"attainable" End-Game System you can build in 1 day ! ( Paging Kanye )

Audio Playback
1

it has come to my attention that QSC now uses BMS Co-Axial tweeters in their Cinema line !

https://www.bmsspeakers.com/index.php-61.html?id=bms_4594nd

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specifically look at this system:

or actually just the top part of it, which is MHV-1090

the top goes for just $999 used. a horn that size alone would cost you more than that ! ! ! so what do you actually get.

a BMS coaxial tweeter and B&C mid-bass. very not bad !

and if any of them fail you can replace them either as spare parts from QSC or just buy those drivers on your own !

only real issue here is MHV-1090 may be a bit hard to find without the bottom bass section.

the bottom section appears to use QSC SP-00006-1-00 by Eminence Woofer LF-4215 which is rather MEH woofer, and probably doesn’t belong in anything “end-game” …

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so now is when we note that JBL 5732

has the same 30" width, similar depth, and the same 250 hz crossover point as the QSC …

which means you can use JBL 5739 low frequency section with QSC MHV-1090 high frequency section … though it might complicate any kind of attempts to use factory DSP presets, but nothing impossible …

now JBL 5739 should absolutely SLAP down to 40 hz, at which point you can cross it over to …

https://www.monoprice.com/product?p_id=38543

which will take you all the way down to about 16 hz. you will of course need at least like 4 of them ( one in each room corner ) to get that low.

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once you do though, you will have 5-way, system with 40 hz, 250 hz, 1.7 khz and 6 khz crossovers, a frequency response of +/- 3db from 16 hz to 22 khz and 130 db output.

and while i wouldn’t call this setup “affordable” it is ATTAINABLE, and a killer value for performance.

final note is regarding the 10" midbass used

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there is a pretty bad anomaly just above 2 khz so how does QSC get away with 1.7 khz crossover ?

well notice the PHASE PLUG they have on it !

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it is nothing crazy, but when you consider that notch is almost certainly result of different parts of diaphragm resonating out of phase a simple device like this should be able to tune that notch out …

i think the B&C may have been developed with the intention of having a phase plug installed on it, as in fact some companies make phase plugs specifically for B&C midranges. that is to say that with horn loading, rear chamber and phase plug the response of this B&C could be close to flat even before any DSP across its operating range of 250 hz to 1.7 khz …

also as the output of 10" midrange is funneled through a hole that looks about 5 inches diameter you get the dispersion characteristics of a 6" midrange with the dynamics of a 10" … a simple but effective solution.

and of course BMS coaxial with its high frequency mirrors and so on is altogether state of the art.

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here is a slow and boring video some negro made about his QSC SC-424

( you do get a pretty good look at the product in the video, which is why i am linking it )

note the mid-range horn has a higher-end construction than JBL version which has the same cheap plastic for mid-range and HF horns …

it appears QSC mid-range horn is fiberglass - the same construction as your bath tub, so quite strong - and incredible you can buy the whole system with the drivers ( used ) for less than what a quality bath tub costs !

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if you think 5-way is too complicated just think of it as 3-Way Plus Supertweeter and Subwoofer

because that’s sort of what it is.

you start with fairly established prosound tech and then you have an extra frequency band on top and bottom to extend response past 20 khz on top and below 20 hz on the bottom.

of course anybody can do that but in this case it just ends up being incredibly well integrated because the supertweeter is professionally integrated into the HF section ( by Ze Germans ) and i think those Monolith Subs would compliment the JBL Midbass Module perfectly.

JBL section is very high efficiency and low distortion but obviously lacking in very low end …

the Monolith digs incredibly deep but probably won’t have the best mid-bass …

together they should be perfect and also the fact that JBL LF section is perfectly shaped as a pedestal for the MHV ( Mid-High-VeryHigh ) section … whereas Monoliths are perfectly shaped to go into room corners …

the whole setup just makes too much sense IMO.

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all you would have to actually build is just a grille for the JBL LF section so nobody kicks the woofers in. this shouldn’t be hard.

QSC almost certainly provides Q-Sys presets for the crossover but Q-Sys isn’t cheap and you could just tune your own DSP crossovers by ear.

the other issue is cinema systems should be flush mounted into a baffle so factory presets may not work right in free-air operation anyway, unless they also have separate presets for that.

either way i think building a system from scratch ( DIY ) is dumb, but also paying crazy markups for branding is dumb too … with this approach you avoid both. you pay barely more than the cost of raw materials the system is made out of and you get state of the art technology and outrageous performance.

it’s almost too good to be true.

i am sure there are downsides to this approach but there are downsides to everything.

