Where to save money on crossover components

[waltona]

Hi All

I'm looking at building Troel's Amish speaker (I already have the driverrs) but his crossover looks like it will bankrupt me!

http://home1.stofanet.dk/troels.grav..._series_v2.GIF

Where could I use cheaper components to bring the crossover cost to a more WAF level? Or should I just start saving and use decent spec components troughout?

Anybody got any cheaper designs using the 8545 and 9500 drivers?

Cheers

Al

[Magura]

This xo can be made with good quality components for someting like 30£ per channel, is that too expensive?

Magura

[Jennice]

Hey,

I'm in DK too... I could need suggestions on fair-priced X-over component sources, although i'm thinking of DK / scandinavian suppliers.

Jennice

[waltona]

Thanks for the replies. I suppose £30 per speaker is not over the top but any money saved would be helpful. E.g. Do all caps have to be polyprops or can some be an electro and poly in parallel? Can I substitute large air cores with iron cored inductors with similar DCRs? If I'm buying a few better quality caps, where should they go? etc, etc.

I'm looking at sourcing the components from http://www.lautsprecher-shop.de/ .

They seem pretty reasonable on quality and cost (apart from 17 euro delivery to UK). Certainly much cheaper than UK suppliers.

Al

[rabbitz]

My advise is to stick with the metallised polypropylene caps and air core inductors.... your speakers will sound better and will sound that way for longer. Keep away from electros but NP can be used in stuff like zobels.

[Jay]

You can use ferrite-cored inductor in 4.7mH. Not only because it is the biggest, but as a compensation circuit it works on narrow frequency range.

0.15 and 0.22 do not need to be high end. Often when I build a crossover (series), the prototype is using cheap (smaller value) inductor and when finished I tried to replace with quality one (I measured the inductance) but the cheap inductor sounded better. May be because of different DCR I don't know. But if so, then lower DCR doesn't mean better, and may be keeping the DCR as the original design is more important.

Worse cap (electrolytic) may be used in the compensation circuit (11.5uF). Quality ones might go for the 6.8uF ones.

Also, I often found that electrolityc (axial NP) while not as detail as Solen cap, they are easier on ears. And, they are not as critical as in parallel crossover. Last night I tried to use Black Gate N (electrolytic) in parallel crossover, and they were absolutely worse than Solen MKP, but I believe there's a possibility they turn out to be better since normally it takes very long time for such Black Gate to burn-in.

From others' advices/comments below, I read a message saying that when you use high quality expensive drivers like SS, why bother trying to save very little amount of money for the crossover parts???

But let me tell you something important about crossover. Correct crossover (hence correct values) is a LOT LOT more important than quality parts. The good news is series crossovers are very very tolerable. But still you better use exactly the same values (hence unwinding some inductors?) IMO.

[jomor]

I m not sure about using a cored inductor, in such case an accurate measuring equipment is required to make sure the desired value is maintained in the frequency of interest (where the notch is tuned), since the inductance of core inductors vary with frequency. Most inductor values are measured at 1Khz so if the notch is close to 1Khz you can trust the nominal value of the cored inductor you re going to buy.

I couldn't agree more with the rest though, a slight change in a component (DCR of an inductor for example) will not affect the magnitude of frequency response noticably, but it will mess up the phase response very much. Use exactly the suggested
by the designer values. Besides, cutting cost on crossover while using scanspeak drivers is really a pity.

[Magura]

Originally posted by Jennice
Hey,

I'm in DK too... I could need suggestions on fair-priced X-over component sources, although i'm thinking of DK / scandinavian suppliers.

Jennice

Originally posted by waltona


I'm looking at sourcing the components from http://www.lautsprecher-shop.de/ .

They seem pretty reasonable on quality and cost (apart from 17 euro delivery to UK). Certainly much cheaper than UK suppliers.

Al

You should look at suppliers like Elfa and other industrial suppliers, any company with a name that suggests audio or the like is a very expensive solution.

for caps you could choose Rifa PHE426, those are very high quality and quite cheap. I personally don't use anything but air core inductors, they don't cost much for xo purposes.


Magura

[Jennice]

I personally don't use anything but air core inductors, they don't cost much for xo purposes.

Except that I need a 12.6 mH !!!

Jennice

[Magura]

That's still fairly small,. I have recently made a couple of 80mH for my Zen V7 project, now that is close to the practical limit They ended up around 20kg. a piece for a double 80mH 2.4R.

12mh is like 2kg or so, no big deal and relatively cheap.

Magura