Fc 12812 Hz Gain -1.70 dB Q 2.828
Filter 18: ON PK Fc 17470 Hz Gain -1.80 dB Q 3.000
Filter 19: ON None
Filter 20: ON None
Filter 21: ON None
Filter 25: ON None

My important question here is will Eq APO not allow any signal below 517 hz to make it to the tweeter? It's important I protect the tweeter of course.

Thanks,
Paul
 

Doodski

Grand Contributor
Forum Donor
Joined
Dec 9, 2019
Messages
20,745
Likes
20,756
Location
Canada
I recently started the the conversation of this Klipsch from passive to active, mainly just for the learning experience. Thus far I've removed the passive crossover and connecting the binding posts directly to the drivers. I am now designing the active crossover, tweeter first.

Here are the measurement of the raw tweeter (1/24 smoothing).


View attachment 246123
Here is the target and predicated with the tweeter eq/crossover.
View attachment 246124
Anyone know how clean up the alternating wave between? 3k and7k? I've not had any luck.

I've exported these filters so they can be loaded into Eq APO, here is what they look like.

Equaliser: Generic
rp160m tweeter Nov 22
Filter 1: ON PK Fc 517.0 Hz Gain -26.40 dB Q 8.287
Filter 2: ON PK Fc 534.0 Hz Gain -18.70 dB Q 8.243
Filter 3: ON PK Fc 574.0 Hz Gain -11.80 dB Q 7.207
Filter 4: ON PK Fc 601.0 Hz Gain -19.00 dB Q 8.033
Filter 5: ON PK Fc 666.0 Hz Gain -16.90 dB Q 7.804
Filter 6: ON PK Fc 687.0 Hz Gain -11.60 dB Q 7.371
Filter 7: ON PK Fc 720.0 Hz Gain -11.40 dB Q 7.478
Filter 8: ON PK Fc 774.0 Hz Gain -15.40 dB Q 7.573
Filter 9: ON PK Fc 858.0 Hz Gain -13.40 dB Q 7.393
Filter 10: ON PK Fc 967.0 Hz Gain -13.00 dB Q 7.178
Filter 11: ON PK Fc 1029 Hz Gain -4.40 dB Q 6.985
Filter 12: ON PK Fc 1098 Hz Gain -8.70 dB Q 6.953
Filter 13: ON PK Fc 1330 Hz Gain -5.30 dB Q 6.612
Filter 14: ON PK Fc 2072 Hz Gain -1.70 dB Q 5.756
Filter 15: ON PK Fc 2445 Hz Gain -1.80 dB Q 5.166
Filter 16: ON PK Fc 3467 Hz Gain -1.60 dB Q 2.743
Filter 17: ON PK Fc 12812 Hz Gain -1.70 dB Q 2.828
Filter 18: ON PK Fc 17470 Hz Gain -1.80 dB Q 3.000
Filter 19: ON None
Filter 20: ON None
Filter 21: ON None
Filter 25: ON None

My important question here is will Eq APO not allow any signal below 517 hz to make it to the tweeter? It's important I protect the tweeter of course.

Thanks,
Paul
You should use blocking capacitors for the tweeters, Direct connection to the amp will be danger zone for them.
 
OP
P

paulgyro

Active Member
Joined
Nov 21, 2020
Messages
144
Likes
100
You should use blocking capacitors for the tweeters, Direct connection to the amp will be danger zone for them.
Do I just put this cap in line series? How do I determine that value to use. I assume this is going to be a high pass filter to keep frequencies too low out of the tweeter.
 
Last edited:

Doodski

Grand Contributor
Forum Donor
Joined
Dec 9, 2019
Messages
20,745
Likes
20,756
Location
Canada
Do I just put this cap in line series? I do I determine that value to use. I assume this is going to be a high pass filter to keep frequencies too low out of the tweeter.
Are these Klipsch 2 way or 3 way?
 

Doodski

Grand Contributor
Forum Donor
Joined
Dec 9, 2019
Messages
20,745
Likes
20,756
Location
Canada
Check out this diagram made by @dualazmak for his quad amp'd system plus active subwoofers. It shows the blocking caps and to put them in series. I ran a tri-amp'd system for some years and I fried a set of very nice tweeters because I was too staunch on purity and did not want to use blocking caps. Use them!
 
Last edited:

fpitas

Master Contributor
Forum Donor
Joined
Jul 7, 2022
Messages
9,885
Likes
14,191
Location
Northern Virginia, USA
Sometimes a series resistor will smooth out the response wiggles of a compression driver. But, not always.
 

sonitus mirus

Active Member
Joined
Apr 19, 2021
Messages
256
Likes
336
If there is danger involved, why not use a parallel resistor capacitor path and check on it once in a while, just in case?
 

