Double bass bin La Scala

[IndyKlipschFan]

This page will help a lot!

http://sunfire.com/pdf/TGA7_manual.pdf

Go to page 15.

If you need the free adobe acrobat reader it is here.. http://www.adobe.com/products/acrobat/readstep2.html

A few pictures and the explanation helps everyone here.

[DrWho]

lol, have you ever measured the response of anything you've built? I've designed plenty of filters and circuits and measured the results. It's really not that complicated. "Mess?" My goodness, it's probably the cleanest, easiest, cheapest approach available.

Let's keep things simple...I've tried your autoformer "solutions" and guess what, the core on the formers saturate very quickly at lower frequencies resulting in a great big high pass filter. Not exactly the kind of device you want on a bass bin (especially the lascala). You also destroy the damping ability of the amp and introduce all sorts of power losses as well. Show me one commerical crossover that puts an autoformer on the bass bin - stupidest idea ever. But by all means, continue spewing crap from your years of experience without verification. [+o(]

your going

to reduce the capacitance by running the xovers in series with the same

load (1/2)....your going to double inductance by running the xovers in

series with the same load

Guess what, in your crazy analogy the load isn't the same. [] In fact, this is exactly what you want to do to the crossover to ensure that the crossover point remains the same! Wow, what an epiphany. No offense, but get your facts straight before you try to lecture someone on filter design. Am I an expert? Heck no, but unlike your rantings I can support things with simulations and measurements. Your craziness about impedance matching is a red-herring.

Have a good afternoon and sorry to everyone for ranting. It gets annoying after a while. In the spirit of PWK, let's seem some measurements Mr. Fritz, of the actual acoustical output of all these speakers you've built with autoformers. And let's see it at various SPL's too, just to bring out the nonlinear effects. But even if it performs well, I could never fathom spending money on a topology that reduces the efficiency of the system...even if you could find a perfect autoformer [^o)]

[IndyKlipschFan]

Mike, and others looking at this....

I have the split La Scala's stacked.. tops inverted.. I ran out of the top section of speaker 1 (with a bananna plug) into the other top speaker 2. So from that 2nd speaker down to built in x over down to the 2nd (other) bass bin. (For those without knowledge of split La Scala's, the low out is in the top horn section you need speaker wire to go from there down to the bass bin.)

This would be the same, I would suppose, as a ( Y ) connector.. to both top ends..then down to their respective bottoms. So parallel to the tops.

Both 8 ohm speakers... so a 4 ohm load. The manual at Sunfire shows ideally not less than 2 ohm load is acceptable. 4 ohms is just fine.

In Series you would add them together.. 8 ohms + 8 ohms..= 16 Ohms..

Parallel like mine 8 Ohms divided by 2 = 4 ohms

My Sunfire handles this just fine.. (I am not at louder at all insane levels here, but I assure you.... sometimes cranked up at quite fun ones in my own HT environment with Concerts or Movies too.)

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[Guest " "]

"Both 8 ohm speakers... so a 4 ohm load. The manual at Sunfire shows ideally not less than 2 ohm load is acceptable. 4 ohms is just fine."

8 ohms is an average which consists of a 3.8 ohm k-33, an 11 ohm k-55, and a 6.8 ohm K-77.

If you Y connect the woofers, your impedance for the LF section drops down to 1.9 ohms.

1.9 ohms is a real test of courage for an SS amp. Doulbe check your amps recomendations. What does time limited mean?

"800 watts RMS per channel into two ohms time- limited basis "

If you damage your amp, send the bill to Dr Who.

[Guest " "]

Dr Who

Here you go.

2hz - 1MHZ

You could probally saturate it with a car battery (DC). But not by plugging it into the wall (60hz)

Same tap stepping as the T2A, 2x, 4x, 8x, 16x, 32x, etc

[Guest " "]

Dr Who

Heres the AF-140

One is good for 150 watts, two in series is good for 300 watts.

I don't know what you used for your tests, but if you take 2 AF-140's and wire them in series, and plug them into a wall AC outlet, they won't saturate. They will sit there slightly warm.

I'ts frequency response is 30hz - 15khz, a LaScala bass bin can not extend down to 30hz.

[mas]

"Both 8 ohm speakers... so a 4 ohm load.

The manual at Sunfire shows ideally not less than 2 ohm load is

acceptable. 4 ohms is just fine."

8 ohms is an average which consists of a 3.8 ohm k-33, an 11 ohm k-55, and a 6.8 ohm K-77.

