Result!
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Love the look of them,would love to try a large sub one day
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This thread needs pictures
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Indoor ones might need a wide-angle lens 
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And videos. With jazz playing through your JBLs - its the only possible way we can experience what you are hearing in-room.
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Oh yes!
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I havenât connected mine yet and realistically am unlikely to ever need more than one. So there could be a JBL 4645c available if you want a chunky sub
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Next installment of silliness here will be eventual conversion of the JBLs to run actively, 4 way.
Currently running 2 way passive and loving the sound but the temptation to faff is hard to resist. Everything is so modular and accessible, it seems rude not to have a play. This is my first foray into anything like this so there may be numptie questions ahead.
I have super tweeters and a crossover on their way. Sub needs eq to give intended response so am thinking something like a Crown XTi would suit and be easy to source. Above that will be the 2x15" that will be running roughly 80Hz to 800Hz with horn tweeter and super tweeter above that. I am not at all sure which way to go for amps on the upper 3 ways. I guess something with some grip on the 2x15" lows and fewer better watts on the highs and highers.
Any input would be welcome.
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Crown XTI sounds sensible.
I have the XLS version on midbass. Good grip and sound at those frequencies.
The variable fans in the Crownâs are great. Essentially never on at hifi volumes / current levels.
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Thanks Steve. What amps are you using in your rig, apart from the XLS?
I had wondered about trying something from Fosi or Temple on the lows but have no experience of chip amps.
Per channel:
TH sub 1 x Eminence Kappa Pro LF2 (8ohm) on a big Cerwin Vega power amp.
Need huge damping factor, that seemed to be the deciding factor on the amps Iâve auditioned.
Mid bass 2 x Eminence Kappa 12As at 4ohm are on the Crown XLS.
High damping factor is required.
Mids are now 2 x 5" Celestion at 16ohm on a 5W EL84 SET. Damping factor seems irrelevant 
HF Vitavox S2s (15ohm) are on 5W EL84 SET. Damping factor irrelevant on a light compression driver diaphragm.
Iâve tried the mids on a 60W T-amp and a Berhringer inuke. Went back to the SET.
I donât have any other amps to try..
The 5" mids donât seem that demanding a load.. mind you they are strictly controlled by Najda DSP going only ~325Hz to 954Hz bandpass, so they are not doing much..
Donât know how much that will translate to your application.
I wouldnât recommend the little SETs for much othan than compression drivers (5" tightly controlled radiators excepted).
For LF and subs check the damping factors.
Added:
With big bass cones you want about >3 fifths the drivers rated power in amp Watts and over 200 - 250 damping factor, to grab them
Otherwise they flop about..
If an amp manufacturer doesnât publish damping factor be suspicious.
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More thanks, thatâs all very interesting. As you say, the two systems are not directly comparable but a lot of your experience will be relevant.
These are my plans so far:
Sub: JBL 4645C which is an 18" driver in a big ported box, 8ohm, power handling 800w (or 1600w, depending how you read the spec). Iâm thinking a Crown of some sort for this.
Lows: JBL 4639 which is 2x 15" in a ported box, 4ohm, ph 600w. 80Hz - 800Hz ish
Highs: JBL 2384 horn with 1.5" drivers, 8ohm, ph 100w. 800Hz - 12kHz ish (intention is to upgrade these drivers at some point in the future)
Highers: JBL 2404H, 8ohm, ph 40w. 12kHz ish and up
I have a Pass Aleph 3 and BAT VK-60 available but am prepared to look further.
Those 2 amps could do well on the upper two channels.
One had a pretty low damping factor good for HF duty.
The bass and sub channels a couple of Crownâs or if you have the XO for the bass you could try a plate amp. They are good value.
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I will use my existing amps for the horn loaded stuff. I spied a Crown XLS1500 on pfm of all places and bought it today, will go well on the 2x15"s. My crossover arrived today too, I need to get my head around how best to set it up. Is there a simple device or software available that would allow measurement for basic adjustments?
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REW is free, great and easy to use, along with a MiniDSP UMIK mic.
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Thatâs great. Sometimes things just fall into place.
Iâve used a Berhringer ECM8000 mic and a cheapie USB input phantom mic amp for some 14 years now, as does @coco, IIRC.
Another 
for REW.
More stable than Holmimpulse.
Holmimpulse was good (free) way back, but REW has taken over.
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I think you mean HolmImpulse rather than HornrespâŚ
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Oh boy, learning curve coming right up!
Yes of course, updated for consistency.
Itâs good with Peer Reviewđ