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essentially the appeal here is you get to build something unique without having to breathe saw dust for days on end and what you build has performance that almost nothing surpasses in either absolute terms or in terms of price / performance ratio …

you could of course just use QSC top with QSC bottom or JBL top with JBL bottom but then it wouldn’t be unique …

i really do feel QSC has the better top here because BMS coax is cutting edge while JBL cinema speakers still use previous gen JBL dome drivers ( latest JBL drivers are also coaxial ring radiators, which is just the new way to do things in general ). in fact JBL now rebadges BMS drivers in some products. so the BMS is definitely a full generation ahead of what JBL has in their cinema line currently.

on other hand Eminence is bottom of the barrel and clearly QSC uses their woofers in the LF section to save money where they think nobody will notice the difference. they are probably right. but if you can get a JBL LF section with genuine JBL woofers - why not ? you may not notice a difference but at least you won’t be embarrassed telling everybody what woofers you got in there.

and Monoprice is trash of course but it’s only below 40 hz and it’s a great value for the amount of output you get there.

you are probably thinking - but if there is nothing below 40 hz why waste money ? because subwoofer crossovers are not brick wall so with 40 hz crossover those Monoliths will still be contributing even at 60 hz and you will feel the difference in how deep the bass kick hits.

the JBL LF section by itself should kick pretty hard but it would be a fast / tight kick whereas with the monoliths in the equation it will become a deep / lush / bottomless kind of kick that rolls in waves and rattles the furniture …

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anyway my point was that you can use the full +/- 3db bandwidth of the JBL ( which is down to 40 hz ) and then still cross over to Monolith using the integrated low pass which also goes to 40 hz.

but you DON’T HAVE TO use 40 hz of course !

you could probably go up as high as 80 hz or use any other point between 40 and 80 or so.

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other subwoofer options include BassBoss ZV28 MK3

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or used JBL VTX G28 which was sadly recently discontinued, but not like anybody would pay the $9,000 new price anyway. used you get two G28s for $8,000 which and even if all the drivers are blown it will still be cheaper to replace them than pay new price.

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both of them will do about 24 hz, which isn’t as low as 16 hz of the Monolith but low enough, and they will go much louder.

BassBoss is powered whereas G28 is passive. each approach has its cons and pros.

the lowest crossover point for BassBoss is 65 hz … which would still work here.

the other cool thing about BassBoss is it has feet on two sides so it can be used horizontally or vertically. it is also a more compact design and in general i think better suited for casual use.

the G28 by comparison is somewhat over-specialized for professional use, but because it was widely used you can now get it used at a price that beats the new price of BassBoss and the only component likely to fail ( the driver ) is also easy to find a replacement for.

in BassBoss you should be able to replace the driver too, and if the amp fails you would just convert it to passive …

what the two of them have in common is the DEEP cabinet, which allows for both higher volume and longer ports and therefore lower tuning. although they’re both designed for music and thus have no subsonic output they are on the DEEP end of prosound music subs and that’s what you want.

they may not be ideal for movies but with a few extra HZ reach over mainstream PA subs you are future proofing yourself such that as bass in music keeps getting lower you will be there already …

so you’re basically paying for the cabinet, which for DIY seems insane, but to me DIY doesn’t mean cutting plywood. i did that in the past and don’t want to go back there. the system would still be assembled from a number of parts that were never meant to work with each other or in this application -so it is still a DIY project IMO. just not a carpentry project.

of course if you want to build your own subwoofer you can do that too. will save a lot of money at the cost of breathing carcinogenic saw dust and potentially losing fingers, as well as having a final product that maybe doesn’t look as polished - but the $$$ savings will be massive so i certainly don’t blame you if you go that route.

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this is the supposed response of ZV28

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this is lower than most cinema subs, but unlike those it has a grille and handles, which is a nice bonus IMO.

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Where would I put these giant speakers?

