Jump to content

Introduction


Recommended Posts

Hello Community Members.

 

My name is Georg and i am from Vienna, Austria.

 

I bought my first pair of KG 3.5s in the late 90's and i am a huge fan since then. It was my pleasure to meet Valerie and Paul a few months later at the Klipsch factory during an US trip with a friend of mine. KG 5.5's, a KSW 150 and a KV-1followed right after that to complete my 5.1 setup which i used with different amps from NAD (stereo music), Pioneer and Denon (both home theatre) in a dedicated room with 20 square meters in the cellar of our house. Last year i decided to upgrade to UHD and 7.1, so i started to look for a pair of second hand .5 speakers. Finally i found a pair of KG 2.5 with an additional KG 2.5 with a broken crossover (broken cap) and no connectors at the end of some cables. At that time i had no idea how a crossover works, and i never soldered successfully before. So i looked for a second hand crossover, found it, bought it and brought it with me, when i did a business trip to the US April last year. The crossover worked fine, so i used one of the KG 2.5 to replaced the KV-1 which never satisfied me completely. At this point is have to say that i am NOT an Audiophiliac, so i hear the difference up to a certain level but not beyond, which i believe is good, because it limits the amount of money i have to spend to reach the level which satisfies me and also the other members of my family.

 

OK, so far so good. The question is now why i write this all into the Technical/Modification Forum and not somewhere else.

 

Well. I am a little bit a tinker, usually working with wood. The same time i also love it to learn new things (without any pressure - if possible). So i started researching on the internet, mainly reading articles here in this Forum, bought a soldering iron, a multimeter and some spare parts, to repair the broken KG 2.5 crossover - which i did successfully in the meantime. Maybe for some others this would have been enough. For me such a thing is always a starting point, but the real inspiration came from reading this article written by a gentleman from Australia: https://community.klipsch.com/index.php?/topic/168930-kg-55-update/&tab=comments#comment-2382772

 

What he wrote inspired me that much, that i decided to give my beloved family of speakers a new heard, by replacing the WHOLE crossover of all of my KG's. So i bought new Dayton caps as well as the new Jantzen coils and resistors, all with the specs as close as possible to the existing values for two 5.5's, two 3.5's and three 2.5's. But this also means that i need new crossover boards to fit the (compared to the original) much bigger new parts, but the current PCB of the the 5.5 and 3.5 fits EXACTLY the hole of the cabinet. And then there is the question about the material used for it. First i thought to make them out of wood, but this would be too easy ;-) and i do not want to have the cables uncovered at the "PCB". So there is the ned for something fancy, something new, something we do not have and which i have to learn to operate. After a short discussion with my wife i explained my youngest son (who turns 15 next month!!!) that he wants a 3D printer this year as his present - and he likes the idea! In the meantime, i learned how a 3D printer works and also Tinkercad, a software to build 3D models. Initially my idea was to make a kind of (Google says this is called) formwork, which then could be filled with concrete to make the board, but at the moment i believe i will print the board directly using carbon filament. This looks great and also eliminates an extra step - and therefore reduces the amount of possible issues. So i will start with it and will eventually try the concrete stuff later on. And this is the situation at the moment.

 

End of the introduction. Before i start the technical part i would like to ask all interested persons reading this to be a little bit patient with me. My native language is german and not english, so it is easily possible that what i write is hard to read for some of you. Second, i am not a technician and i have no experience with electronics or speakers at all. I started learning those things in my spare part a year ago, so i am sure SOME stupid questions will follow very soon. Third, we have 5 children, so please forgive me in case i do not reply here within a few hours or even days.

 

But now.... let's dig a bit deeper. Status quo based on the setup written above: All works fine, even the speakers are older than 20 years. One KG 5.5 sounds a bit strange sometimes, so i flipped the woofers of all 5.5's and 3.5's 180 degrees. No difference so one K-1023-K seems to be broken. Checking it i saw, that the rubber ring (we call it Sicke) is loose, so i will fix that first before i think about a replacement.

 

I measured the resistance of all speakers just for fun and replaced the Ferrofluid of all Tweeters with new one from FerroTec. Hope this comes close to the original one. In addition is started to replace some of the cables i used, mainly for optical reasons and also to add banana connectors to the setup. For the woofer i bought a new cable and soldered good cinch connectors on it. Works great!;-) Regarding cables and connectors. I use pure copper cables to connect the speakers to the amp and gold plated connecters at all terminals. For the connection from the terminals to the crossovers and to connect the parts of it, i will use silver plated copper connector and cables (AWG 16). If someone would recommend to use something else, please let me know.

 

KG 2.5: I already repaired the broken 2.5 crossover by replacing the four caps and by re-solder one coil, where the cable was broken right after that PCB. This works and i am happy with the result, even i do not need it. I also took the chance to measure the values of three of the old caps (the fourth will follow soon) and they have been very close to their original values. I also measured the new caps before i soldered them to see the difference. Surprisingly there has been no big difference. I re-foamed all 3 cabinets, because the old foam smelled bad and the shape was ..... well - please see the pictures. Btw, i can upload only 2MB so i made a pdf with all the pictures. Hope this works for all of you.

