Highend speaker kit with little low freq!

[darascott]

Hi, I am looking for a speaker kit set-up to suit my sitting room room.
It is a small room (about 3m by 3m) in a terraced house. The walls where the speakers will have to go will be against the neighbours wall. So the key factors are limited size in the room (and speaker size) and avoiding frequent calls from the neighbours due to high levels of low frequencies! So it looks like I cannot have all the low frequencies I want. I think what would work best are small bookshelf speakers, monitors, with no ports so that they could be sat in against the wall. Then I could add a sub woofer if necessary. I figure if I can keep the sub close to where I will be sitting the bass won't be as close to the walls and hence not travel so far into the neighbours realm. I have a audiolab 8000s amp (60w) (which I think runs better on less sensitive speakers). I used to have a pair of World Audio Design Loudspeakers (KLS9) that I built myself but they have far
too much bass for this house!!! Unfortunately!!!
So basically I'm looking for a highend kit that has an early LF roll off. I know that is a contradiction but what can I do!!!
Oh, and if a design calls for a port on the back can I put it on the side or the top? I'd really appreciate any help and advice you could give me.
Thanks,

[h_andree]

I think that most speakers can be designed with little bass.
Any of the 6.5" drivers can be configured to start to roll
off at 60-80 Hz.

You should also consider active limitations. If you know
the input impedence of your power amp you can add a
small cap between the pre and the power amp. This
can be tailored to your speaker (Typically 0.1 uF).

I doubt that the placement of the sub will affect how much
sound goes to your neighbor unless the sub is attached
to the wall. The roll-off of bass frequencies is not as steep
as high frequencies. However a sub allows you turn
the volume down (Specially at night).

Harry

[Scottmoose]

Try open baffle designs. Have a look at Siegfried Linkwitz site: www.linwitzlab.com
Open baffles don't activate room modes, or at least not to anything like the extent a conventional box speaker does. Something like his Phoenix main panel design could be the ticket, though they need equalisation, which means mucking about with amps. The site'll give you a few more ideas at any rate. Have you tried bunging the port on the KLS9 to make it closer to a sealed enclosure by the way? That could work well.
Best
Scott

[mgoedeke]

There is an alternative to Sigfried's theory which says that an open baffle excites room modes to the same extent as a monopole below the shroeder frequency becasue a room cannot support sound radiatioon by any other means than modal behaviour with the wavelength ratios involved. The listening test differences would then be down to less bass of the open baffle bacause of the 5dB reduction in power response vs. omni.

[Scottmoose]

Interesting. All I can say is that in my experience thus far, I'm with Linkwitz, but I certainly haven't heard everything under the sun. Oh, by the way -another high-end speaker with little bass? Lynn Olson's Ariel transmission line. Lovely stuff but not an easy build. it's not particularly expensive though.

[paulspencer]

I would have thought that typical floorstanders wouldn't be a problem with bass unless you turn them up too much. They will also hear the lower midrange, not just the bass. I'd find it more satisfying to just turn the volume down and listen to balanced sound with some bass than have it louder with no bass.

What about headphones?

Stereo subwoofers either side of your couch to create a "bass headphone" effect could be worthwhile. This also minimises room mode influence.

Dipoles could also help. Consider John Kreskovs subwoofer design which can be switched from dipole to cardiod to monopole - the CRAW.

[opp]

Maybe you should prioritize the systems ability to “open up” at low SPL. At the moment I am building a small system with the new Seas Excel Crescendo Tweeter and Excel W15LY, first impression is that it has a dynamic and satisfying sound at very low SPL.

[darascott]

Thanks very much all. But I'm still in a bit of a quandry. When I said high end I didn't realise how high that implied. I'd like to spend under about $600 on a speaker system. I had a look at the designs. The linkwitz was facinating but a huge job and designed for rooms bigger that mine and I have to mount my speakers in or close to the wall. I tried bunging the ports on the KLS9 but it still booms like a mad thing(it has big drivers). The speakers are too big anyway. I like the idea of two subs but I'm thinking subs will be further down the line. The ariel me2 looks interesting but seems more designed for valves. I believe my amp works better with less sensitive speakers.
SO, I'm still looking for a small speaker design that works well up against a wall or built into a wall, not too sensitive and that doesn't go to low for a small room.
I have heard that the more I fill the speaker up with wool etc the less low frq I get. Is that true? Can I take a ported design and either put the port to the front, or side, of the speaker or remove the port entierely? That should reduce bass too? Is there allready a good design the encompasses all my needs?

[paulspencer]

Sounds like you want a small bookshelf speaker mounted on a stand. If placed close to the rear wall, then you probably need a speaker without bafflestep compensation (BSC). BSC allows for the loss of lower midrange and bass efficiency as related to the baffle width and the speaker being placed away from a wall. If you put a speaker hard up against a wall, it won't need BSC. It might be difficult to find a speaker designed without BSC.

Others may disagree, but I think there are some misconceptions in your post:

The ariel me2 looks interesting but seems more designed for valves.

All good amps should sound almost identical when used within their limits. If a speaker is suitable for valve amps, it will also be suitable for solid state, but it does not necessarily work the other way, since the valve amp will likely not have sufficient power for many lower efficiency speakers.

I believe my amp works better with less sensitive speakers.

How do you figure that?

Low efficiency is not a virtue! It's the downside of placing limits on speakers, such as size, or a requirement of wide bandwidth/bass extension, etc.

All other things being equal, higher efficiency is better! In practice, however, higher efficiency means a mix of bigger speakers, less extension, horn loading, etc.

If you want to get rid of the bass (and I don't think you will like the result but anyway) ... the easy way is to make a sealed box or aperiodic. A sealed box with a 6.5" midbass driver will typically have an F3 @ 80 Hz, higher with a 5" driver. An aperiodic is a leaky sealed box with a stuffed flow resistive vent - the main advantage is it can be made smaller than a sealed box. It has a steeper rolloff and a higher F3.

I think you will find a mini monitor with a 5" driver in a vented box should be fine. Typical cheapies with an all in one system have some exaggerated upper bass, but one designed along hifi lines vented with an F3 @ say 50 or 60 Hz will have modest bass.

[opp]

Low efficient isn’t the problem I used to be – in my view. Class D amps deliver high power and high quality cost efficiently. The drivers used I the small inefficiently systems is quite good these days.

If you choose a heavy system and use absorbent feet I stead of spikes, the energy (sound) will "stay inside the room". Absorbent feet e.g. http://www.valhalla-technology.dk/vt_feet01.htm .