If you Y connect the woofers, your impedance for the LF section drops down to 1.9 ohms.

1.9 ohms is a real test of courage for an SS amp. Doulbe check your amps recomendations. What does time limited mean?

"800 watts RMS per channel into two ohms time- limited basis "

If you damage your amp, send the bill to Dr Who.

If you want to run ~2 ohm or lower loads, simply get a Crown K1 or K2 series or XTi series amp. They eat 2 ohms for breakfast.

That is precisely one of their strengths!

Heck,

or go with a Crown Macro-Tech amp. I have literally watched one used to

weld in a demonstration (and inadvertently done it as well on another

occasion!) and they don't even shut down! Of course in a dead short

they can draw 30 amps, so you might want to re-wire your circuit for such!

And if these amps can't address your power needs, you need to find another hobby.

Of

course, an active crossover with signal delay would actually address

this issue much better and more completely as well...but why do the job

right when you can find another use for a transformer?

And I

know I shouldn't ask this, but aside from the fact that this can be

done, WHY does anyone want to do this for a small listening room?

[michael hurd]

"8 ohms is an average which consists of a 3.8 ohm k-33, an 11 ohm k-55, and a 6.8 ohm K-77.

If you Y connect the woofers, your impedance for the LF section drops down to 1.9 ohms.

1.9 ohms is a real test of courage for an SS amp. "

Is it?? Jwcullison uses a Mac amp to run dual K-33 on each channel in a vented enclosure, and no problems. As stated, there are various Crown, Qsc, Peavey, Crest and such amps that will drive that no problem....

Don't forget to add about 30% more DC resistance for when the VC starts to heat up.

[jwc]

I AM NO EXPERT

Two K33's in parallel isn't that big of a deal. I took my dbb's to Hope and they were pushed hard by 3 different sets of amps. Dynaco ST-70's, VRD's and some Vintage SS Luxmans. No problem other than the room was bad for acoustics.

I know the published specs for the K33 states just under 4 ohms but I am not sure this is the case "when loaded". I think Albright ought to jump back in an give a tutorial on why he recommended parallel wiring and use "3 ohms" for calculating a low pass filter. Those aren't his exact words but I believe this is what he meant. This is what impedance ALK used on two sets of networks for my dbb's. I push mine on a 4 ohm tap.

I might be wrong with this but could it be that the amp will see 3 ohms with the k33's in parallel and 6 ohms when there is just one K33? Albright...please step in....I'm not a network expert but kust a piddler with em'.

ALK has designed an ESNs for parallel wired K33's if anyone is interested. Or is it "Heresy" to mention his name.

DJK's recommendation to me was to run parallel. He suggested in another thread with someone else doing the same thing with double bass bin LaScalas. I'm quite sure it ws the thread where IndyKlipschFan and Colter first picked up those double La Scalas. Colter was asking the same question as this thread. Indy....you should know what that thread was....just look there.

I wouldn't go by the specs on the back of the speaker.

I would also agree that adjacent-paired La Scalas in a small room.........

I think the idea of a transformer in front of the woofers is interesting. No experience with that. I would like to see more on the subject.

jc

[IndyKlipschFan]

The Sunfire runs cool to the touch..,... Still.

OK, just stating it can be done..and does so with no problem..

I guess with the Sunfire I am lucky too..

I am glad you liked the article on series or parallel though.. It has to help people..

Knowledge helps us all learn.

[Guest " "]

"Is it?? Jwcullison uses a Mac amp to run dual K-33 on each channel in a vented enclosure, and no problems. As stated, there are various Crown, Qsc, Peavey, Crest and such amps that will drive that no problem...."

I have a 45lb brick that used to put out 800 watts before connected to a set of speakers on speaker set A and speaker set B. The manufacture of the speakers claimed 8 ohm compatible. When I turned on the system, I heard a machine gun sound, followed by pop corn noises, then a funny smell. All was quiet. It turns out that the speakers were actually 4 ohms each and I inadvertently put a 2 ohm load on a system not designed for it.

Don't do this blindly...check to make sure your amp can drive these kinds of loads.

No one should should be encouraging this with out the qualifier of checking your amps's spec's.

[mas]

Don't do this blindly...check to make sure your amp can drive these kinds of loads.

No one should should be encouraging this with out the qualifier of checking your amps's spec's.

I'll see you and raise you one more question.

I can certainly understand the "since it's there" rationale, but I would love to have a few questions 'settled'.

Why are we doing this?