RayDunzl

Grand Contributor
Central Scrutinizer
Joined
Mar 9, 2016
Messages
13,198
Likes
16,981
Location
Riverview FL
If there is danger involved, why not use a parallel resistor capacitor path and check on it once in a while, just in case?

Series capacitor blocks low frequencies, the main danger to the tweeter.

Parallel capacitor shorts high frequencies bypassing the tweeter.
 
Last edited:

Doodski

Grand Contributor
Forum Donor
Joined
Dec 9, 2019
Messages
20,745
Likes
20,756
Location
Canada
OK. Follow the video and do what he tells you to do or just use the chart he shows you in the video. Make sure you get bi-polar capacitors for the protection. If you can't get bi-polar caps then use 2 electrolytic capacitors but reverse the polarity so they are each connected opposite of each other so the power can flow both ways instead of one way. A bipolar cap is actually 2 caps in one package so it the same thing if you use two non-bipolar caps. Come back here if you need more stuff. :D
 

Rednaxela

Major Contributor
Joined
Mar 30, 2022
Messages
2,051
Likes
2,673
Location
NL
Why implement your crossover with PK filters instead of a HP one?

Also, wouldn’t one focus on getting the crossover right first and work on the overall response later?
 

Doodski

Grand Contributor
Forum Donor
Joined
Dec 9, 2019
Messages
20,745
Likes
20,756
Location
Canada
Why implement your crossover with PK filters instead of a HP one?

Also, wouldn’t one focus on getting the crossover right first and work on the overall response later?
Can you detail that idea a bit more? I'm not sure what you mean.
 

Rednaxela

Major Contributor
Joined
Mar 30, 2022
Messages
2,051
Likes
2,673
Location
NL
It was a question for the OP, looking at the measurements and the EQ APO corrections he has in mind.
 

Rednaxela

Major Contributor
Joined
Mar 30, 2022
Messages
2,051
Likes
2,673
Location
NL
I mean using Peace you can set up BW and LR filters right?
 

alex-z

Addicted to Fun and Learning
Joined
Feb 19, 2021
Messages
910
Likes
1,684
Location
Canada

You have way too many room reflections in your measurements for doing crossover design work. Get some gated measurements, even 4ms gating is adequate for basic design work if merged with near-field response for bass loading of the port + woofer.

Your current EQ setup makes no sense. You should be running a simple high-pass on the tweeter, and low-pass on the woofer, at roughly 1500-2500Hz. A lower crossover point yields better directivity in a 2 way design, but reduced power handling. Then use a series of peaking filters to give yourself an in-room response roughly matching your preferred target.

 
OP
P

paulgyro

Active Member
Joined
Nov 21, 2020
Messages
144
Likes
100
Why implement your crossover with PK filters instead of a HP one?

Also, wouldn’t one focus on getting the crossover right first and work on the overall response later?
Why PK filter? That's really a question for REW not me, I'm just using REW. All I'm doing here is a simple crossover, 8th order Butterworth at 1500 hz. Check out my settings, super simple. REW generates a target curve and then the needed filters that can be imported to any number of devices.
tweeter with crossover.png
 
OP
P

paulgyro

Active Member
Joined
Nov 21, 2020
Messages
144
Likes
100

You have way too many room reflections in your measurements for doing crossover design work. Get some gated measurements, even 4ms gating is adequate for basic design work if merged with near-field response for bass loading of the port + woofer.

Your current EQ setup makes no sense. You should be running a simple high-pass on the tweeter, and low-pass on the woofer, at roughly 1500-2500Hz. A lower crossover point yields better directivity in a 2 way design, but reduced power handling. Then use a series of peaking filters to give yourself an in-room response roughly matching your preferred target.

Thanks for the reminder to come back and take gated measurements. I thought I could get away on the tweeter not using gated as I have a treated room with a very low RT60 time. Once I get the active crossover design workflow down I'll loop back and learn how to take gated measurements to more take the room out of the equation.

As far as your comment about "You should be running a simple high-pass on the tweeter, and low-pass on the woofer, at roughly 1500-2500Hz", the simple answer is: I am! See my other recent post, I'm using an 8th order Butterworth @ 1500 hz. The rest is just how REW works. I'm open to someone telling me I'm doing something wrong in REW.
 

Rednaxela

Major Contributor
Joined
Mar 30, 2022
Messages
2,051
Likes
2,673
Location
NL
Sorry, what's Peace?
It’s a front end for EQ APO.

 
Top Bottom