The shippment of madisound is really expensive.
Can I use one of these options:
3x Mundorf Ecap 330uF 63V
or
3x Mundorf Ecap 330uF 63V
1x Mundorf Ecap 10uF 100V
?
Can I use one of these options:
3x Mundorf Ecap 330uF 63V
or
3x Mundorf Ecap 330uF 63V
1x Mundorf Ecap 10uF 100V
?
I assume the 1,000 uF cap is in your woofer? If so, you are starting with the wrong parts. 🙂
In any event, 1 x 10uF cap won't possibly work. 🙂 Did you mean 1x Mundorf Ecap 1000uF ? that would work. 🙂
In order:
1. Change the resistors to Mills non-inductive wirewound. Depending on the total wattage, you may even be able to cut the resistor count down to 1 instead of 2.
2. Change the film cap to Mundorf MKP
3. Upgrade the solid core inductor to either a nice Jentzen air core or P-Core.
4. Upgrade the 1,000uF cap to Mundorf Ecap (3 x 330uF) they're pretty cheap.
You may need an LC meter, I've seen them around cheaply, around $30. Also built into Dauton Audio's DATS.
In any event, 1 x 10uF cap won't possibly work. 🙂 Did you mean 1x Mundorf Ecap 1000uF ? that would work. 🙂
In order:
1. Change the resistors to Mills non-inductive wirewound. Depending on the total wattage, you may even be able to cut the resistor count down to 1 instead of 2.
2. Change the film cap to Mundorf MKP
3. Upgrade the solid core inductor to either a nice Jentzen air core or P-Core.
4. Upgrade the 1,000uF cap to Mundorf Ecap (3 x 330uF) they're pretty cheap.
You may need an LC meter, I've seen them around cheaply, around $30. Also built into Dauton Audio's DATS.
If you do decide to upgrade the coils, please make sure the new coils have a DCR that is close to the factory coils, or you can have a negative effect on transfer function and driver levels.
Or to limit LF to mid-woofers, and let it go to woofer?
I still don't know how this 2.5 way crossover works.
The 1x10uF cap is to make the 1000uF.
3x330+10=1000uF.
I forgot to mention that I already made this, except the inductors.
Thanks
If he uses equivalent coils, how is he going to hear a difference? 😀😀
You are right, of course, but I would say the bigger danger is the woofer levels changing. Without appropriate measurements it's going to be hard to tell what such a change might do, or if he'd be pleased with the result.
Best,
Erik
IMHO there is nothing to upgrade.
The resistors and coils don't degrade, so no need to replace.
The film caps don't degrade, so again no need to replace.
The only thing that degrades over time is an electrolytic cap, and this need to be replaced after some years (10?), because the value has changed. I don't think you need to replace it now, but if you want change it, do only with a similar one (bipolar electrolytic), because of the ESR, whose value Kef surely counted in the crossover implementation.
Ralf
3x 330uF + 1x 10uF are technically equal to a single 1000uF cap. However leaving out the 1x10uF cap makes a difference of 1%, negligible considering the fact that it is hard to buy caps with less than 5% tolerance. The single 1000uF cap is at least anywhere in the 950-1050 uF range.
The resistors and coils don't degrade, so no need to replace.
The film caps don't degrade, so again no need to replace.
The only thing that degrades over time is an electrolytic cap, and this need to be replaced after some years (10?), because the value has changed. I don't think you need to replace it now, but if you want change it, do only with a similar one (bipolar electrolytic), because of the ESR, whose value Kef surely counted in the crossover implementation.
Ralf
3x 330uF + 1x 10uF are technically equal to a single 1000uF cap. However leaving out the 1x10uF cap makes a difference of 1%, negligible considering the fact that it is hard to buy caps with less than 5% tolerance. The single 1000uF cap is at least anywhere in the 950-1050 uF range.
Ralf is in another camp. Here's what I would say. Do the resistor and tweeter cap mods. If you can't hear any positive difference, stop. 🙂
Best,
Erik
Best,
Erik
2.5 Way?
Apologies for the thread resurrection, but I'm curious, given that Kef state this is a first order 2.5 way crossover at 2.5KHz, what is the 1000uF capacitor doing? Where is it in the circuit? Anyone actually know? Opinions are useful of course. I remember that Kef used to place an all pass capacitor in certain crossovers, (could have been in the smaller designs, I don't remember, it's from the 70s or 80s) to enhance the bass (as counter intuitive as that sounds!) It's just that 1000uF seems too much for anything else here. 😕
Apologies for the thread resurrection, but I'm curious, given that Kef state this is a first order 2.5 way crossover at 2.5KHz, what is the 1000uF capacitor doing? Where is it in the circuit? Anyone actually know? Opinions are useful of course. I remember that Kef used to place an all pass capacitor in certain crossovers, (could have been in the smaller designs, I don't remember, it's from the 70s or 80s) to enhance the bass (as counter intuitive as that sounds!) It's just that 1000uF seems too much for anything else here. 😕
The woofer should be rolling off much lower (the Q900 woofer rolls off above 120Hz - KEF Q900 loudspeaker Measurements | Stereophile.com)
Does anyone know the same for Q500, Q700 ?
Does anyone know the same for Q500, Q700 ?
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