Assuming we need the gain, I am assuming that we care about the summed polar and frequency response of he combuined sources (ie: comb filtering and polar lobing anomalies). Especially as we have been told that this will be used in a small room with people listening in close proximity as opposed to in a large room with folks sitting at least '10X the interdriver spacing' units away where any 'merging' of responses begins.

Thus, the desired response characteristics determine the best 'way to go'. Vertical stacking is preferable in all respects unless you simply like the aesthetics of horizontal spacing. See the attached diagram. For vertical stacking, simply turn your monitor or a printout 90 degrees. And no, this arrangement is NOT a line array. And you are going to have even greater destructive room interaction. BTW, different inter-driver spacing intervals simply change the notch frequencies of the comb filtering and the number of lobes (and their Q) at a given frequency. If you sit closer than 10 units you will experience the individual drivers individually and the anomalies without coupling. Coupling is a 'distance' phenomenon.

So, may I suggest that in a small room, all of the various ideas may be moot. But granted, the speaker would definately look cool, and heaven knows that takes precedence over real performance in far too many endeavors in the world today...

Amplifier power to drive low impedance loads is readily available at excellent prices. But yes, if you are intending to use an existing amplifier, you MUST check the specs and a bit more - as specs have a way of, well, not being very reliable. Crowns (K Series, XTi, Macro- and Micro- Tech series will definately drive them and love it),and Lab Gruppen WILL drive it as well. QSC can drive it, although they are not quite as impedance agnostic as the Crowns or Lab Gruppens - but nevertheless excellent amps!

You will of course want to use 'tiptoes', as a few nanometers of movement are critical, especially if you use a passive crossover and ignore the several feet of acoustic origin offset inherent in the driver alignment. Some have suggested I give a 'heads up' when I employ dry humor...so imagine fireworks. The irony is that most will miss the relevance.

For SR use and live sound, this has many uses. In a small room???...I personally would either expand your home theater to X.1 or set up a second dedicated system for music or whatever. But whatever, it is certainly your call.... I must admit that I would not be doing this for a small room. And if I wanted to make a significant change, it would be with an active crossover with signal alignment of the acoustic centers and bi or tri amping.

In any event, before we are buried in umpteen hundred suggestions, it would be nice to define the need, and desired goal. Otherwise, much of what follows, while interesting, is not worth that much.

...watching amazed as the herd of cats runs amuck... []

[DrWho]

Mark....the center to center spacing of stacked lascalas comes to about 2 feet and the LPF on the bass bins is around 400Hz where the wavelength is 2.8 feet. This puts you at a worst case polar response of the 1.5 wavelength and lower charts. Of course, that also assumes an omni-directional Q for both speakers, which certainly isn't the case. I would expect the summed performance to be better than that of the 1 wavelength and lower - which in my opinion really isn't that big of a sacrifice in performance.

The double stacks do take about 10 feet for the sound to gel though...

[mas]

The 'gel-ing' takes ~10 times the inter-driver spacing - so we are talking almost 30 feet in the low end and about 10 feet in the HF.

And you are correct, the polar response of the various drivers is not omni-directional as assumed in the diagrams. More complications. And all of the aspects of the system become more complex and less well behaved.

This is further complicated by the comb filtering and polar anomalies over the range of frequencies, not simply the low end of each bandpass. The high end of each bandpass will not be nearly so well behaved!

Oh, and the best of all of this behavior that we are talking about, is ONLY at precisely one spot on axis, as if you move off from this, the equidistant relationship ceases to exist, and all of the relationships of all of the drivers becomes, well, anything but well behaved.Your best case scenario is only for a very small precise 'spot ' on axis
- and that will not even be realized as the distance for this to occur
will be further away than most rooms are long. Off axis the response
will quickly become a 'mess'.

The fact is, the advantages described are to be realized in a space significantly larger than an average listening room. And even these are not without trade-offs. But as I said before, although their performance will suffer, they will look way cool!

You have a better overall performance by simply using the units individually than you do combined. Especially in a multi-channel stereo or HT configuration.

The only advantage of combining the units is for added gain, and then at the expense of the concomitant polar and comb filtered anomalies. There is no free lunch.

So unless the additional gain is critical, IMO, the additional anomalies more than offset any perceived advantage. More is NOT better in this case. This is a case where the problem you are trying to address is less than the problems introduced via the solution, and as such, the solution is a problem unto itself. In other words, the advantages are more than offset by the problems introduced.

