Decware "House Wrecker" driver selection

[Jockeylad]

Hi

I am new to this site, found it while browsing, and what an excellent site it is!

I'm looking at building Decware's "House Wrecker" sub cabinet with either 2 x 15" or 4 x 15".

Decware recommend drivers with an fs around 20 Hz, and a Qts less than .38 and a minimum VAS of 10 cubic feet.

I mainly listen to music with heavy deep bass and sometimes use it for HT. I'm hoping to get some serious bass around 25Hz and decent, yet reduced, response down to 18Hz'ish. Room size is approx 20' x 15'.
I am considering using the Acoustic Elegance AV15-H sub driver. Being from England, I have not come across this manufacturer before, but I have read some good reports on the internet. Has anyone on this forum used Acoustic Elegance sub drivers before, and if so, what do you think of them? Also where can I purchase them from in the US that will post to England?

Intended Cabinet: http://www.decware.com/newsite/hwk15.htm

Considering what I am after performance wise, does anyone know of any better design suggestions than this (ported or band pass)? I already have various horn designs for elsewhere.

Cheers
Russell

 

[Bill poster]

what internal size enclosure for an 8" approximately?

 

[sreten]

Hmmm......

A minimum Vas is specified, that is clueless, as is the whole design.
Get a good box simulator and design your own subwoofer properly.
there are lots of sites that tell you how to do this, e.g. :
http://www.subwoofer-builder.com/

One really good 15" will beat that design hands down, and be
a fair bit smaller, you simply don't need PA driver SPL's in the
home, or the inevitable lack of deep extended bass they give.

rgds, sreten.

 

[planet10]

I think that an appropriate box designed with the actual driver's TSP will handily outperform a generic box like the Decware.

John & Nick's AE drivers are some of the best there are. They are all based on early work Nick did while Llamba existed.

dave

 

[tinitus]

John & Nick's AE drivers are some of th ebest there are.
dave

hey Dave, notice that Russel is a UK/EU member

Sreten, you might be right about the 15"

In a few days I expect to receive a new 15" model from Monacor, i suppose a StageLine product
nothing fancy, and only about 100EUR
medium high Qts, so I expect it will do ok in H-frame dipole
nice and easy, I hope

 

[Jockeylad]

sreten

"One really good 15" will beat that design hands down, and be
a fair bit smaller, you simply don't need PA driver SPL's in the
home, or the inevitable lack of deep extended bass they give."

I think you may be right on the cabinet design. Sometimes it can be too easy(and lazy) to fall for buying off the shelf designs, based on loose TSP's.

That said, I have been looking around for a few weeks for the right drivers/manufacturers and reading up on forum comments etc. Having not built any speakers for some 17 years now, one can say it's been a while, but I've lost touch with who's who in the driver market etc.
Recently I've got the bug again to build some DIY speakers, and being a little older and hopefully wiser, a real nice set both acoustically and asthetically.
I mentioned Acoustic Elegance as a possible driver option. Being from Britain, which driver manufacturer/s can you recommend from this side of the pond that are up there with the best these days?
Regards
Jockeylad

 

[sreten]

Hi,

I really don't know, not being a subwoofer fiend.

But I'd look at :
RSS390HF-4 - Dayton High Fidelity Subwoofer 15 inch - Europe Audio
In a sealed box, only vented if you want very silly low extension.
Two boxes properly placed will give smmother bass than one.
Around 100L each well stuffed should do the job very well.
200L each tuned to 18Hz vented, but IMO you be better off
with (a) subamplifier(s) with some variable low bass boost.

Forget about bandpasses if you c/o low, they are waste of time and space.

Going for the Daytons as I know they are well designed with
very low distortion characteristics, lots of clean low bass.

rgds, sreten.

 

[MaVo]

"Forget about bandpasses if you c/o low, they are waste of time and space."

Why?

 

[Jockeylad]

sreten
I already have amplified subs and they're pretty good, but in order to get subs of any real decent quality I'll have to spend minimum £600+ each, and this can go up into the £thousands. I occasionally, when the wife and children are out, like listening to my favourite tracks pretty loud, and find that by using subs for the bottom end, I can ease up on the bass on my mains. I listen to all kinds of music, sometimes loud sometimes low and chilled, but I like knowing I have the flexibility. I also use them as part of my HT setup.
The main thing is that I'm well capable and up for the challenge of building them, but apprehensive about getting it wrong design/performance wise, and subsequently feeling deflated with my efforts. I am willing to give it a go, and thats why I'm on here asking for advice from people who may be able to help me avoid simple school boy errors.
So, based on my original post, I'm after design ideas that will give good smooth n distorted response down to 18Hz'ish. Any advice is appreciated and will be looked into.
By the way sreten, thanks for the link to the Dayton's they do look as though they are what I'm after.

