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How to make the RP-160M come alive!

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On 2/3/2019 at 5:41 AM, hello said:

That is the same crossover schematic that is used in the RP-160m with presumably different values.  IMO the thing that hurts the sound of these speakers is that massive cap across the woofer.  It hurts midrange quality.  

How exactly will that cap damage sound quality when needed to establish the crossover slope and keep the ringing of the woofer out of the mix?

Seems to me a higher order crossover might even work better though that would cost a lot more money in an inexpensive speaker.

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Unhook the tweeters and try different crossovers on the woofers.   Just listen to the woofers by themselves.  That large cap cuts the sound too abruptly.  It severely shrouds the sound of the midrange.  I think part of it is that the crossover point is too low but shunting all that sound to ground is never a good idea.  It's always better to add resistance to a capacitor across a woofer unless the capacitance is very small 3.3uf-4.7uf.    

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Magi,

I will try too get a picture later.  I am actually still messing with it and the parts are just hanging off the back of the speakers.   I have a lot of experience with sound reproduction but I am not a speaker builder. I have been messing around with these speakers for a while though.

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The only thing it's "shunting to ground" is information that's already been attenuated / phase-shifted by the inductor ahead of it and by design meant to be kept from the woofer.  What you're noting as more mid coming from the woofer without the cap is information that's going to be duplicated (though not entirely because of phase shifts) by the next driver up the scale.  But you're welcome to redesign the speaker any way you see fit; you do own it after all.

 

If you redesign the low-pass portion you'd do well to redesign the high-pass to match.

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On 2/4/2019 at 7:25 AM, hello said:

Magi,

I will try too get a picture later.  I am actually still messing with it and the parts are just hanging off the back of the speakers.   I have a lot of experience with sound reproduction but I am not a speaker builder. I have been messing around with these speakers for a while though.

 

Take your time. I look forward for your mod and see what kinds of sound improvement. I'm hoping your mod add more body or overtones for timbre, specially in midrange. From what I read so far, the brightness is a much easier fix with a resistor to crossover.

 

Are you also moving the crossover point higher like how Cauldron point out in his research to bring the midrange's presence forward?

 

Here is the comparison between JBL 590 and RP-8000F. I love the smoothness and dynamic of the JBL but not as alive as Klipsch. JBL's midrange is more nature with the right amount of body or overtones to the tone. 

 

 

Edited by Magi44ken

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Allowing the woofer to work out further in the frequency response by using a steeper slope may help the mid output.  Reduce the overlap between the drivers so the output in the crossover region may have more body provided by the woofer.  Just need to stay away from it's ringing.  Even a zobel to insure more accurate crossover slopes may be reasonable.

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Don't want to get so high with the woofer that dispersion narrows too much, though.  That'll mess with the balance of the sound power in the room.

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6 minutes ago, glens said:

Don't want to get so high with the woofer that dispersion narrows too much, though.  That'll mess with the balance of the sound power in the room.

Correct, though 6.5" inch woofer can go fairly high.  You'd likely be in the area where the woofer would start ringing before you had to worry about dispersion. 

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Magi,

Here's a pic of the modified crossover for the RP-160m. It sounds pretty good to me at this point but I still may make some changes.   The top red binding post goes to the tweeter and the top black binding post goes to the woofer.  The inductor is purchased from Crites and it is 1.35mh.  It makes a big difference in warmth and adds natural detail.  A simple first order is used on the tweeter.  I don't know what the acoustic performance is.  I increased the value from 3.9uf to 4.7uf.  An 8.2 ohm resistor is used to attenuate and smooth the frequency response. Without the inductor in the tweeter crossover the crossover frequency moves up so I increased the value to 4.7uf to get good transition from woofer to tweeter.  I found this value to sound the best.  The woofer crossover is the inductor bypassed by a 25uf capacitor with a 4.7uf capacitor across the woofer.  I don't know how to draw it or I would.  Of course, this is only to be used for private diy use, no commercial use is authorized.  

IMG_4252.JPG

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On 2/4/2019 at 9:15 AM, hello said:

Unhook the tweeters and try different crossovers on the woofers.   Just listen to the woofers by themselves.  That large cap cuts the sound too abruptly.  It severely shrouds the sound of the midrange.  I think part of it is that the crossover point is too low but shunting all that sound to ground is never a good idea.  It's always better to add resistance to a capacitor across a woofer unless the capacitance is very small 3.3uf-4.7uf.    

I don't think you understand how the crossover works.  When do you ever shunt everything to ground?

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I Never said the old crossover shunts everything to ground that would be a direct short.  That wouldn't be very good for an amp.  Hey you are welcome to your opinion, you might want to get your facts straight before posting though.  

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On 2/4/2019 at 9:15 AM, hello said:

Unhook the tweeters and try different crossovers on the woofers.   Just listen to the woofers by themselves.  That large cap cuts the sound too abruptly.  It severely shrouds the sound of the midrange.  I think part of it is that the crossover point is too low but shunting all that sound to ground is never a good idea.  It's always better to add resistance to a capacitor across a woofer unless the capacitance is very small 3.3uf-4.7uf.    

 

21 hours ago, hello said:

I Never said the old crossover shunts everything to ground that would be a direct short.  That wouldn't be very good for an amp.  Hey you are welcome to your opinion, you might want to get your facts straight before posting though.  

