Jump to content

How to make the RP-160M come alive!


Tweaker256

Recommended Posts

Hello everyone, I am new to the forum but not unfamiliar with Klipsch. A good friend of mine has 2 pair Heresy’s, 2 pair Cornwall’s and a pair of Khorn’s. I have replaced crossover caps in all of them and the original diaphragm’s in one with Ti.

After looking at a number of small speakers to replace a pair of tweaked NHT Super Zero’s I finally picked up a pair of RP-160M’s. I used to build speakers when I was younger, everything from cabinets to crossovers. My brother and I would use our front yard as our anechoic chamber laying the speaker down on the grass facing up into the atmosphere to do near field measurements for mechanical phase correction etc.

I knew looking at the horn design in the RP series it had potential, compacted rubber coating on the Tractix horn to eliminate resonance? Who does this? Only Klipsch. The 6.5" Spun Copper Cerametallic woofer is nice and tight as well, very rigid and light weight. Klipsch did an amazing job with these drivers. They have serious potential!

After listening for a few days I thought they should have had a little more clarity in the high frequency and upper midrange so I pulled the crossovers and sure enough to hit the targeted price range Kilpsch used a relatively inexpensive poly cap in the tweeter, a sandcast resistor and an electrolytic cap in the woofer circuit. These had to go.

Stock crossover

I ordered a pair of Jantzen Cross Caps to replace the Klipsch 3.9uF ones and put a couple of ceramic disks that I had lying around across the 43uF electrolytic, stage 1 complete.

Stage 1 upgrade

Stage 1 upgrade

Now the horn is coming alive! This made an improvement in the high frequency clarity that let me know I was right about these drivers and moving in the right direction.

Next step was to replace the 43uF electrolytic with Jantzen Cross Caps, the 9ohm sandcast resistor with a Mills type and add some 0.1uF Audyn True Copper bypass caps.

Stage 2 crossover

But that required rebuilding the crossover boards, 43uF of poly cap is too big for the pcb behind the binding posts. I purchased a 3.5" wide x .25” thick Poplar board from the local hardware store and rebuilt the simple crossover. I used Velcro to attach it to the bottom of the speaker housing.

Due to the size of these speakers the crossovers needed to be very compact and as it turned out the positive spade terminal on the inside of the binding post had to be rotated 180 degrees so it didn’t touch the crossover. I arranged the crossover so the upper binding posts go to the tweeter and the lower to the woofer circuit.

Stage 2 installed

I added a little constrained layer dampening (peel and stick type) to the Tractrix port for good measure as well, it is plastic and it dose ring a bit when you tap on it.

Rear Tractrix Port

Rear Tractrix port

You think they imaged before? Holy crap, the clarity will blow you away!

It turns out I was correct in my assessment of these drivers. This horn is the finest Klipsch has ever designed, the culmination of years of thought and research and probably reading these forums to find out what all of you have been doing to their speakers.

The balance, linearity and amazing clarity from the Ti diaphragm and the Cerametallic woofer are astounding. Every bristle of the brush on a snare drum is individually defined. Voices have an airiness to them and each instrument is individually discernable.

For this price these are unbeatable.

By the way I stole them for $299.99 and free shipping from ebay, brand new in the original boxes!

I probably spent $150.00 or so on the crossovers alone bringing the total around $450.00.

A great deal on speakers with such potential.

Edited by Tweaker256
Edited for clarification.
  • Like 7
Link to comment
Share on other sites

I love this!! awesome work.. I have a ton of RP equipment and would love for my equipment to sound even better than it already does.. is this something easy most people could do with guidance from someone such as ur self from over the internet? I know how to solder and have a very nice propane torch soldering gun made for electronics with many different tips..

  • Like 3
Link to comment
Share on other sites

Thanks everyone, if you can solder it's really not that hard. You don't need to go to extremes like I did to get much better sound from the RP series of speakers. I only replace what was already there with better components.

That killer horn tweeter's crossover consisted of a 9 ohm 10 watt resistor and a 3.9 uF cap in series with the + side and a 0.36 mH inductor across the + and - in parallel, that's all.

The woofer crossover is even easer, a 1.4mH inductor in series with the + side of the woofer and a 43uF cap across the + and - in parallel.

Remove the sandcastle resistor and replace it with a 4 ohm and a 5 ohm 12 watt Mills resistors soldered in series to make a 9 ohm, you can't buy a 9 ohm Mills resistor.

Now you have many choices from easy to complete rebuild. You can remove and replace the 3.9 uF cap in the tweeter circuit or bypass it, I choose both, the easiest would be to bypass it with a 0.1 uF Audyn True Copper Cap, yes that will increase it to 4 uF but that is only a 2.58% increase still within the manufacturing tolerances. Next bypass the 43uF cap in the woofer circuit with a 0.1 uF Audyn True Cooper Cap, that is the quick and dirty approach. Bypass means solder across in parallel. You will get 95% better sound.

