Crossover advise for my L112's PLEASE!!!!!!!!

[jblman]

51419

I notice that C1 and C3 caps are listed as mylar is C2 a mylar or poly?
Also c1a, c2a, c3a in my speakers are the .068uf what benefit do I get from changing them to .01uf as shown in the schematic as a performance improvement? :D
First off I don't want to change the speaker to much just give them a complete refresh.
Any advise would be greatly appreciated!!!!!
Thanks!!!!

[Robh3606]

Also c1a, c2a, c3a in my speakers are the .068uf what benefit do I get from changing them to .01uf as shown in the schematic as a performance improvement? :D


For all intents and purposes they are the same value in this application. If you do re-cap the crossover changing to .01 won't hurt. C2 is probably Mylar and well and if you have the crossovers it should look the same Yellow??

Rob:)

[jblman]

51420
Hey Rob,
Thanks for the quick reply!
Here's a good picture of the crossover I shot the other day.
So here's the current values upper right 13.5uf which you can see, lower left 6uf and to the right of that 3uf.
Sand casts are 2.5ohm, 20ohm and 50 ohm @ 10w
So you tell me?
And what change in sound would I get from the .068uf to the .01uf?

[Robh3606]

So you tell me?
And what change in sound would I get from the .068uf to the .01uf?

I wouldn't expect any audible change. I am not going to get into the audible differences between different capacitors. There are tons of stuff and web pages on the internet about the subject. From my point of view any audible differences from switching capacitor brands would be minor and something you can experiment with and see for yourself. The cheapest bang for your buck and one of the best options would be to Charge Couple them using Solens like JBL does in the K2 9800,9900 and Everest. Compared to the cost of the botique caps it's a very inexpensive option.

Rob:)

[jblman]

Ok, so changing from the mylars to a pp isn't going to change the sound that much? I like the sound they already have but would like to just refresh them. That's my whole idea.

[grumpy]

Seriously, listen to Rob. For ~$100: 12 capacitors and 6 resistors later
(includes both speakers), you're done.
No need to reintroduce the bypass caps (.01 or .068 or whatever).

[Eaulive]

Seriously, listen to Rob. For ~$100: 12 capacitors and 6 resistors later
(includes both speakers), you're done.
No need to reintroduce the bypass caps (.01 or .068 or whatever).

You forgot the batteries :D

[rdgrimes]

Ok, so changing from the mylars to a pp isn't going to change the sound that much? I like the sound they already have but would like to just refresh them. That's my whole idea.
IMO, you're more likely to hear a difference from simply replacing old caps with new ones than you are with changing to different type caps. CC is another matter and doesn't really relate to your question but is worth considering.

Don't forget the L-pads, these have a much greater potential of interfering with audio nirvana.

[jblman]

I wouldn't expect any audible change. I am not going to get into the audible differences between different capacitors. There are tons of stuff and web pages on the internet about the subject. From my point of view any audible differences from switching capacitor brands would be minor and something you can experiment with and see for yourself. The cheapest bang for your buck and one of the best options would be to Charge Couple them using Solens like JBL does in the K2 9800,9900 and Everest. Compared to the cost of the botique caps it's a very inexpensive option.

Rob:)

So tell me more I'm kinda new to this so break it down for the newbie! (charge couple)

[Robh3606]

Here you go. Start reading the thread and go to the links. You should be up to speed after that and feel free to ask questions if you are not.

http://www.audioheritage.org/vbulletin/showthread.php?3555-Bypassed-and-Biased-Capacitors

Rob:)

[DavidF]

"...Ok, so changing from the mylars to a pp isn't going to change the sound that much? ...".

The combination mylar/polys as installed is pretty good mix. No need to change anything. As advised elsewhere a good cleaning of the Lpads and the various connections is a good thing to do after 30 years or so.

Still have the urge to tweek? Then it's an open field. You can replace the caps and you may hear a difference. Don't think I would, at least not a OMG difference. Then again, every time I clean and refresh the oil on my cabinet's wood veneer I swear I hear an improvement as I sit back and look at the work I justdid. For a while anyway.

[jblman]

Here you go. Start reading the thread and go to the links. You should be up to speed after that and feel free to ask questions if you are not.

http://www.audioheritage.org/vbulletin/showthread.php?3555-Bypassed-and-Biased-Capacitors

Rob:)

Wow! What was I thinking! This makes sense but I'm going to let it sink in before I start asking questions. So for tonight thanks for the direction! I'll be in touch.

[jblman]

Ah, never mind here come the dumb questions! LOL!
I figured out how to make the 3uf (2 - 6uf caps in series) and the 6uf (2 - 12uf caps in series) but what about the 13.5? Should I just move it up to 15uf instead of moving it down to 12.5uf? Since Solen doesn't make a 27uf cap.
Now, the battery has 3 points to feed in the circuit. But, what do I do with the ground on the battery where does it connect into the circuit? Signal ground?(Binding post)?
And it looks like I can build all of this using the same board correct?

I know, a lot of questions but if I'm going to do this I want to do it the right way. :bouncy:

[4313B]

Since Solen doesn't make a 27uf cap.I buy them fairly regularly - PA2700 or PB2700.

http://www.solen.ca/pdf/solen/fastcap.pdf

Now, the battery has 3 points to feed in the circuit. But, what do I do with the ground on the battery where does it connect into the circuit? Signal ground?(Binding post)?The negative lead of the battery goes to the negative or black input terminal of the network. The positive lead of the battery goes to the array of 3 M ohm resistors and then those resistors each go to the capacitor pairs.


And it looks like I can build all of this using the same board correct?Some people can fit everything on the existing boards. I usually just build new boards.