A 2-way tower with Vifa woofer and Fostex FE103E...

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#62
So either the cap or inductor determines the XO point?

Right now as you know, I have the Solen 51uF cap across the woofer. Since we already know the value of that cap, I think it would be a good idea to get a couple of new inductors of known value to put across the Fostex drivers. It's just a matter of knowing which value to go with.

I have no clue what the actual XO point of these speakers are, but would like to have them somewhere between the agreed 500-800Hz, which hopefully can be achieved using the existing 51uF caps.

Do you have any idea of where the XO point is on these guys? And do you know of a good XO point to aim for?

I have to say, they sound just about prefect in all areas except in the lower vocals (lower midrange I guess), they seem to be just a tad bit light, but doesn't seem to be all the time. Also, the upper most extreme treble sometimes seems a tad bit disconnected from the rest of the sound, but again, not all the time. Maybe it has to do the way some of the music was mastered.


And as an update, I went out to RatShack first thing this morning in search for some resistors. The only useful ones they had there were 10 ohm/10 watt wirewounds. I was afraid they were going to cut the little 4-inchers back too much, but they turned out to be just about perfect.
 
#63
chops said:
I have no clue what the actual XO point of these speakers are, but would like to have them somewhere between the agreed 500-800Hz, which hopefully can be achieved using the existing 51uF caps.

Do you have any idea of where the XO point is on these guys? And do you know of a good XO point to aim for?

I have to say, they sound just about prefect in all areas except in the lower vocals (lower midrange I guess), they seem to be just a tad bit light, but doesn't seem to be all the time. Also, the upper most extreme treble sometimes seems a tad bit disconnected from the rest of the sound, but again, not all the time. Maybe it has to do the way some of the music was mastered.
Click to expand...

After some more listening, especially now at much higher volume levels, they are sounding much much better. I don't know if it's from the drivers "re-breaking in" from sitting for over 2 years, or the new 10 ohm resistors settling in or what, but the speakers are sounding a lot better. Even at lower levels they sound great. They seemed to have filled out in the lower vocals and the extreme top end is smoothed out and "reconnected".

I think I'll leave the XO point where it is for now as it sounds pretty darn good. Extremely good! They are every bit as good as my NHT 2.9's, if not a little better! Bass is just as deep, detailed and punchy, but more dynamic, and all from a single 8" driver!

And what takes a 6.5", 4" and 1" driver to do in the NHT's in roughly the same frequency range (320Hz - 20+kHz), the Fostex FE103E is doing a better job, and it's just a single 4" driver. The treble from the 103 is better mainly because it's a lot more tame than the NHT, yet it's still every bit as extended from what I can hear. Imaging, depth and staging rivals the NHT's by a good margin in my room.
 
#64
I think the crossover point is 500Hz. The R value of 10ohms is the good value. But I think you could have better result if you add an inductor on the woofer, second order. Not too complicated to test 😉

The couple 5,3mH gives 500Hz and the couple 3,1mH is 700Hz. I suppose 3mH is the second inductor from the Dayton CI board.

Have fun
 

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#65
jerome69 said:
I think the crossover point is 500Hz. The R value of 10ohms is the good value. But I think you could have better result if you add an inductor on the woofer, second order. Not too complicated to test 😉

The couple 5,3mH gives 500Hz and the couple 3,1mH is 700Hz. I suppose 3mH is the second inductor from the Dayton CI board.

Have fun
Click to expand...

Where did you come up with those values for the Dayton inductors? I looked all over the place for them and couldn't find anything, even on Dayton's site.
 
#69
Sorry my writing is a little confused. I wanted to write 5mH/3mH instead 5,3mH The couple 3mH/1mH rise the crossover frequency to 700Hz.

The basic circuit 5.1mH in series with 51uF crosses at 500Hz. Add the inductor (2.7mH) don't change the crossover frequency, but improve the phase response.

I can say that because I have measurements of loudspeakers closed to the P21 and the FE103.

The inductor and the capacitor work together. It's a series crossover.
 
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#70
jerome69 said:
Sorry my writing is a little confused. I wanted to write 5mH/3mH instead 5,3mH The couple 3mH/1mH rise the crossover frequency to 700Hz.

The basic circuit 5.1mH in series with 51uF crosses at 500Hz. Add the inductor (2.7mH) don't change the crossover frequency, but improve the phase response.

I can say that because I have measurements of loudspeakers closed to the P21 and the FE103.

The inductor and the capacitor work together. It's a series crossover.
Click to expand...

So put the other iron-core inductor inline with the Vifa like I did the resistor on the Fostex? Just to the positive terminal of the woofer?
 
#73
I know it's been a bit more than a few, but hey, when dinner is ready... LOL

Anyway, I added the inductors to the woofers with great success. The overall sound is fuller and more natural, and with even more dimension than before. I find it very fascinating and satisfying that these speakers are sounding this good with such a hodge-podge of crossover components, but it works great!

I just wish Vifa still made these drivers as they are excellent performers and were fairly inexpensive. Detail, depth, control, extended range into the midbass, it's all there. Likewise with the Fostex drivers except on the opposite end of the spectrum.

For a pair of speakers that probably cost about a max of $300 for the raw parts including the wood, are giving my NHT 2.9's a very serious run for their money in every respect, and they cost $2500 when new! 😱
 
#75
Well I'm at work today but my girlfriend has my system playing, so all the drivers are being worked in a little more, along with the crossover components. The other night, I also lengthened the ports to the proper tuning freq of 28Hz instead of the original 40Hz. I haven't heard them yet tuned this low, so it should be interesting when I get home tonight and have a listen.
 
#77
So last night when I got home, I decided to try putting that 3 ohm resistor in along with the current 10 ohm resisitor on the Fostex, only when I did, it made things sound terrible. The FE103E seems to be louder again and rather nazzely.

Did I not connect the second resistor correctly? I have it parelled with the other resistor. Should they be wired in series with each other to make 13 ohms effectively?
 
#79
Well I rewired the resistors to the way they should be, resulting in a 13 ohm load, however the little Fostex drivers don't seem to sound as good as they did with just the 10 ohm resistor. I don't detect any reduction in output at all really, and they seem to half a slight bit of "honk" to them.

I'm thinking of ordering a pair of 15 ohm and possibly 20 ohm resistors to see if that helps. Maybe these little guys don't like having more than one resistor on them at a time or something.

I'm not screwing up the crossover at all having these two resistors in the setup, am I? And no, I don't mean actually causing harm, just throwing the crossover off or something...
 
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