Something stirs in the Undergrowth

Dedicated to those large boxes at one end of the room
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Ray P
Shed dweller
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Joined: Thu Nov 22, 2007 5:18 pm
Location: Somerset

Re: Something stirs in the Undergrowth

Post by Ray P » Tue May 28, 2019 10:28 pm

IslandPink wrote:
Tue May 28, 2019 9:46 pm
Everyone was surprised what was uncovered !
Maybe you should have had a metal detectorist check you over first, just in case there any hoardes of roman coins or the like secreted within...

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IslandPink
No idea why I do this anymore
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Joined: Tue May 29, 2007 7:01 pm
Location: Denbigh, N.Wales

Re: Something stirs in the Undergrowth

Post by IslandPink » Wed Jun 05, 2019 7:15 pm

Well, new hearing and some re-alignment on OB's from Owston, I forge ahead.
I did some calc for the cap size in the Quasar crossover on Monday . Then I went home and put in approx. 40uF instead of the 56uF. Things got worse. Then I tried 100uF . That was fuller but not quite right .
Then I sat down and carefully looked at the roll-off of the PM6C, the roll-off of the FX120, and did a spice model including the L-pad around the Supravox and the 16R for two FX120 drivers.
Armed with that, tonight, I tried 56uF+20uF - this is much better. I will try 85uF too.

I think I made a wrong turning on this by not re-evaluating the cap size after applying the different attenuation method on the bass driver. I was just hoping the 56uF would be OK.
Now need to decide what to use for 20 or 30uF extra that will fit inside the crossover boxes... hmmm...
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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IslandPink
No idea why I do this anymore
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Joined: Tue May 29, 2007 7:01 pm
Location: Denbigh, N.Wales

Re: Something stirs in the Undergrowth

Post by IslandPink » Fri Jun 14, 2019 8:35 pm

Sounding like 56+30uF is the better of the two. More upper bass tone, and the soundstage is more solid and natural. I have just ordered some 22 & 33uF bipolar Mundorf caps from HFC to see if they're good enough ( they are small enough to fit in the box with the EVO oils ) , otherwise will have to bodge later to enlarge the boxes for more PP/oil.
Anyway, feeling happier with the whole thing now.
"The bass is the king of the instruments - it has no known natural predator" (Wobble)

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