Replacing the 43 uF cap requires rebuilding the crossover due to its size. You need to buy a 39 uF, a 3.9 uF and a 0.1 uF cap in parallel.

You can get all the above parts from Parts Experss for about $60.00.

Link to comment
Share on other sites

Correction the parts listed will cost about $90.00.

A less expensive alternative would be to use Jantzen Superior Z Capacitors at $10.18 each, that would cost about $60.00 for the whole project.

Nearly the same sound quality, clearity and imaging but for less money.

Link to comment
Share on other sites

  • 6 months later...

Tweaker256

 

I would like to try the same with these speakers, do you have a diaphragm for the stage 2 It´s a little difficult to see where the different components are soldered / connected to. Is it necessary with the the bypass caps, and what is their purpose? 

 

i have found this one from mills isnt that close enough 9,1 ohm  (RES-M1175) - 9R1 12W MRA12 Mills Resistor (9.1R)

Edited by muumit
Link to comment
Share on other sites

Looks like the Full Monty is now $142.20 at Parts Express.

I too think more could be gleaned from the horns on these speakers.

I'm going to start with the tweeter circuit. Replace the 3.9uF poly cap, upgrade the resistor and add a copper crossover cap. If I hear a definite improvement, I'll go further. I think I can mount these components in the PCB no problem. I pulled out one of my crossovers and it is tight in there, but this stuff can easily be mounted.

If not, I'll be out some cash. But right now I'm looking at a $2000 set of speakers to try to get a better sound.

These speakers have wonderful sound reproduction in the low and mids. Things start breaking up at the upper mids and highs.

This project might not begin for a few weeks. But I'll post the results here.

Edited by RP-160M
Link to comment
Share on other sites

  • 4 months later...
On 2016. 11. 12. at 2:34 PM, RP-160M said:

Looks like the Full Monty is now $142.20 at Parts Express.

I too think more could be gleaned from the horns on these speakers.

I'm going to start with the tweeter circuit. Replace the 3.9uF poly cap, upgrade the resistor and add a copper crossover cap. If I hear a definite improvement, I'll go further. I think I can mount these components in the PCB no problem. I pulled out one of my crossovers and it is tight in there, but this stuff can easily be mounted.

If not, I'll be out some cash. But right now I'm looking at a $2000 set of speakers to try to get a better sound.

These speakers have wonderful sound reproduction in the low and mids. Things start breaking up at the upper mids and highs.

This project might not begin for a few weeks. But I'll post the results here.

Hi! 

Any result in the project?

Link to comment
Share on other sites

  • 5 months later...

Anyone else tried this? Is it worth it? Just got a pair of rp-160m for stereo and I find them fantastic, but I could live with even more amazingness^_^

 

Edit: well I jumped in and replaced the 3.9uF with jantzen superior's. About 35 euros. They're too big for the pcb, so sticks out about 1cm, but it's still possible to put the crossover back in. Very easy if you have tried to solder before, and quite easy if you haven't:P

 

Sound is mindblowingly good! I thought these klipsch's were excellent before, and I can't say I can hear precisely what has changed (ears/memory not good enough for that), I can just say I can't stop listening  - have listened all spare time these last days, and I'm surely not finished. I trust Tweaker256 in that the highs have opened up, seems very reasonable. They image like crazy. The acoustics in my room is quite bad, but the sound is "in the room" as I've never ever heard anywhere before. Well maybe once, at a demo with big electrostats.

 

I agree that these speakers deserve the best crossover possible. 

 

I've ordered some 0.01uF mkt1837's,  they're much cheaper than the jantzens but I'm gonna try bypassing both pairs of caps anyway. And also get those Mills. Stage 2 might be too much for my skills, and Audyn's as bypass are too expensive for me right now.

 

Thanks so much to Tweaker256 for these ideas;)

 

If I could do it over, I would probably do as Tweaker256 mentioned in the last post. But those Superiors are beautiful:rolleyes:

 

IMG_0826.jpg

Edited by hkknudsen
  • Like 1
Link to comment
Share on other sites

  • 2 months later...
On 2017. 08. 29. at 10:08 PM, hkknudsen said:

I've ordered some 0.01uF mkt1837's,  they're much cheaper than the jantzens but I'm gonna try bypassing both pairs of caps anyway. And also get those Mills. Stage 2 might be too much for my skills, and Audyn's as bypass are too expensive for me right now.

 

Thanks so much to Tweaker256 for these ideas;)

 

If I could do it over, I would probably do as Tweaker256 mentioned in the last post. But those Superiors are beautiful:rolleyes:

 

IMG_0826.jpg

Hi! 

Any result in the stage 2? :)

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...