Charge Coupled Crossover

[1audiohack]

Where does one go for an education on charge coupled crossovers?

What theory describes the benefits?

I want to start with a replacement project for my 3106's. A very simple crossover indeed.

I saw Zilch respond to one post on 3105's with "Build one your for $25, charge coupled for $10 more."

Cool, where do I start?

Thank you!

[Titanium Dome]

Read this thread:

http://www.audioheritage.org/vbulletin/showthread.php?t=3555

Focus on post #6.

[Titanium Dome]

Also, rather than retyping Ian's list, look at his post here with linked references back to these forums:

http://www.diyaudio.com/forums/showthread.php?threadid=87885

[1audiohack]

Thanks T.D.

That Gregory Timbers is one smart cookie!

Those three pages explain it perfectly.

Off to the electonics store, again.:D

[4313B]

That Gregory Timbers is one smart cookie!Ed Meitner passed the idea on to Greg and Greg incorporated the idea into his statement systems. This is one of two topics that should have stayed in the private forums due to it causing unnecessary fretting and confusion. :)

[MJC]

Ed Meitner passed the idea on to Greg and Greg incorporated the idea into his statement systems. This is one of two topics that should have stayed in the private forums due to it causing unnecessary fretting and confusion. :)
What confusion? It is the act of taking any XO, removing the original caps and replacing them with Solen polyproplyene caps of twice the size and always in pairs. Then connecting the positive side of a 9v alkaline battery to the common point of all pairs.
The result is a far superior set of speakers. The amount of money spent on CC networks, I spent about $150/ea to build completely new XOs, is well worth it.

[4313B]

What confusion? It is the act of taking any XO, removing the original caps and replacing them with Solen polyproplyene caps of twice the size and always in pairs. Then connecting the positive side of a 9v alkaline battery to the common point of all pairs.Yep! My point exactly! :yes:

The amount of posting it generated though was pretty funny to some I guess.

some cc networks in progress

[Earl K]

What confusion? It is the act of taking any XO, removing the original caps and replacing them with Solen polyproplyene caps of twice the size and always in pairs. Then connecting the positive side of a 9v alkaline battery to the common point of all pairs.
The result is a far superior set of speakers. The amount of money spent on CC networks, I spent about $150/ea to build completely new XOs, is well worth it.

- You forgot the 2 to 5 meg isolation resistor .
- FWIW, these batteries do represent fairly low impedance paths back to ground within the crossover circuit.
- If one omits this resistor / one then creates a lowpass circuit with an F3 determined by the cap values being used , as well as the working impedance for that portion of the circuit .


snip,,,, This is one of two topics that should have stayed in the private forums ,,,,,, snip

- The "cat getting out of the bag" preceeded the "May Forum" by a good nine months, if that's what you're referring to .
- Once Don McR posted those first links to Harmans' tech papers ( just previous to this current forum I believe ), questions started to be asked ( with all the attendant fretting following in due course )

- & Yes, this sort of stuff has definately kept me amused for the last 4 1/2 years .


:)

[4313B]

- This sort of stuff has definately kept me amused for the last 4 1/2 years .It just made me cranky. A few others I'd rather not see cranky too. Oh well. :p

[richluvsound]

They look as good as they sound ,and worth every penny IMHO. They move 30 year components into the 21st century. :applaud:

GT, 4313b , Guido , and the Aussie guru Ian The true masters of the black art. They dont charge enough considering the years of experience it takes to
build these things.

Rich

[MJC]

- You forgot the 2 to 5 meg isolation resistor .
- FWIW, these batteries do represent fairly low impedance paths back to ground within the crossover circuit.
- If one omits this resistor / one create a lowpass circuit with an F3 determined by the cap values being used , as well as the working impedance for that portion of the circuit .
:)
Yes, as a matter of fact I did, how silly of me.:banghead:

[4313B]

Yes, as a matter of fact I did, how silly of me.:banghead:Um.. You forgot to mention them? Or you forgot to use them?

[Earl K]

some cc networks in progress
http://audioheritage.csdco.com/vbulletin/attachment.php?attachmentid=29389&stc=1&d=1194723064

Nice.

:)

[MJC]

Um.. You forgot to mention them? Or you forgot to use them?
I used 'em, just forgot to mention them in that post.
Having the full applied 9v going straight to the caps, don't think I'd want that:eek:

[4313B]

They move 30 year components into the 21st century.Well, I would have to agree. I most recently finished six months with 4355's and I am sufficiently impressed with the results.