OK, well I must have been mistaken when you said "shunt all that sound to ground is never a good idea" and I said everything, meaning something substantial is going through the circuit, as sounded like implied.  Based on the reactance, that shouldn't be much power as the impedance of the combined circuit should be way up.  You need the cap to establish the proper knee and slope of the curve to get rid of the ringing.  So you do want to get that woofer out of the way of the tweeter so you don't have that noise in the way.

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@Hello,

BTW, a steeper slope would be nicer to provide a better midrange as you are correct in noticing.  Probably can't reach the proper price point doing that due to more crossover components but would probably make for a much cleaner presentation since I know those drivers are capable of more.

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I tuned it by ear.  So it may have some minor peaks and valleys.  It sounds better to me, a lot better.  I agree these drivers are very good.  Yes, I do know what the capacitor is for and also what it does to the sound.  When I said all that sound I was referring to all of the frequencies going through that capacitor instead of the woofer.  It cuts off some very important sound that the ear is very sensitive to.  I know the tweeter theoretically picks up where the woofer leaves off but it doesn't sound nearly as good as letting the woofer handle more of the all important midrange.  Among other things, my solution was to parallel  the woofer inductor with a large capacitor that extends midrange output.   I think the phase performance is better this way because the sound staging is better and the sound is more coherent. I have 30 yrs experience as a listener and 20 yrs in diy.  I play musical instruments. Everything I do is always evaluated according to musicality and sound. I am very sensitive to what real music should sound like.  Not trying to brag.  I have owned lots of equipment over the years and still do.  I would love for someone to try this crossover on their pair of Rp-160s and tell me what they think. That's the point of sharing diy, right?  Do you happen to know of any software that allows a user to post drawings of crossovers?  Is there a quick and easy way to do it?

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18 hours ago, hello said:

 That's the point of sharing diy, right?  Do you happen to know of any software that allows a user to post drawings of crossovers?  Is there a quick and easy way to do it?

Yes, I just wanted to make sure that people reading the post understood that very little power goes though that parallel cap as frequency goes up due to the inductor.  Just like folks label zobels as power suckers and robbing efficiency which isn't really correct.  Too much information is just thrown out and not understood nor thought about.

 

As far as free schematic software, it looks like digikey has something online.  https://www.digikey.com/schemeit/project/  Little funky how it works but has tons of symbols.

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18 hours ago, hello said:

  Among other things, my solution was to parallel  the woofer inductor with a large capacitor that extends midrange output. 

You might want to use something like DATS or woofer tester to measure the impedance.  Using a cap could cause some issues with the resulting circuit since you are effectively bypassing the inductor as the frequency goes up.  If a 12db per octave with a cap paralleled with the woofer, you would need something more for resistance on that leg of the crossover with the parallel cap.

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Good point.  An informal test was that one of my amplifiers, and Adcom 535, runs cool at full volume, with other crossovers I tried I could get it warm, which makes me think the speaker in it's current configuration is pretty easy to drive.   Maybe the impedance of the woofer goes up in the frequencies where the capacitor is active.   Thanks for the suggestions.  I thought about adding a small value .22-.33ohm resistor in front of the capacitor to match the inductors resistance.  But I can usually hear resistors so I hesitated doing so and don't have any on hand anyway.

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Hi all,

 

First of all, let me say I absolutely adore the 160s! Those babies totally changed my perspective on music and opened my ears! I had high expectations when I first bought them, but this !? Never expected this much!!! You all probably know what I'm talking about anyways . The gorgeous horns and low end warmth and definition made me start hoarding amplifiers of all sorts and powers and topologies etc...it's a very long story and a journey.

 

Now, I wanted to give my 2c regarding this topic: "for the love's sake of klipsch! please stop bypassing that LF electrolyte". For those of you who did it, I dare you, it's probably been some time. Please just remove them and listen again, at least out of curiosity.

 

I couldn't resist with this mod given all the awesome feedback and went with 3.9uF Jantzen CrossCaps for the HF  (great result) + Audyn mkp-qs 0.1uF as a bypass on that electrolyte in parallel (absolutely sacrilegious effects) it was as if somehow you've put a veil on the upper mids! Incredible!.

 

From my experience the vocals instantly lost that succulent lively presence and sweetness due to the bypass caps. I kept them for 5 days but just had to remove them because the messup was so striking and immediately audible and as obvious as was the revelation once I removed them. It is only at this point that I was able to hear improvement coming from the 3.9uF Jantzens, heck I was afraid I was gonna have to throw them out as well!

 

I have no Idea how is it technically possible because as it's just 0.1uF of capacitance added to the 43uF, but somehow it really disturbed the filtering of the upper range on the LF driver! Then again! no one actually knows and is able to confirm how is it technically possible that bypassing an electrolyte with a low value MKP or ceramic makes things better either... thus nothing indicates we shouldn't experience the exact opposite.

So please stand up if anyone has empirical knowledge on how bypassing caps make the sound better in this particular case. I've went searching through dozens of forums and threads on this topic, every single story comes short of common technical sense here!

 

OH. And please! For the love's sake, please stop putting ceramic caps into speakers! They have absolutely no place there and even in the amplifiers it is questionable nowadays. Have you never heard of how horrible microphonics are on those things? Actually ceramic caps are the worst passive components in existence when it comes to microphonics.

 

Anyways, hope you make something out of this and I'd love to hear what you experience with bypass caps and after removing them, if anyone is curious to do that.

Love.

Jan

Edited by KJAN

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This is great! I have been wondering about replacing my crossovers in my RP160Ms with a digital crossovers...just did not know what settings to use.
I also would like to upgrade the crossovers in my Rp150Ms too.

Sent from my SM-T550 using Tapatalk

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