whats cool for a modest blh horn that is smooth on cello?

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Hi Ron - - Imight be able to get cutter to do RCA-Fan's horn (?) - if he has time - its the simplest bigger horn - if not might have to go BIB -- seems like BIB would make 1/2 octave tradeoff going lower but losing upper bass . Are BIB too rough (and weak) for cello and bass viola? Best, Freddy
 
thank you very much Bob

Best, Freddy

btw here's Bill's 2.5M horn
gi.mpl
 
BIB too rough (and weak) for cello and bass viola?

My first thought on BIBs was the wave reflection. If the mouth was angled at 45 degrees then this would be eliminated and you would have a smoother response. A curve would only be necessary if the aspect ratio needed correction. Outside of that its a primary TL action with a conical expansion which produces less distortion. IMHO the actions would still need to be balanced.

Add a CC and you have something worth building, it may be tall but still occupies an average size footprint.
And i seriously doubt that a BIB could be considered "weak".
ron
 
You;re going to need a larger driver for sure, I think you will be disappointed with anything less than a 6 inch with decent excursion or an 8 inch.

A quote that make me decide to build Singular cabinets was talking about the cello: A person built some with baltic birch and AER Mk1 and a cellist friend of theirs was quite taken with them. She loved the realism of the sound.

These speakers need to be placed just right in the room , they need corner loading.

Negative points:
Afterward many people tell me there are plenty of better designs out there.
no-one knows who is the genuine AER any more.
Huge cabinets,
very small sweet spot.
 
freddi said:
any faves for drivers and cabinets?

Greets!

Hmm, ignoring overtones and sub-harmonics we need to effortlessly reproduce 65.41 - 987.77 Hz to go ~'live', so it takes a couple of HE 15" drivers/channel to do them justice at low linear distortion in a typical alignment IMO and a rule-of-thumb is that a BLH has a 4:1 displacement gain ratio, ergo a 11 - 12" frame driver is required since we need a ~18" effective diameter single driver, hence some form of two way is what I'd be looking at, though as always YMMV.

GM
 
hi GM - -I don't think the original Karlson with good 15" coaxial is too shabby- the coax is concentric in nature and doesn't spatally disconnect -- I've double 15" JBL bins and maybe 3/4 ton of various funky horns plus meandered a tiny bit with FR -- I'm trying to find the FR-er's "religious experience" but not blessed yet -nothing works right - guess I could try putting Unity on top of JBL - might bring vertical disconnect

Freddy
 
Greets!

Well, as you know, your experience is a bit different than mine, but for the others I got my impressions at a young enough age to hear subtleties all the way up, though not with as a fine a duplex as the 604s, so as always YMMV. Still, my understanding of how it works combined with your numerous and varied measurements makes me want to consider it only for use below 300 - 500 Hz max, but if it has the right driver to give at least +6 dB from 65 Hz ~flat in-room, then it's probably adequate, though being a relatively compact multi-stage BP I can't imagine it sounding as open/effortless as a properly sized BIB.

As for audio 'religious experiences', all your various postings imply that you're like me in that it takes plenty of dynamic headroom to 'move' you, so I imagine you'll always be disappointed with FR drivers unless you BW limit a Lowther DX4 (or better) to its optimum BW and fill in the top/bottom as required, all preferably at least WG loaded enough to provide a fairly wide 'sweet spot'.

WRT the Unity, I was mighty impressed with the original two way XO'd at 300 Hz, but after auditioning the three way XO'd much lower, all I can dream about is a four way XO'd to a true sub system. ;) Anyway, try the Unity/JBL combo digitally aligned as low as you can, it might be plenty good enough.

GM
 
guess oughta pickup a Behringer xover (oh - got analog) - - pretty sure RCA-Fan put some abled thinking into his 8" k(or Fulmer)-slot blh and its response plot seemed to indicate better power in cello region than 208blh (not the little bk20) - heres a note on hit and RCA-Fan horn - do you think its a better compromise than bib? - should I get away from FR before going broke? - at least most common FR is cheaper than exotic capacitors :^)

what is a proper BIB to give effortless sound??????? --I don't think K15 works horribly hard

Freddy

graph
http://gallery.audioasylum.com/cgi/gi.mpl?u=21168&f=RCAFANVS.jpg

note
http://www.audioasylum.com/cgi/t.mpl?f=hug&m=125662
 
I'm pretty sure he did too and the response you've posted indicates it's a better overall performer, but while it may perform fine for many folks hooked on single driver systems, I seriously doubt it will work well enough at higher SPLs to please me and I'm betting you either.

WRT accentuated mid-bass 'slam' I imagine these two will best many BIBs, but the larger BIBs are truly wide BW down into the teens in some cases and fairly dynamic in its optimum BW in a typical room, so it really depends on what your performance goals/trade-offs are.

Well, I've enjoyed playing with FR drivers and having designed/built many systems for others with them they certainly have their place in many HIFI or even HT apps, but when it's time to go ~'live' we need all the efficiency/clarity we can afford, so all things considered I don't understand why you're still 'chasing your tail' WRT finding a FR solution, especially with relatively cheap drivers. Olson came pretty close with his large corner loaded BLH studio monitor, though hardly a cheap effort and I don't see anyone topping it with current technology.

By 'proper', I mean one with plenty of net Vb based on the driver's specs, corner loaded and long/tall enough to load the ceiling some.

?! A totally unexpected observation from you WRT the K's loading. The driver may look like it's not working hard since it's not moving much, but the cab's impressive acoustic loading on both the front and back of the driver has it in a strangle hold same as a BR near/at Fb or a compression horn in its pass-band, increasing its output per watt (acoustic efficiency) at the expense of some thermal power compression that the BIB won't cause due to its much greater acoustic mass. The trade-off for all the BIB's extra gain BW of course is increased horn ripple distortion once the driver goes audibly non-linear when pushed beyond Xmax if there's not enough room gain to compensate.

GM
 
which drivers have sufficient linearity and displacement for these BIB and how large should the pipe be? if power handling drops down to 1/4 or so of a watt in the midbass then I'd guess there would be limited dynamics (?) - -Danley uses drivers with "some"displacement ability in his tapped horns. the 6" and 8" BIB I modeled dropped below one watt midbass power handling relative to 1-1.5mm excursion. I like the idea of one driver doing it "all" but don't trust my old nemesis the gurgleman.

I'm leery of pipehorn "droning" like some reflex, pipe and t-lines when excited by bowed bass viola or cello so don't know what something might sound like from its hypothetical (or real) frequency response graph.

re:thermal -my ears compress pretty well -haha

back to "modest", making a BIB the size of RCA-Fan's blh (~7.5 cubic foot external box) will weaken power handling in the cello region (other than pluck) for exchange of more resonance around lower C note -which is the best tradeoff? - is it genre dependent?

I might try RCA-Fan's hitbox w. M151 and cheap round waveguide

best,
Freddy
 
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