QUESTIONS:

1. One of the crossovers has an extra element connected to the + input cable. Does someone know what it is good for?

2. I will make the crossovers based on the schematic i found here on the forum. This schematic has the inputs and ONE output per woofer and tweeter, but the crossover has TWO outputs for the two woofers. Does it mean that i will use the same output, or do i have to split the output somewhere. Parallel or serial is the right question here i believe. My 5.5's have the two woofers serial connected. I believe it would be wrong to do the same with the 2.5's, right?

Coming NEXT: The 3D model is done, so i have to wait for Benjamins birthday to show him how to use his new 3D printer;-) so i can go further to make the new crossovers.

 

KG 3.5 and 5.5: Besides the problem with the "rattling" K-1023-K they are working fine and the 3D models of the PCB's are done. Based on the 3D model i made a wooden prototype to see, if it will be possible to slip it into the cabinet, even it is much longer. I will test this asap.

 

As you can see, i already made approximately half the way of a journey where i already learned a lot, not only about snake oil but also about people sharing the same passion. I hope many of you enjoyed what i wrote above and maybe some of you would even like to join me to share at least a bit of my way, to make this trip successful. All the time you spend already reading this and all the time you will eventually spend to help me with my project is really appreciated.

 

Thank you

 

Georg

 

PS: I can not upload the pdf's but get an error that i can only upload 2MB where the documents have less than 1.5MB. Well, i will try this once i posted this.

 

 

  • Like 5
Link to comment
Share on other sites

Good morning.

 

This weekend i finished the PCB replacement (3D models) showing the "final" layout of the components. Could someone more familiar with designing Crossovers please have a look to check if the layout is OK. The silver items are the Iron Inductors, the orange items the Air Inductors, the black items the Capacitors and the green items are the Resistors. The little brown showing up at the KG 5.5 only, is the Polyswitch.

 

There are 2 small supports under each Capacitors which can not be seen on the pictures attached. All Inductors will be slightly lowered (by 2mm - air and 4mm - iron) into the PCB and fixed with stainless steel zip ties. Resistors will have no supports and will also not be fixed with zip ties. Besides those details i would really like to know if the layout is fine, because the original layout is quite different.

 

Thank you for your help

 

Georg

KG 2.5 3D 1.png

KG 3.5 3D 1.png

KG 5.5 3D 1.png

  • Like 1
Link to comment
Share on other sites

  • 1 month later...

Hi Georg,

First let me say I wish I could speak German as well as you can speak English! 

 

Second, I'm so glad you got some value from my long rambling and rather unscientific write up. At least you understand why I was compelled to do so. 😉

 

Next let me say that I am really intrigued by your printed PCB's as my current efforts with wood leave much to be desired (yes that is a happy stick figure by my 6yr old under that 10ohmn resistor) .....

 

1404967524_CrossoverLP.thumb.jpg.45acfb03d6cddcadff91376962641078.jpg

 

One small error I noticed in your first post is that you say the KG 5.5 woofers are series wired when in fact they are parallel. This is important as it will change the performance of the crossover and overall system efficiency and impedance.

 

I have had the great pleasure of working alongside some of your countrymen in Aus Georg, and if there's something that I really admired about them was their appreciation for precision. If my stereotyping is correct then you may want to invest in the Omnimic and DATS tools which will enable you to accurately measure all your speakers to really know how they are performing. Then its a relatively easy matter to model the existing crossovers and improve or alter these.

 

Before (or after 😊) you lay down your hard earned cash for measurement equipment there are a few choice sites around the web I would like to recommend to expand your knowledge a little, if I may: 

  • Zilch's crossover design thread "Flex your PCD Mettle" (PCD = Passive Crossover Design) is a wonderful place to start with all manner of jump off points to the fine art of crossover and speaker design which inspired my own SEOS based design
  • Paul Carmody's website is great for the beginner with some detail how to's and interesting designs includiong the famous Overnight Sensations.
  • Troels Gravesen lives just up the road from you in Denmark (everything is just up the road in Europe if you live in Aus!) and he does some really special builds. He also details his approach to upgrading some classics which I found very useful for my work on the KG's. I think I spent a month reading everything there. Good stuff.  
  • Wayne Parnam from Pi Speakers in the USA has some terrific white papers on crossover design basics at the bottom of this page. He is so very generous with his knowledge and very responsive to requests for information on the Audio Round Table forum. His original inspiration also came from some Klipsch speakers!
  • The XSim thread over on diyaudio.com is also a great source of how to do crossovers, particularly with XSim obviously but there is good discussion of the principles there too which are essential knowledge. I have had support there from Bill Waslo the designer of XSim and the Omnimic system, amazing!
  • The Omnimic user documentation is a great resource as it explains how to measure loudspeakers which is the key to "seeing" what your speakers are doing and the gateway to empirically improving them.
  • And last but not least Dr Geddes white papers are foundational and useful for sifting the Audiophile from the Audio-fool!

Finally there are a few talented and generous speaker designers that have posted how to videos on speaker design, measurement and crossover modelling:

 

Good luck and keep us posted!

Cheers,

Maz. 

 

 

Link to comment
Share on other sites

On 6/1/2019 at 12:35 AM, oldman4u said:

Do you have KG‘s or have you modified your speakers somehow?

Georg,

I have a pair of '81LS and just enjoy meeting and reading the comments on the Forum.  I'm strictly 2-channel w/a couple tons of albums.  lol  :)  

 

Enjoy the Forum!

 

Dave

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...