3 way crossover help

[tinitus]

Going powered is the best ( and often cheaper ) option when talking about crossover frequencies below 200/120Hz

might be worth to consider
if you have very good drivers it could be a good idea, absolutely
and you dont have to do it all at once
start with cheap 3way xo
in the meantime you can still fool around with hybrid active/passive xo
tweeter amp may not need to be very fancy or expencive, etc etc

and active speaker technology might be something you will have to learn anyway

 

[balerit]

absolutely, and for more than just testing
just remember, you can always try and make a capacitor bigger by adding more in paralel
but you cannot make a big one smaller

bipolars comes in different quality too
roughed foil is used for higher capacity
for quality crossover best use 'smooth foil' caps
some of them might even outperform a film cap
but not always cheap either

edit, migt look at Mundorf E-cap AC (bipolar)


both smooth and rough foils

Or you can scale the values.

 

[bcmbob]

Hello to all.

I'm in the process of upgrading the crossovers for the Sunflower speakers. I'm getting a bit of harshness or synth-like quality close to the mid to tweeter XO point. It is the range where big band trumpet section sounds are most prominent. Vocals and small groups don't produce the effect - but I listen to a lot of big band music. Everything else is perfect to my ears including balance, stage and ambiance.

I have new Mundorf MResist MOX 10W resistors and a selection of Audyn caps ready to go. My question here is about the non-polarized C4, C6 and C7. Can anyone tell me how significant those will be to improving the sound, and give a suggestion of what to use.

This is my first pass at the upgrade and I have retained the original values. I am open to adjusting those values if I don't get the results I'm after.

 

[wintermute]

Hi Bob, My experience with Notch filters, (C5 68uF) being part of a notch on the mid, is that electrolytic caps in this position do not work as well as film caps.

I made a notch filter using an electrolytic, it had two problems. Firstly it did not cut as much as what the sim predicted, and secondly it subjectively sounded like it was adding distortion. I didn't do any distortion measurements at the time so can't say with certainty that it did add to the distortion, but that was my perception.

Now what is tricky with your circuit, is whether or not the value of the cap chosen works correctly with an electrolytic, but may give a different result with a film cap in that place.

the other thing to consider with the other electros is that electro's have higher esr than film caps (epecially the smaller value ones) This can work to your advantage so straight swaps of films for electrolytic's *may* have unexpected side effects. In the case of c6 I would not think there should be an issue as it already has a resistor in series with it.

C7 may or may not cause a problem, what you may get is some peaking due to resonance with the coil. addition of a low value resistor (say 1/2 ohm) in series would probably tame it *if* there were a problem (I'd have to check the typical ESR of a 100uF electro, it may be more or less than 1/2 an ohm). But I'd not bother to start with unless there seems to be a problem.

C4 I can't see being a problem if changed to a film cap. from sim's I have done it has been shunt caps that seem to cause peaking.

As for what to try, I used Axon film caps in my crossover and have been happy with them. I've not tried anything boutique. Partsconnexion sells them at a very good price. Certainly they should be a step up from electrolytics (caveates mentioned above aside)!

Tony.