G'day Dave! It must be 2 am in Brisbane now?
95 dB... hmmm... maybe P10 Dave can comment on that since I haven't got the experience. For pop and rock I still suspect the material more than your gear! As you've rightly stated most of the stuff get's painful at high dB if you're looking for details. One possible solution is bi-amping - I am experimenting with that positive impressions.
BTW, if you don't mind me asking, what are your room dimensions?
It would be nice to guarantee you're wrong about the "limitations" of the Alpair7.3 for your application in this or any enclosure, but only you can be the final arbiter of that.
The Fostex FE126 does have a bit more of a dynamic "jump" factor and forward midrange presentation that I find gives them a subjective impression of being louder than they actually are - a characteristic that some folks find fatiguing ( I don't particularly), but the Alpair is much more refined in lower level details and extends the "3D" soundstage much deeper behind "the back wall".
I've not heard a direct A/B comparison of these 2 drivers in the FH3, but have had enough exposure to them both in many other types to conclude these characteristics are definitely those of the drivers, not the enclosures.
Your separates system would easily accommodate a simple passive line level HP - whichever drivers you decided for FH3, reduction of this LF excursion would contribute significantly to their attainable SPL, as well as improve midrange dynamics and clarity.
I have seen a blog post on Ben's flat-paks which, IIRC, has some ink on assembly. Ben's roughly follow our flat-paks and they are quite easy yo assemble... with patience they should be doable with masking tape & the contents of a bookshelf.
Given the quality of the support gear, A7.3 is a very good bet
Most likely the interaction of the high output impedance of the SET and the ugly impedance curve of the SF
You are going to get a big peak right in the range of where the XO pushes the impedance skyward, right in the ear's most sensitive area, and, as you turn up the wick, right where the equal level curve where you would have that portion of the spectrum dialed back
Any full-range driver will have an impedance curve (both magnitude & phase) that the SET will be MUCH happier with.
Link to the post with the most current planset in post 1 of this thread: http://www.diyaudio.com/forums/full-range/172937-frugel-horn-mk3-builds-build-questions.html
I'm gonna guess yes.
Your SET is something like 18W? Unless you listen at crazy levels, in a really big room i wouldn't worry about getting that kind of efficiency (the FE126 does get close to that thou -- it is the fave of those with 2-6 w SETs). I have 20W and a biggish room (and an amp that likely doesn't overload with quite as much grace as yours) and have no issues with A7/EL70/CHR
When people talk about SETs and efficiency they ignore that the nature of the impedance curve is MUCH more important.
Factoring into this whole thing is the unresolved conundrum that Mark Audio drivers are happier with amps much smaller than "common wisdom" would suggest. I have one customer who was very pleased with the levels he got in his largish room, with CHR70 (1st gen/82 dB 1w/1m) and his 3.5W SE
I have a 3/4-finished pair of FH3's.
I'm in Kenmore Hills. Where are you?
Ok, so I have UL 6bq5's. I think I will take a punt on it. the room is 12 foot wide