Building a nice Subwoofer - questions.

[jwmbro]

Hello!

Thanks to the help of everybody on this forum I have build myself a nice surround set, consisting of 6 Zaph ZBM4s. Great sounding speakers, but obviously a bit lacking below 100Hz, given their size.

So I'd like to build a Subwoofer to compliment them in the range 20Hz - 120Hz (or as far down as I can reasonably expect to get). There seem to be less premade sub designs online than speaker designs, so I figured how hard could it be to do some design work on my own now... after all, no crossover to worry about.

I'd like to build a small box, for a small room. The room is around 50m^3, which is 1800ft^3.

I'd like to keep the box somewhere between 30cm cubed and 50cm cubed, which subtracting bracing and cabinets, would leave me with around between 20 and 85 liters. And I'd like the sub to be cheaper than my speakers, so maximum budget of 400€/400$.

I'd like to either use a european/scandinavian driver, or at least something that is available to buy here in Germany or Europe (though it's not vital, assuming a deal can be found in the USA that is better than the loss in shipping and handling).

1) I was looking at the Peerless XLS, based on their availability in Germany, and the fact that Linkwitz seems to like them. Are these any good for my purpose? Option would be to use 1 with a passive radiator, but that wouldn't leave much budget for an amp....

2) What sort of T/S params am I looking for in order for a woofer to be suited for this sort of application? I only have very fundamental understanding of the meanings of the params, but not of how they affect sound. If I had to make a random guess, I'd say high Q for dynamics, and large Xmax and P for the small box size... though I'd probably be wrong.

3) Amps: I notice most of these have an adjustable low pass. Are there also amps that have a high pass at the same freq. before the line level outputs?

4) Would rather the sub be more musical and dynamic, rather than home cinema loud and rumbly.

5) I have WinISD, what other programs are good for modeling?

Oh, and I'm really not too picky about the design I build... sealed, vented, passive radiator, bandpass, (dipole?)....

[tinitus]

Originally posted by klankymen
Hello!

I'd like to build a Subwoofer to compliment them in the range 20Hz - 120Hz (or as far down as I can reasonably expect to get).

3) Amps: I notice most of these have an adjustable low pass. Are there also amps that have a high pass at the same freq. before the line level outputs?

4) Would rather the sub be more musical and dynamic, rather than home cinema loud and rumbly.

Hi, I will try

Amp http://www.reckhorn.com/index.php?ln=de&prod=a400

One advantage with a "stand alone" is that its practical to use just one amp with two subs, but its also good value with very nice funtions, and made in Germany

Fore music sub to around 100hz I would certainly use double subs, but as said above you can still do with a single mono amp
You may have to let go of the deepest octave, which makes this bargain woofer a possible choice....... 10" DAYTON RS270S
Should work nice in closed, and amp has Eq
Cannot link directly, you have to look fore it, at the bottom of DAYTON side

http://www.intertechnik.de/index.htm...2595&suchwort=

[The golden mean]

Hi,

there are of course the Visaton woofers in Germany. As an alternative I would like to recommend English Volt drivers; their Studio range.
I use two subs which are very solidly made (about 100 kg/each) and one Volt Rv 3143 (12´ driver) in each of them and after "fine tuning" the system for some years I think I now have a bass reproduction I thought was impossible to achieve, at least in this room . I use a lot of room tuning. The enclosures are BR and they are supplemented by Accutone /Thiele & Partner
C220 in closed boxes. Some say the BR principle can´t lead to a tight bass but as I mostly listen to Reggae, Disco, Afro Beat and "World Music" there isn´t anything to complain about.

I understand there is hard to take someone else´s word for it, but I´m a bit of a perfectionist so saying I am satisfied with the bass reproduction may mean something good.

A closed box may be easier to manage and with some compensation a very good result is possible. Look for a Qts value of about 0.35 or lower for a bass reflex box and a somewhat higher Qts for a closed box. Vas should be moderate say up to 80-90 liters will be acceptable.

Using the built in high pass filters in a sub amp would probably degrade the mid and treble thus I advice you to stay away from using this facility.

The Volt drivers I recommend is the Rv3143 or the B2500.

The prices are rather high as you can see.

https://secure.wilmslow-audio.co.uk/...217167eabfb5cf

You can check the Volt site for T/S parameters.

There are a lot of alternatives for your project. For my part I have searched a lot for a 10´woofer for a sub project intended for a friend of mine. The problem is that he wants a very small sub and this restriction diminishes the alternatives. We will probably go for an Aurasound NS10-794 in a 30-35 liter closed box.

[tinitus]

Just fore the record

My previous suggestion uses exstremely popular woofers and amp
Its even dual woofers
Top notch quality, and still close to the budget of 400 EUR
The use of 10" Dayton RS270S may not give you 20hz, but will excell upwards instead
Its well thought through

[The golden mean]

Hi again,

the problem with questions like yours is that you may get some or a lot of answers and still be confused what to chose. There is often a tendency to present the suggestions as "the solution" but the problem and its solution is up to different taste, equipment, room acoustics. etc.
The advice I can give is to play around with some (free) interactive loudspeaker simulation program. How different T/S parameters give a certain (predicted) result. Check the web for sub simulation or interactive speaker design. Her´s a link but I could not endorse it since I mostly use the SoundEasy program (which isn´t for free).

http://www.pvconsultants.com/audio/boxmodel/subsim.htm

In Germany there is as you probably know the magazine Klang+Ton and e.g. in the 4/2008 issue there are some Visaton equipped subs under review.

Regards

Håkan

Uppsala
Sweden

[madam]

Or try this one

http://www.northcreekmusic.com/Thunder/ThunderInfo.htm


It's slammin'

[The golden mean]

Passive radiator solutions have their drawbacks like steeper cut-off beneath their operation area (than ported or closed box designs). Long-throw elements aimed at high SPL may be nice if you intend to play music this way but might lack some finesse and subtlety when playing at moderate levels in my opinion.

[The golden mean]

I agree to a degree to what is written on this site.

http://www.zaphaudio.com/lowxmax.html


Loudspeaker design is a quite complex activity. I distrust such simplifications as "use a woofer with a large excursion and you will be happy".


Happy in what sense? There´s more to music than plain high SPL.
I get happy when listening to speakers were the bass note´s pitch is easy to follow, where dynamics is evident and some "holistic" appearence (hard to define) is sensed.

[jwmbro]

First of all thanks everybody for their replies. It's now time for me to get back to my subwoofer project.

Originally posted by The golden mean
there are of course the Visaton woofers in Germany.

Thanks. I have of course heard of those, and read it recommended on German forums such as hifi-forum.de

The problem is, that the people on the German forums only use like Visaton or Mivoc drivers (with a few rare exceptions, but not many). I'm probably forgetting a couple brands off the top of my head right now, but what I'm trying to say is that the Germans only use German brands, and I can't find any comparitive reviews between for example a Visaton and a Peerless, so even though I find positive reviews of a Visaton driver in a German magazine, I have know idea if that means it's better or worse than something from an American/Internation review. Cause nobody outside of Germany/Europe really seems to use Visatons.

So the thing is I have a hard time chosing between 2 products if I don't have a good comparison.

I COULD order from the UK or the USA also, though Germany would be the simplest.

[smithy666]

I just finished a subwoofer based on a Scan-Speak 23W in a 37L sealed enclosure, which I am using with Dave Ellis's 1802s, and they are a really nice fit. You get some great low bass - very tight. Not that efficient (I am using a 200W amp to drive one), so if you are looking at high SPLs, one would not be enough. But if you are looking for audiophile quality at normal listening levels (these will still play loud), then I strongly recommend them.