And I still think that the best use of an extra pair of LaScalas are in a nice 2 channel rig in addition to a 5.1 HT setup - especially if you choose to tri-amp the 2 channel configuration with an active crossover with signal alignment with perhaps a Crown K2 and a K1 and D75a or 2 D-75As; 1 each for the MF & HF. And of course a large HGS18 or DD18 Velodyne or IB sub would round out the package very nicely.

[]

[DrWho]

The 'gel-ing' takes ~10 times the inter-driver spacing - so we are talking almost 30 feet in the low end and about 10 feet in the HF.

10x driver spacing according to who and assuming what? I'm just gonna say you're wrong because it's very easy to hear for yourself and I have a feeling you've never actually listened to them in this configuration because you're already skeptical of the concept [] If it "gels better" at 30 feet, then it's not audible and probably swamped by other factors (and this is when listening outside).

[]

This is further complicated by the comb filtering and polar anomalies over the range of frequencies, not simply the low end of each bandpass. The high end of each bandpass will not be nearly so well behaved! Your best case scenario is only for a very small 'spot' - and that will not even be realized as the distance for this to occur will be further away than most rooms are long.

As far as I understand, we've been talking about double bass bins and just a single MF/HF pack. 400Hz is the high end of the bandpass for the stacked bass bins...

You have a better overall performance by simply using the units individually than you do combined. Especially in a multi-channel stereo or HT configuration.

The only advantage of combining the units is for added gain, and then at the expense of the concomitant polar and comb filtered anomalies. There is no free lunch.

Doubling up on the bass bins also doubles up on the total mouth area for the horns. It's essentially the same concept driving the dual driver design of the Jubilee, whereby you get substantial gains in the low frequency response - even if both horns have the same Fc. While I guess this is technically a matter of "gain" - it's a gain in the low frequency extension of the system, which is a big deal when you're talking lascalas. For the sake of stating it - this also comes with changes in the impedance response of the system (for those obsessed with a small region where the minimum occurs).

I agree with the concepts driving the points you're trying to make Mark, but you seem to be making them without considering the specific application. You might as well argue the benefits of making transistors smaller as it pertains to computers. The issues to which you ellude simply aren't that big of a deal - at least I don't think they are. I would be interested in some specific numbers as it pertains to this situation if you really think it matters. Now if you're talking about doubling up on the MF/HF packs, then I would agree completely....one is better than two in that situation, but I don't think that's what anyone here is talking about.

[IndyKlipschFan]

OK so picture 4 La Scala's behind you a surround right.. In the back right corner...and a surround back right.. a surround back left... and a surround left in the left corner...

17 feet from side to side.... This was my original set up.. Till I just could not fool myself anymore.. Something in a side surround needs to be in that seating position 90* to the side to 110* behind you.. (think a few feet from your right angle to where your sitting...) where 0* is straight forward. So your front right and left speakers are 22* - 30* or a little wider if the room permits... The backs surrounds are 135* to 150* again from your seating position.

I am 28 feet from the possible front to back here.... It is shorter with the scrim... Obviously "real" inside space is 24 feet is what it feels like.. too. Still 17 feet side to side...

So with the addition of the 525's.... I had a extra pair of La Scalas.... what's a audio guy to do?? Figure out how to use em of course!! hahahahaha

So again.. I looked at the Sunfire... 2.... 8 ohms speakers.. so a 4 ohm load... I should be fine.

In a worse case scenario.. I can just unplug one pair.... wait the Sunfire has 9.1 setting too, out of the pre amp.. OK, then I would need one more power amp!! wooo hoooo LOL

[mas]

The 'gel-ing' takes ~10 times the

inter-driver spacing - so we are talking almost 30 feet in the low end

and about 10 feet in the HF.

10x driver spacing according to

who and assuming what? I'm just gonna say you're wrong because it's

very easy to hear for yourself and I have a feeling you've never

actually listened to them in this configuration because you're already

skeptical of the concept [] If it "gels better" at 30 feet, then it's

not audible and probably swamped by other factors (and this is when

listening outside).

[]

This is further complicated by the comb filtering and polar anomalies over the range

of frequencies, not simply the low end of each bandpass. The high end

of each bandpass will not be nearly so well behaved! Your best case

scenario is only for a very small 'spot' - and that will not

even be realized as the distance for this to occur will be further away

than most rooms are long.

As far as I understand, we've been

talking about double bass bins and just a single MF/HF pack. 400Hz is

the high end of the bandpass for the stacked bass bins...

You

have a better overall performance by simply using the units

individually than you do combined. Especially in a multi-channel stereo

or HT configuration.