G.T. started all this way back when he modified a few pairs for some friends with 250Ti's. He did it the hard way and just modified the existing networks and we discussed that complete nightmare at length.

The goal has been to make them as painless as possible to bolt in place of the stock networks as well as to make them reasonably easy to ship. A top board goes in place to protect the caps and coils.

[grumpy]

A top board goes in place to protect the caps and coils.

Nice work/layout.

...figured that's what the standoffs were for. Plexiglass? or are these intended
for internal cab use? -grumpy

[Hoerninger]

The manual of a modern JBL speaker (guess which ;) ) at Harman shows charge coupling as well.

There are some patents which show ways of obtaining the DC voltage from the AC signal. I have found
1. KOSS Electronics Inc., Milwaukee - patent 3,632,903
2. American Technology Corporation, San Diego - patent 6,628,791 B1
3. American Technology Corporation, San Diego - patent 7,158,646 B2
obtained by http://www.pat2pdf.org/.
The ATC patents are nearly the same, for me Figure 9 has been most inspiring:
Stabilizing to ca. 3 V (1,1 W at 8 Ohm) and triblication.
____________
Peter

[Ian Mackenzie]

Hmmm..Someone's been busy. Nice work.:bouncy:

l'll bet that lot took a month of Sunday's to get it to that stage.:)

Ti Dome..I've long since stopped talking about this topic;).....controlling the random noise floor coming through the Inbox was just too much hard work...particularly when the guy says he only wants to spent $10 or porn is navy watch. ..bring out the violin....:blah:.

You guys just need to try it (CC).

For stock vintage owners its a step in the right direction .

Ian

[Chas]

:)4313B you have reminded me of a lttle bit of history, in case anyone is interested.

Ed Meitner is a true audio pioneer. I first met him in the early eighties when he was at Amber Electrodesign working with Wayne Jones. They had moved from making the Olive automated mixing consoles to new, radically better analog-based distortion analyser designs. Leading edge stuff back then, I still have one here and it performs like new.

I think the PC controlled Audio Precison product came in just after that and took over most of the market.

I had an opportunity to audition the prototypes of what was to become the Museatex line of electronics in the future at Ed's home. Ed also had just invented a novel way to interface MM phono catrtidges using them as a current, rather than a voltage, source.

I actually have a couple of DIY versions of this MM design that are still in use here today. They have remarkably low noise and very good sonic performance.

The first time I personally encountered CC caps was in a Ward Beck broadcast distribution amplifier from the late seventies. The design used tantalum coupling capacitors in the interests of saving PCB space and they featured DC biasing. The biasing was likely as a result of their inherent poor sonic performance in audio circuits. FWIW, a good example of this would be the Revox A77 which is full of tantalums. An A77 with better caps takes it to a new level of performance.

This would predate the famous Jung/Marsh arcticles in Audio by quite a bit of time.

I hope this isn't too OT.

[4313B]

I hope this isn't too OT.I don't think it is. Thanks for the post Chas. :)

http://www.emmlabs.com/html/about/ed.html

[markd51]

Just curious, are there people who make these charge coupled X-Overs for others in audioland?
Sounds interesting for my L-65's. Mark

[1audiohack]

OK, months ago I was looking at the network for the 4344MkII as it lines up with a project of mine, and was puzzled by the 9v battery.:blink:

My intent to build a CC 3106 is because I currently use them between my 2404's and 2425's on 2344's. I know what the 3106 sounds like, and as simple as they are it looks like a good place to test.

So let me see if I understand the theory behind this, the sign wave delivered from the amplifier is at its highest potential when the voicecoil is close to its peak, the point of least acoustical output. When the voicecoil accelerates back toward center, it is at maximum velocity and acoustical output as it passes thru center, at wich point the amplifier is currently at its lowest potential (pun intended) to control the coil motion. It is at this point the voltage crosses the zero line and the capacitor creates a step as it copes with changing polarity.

In short, at the point of maximum acoustical output the capacitor has the best chance to make itself heard.

So if I have it right, charge coupled caps for me.

I looked high and low for a thread on this subject as charge coupled crossovers, not capacitors, oops.

The 4344MkII scematic shows the 2.2m series resistor, I cought that, I just didn't understand the charged cap theory.

As for the quote"should have stayed in the private forums", what the hell is that all about?!?

I've said before, with out information sharing, we would still be hunting animals with sharp sticks.

Thank you for sharing.