 

[tinitus]

http://bmsspeakers.com/fileadmin/bm...dymium/15_18/bms_18n860_t_data_2010-03-18.pdf

that one will play loud

but there also PrecisionDevices, made in UK
some "force" them down with EQ

 

[sreten]

"Forget about bandpasses if you c/o low, they are waste of time and space."

Why?

Hi,

Because as you go up in frequency a drivers maximum volume increases
dramatically. Bandpasses increase maximum volume at the upper point,
only really useful for small drivers and crudely implement the top end
roll-off, often with severe port and box resonances. IMO with a decent
driver the extra front volume of a bandpass is a waste of space and time.

If you actually c/o lower than the front lowpass then its presence
becomes even more pointless, it simply doesn't do anything useful.

rgds, sreten.

 

[sreten]

sreten
I already have amplified subs and they're pretty good, but in order to get subs of any real decent quality I'll have to spend minimum £600+ each, and this can go up into the £thousands. I occasionally, when the wife and children are out, like listening to my favourite tracks pretty loud, and find that by using subs for the bottom end, I can ease up on the bass on my mains. I listen to all kinds of music, sometimes loud sometimes low and chilled, but I like knowing I have the flexibility. I also use them as part of my HT setup.
The main thing is that I'm well capable and up for the challenge of building them, but apprehensive about getting it wrong design/performance wise, and subsequently feeling deflated with my efforts. I am willing to give it a go, and thats why I'm on here asking for advice from people who may be able to help me avoid simple school boy errors.
So, based on my original post, I'm after design ideas that will give good smooth n distorted response down to 18Hz'ish. Any advice is appreciated and will be looked into.
By the way sreten, thanks for the link to the Dayton's they do look as though they are what I'm after.

Hi,

All I can say about subs are 4 things :

1) All that matters is clean displaced volume.

2) Given the above they can be EQ'd to any response.

3) given 1), the smaller the box the more amplifier power is needed.

4) Vented gives a +6dB boost to maximum very low bass levels.
(Compared to two sealed, this gives +6dB at all frequencies.)
The two approaches use ~ exactly the same box volumes.


IMO a near optimum set up would be two subwoofers, each with
two drivers on opposite faces for force cancelling, one placed
about ~2/3 along the side wall, the other the opposite ~1/3
along the rear wall, assuming floor and next to wall placement.

The size of the boxes and the drivers is related to wanted
maximum extension and maximum volume. There is no point
building a small subwoofer that goes down to 18Hz, simply
put it won't play loud enough to ever hear the 18Hz in
the presence of normal program material.

The lower you want to go, the bigger you need to think.

rgds, sreten.

 

[Reeler]

Hi Jockeylad, and welcome.

I'm not an engineer or bass builder but my experience can point you to a Spanish company "Beyma". Beyma Professional Loudspeakers
They have a distributor based in London... LMC Audio Systems

I am not affiliated to either company....but I AM biased towards Beyma as I currently use a pair of 12LX60 drivers for my bass in a stereo system. I used to want low low bass, in the way of subwoofer, but I find that these Beymas 'quiver my liver' enough when listening to loud.

Cinema might be a different thing.

 

[planet10]

IMO a near optimum set up would be two subwoofers, each with
two drivers on opposite faces for force cancelling

Geddes & Toole would want to see more, but i am 110% with sreten on a minimum of 2, each with push-push drivers.

I am currently stuggling a bit with the aesthetics of my push-push pair of sealed CSS SDX10 boxes.

An externally hosted image should be here but it was not working when we last tested it.

dave

 

[mymindinside]

Has anyone built/heard Wayne Parham's 3pi subwoofer?
it is a compact vented design using the lab12 driver. it got my attention because it is so modestly sized and yet is supposed to extend quite low (the pi speakers website says that it 'extends' below 20hz but does not specify wether it is f3 or f10)
haven't been able to find much about it on diyaudio so any impressions are welcome

this is a link to the pi speakers website where the 3 pi sub is also sold as a finished product: 3pi sub

cheers,
mymindinside

 

[Jockeylad]

I Have decided to downsize from 15" to a couple of Eminence Lab12 drivers, then build box/es to suit, as they are readily available, not too expenesive and have good reviews. They also seem to meet my requirements. I'll keep you updated on any progress, but may start a new thread when I do. Glad I ditched the idea of the Decware 'House Wrecker', as I would probably have been more of a 'Time n Budget Wrecker'!

Thanks again for the previous info.