The only advantage of combining the units

is for added gain, and then at the expense of the concomitant polar and

comb filtered anomalies. There is no free lunch.

Doubling

up on the bass bins also doubles up on the total mouth area for the

horns. It's essentially the same concept driving the dual driver design

of the Jubilee, whereby you get substantial gains in the low frequency

response - even if both horns have the same Fc. While I guess this is

technically a matter of "gain" - it's a gain in the low frequency

extension of the system, which is a big deal when you're talking

lascalas. For the sake of stating it - this also comes with changes in

the impedance response of the system (for those obsessed with a small

region where the minimum occurs).

I agree with the concepts

driving the points you're trying to make Mark, but you seem to be

making them without considering the specific application. You might as

well argue the benefits of making transistors smaller as it pertains to

computers. The issues to which you ellude simply aren't that big of a

deal - at least I don't think they are. I would be interested in some

specific numbers as it pertains to this situation if you really think

it matters. Now if you're talking about doubling up on the MF/HF packs,

then I would agree completely....one is better than two in that

situation, but I don't think that's what anyone here is talking about.

I

am speaking specifically to the inverted "double' LaScala - with 2 mid

packs inverted in close proximity as originally suggested by the poster

and modified only as I posted a picture in the last iteration, with

double bass bins and doubled MF and doubled HF in an optimal 'inverted'

configuration. Sort of in a giant MTttTM config.

OK, so we are at

the point of the proverbial hair splitting. And it would take all of

the fun out of things if we chose to actually debate the same thing, so

let's agree not to do that, as that would remove all of the fun of a

debate...and things have gotten a bit dull around here. And I don't

even have a good drummer joke handy.

The multiples of

inter-driver spacing required for the driver response to coalesce and

act as one as opposed to being perceived as separate drivers was

established in 2 complimentary settings. One, at SynAudCon when we did

the original 'invert and splay' testing and proof of performance

measurements documented in the newsletter and subsequently printed in Sound System Engineering

Davis & Patronis, 3rd edition, p.135 figure 6.3 where the polars

are displayed ( I can, upon prodding, probably find the original newsletter article complete with frequency response measurements as well ...and it even includes a picture with me in it of the process - scary huh???(I mean me being in a picture, not the testing!)), as well as in the AES Journal and Keele's study of the

Bessel array** which is, in large part, based upon Mike Lamm's

original voluminous 2" thick stack of TEF measurements which are in my

possession and credited in the study.

Both support the 10X

inter-driver spacing distance for the sources to 'gel' into a single

perceived event, as opposed to being perceived as separate drivers with

all of their glorious comb filtering and polar anomalies. Thus the

message was to either use small drivers in a tight packed configuration

or to sit back a-ways. (Oh, and by the way, in the Bessel, the optimal config

being a 5 unit Bessel, the inter-driver spacing refers to the largest

inter-driver spacing interval, in this case between the centers of the

first and fifth unit - not simply between adjacent units. Another

reason that this tends to be considered more for live SR applications

rather than in a small room - although in systems used primarily for

voice reproduction smaller drivers, ie 5", can be used to great

advantage and the intelligibility increase that results is dramatic. Oh, and note, this issue is also true in line arrays.

I will also concede that the effects mentioned will not be as dramatic in a LF config as they very much are in the MF and HFs.

As

far as going to great lengths and using an additional bass bin in an

attempt to lower the effective Fc of the bass bin, sure...I guess you

can certainly do that. And I would grant you the benefits you describe

in that config. But I would also suggest that this is of only marginal

benefit. IMO, you would be much better off using a well designed

subwoofer! And with it you get the entire lower octave and not simply a few Hz!

But I would again

suggest that an extra LaScala or two would be much better used as they

were originally intended as opposed to trying to use them to

re-engineer the base LaScala. There are much better ways to extend bass

response while avoiding the comb filtering and polar anomalies that

are only minimized by the configurations that I and a few others have

suggested. In other words, the gain in LF are minimal at best, and the

losses in terms of comb filtering and polar pattern are real and

audible.

BUY (or make) a subwoofer!!!

But I

understand that you college whiz kids have allot more energy than

money, so I guess you are fine stacking bass bins as long as you 'feel'

that the effort is worthwhile. I will grant you at least a few Hz for

the placebo effect. And while it served you (very) well in your most

ingenious use of the chalk trays in the campus AES office, it will not

serve you as well here. Now go away or I will be forced to taunt you

another time, you silly k'nigget!...[][][][*-)][:S][]

But give me a holler and I can go into a bit more detail if you desire. In the meantime you might want to practice repeating "I agree with the concepts

driving the points you're trying to make Mark"... []

** "Effective Performance of Bessel Arrays"

by D.B.Keele, Jr. presented at the 87th AES Convention in October 1989.

