Choosing wire for crossover capacitor network

[AmCan]

Hi to all,

I am upgrading a pair of vintage Braun L-910s and the capacitors used for the crossover network are just dangling in the box and I need some advice on wiring issues. I have written the capacitor values over this image but I do not know how to draw a proper schematic.

Some of the film Caps I want to use are quite large. I am anticipating needing to change some of these wires and this is where I need some advice please. What kind of wire should I use here, does it matter what gauge it is or what length I need to use between each capacitor. I was thinking that just some or 16 or 18 guage Romex would work real well for bending and staying in place? I plan on using some really large Mundorf MKPs for the Woofer and I don't suspect I can maintain the configuration of the capacitor network as they currently appear. I am going to put in a shelf right underneath to support the large film caps but I will need to increase the wire length between the capacitors to do it. What do I need to consider if I were to do something like this or is a change in wire length like that a nominal change?

Also I would like to change the lamp chord to a passive biwire cable. I am currently using Audioquest Type 4 speaker cable and I would like to put it inside the box. For example, if I were to attach the 2 positive wires from the biwire cable to the current positive feed into the crossover network but then split it into 2, 5-way binding posts so I can passively biwire the speakers at the terminals is this o.k. to do or is it not that simple? Do I need to maintain the 2 terminal configuration or can I change it to 4.

Lastly, I have selected Russian K75-10s for the midrange drivers and tweeter with FT3 teflon bypass caps. I have a 4.7uf K75 and .1uf K4 bypass caps for the bass woofer as well. However, what would be some good resistors to replace the 2 resistors? I am assuming the black 1R0 is a 1W metal film (there is a 1 on it) and the Brown Ceramic resistor is 10W (its brown). I am not as adept at reading resistor values as capacitor values.

Important speaker information
Loudspeakers: A 12-inch subwoofer, three 3-inch midrange systems
and a 1 inch tweeter system (spherical membrane).
Impedance of 8 ohms. Power 60 W
Transition frequencies of the built-in switch 300 and 3000 Hz
Frequency response 20 - 25000 Hz

Thank you for any and all input. This is my first speaker project.
Don't assume I know something

[Cal Weldon]

Originally Posted by AmCan

I was thinking that just some or 16 or 18 guage Romex

That will be fine.

or is a change in wire length like that a nominal change?

Should make a difference.

Also I would like to change the lamp chord to a passive biwire cable.

I think bi-wiring is overated. I don't bother with it.

I am assuming the black 1R0 is a 1W metal film (there is a 1 on it) and the Brown Ceramic resistor is 10W (its brown). I am not as adept at reading resistor values as capacitor values.

1R0 means 1.0 ohm.

I have no problems using the 10 watt ceramic resistors.

[AmCan]

Originally Posted by Cal Weldon

That will be fine.


Should make a difference.

I think bi-wiring is overated. I don't bother with it.

1R0 means 1.0 ohm.

I have no problems using the 10 watt ceramic resistors.

Thanks Carl my fellow countryman for the reply. Just to clarify 3 things.
1. The new wire will make a sonic difference (improvement) but not negatively effect the inductance of the voice coils or cause any other ill to the design of the speaker.
2. Passive bi-wiring is probably a load of bunk but I can do it that way if I want to waste my time.
3.As you can see I can't read resistor values so are you saying I should use a 1.0 ohm & 3.0 ohm 10W ceramic resistor in both places?

[AmCan]

O.K., I think I have come to the conclusion from reading through other sources that significantly increasing the lead length of a capacitor is likely to cause more noise and inductance then what value is gained from using an oversized film cap. I am probably better off using a quality bypass cap with shorter lead lengths then to use a massive film cap to carry the bulk of the capacitance. Greater inductance from the longer lead length would also lower the effective crossover frequency. Is this correct?

[benb]

I'm betting anything Cal was typing too fast or without thinking, and meant to write "Should NOT make a difference" because wire length really shouldn't, unless there's several feet extra between two connections AND you coil it up to remove the slack.

Looking at the project overall, I'm thinking any difference in the sound will likeky be because the new capacitors are slightly different values from the old ones than because of any other change. If you want to test this (we, and especially I, like being all scientific here), replace the wiring first and spend a few minutes/hours/days listening, then replace the caps, and hear what if anything changes between replacing each of these things. Otherwise you could end up attributing any change in sound to the wrong thing.

[AmCan]

Originally Posted by benb

I'm betting anything Cal was typing too fast or without thinking, and meant to write "Should NOT make a difference" because wire length really shouldn't, unless there's several feet extra between two connections AND you coil it up to remove the slack.

Looking at the project overall, I'm thinking any difference in the sound will likeky be because the new capacitors are slightly different values from the old ones than because of any other change. If you want to test this (we, and especially I, like being all scientific here), replace the wiring first and spend a few minutes/hours/days listening, then replace the caps, and hear what if anything changes between replacing each of these things. Otherwise you could end up attributing any change in sound to the wrong thing.

Thanks Benb - that confirms my original assumption that the effect from the change in induction, a couple of mHz, is a nominal change. But of course I should change one component at a time, which is what I have done with my preamp & amp but I don't know why I didn't consider it here. Its more fun that way and you learn what the impact of a change is likely to effect for future reference. Thanks for the reminder on that one.

[Cal Weldon]

Yes, thanks for spotting that. Indeed Cal was typing too quickly. Should not make a difference.

[AmCan]

Back to plan A it is then Cal, but I do appreciate the quick reply. You just made me read more so no harm done I am actually smarter now because of it.
I saw those pictures of all those horns on the driveway. Looks like you are ready for a rock concert! I bet if you could turn the refrigerator into a speaker you would, eh?

[Cal Weldon]

This what I do with refrigerators.

[Cal Weldon]

I have not found a significant difference in the types of caps or resistors. That being said I use polyester caps in the signal path, electrolytic for shunting.
I use perfect layer air coils chokes for signal path and usually air core for shunting unless they are huge and then I will resort to iron core. These are just a preference thing. As usual YMMV and everyone has an opinion.