Sign in to follow this  
Followers 0
yamafied

Kpt-100

43 posts in this topic

Does anyone know the crossover frequency for the Kpt-100? I want to try some prefab crossovers to get rid of the "x-curve". If anyone knows how to mod the factory crossover to eliminate the "x-curve" roll-off, that would be welcome info as well.

Share this post


Link to post
Share on other sites

700hz. the clue is the coverage angle information....it' specific to the horn.

SPECIFICATIONS

COVERAGE ANGLE: Horizontal 100(o) (+-)10(o) 700Hz-15kHz (br)Vertical 100(o) (+-)30(o) 700Hz-15kHz

DIMENSIONS: 21.25" (53.9cm) x 11.5" (29.2cm) x 12.5" (31.8cm)

DIRECTIVITY INDEX: 7dB (+-)2dB 700Hz-15kHz

FREQUENCY RESPONSE: 65Hz - 14kHz(+-)4dB

MAX CONTINUOUS OUTPUT: 113dB

NOMINAL IMPEDANCE: 8 ohms, 4.1 ohms minimum at 200Hz

POWER HANDLING: 100 watts (20V) 40Hz - 10kHz

SENSITIVITY: 96dB @ 1 watt/1 meter

WEIGHT: 26 lbs. (11.8kg)

Share this post


Link to post
Share on other sites

Thanks for the information. Among commonly available "prefab" crossovers, 800hz two ways seem to be common. Would this be a good choice, or am I missing something?

Share this post


Link to post
Share on other sites

post a new thread with a title of X-curve mod for kpt-100. someone has done it. there was a flood of kpt100's and 200's here on the forum last year.

Share this post


Link to post
Share on other sites

Thanks for the response, however, I might be even more confused now. If the 3000Hz is correct, I will have more (cheaper) options in terms of passive networks. That does seem a bit high to me though. I am pretty sure that mine do have the x-curve. I have to push the levels 3-5db's up in comparison to my other Klipsch speakers (that are of the same era and have the same sensitivity) to get them to blend well. Even then, the highs and lows just don't seem like they are there.

Oddly, I also got an email from Klipsch support this morning stating that it was 65Hz, which definitely can't be right. I assume the rep thought I was asking where to cross my sub over, but even then, the low end for the KPT-100 is 75Hz.

Surely with the number of these things that seemed to have been dumped on to the market in the last year or so, someone has tackled this project. I will have to take Speakerfritz's advice and create a new post. I tried to put this in the correct place (Pro), but maybe somebody in the consumer area has done this.

Share this post


Link to post
Share on other sites

There are different crossovers depending on what version of KPT-100 you have.

Have you got numbers on the crossover and/or can you take pictures of the crossovers?

miketn

Share this post


Link to post
Share on other sites

There are different crossovers depending on what version of KPT-100 you have.

Have you got numbers on the crossover and/or can you take pictures of the crossovers?

miketn

The xover says "KPT-100D". I am trying to get a pic posted. If I can't, please use the following link:

http://imgur.com/FHmZN

Posted Image

Share this post


Link to post
Share on other sites

I was just sent schematics from Klipsch for the 100A and 100B networks. My xover has the same LF caps as the 100B, but that's about all that I can recognize.

Share this post


Link to post
Share on other sites

Ok, so after having brushed up on my schematic reading skills, I would say that this "KPT-100D" that I have must be the same as the 100B. The part that confuses me is the number of resistors. Everything else seems to match up. I am now analyzing this to determine what I could pull out to defeat the x-curve. My thoughts at the moment are that getting rid of the 15uF cap and the .4 mH inductor might do this. I would be grateful for any input that any of you might have. This is not my field of expertise by any means.

Posted Image

Share this post


Link to post
Share on other sites

Here is the KPT-100-D schematic.

I've not tested this myself but I would suggest you try to bypass the .3mh coil and the 7ohm 25watt resistor(or reduce it's value) in the tweeter circuit. This will give you the most high frequency extension. Note: the (RXE 075 and Parallel 200ohm 25 watt resistor) is the poly switch protection circuit for the tweeter and if you want to test it listen at a moderate level and temporarly short across it and listen for any significant spl increase (A significant spl increase would indicate it's value has changed and is out of spec).

The (1.1mh/15uf/7ohm 25w series RLC circuit) in parallel with the woofer is centered on 1239Hz with a banwidth of 1012.8Hz so this results in a reduction in this region. If you take this circuit out listen to vocals especially and see if it is perceived as better or worse.

Without doing some acoustical testing this is my best suggestions for you to try.

miketn

post-14473-13819801126436_thumb.jpg

Share this post


Link to post
Share on other sites

They look the same as mine. If you figure out how to do it, let me know. I have 4 of them I'd mod.

post-15193-1381980113159_thumb.jpg

Share this post


Link to post
Share on other sites

Here is the KPT-100-D schematic.

I've not tested this myself but I would suggest you try to bypass the .3mh coil and the 7ohm 25watt resistor(or reduce it's value) in the tweeter circuit. This will give you the most high frequency extension. Note: the (RXE 075 and Parallel 200ohm 25 watt resistor) is the poly switch protection circuit for the tweeter and if you want to test it listen at a moderate level and temporarly short across it and listen for any significant spl increase (A significant spl increase would indicate it's value has changed and is out of spec).

The (1.1mh/15uf/7ohm 25w series RLC circuit) in parallel with the woofer is centered on 1239Hz with a banwidth of 1012.8Hz so this results in a reduction in this region. If you take this circuit out listen to vocals especially and see if it is perceived as better or worse.

Without doing some acoustical testing this is my best suggestions for you to try.

miketn

Thanks for this! This is exactly what I was looking for.

Share this post


Link to post
Share on other sites

Carl sent me one of his KPT-100s so I could do some testing on it. First here is the FR of the speaker stock.

Bob Crites

post-9312-13819802526938_thumb.jpg

Share this post


Link to post
Share on other sites

The added jumper I show here will extend the highs.

Bob Crites

post-9312-13819802531042_thumb.jpg

Share this post


Link to post
Share on other sites

Here is a trace of the FR with the mod in place.

Bob Crites

post-9312-13819802533092_thumb.jpg

Share this post


Link to post
Share on other sites

Implementation is pretty easy. Just a short jumper wire soldered in place will do it. Here is a picture of the added wire. Just clip the wire and the crossover is back to stock.

Bob Crites

post-9312-13819802533782_thumb.jpg

Share this post


Link to post
Share on other sites

One more thing, the diaphragm used in the HF is a soft poly dome type. It can be replaced with a titanium for some even better highs. I tried that and if mine, the titanium woud definately be used.

Bob Crites

Share this post


Link to post
Share on other sites

Can't wait to hear them. Did you run a graph with the different tweeters or just listen to them?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0