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i have to admit Kanye i have a personality flaw that causes me to over-prepare and over-design.

for example i just took about 15 pounds of dried foods with me on a weekend trip to Florida … that was realistically enough food for a month.

but the food won’t spoil or anything - i will just have to bring most of it back - no problem.

likewise you put these speakers in your living room so you never have to worry about reaching their limits … the fact that you will never tap into the last 20 decibels or so of their capacity shouldn’t be cause for concern.

the other thing is you should try musicians earplugs - i recommend Westone as all around best product ( much nicer than Etymotic Research i used previously )

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these will lower the noise floor in your room a solid 10 decibels or so and allow you to feel the bass in your chest without going deaf.

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the thing is you won’t save that much money by going to a lower output system because most of the $$$ in a system is in subwoofers and subwoofer amps, and it is almost impossible to have too much deep bass.

and if you’re going to spend $10,000 on subs for truly impressive bass you may as well spend another $10,000 on the rest of the system - of course that will leave you with about 20 decibels more than you need - but so what ?

it would be equally if not more silly to have $1,000 mains mated to $10,000 subs even though that setup would work fine.

i had a setup where i paired nearfield monitors with a 18" TC Sounds LMS Ultra sub and actually the sub was giving out before the nearfield monitors but it was kind of silly IMO to have 4X as much money below 80 hz than above 80 hz.

IMO you build the subs with the max output your walls can handle without cracking drywall and then whatever it ended up costing - match that budget for the mains. if the mains end up having SPL reserve - so be it.

that SPL reserve will ensure low distortion at playback levels at which you show a system off, which is about 100 db not at levels at which consumer speakers are measured which is like 80 db …

even though in normal listening you probably won’t be over 80 db that isn’t when it really counts. when it counts is when you’re high on crack and showing the system off to your friends, and you will be way over 80 db then.

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personally i also find it reassuring when i can turn the volume knob past any level i would ever listen at and have the system not show any signs of strain …

if i can do that i know i am listening at MY preferred level not at the level the system prefers …

if you can find a level at which the system begins to strain then you will never have the satisfaction of knowing you can go to any volume you want …

i want the FREEDOM of not having to think about how the speaker is going to handle what i throw at it - i just want to be able to crank it to whatever setting sounds good to me at the moment ( when i may be high and / or wearing earplugs ) and know the speaker will easily handle it.

with consumer speakers its like walking on egg shells. i want to feel like i’m driving an Abrams tank and can just drive through a wall if i feel like it.

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background noise level at home is about 40 db so if you’re listening at 80 db you only have 40 db dynamic range …

-40db distortion = 1%

so any distortion less than 1% will be buried under your room’s noise floor …

audiophools worry if their DAC has 0.001% or 0.002% THD when those are totally swamped by room noise floor and if they were to crank their system up to 100 DB to actually distance from the room background noise then their strained speakers would hit like 10% THD again defeating the purpose of having a clean DAC

try listening to music in a car while driving with windows open - it sounds distorted - but it’s not distortion - it’s just that ambient noise sounds pretty much the same as distortion - both ultimately bury detail, unless we’re talking 2nd order harmonics added for warmth in which case it obviously has different effect.

anyway, reality is that DAC, preamp etc - none of those things matter unless you can get like 60 decibels above ambient noise at which point you’re at rock concert levels and should be wearing earplugs …

well, or if you live in an anechoic chamber in which case you only have to overcome the sound of your own breathing…

people should worry more about SPL and less about THD but audiophilia is a circle jerk for old jews flashing cash rather than about people actually passionate about music.

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that said there have actually been studies ( in the prosound industry ) that showed people prefer louder music when they are drunk ( no surprise )

which means that while 100 db may be appropriate in a club where you will almost certainly be drunk it may not be at home where you will likely be sober …

basically 100 db is what you want when you’re drunk and wearing musicians earplugs like Westone

80 db is what you want when you’re neither drunk nor wearing earplugs

however my proposed system can also play at 80 db whereas some audiophool system won’t be able to play at rock concert levels without sounding strained or risking damage …

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IMO you only have to worry that system’s self-noise doesn’t actually exceed the noise floor of your room, and if you have a 130 db system with 100 db SNR you are approaching that point where it could be an issue …

in practice this means you will need a very clean amplifier on the HF section ( that is about 110db/watt sensitive ) some people go so far as to use headphone amps on compression drivers but i would rather try to find some ultra high end low-power studio amp instead. something like 30 watts.

most electronics are pretty clean below 1 khz so you will probably not have a problem with other frequency bands than HF Compression driver.