This should be available on his website. But if you ahve problems

sourcing it, PM me and I can send you a copy.

[DrWho]

When I get back into campus town I'll share some horn doubling simulations to demonstrate the effect. If I remember correctly, it's about a 6dB rise at the Fc, which in the case of the lascala should help bring up that 8dB plateau it has starting at 100Hz. It's certainly not a magnitude capable of placebo - ok, well maybe only if you're a musician on a stage.... []

Btw, you still haven't shared the assumptions behind the 10x interdriving spacing, nor any mathematics supporting it. Yes, I haven't gone off to read the article cuz I can't find them, but a short summary would have sufficed for me. But for what it's worth, I don't care what any amount of theory says when it contradicts personal experience. Perhaps this college boy needs to pull out his books and provide a better model than the broken one you're presenting [][]

Also, I agree that implementing proper subwoofage is absolutely vital with the lascala, but that also costs money....stacking the bass bins is a free experiment. You claim that it shouldn't sound better, but there are many that claim it does. Yea sure, it might be placebo....or perhaps just maybe, the possible issues to which you refer are of a very small magnitude. (and just to stress the point, I'm talking about doubled up bass bins, not doubled up HF/MF packs). So if I'm right, which I always am because I'm young and cocky, then perhaps you're misinterpreting the results of others? [] But seriously, I know what lobing and comb-filtering sounds like and you simply don't get it when you double up the bass bins. And in fact, I can support with the exact same theory you're trying to use to discourage the idea...[^o)] The interesting thing is that my interpretation of the theory lines up with my personal experiences with the specific application....the only thing I've left to do is some measurements to verify my position - but alas, I don't have the means to do that.

[mas]

Great! Now we got ourselves a cat fight![]

Gee whiz....the 10x distance is based upon measurements. LOTS of them performed all to the credit of Mike Lamm! Trust me, I have a full 2 " thick stack of page after page of TEF measurements. This is referenced on p.21 in the acknowledgments section. Note also, that this paper focuses on the net results, not upon the
reams of additional data that constitute the total measurements taken to establish some of
the baselines such as are mentioned above.

I am sure there is some math that will substantiate it. But after the myriad measurements that repeatedly reinforced the results, the math simply serves as a rationalization for the empirical effect.

And in the Keele paper he refers to this, for instance, in Section 4.2.1 Polar Responses, p.10 where he states "Observe that the polar responses essentially exhibit no change with increasing working distance beyond about 2.5 units (10 times array length)." Also, pp. 34-41 where two source arrays are addressed may prove useful.

As this was all done in the same relative time frame with stack and splay experiments, all of the experiments lead to the same 10X distance generalization. Unfortunately we couldn't simply find a book to read that explained all of this so that we were stuck doing the actual experiments and measurements.

Again, if you choose to simply focus on summing the bass bins, I have no issue with that. My only observation in that regards, is that with the increase in bandpass frequency, the comb filtering and polar anomalies will become present and noticeable - this is basic and fundamental - albeit with some additional LF extension and gain to which you point. (If we aren't careful, we may end up agreeing on something! [] )

My original issue was with the full combination of 2 LaScalas in a small room.

For the vast majority of music, I have no problem with the basic LaScala response. But I also love a good subwoofer, particularly one with a sensitivity that will compliment the LaScala.

And the LaScala paired with a good sub is is my preferred configuration. To each his own - Given that he has 2 extra LaScalas, count your blessings. And if you want to improve upon them, add an active crossover with signal alignment and tri-amp, and also add a good sub. If you want to improve on the design itself, build a Jubilee bass bin or a LabHorn and tri-amp them with an active crossover with signal alignment.

Have we beat this poor horse sufficiently? Or must I taunt you yet again!?

So...where to arrange a knock, down drag out thumb wrassling contest with that smart @ss college boy!?[][]

If you get a chance, give me a holler or tell me when its a good time to call you, college boy.[]

Keele(1989-10AES)BesselArrays.pdf

[DrWho]

So in that 2" stack are there any measurements of the lascala with dual bass bins? [8-|][]

Bring on the thumbs old man...lol

Btw, you can call anytime after 9pm - I'm way over on me cell minute usage.