4 way high end loudspeaker

[running123]

I am considering designing a 4+1/2 way floostanding speaker.

Does anyone forsee any problems with the following design?

2 peerless xls 10 each driven by 250w rms each in sealed enclusures of 18 litres playing up to 120 hz.

1 precision devices 8 inch mid/bass driver in a slealed enclosure driven with 200w rms playing from 120hz to 4/500 hz.

1 5-6.5 inch high power midrange driver playing from 4/500hz to 4/5 KHZ. Receiving roughly 100w rms.

1 high end dome tweeter, 50w rms ish.

An active crossover network will be emplyed before the amplification stage. Four amplifiers will be used for each speaker.

Anything glaringly stupid with this design please tell me, I want to design a floorstander which does not require a subwoofer which will play very loud very cleanly which is no bigger than a conventional large floorstander. Thanks for your time. I am new to designing hifi speakers, my goal is to comnine the high spl's of professional audio with the clarity of hifi.

[sreten]

Hi,

Frankly if you have a simple wish it has been done before. Integrating
subs into speakers has been done, as has 3-way speakers that simply
don't need subs as the bass end is more than adequate.

As ever walk don't run when you start. The only thing guaranteed if
you are new to designing speakers is you will get it wrong, and won't
know that it is wrong. Active set ups are particular prone to stick the
drivers in boxes and cross them over, it will work in a fashion but poorly.

The main problem is what you are not saying, more than what you are.

Conventional loudspeakers, by design choices, cover a wide range of
end user max SPL requirements, and there is a blur between domestic
and studio / professional requirements, many speakers cover both,
but domestically are generally used in bigger rooms at reduced SPL.

It is not the way to start designing speakers, better than anything else.
That is simply not going to happen, period, and you won't enjoy it.
The art of compromise requires extensive experience.

High SPL is the worst target for a beginner, quality is always 1st.
Understanding SPL requirements properly (for any speaker size)
is half the battle, many still get it all completely wrong.

rgds, sreten.

undefinition
(see if nothing else, the excellent FAQs)
The Speaker Building Bible - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com
Zaph|Audio
FRD Consortium tools guide
Designing Crossovers with Software Only
RJB Audio Projects
Jay's DIY Loudspeaker Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
DIY Loudspeaker Projects Troels Gravesen
Humble Homemade Hifi
Quarter Wavelength Loudspeaker Design
The Frugal-Horns Site -- High Performance, Low Cost DIY Horn Designs
Linkwitz Lab - Loudspeaker Design
Music and Design

Great free SPICE Emulator : SPICE-Based Analog Simulation Program - TINA-TI - TI Tool Folder

[running123]

HI, thanks for your rapid reply. I would like to know more about why this particular design would not work very well. I have some experience building high quality 18inch pro audio subwoofers which can develop incredible spl's, but only down to 35hz. I am fully aware that I could never repoduce 125db+ from 4 peerless drivers in sealed cabinets and certainly not down to 20hz.

If the crossover network were implemented well (and the amplifiers appropriately gain matched) what would be the problem with this design? For me high spl is an intergral requirement. I currently use a pair of wharfedale valdus 500's with a nad c370. One of the flaws with this speaker is the lack of capability of the tweeter, hence the protection kicks in regually. I wanted to design a speaker free from such flaws.

I have used them with an 18 inch fane xb driver in a large ported box and the result was impressive even though the fane only had 150w rms going to it (crossed over at 75hz), the lows were incredible and the valdus midbass presented an impressive thump. I wanted to recreate the experience of that in floorstanding speakers no bigger than the valdus. Given that the fane xb only had 150 w I would assume 4 peerless drivers on 250w rms each should be able to generate more bass than the fane sub did on this occasion.

If high quality drivers were used for the remainder of the spectrum and appropriate crossover points chosen then I cannot see why the design would not work.

Thanks for your time I greatly appreciate your input.

[AllenB]

Your needs in a domestic environment will be different. As you move into a smaller room the bass interacts with room modes. Due to this, the location of your bass units becomes critical and having them tied to the mains therefore makes little sense. This also suggests that the mains don't necessarily need to go to the low extremes.

[Lusk]

Originally Posted by running123

I am considering designing a 4+1/2 way floostanding speaker.

Does anyone forsee any problems with the following design?

2 peerless xls 10 each driven by 250w rms each in sealed enclusures of 18 litres playing up to 120 hz.

How did you work out 18 litres per 10" sealed? it seems small.

[running123]

I cannot think of a floorstander which goes as low as a pair of peerless xls 10's could do. I know valdus 500's were cheap speakers designed to go relatively loud hence bass extension was not a priority (with three 8inch drivers they barely made it to 40hz). But still even high end large floorstanders like monitor audio pl300's only go to 28hz and thats a manufacturer's spec.

With regards to having the bass tied to the floorstander, surely room equilization for each could solve this problem if it were done appropriately before the amplification stage.

Also I like to listen music really loud, in a "domestic environment" I like to pressurise the room with bass so traditional floorstanders have never been able to provide the output I desire.

Also subwoofers are just more boxes in a room I don't really want.

Thanks again for your input.

[running123]

sorry i misread your last statement. "mains don't necessarily need to go to the low extremes. " if i want only two speakers (no sub) and massive output levels is this idea a good way to go? They will be in a large room and equilised for room abnormailities.

If it still seems like a bad idea, which it may well be, can you suggest an alternative please. Thanks.

[Moondog55]

I lust after a well integrated 4-Way
I would , and have contemplated building such a beast, but really do not have the listening space big enough

1 mid bass is usually enough with the appropriate midrange and tweeter.
I would start with a 15inch bass unit and half size each next driver down for dispersal reasons, although a 10 inch midbass is a good choice.
I thought the XLS was designed and sold as a subwoofer
4inch mids and any reasonably good tweeter.
One day I'll have the money and skills, tri amping can be a good cheat but doing this passively would be a challenge.
The other thing ___ Do you have a wife or life partner who would live with the pair of refrigerators in the lounge room???

[running123]

I'm only 19....im a student at leeds university, I live in a house with 9 people and we regually listen at antisocial volumes throughout the day and night through these http://is01.thegumtree.com/image/big/86434297.jpg space is not a problem, heck if could afford it id have a funktion 1 stack in my living room.

I wanted to create something no bigger than the valdus, (even with the xls drivers its only going to be 26 cm wide if i mount the drivers flush on a double layered baffle).

Make no mistake these are going to be properly full range, down to 20 hz, which should be forcefull with 4x 10 inch subwoofers. Yes the xls are sub drivers not bass drivers, but I am using them only up to 120hz, at which point a pro audio precision devices 8 inch woofer will take over until virtually all excursion requirements are gone until the mid takes over. Is there something wrong with the xls driver? Everyone seems to think it would not work in a floorstander...

[jerome69]

No problem with this design. use a 4" instead 5-7"

2x10" 20-100Hz
8" 100-800Hz
4" 800-3000Hz
1" 3000-20000Hz

It is possible to do it in passive.
It is a big speaker, at least 11" width and 45" high.

But if you are a beginner, it will be a nightmare to tune the set-up.
There are a lot of things to know to do a correct mounting of the drivers.