[MJC]

OK, months ago I was looking at the network for the 4344MkII as it lines up with a project of mine, and was puzzled by the 9v battery.:blink:
In short, at the point of maximum acoustical output the capacitor has the best chance to make itself heard.
So if I have it right, charge coupled caps for me.

I looked high and low for a thread on this subject as charge coupled crossovers, not capacitors, oops.
Thank you for sharing.
Applying a 9v charge, thru high resistance(6 meg ohm), to the common point of two series caps keeps the audio signal from crossing the dielectric zero point of the caps, thus eliminating the phase shift.

[1audiohack]

Right. Thats what I got out of it.

Thank you.:)

[spwal]

Hi,

I dont think this is a dead topic at all. Why should this be a private topic? I am starting to sound storm-ish here, but there are plenty of people interested in this topic.

[jblnut]

Well, I would have to agree. I most recently finished six months with 4355's and I am sufficiently impressed with the results.

G.T. started all this way back when he modified a few pairs for some friends with 250Ti's. He did it the hard way and just modified the existing networks and we discussed that complete nightmare at length.

The goal has been to make them as painless as possible to bolt in place of the stock networks as well as to make them reasonably easy to ship. A top board goes in place to protect the caps and coils.


Welcome back 4313B ! Didn't recognize your new name and avatar, but I reconize your charge coupled 250TI networks every time I hear them :).

Glad to see you around these parts again...

jblnut

[spwal]

:bouncy:wow,

thats alot of deleted text. i thought this was a free country? :bouncy:

[hjames]

Do not confuse freedom of speech with the right to bar trolls ...

Buy your own server and You Too can have a free country ...
until the spammers try and take it from your cold hard fingers



:bouncy:wow,

thats alot of deleted text. i thought this was a free country? :bouncy:

[timc]

I'm Currently making a CC crossover for my L65's. I'll let you know how it turns out.


-Tim

[Domino]

I have a pair of L300's that I'm considering charge-coupling the crossovers. Analyzing the charge-coupled crossover schematics it seems to me if you remove the battery voltage the crossover reverts to the usual passive unit so an A/B listening comparison should be very easy just by putting a switch in the battery line. Has anyone tried this?

[4313B]

You can build your cc networks and leave the batteries out for a few weeks while you get accustomed to how the new networks sound. Then install the batteries.

Or you can just compare two sets of loudspeakers like a few guys did with their 18Ti's, 120Ti's, and 250Ti's.

[1audiohack]

Wow this subject has been a lot of fun!

I have ordered the components to build a pair identical to the 3106, the "B" pair, and a "C"pair, charge coupled. Then I will run them against the "A" pair.

The reason for the "B" pair is for control, it would not be objective to test against my old 3106's with their old caps and all. I will also exlude the L-pad with fixed value resistors. I will of course A B C test.

Its probable that small improvements would make themselves more evident in the higher order more complex networks, this is just where I chose to begin this journey.

I just bought a new TEF 25 PRO kit with all the extras for component testing. It is even supposed to be able to measure and display Heyser Spiral plots on capacitors, and inductors. A lot to learn here to get good data! $3500.00 in red pills! Its never gonna be the same from now on.:D

So I hope to be able to measure and post the results, but in the end, its all what ya hear.

Thanks for all the input. Keep up the fight, ha ha.:barf:

[Domino]

Well I'm almost ready to make the plunge to Charge-coupled for my L300's. You guys really think it makes all the difference huh??

[1audiohack]

I really don't know,,, yet. I doubt it makes ALL the difference, however performance is why I love JBL.

They really are well built hotrods, hence the romance most of us of feel toward them.

Keeping them running, and improving if and what we can is the never ending adventure.:)

[4313B]

You guys really think it makes all the difference huh??JBL has used this charge-coupled technology in many of their TOTL loudspeakers for years now. We have the option to apply this technology to our older loudspeaker systems. It makes for a very nice improvement that many people enjoy.

Back when JBL started using bypass capacitors in many of their systems we applied that technology to our older JBL's and that made for a very nice improvement.

[Ian Mackenzie]

I have a pair of L300's that I'm considering charge-coupling the crossovers. Analyzing the charge-coupled crossover schematics it seems to me if you remove the battery voltage the crossover reverts to the usual passive unit so an A/B listening comparison should be very easy just by putting a switch in the battery line. Has anyone tried this?


Domino,

Unfortunately it not that simple. The capacitors will hold their charge and the effect on the dieletric will rermain for a period of time. The same holds for connection of the battery. Allow several days for the effect of the battery.There is information somewhere in the library on "how" it works.