Canned Crossover Design - What Next?

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16ohm, yes wasn't sure how do that...as shown in 1st pic
or make up mini xo board and separate out the tweeter?
 

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Can't believe I missed the second part of that link/page aye crumba

Have these parts and this uses the same 8.2 series cap, were you suggestion to try this xo for tweeters?




I assume we are talking about Troels' two versions of the Vifa PL14WJ.
Vifa PL14WJ-
He seems to just scrape it on the d'Appolito version on levels and impedance by lowering resistance in the treble filter.

Since you re struggling with tweeter level here on a 4R parallel wired d'Appolito, why not try the easier series wired 16R version? It's altogether easier to implement anyway, and I like what it does. Very easy amplifier load. :)
 

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+1 Avoiding poor/dirty connections is more important.

With the drivers this way, for a given drive voltage the current for a each driver will be halved. The voltage across each driver will also be halved so the power is quartered, or -6dB.
 
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Aye that much; might be looking for tweeter after all (that is less efficient).

The 88db Dayon with the screen/grill had some good reviews.


+1 Avoiding poor/dirty connections is more important.

With the drivers this way, for a given drive voltage the current for a each driver will be halved. The voltage across each driver will also be halved so the power is quartered, or -6dB.
 

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me too :) Doug the main concern with the gauge of the coil is DC resistance. Look at what that coil is in series with..... a six ohm resistor. You don't need to minimize the DCR of the coil just to show a big resistance in series with it again :)

I probably should do a sim to make sure what I am saying is actually factual (because it is L C R rather than L R C) but I think that if you had a high DCR coil as long as you reduce the R by the an appropriate ammount the total effect will remain the same.

OK I did a sim, L1 is 0.2 ohms DCR, L2 is 1 ohms DCR L3 is 1 ohms DCR with R5 reduced by 0.8 ohms to compensate for the extra resistance in the coil.

So as you can see, provided the overall resistance remains the same it doesn't really matter if it is in the coil or in the resistor :)

There may be some practical limits that I am unaware of, but using a lighter gauge wire in this instance should save money and space with no real downside.

Tony.
 

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A tad OT, but... I once wound a coil for my 1st TQWT which was to notch out a breakup peak using only 1 extra component. Through sims in Boxsim I found I needed 48uH at a DCR between 0.5 and 1 Ohm. I wound it using 22ga on a M12 machine bolt, rough n ready. Took an LCR meter to it and tuned it to 48uH. DCR came out at 0.42 Ohm. The rest of the R was made up with a 0.47 Ohm resistor, but I took it out in the end, the coil was just right as is. I have more trouble with RC shunt resistances being a bit high.
 
Okay sorry for the delay...
So working very nice - best so far.

A MTM with 16ohm woofer connection and the Vifa original xo (didn't want to change to many things at once)

The bass is about the same (still plenty) the middle is nice and natural, better than the high mounting idea.

The treble is probably to high; hovering around either too low or to high.

Delightful sound though :spin: Thanks guys!!

***
16ohm load (I guess) now I can bridge two amps and not worry.
 

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I think this is the last go :hypno2: but seems like always getting better.

Changed out tweeter The Madisound Speaker Store

Combined xo from the SF 8"/combination (which is pretty basic) to existing. Tried it without the L pad first - too much high, so put that back in: R1 2.2, R2 22, -3db, which also means could use a 88db tweeter (like the Dayton).

Would build this again, delightful sounding pair of speakers.
 

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Success with the new tweeter experiment; changed R22 a few times, ended up replacing R22 with 2 - 4.7ohm (9.4ohm).
This tweeter just sounds better, a much better blend - overall.

The 16ohm hookup seems to make the amplifier work harder; not complaining, the 6.5s have a monster stomping around sound to them. (maybe the side ports work...I don't really know).

Wondering what to do with all these extra boxes for the 8" version :rolleyes:
 

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