3-Way speaker building

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No sence to make 3-way floor-standing speakers, for 4x4m room !!!!!


I suggest you to build 2-way book-shelf, for example - "Mark-Morel" speakers (designed by Mark Feldsher, Haifa).

Drivers will cost you ~1300-1400 NIS at Morel's factory (Nes-Ciona), case and crossower you can make youself, all information - at my web-site.
 
DonoMan said:
If it makes no sense, then what do you think he should do?


I've edit my message


Seems a lot of you guys look down on those of us that don't have huge listening rooms.


At 1st - it is impossible to get low frequencies in so small room (standig ways, wall reflactions).

At 2nd - 3-way speakers with usially used lower crossover frequency (300-700Hz) are not suitable to listen from the small distance! You will listen woofer and middle from the different directions.

Only one exception - if You 3-way speaker have low crossover frequency below 200Hz, but this is an expensive way (I've done this - my speakers have 100Hz F1).

More chipper way - is to use 2-way book-shelf speakers with lower freq. (-3db) near 50-60Hz (in any case - 90% of music content does not have frequencies below 50Hz, and 99% of music - there is nothing below 40Hz) and if it is still not enough "bass" - use a subwoofer.
 
3 way speakers

Hi Tald,

You may be happy with a 3 way in a 4x4m room. As regal said 3- ways have better midrange. According to my experience well designed and built 3 ways are generally better than 2 ways at most frequencies but if you were to opt for a 2 way use a good quality widerange plus good tweeter with the lowest Fs you can get. The other alternative are electrostatics. These can be brilliant at all frequencies except bass so good sub(s) is/are needed. But it is an expensive alternative.

My current listenning room is only a touch bigger than yours (4.1x4.3m) and I have a 3 way with 4 speakers: 2xDynaudio W75XL (12 ohm), Audax HM130co as midrange and Dynaudio Esotec for high frequencies. At the moment boxes are closed but will be variovented. I have variovents ready but no time to install them.

It is a semi-active system with 4th order Besseel active crossover cutting at about 600Hz (I am still experimenting) and a passive first order with impedance correction (Audax only) at 5kHz. They work beautifully in my current mini-lounge, although a large room is better for them. True, but I would not exchange them for a two way system. When I built them a few years ago I had a bigger listenning room. When I have a bigger room again I'll add some active servo subwoofers and maybe upgrade the midrange to a 5" from Audio Technology.

If you want top sound go for an active system. No passive system can compete with actives - especially at higher listenning levels.

Cheers,
 
regal said:
Personally I don't like two ways. Three ways have better midrange because the crossover is higher.

I have 2-way speakers with lower freq. 45Hz (-3dB)? and crossover at 1.5 kHz, then I add the 3-rd way, and
now crossover points are 100Hz and 1.5 kHz.

You are right, that 3-way have better midrange - due to Doppler-effect in 2-way, but I repeate again - id lower crosover poin is higher then 200Hz, in small room your drivers will sound separately - woofer, and midrange.
If you build only Hi-Fi system - its enough, but if you want really good Hi-End system, if you have good music source (not DVD-playes), good tube amplifier - DON'T USE 3-WAY in the small room if F1>200Hz !
 
tald said:
I thight about not a big 3-way speaker.
A floor standing with 8" woofer only.

Hi Tald

Check out
http://www.selahaudio.com/id96.html
Indeed all of Selah Audio's speakers are worth consideration.

Other interesting designs I came across:
http://home1.stofanet.dk/troels.gravesen

If you would like to do your own think about a 7 inch Scan Speak Revelator bass, Accuton 2 inch mid and Arum Cantus G2SI tweeter with simple first order crossovers at 1K and 4K in a sealed cabinet of say about 30-40 liters. In your room you should get some bass room gain that would complement nicely the 12 db roll off of a closed box giving good in room bass down to quite low. You will need a resistive pad to reduce the tweeter but other than that it would be relatively straight forward to design and construct. If you feel a bit more adventurous you can go for a ported enclosure and/or more complicated crossovers. But the drivers I recommended are very high quality and have at least an octave either way of the recommended crossover before they distort (actually closer to 2) so should be fine with first order crossovers.

Thanks
Bill
 
altor said:
DON'T USE 3-WAY in the small room if F1>200Hz !

Hi Altor

I own Axis LS88's which is a 3 way that crosses at about 500-600 hz and had them in a 3mX3m room and a 4mX4m with no problems at all. The only thing I noticed was the bass was more bloated than I liked which undoubtedly was caused by room gain brining up the lower octaves from its ported design - I always find ported designs bloated unless they are really low as in a subwoofer. Room modes are a bigger problem in small rooms IMHO than being able to discern crossover of the drivers in a good 3 way design.

Thanks
Bill
 
3 way speaker system

Hi tald,

You might try to build a system looking like the one shown in the attached image. I built a few such systems and they work very well. Midrange is in a separate enclosure with tweeter attached to it on its top. Using top mount tweeters has some practical advantages as it is easier to move them. Yes, the tweeter does not have to be on the same vertical axis as the midrange. The same applies to midranges and woofers.

Note the shape of the midrange box. Inside, the enclosure is profiled, using hard foam, to take a somewhat elongated spherical shape. The back of the woofer enclosure is angled.

The best 8" I ever used was Dynaudio 21W 54. There are however, two problems with this driver. Dynaudio stoped selling these to general public and more importantly, its foam surround does not last long. Mine disintegrated after 7 or 8 years - obviously did not like Perth's climate very much. Unfortunately, that is a problem with all foam surrounds. They do not last long in hot climates.

I replaced the surround with a rubber one but it is not the same driver any more. Fortunately there are heaps of 8" drivers with rubber surrounds. One of these I know and like is Peerless HDS 8". There are better drivers but Peerless is very affordable and difficult to beat in its price range and sensitivity - almost 90db @ 2.8V.

I used a number of midranges and in my current small system I have Vifa P11MH 0008 no longer produced but Seas MCA11FC (H143) is also very smooth and has similar sensitivity. It is a very detailed midrange and suitable for first order crossovers.

When it comes to tweeters you may try one of top mount Morels - MDT 41 or MDT 43. These are the only drivers I never used but a few of my diy penfriends use them and are quite happy with them. You should not have any problems with trying these (before buying) in Israel.

If you really want top sound from your system go active and try Graham Maynard's GEM amp well discussed on the solid state forum recently. Graham and Carlos seem to be very helpful. I think GEM will be my next amp project once I have finished my Stochinos.

You may also visit this site: http://ldsg.snippets.org/idx.php3#S3

You will find there reviews of various drivers and a lot of info on how to design and build speker systems, what software to use etc

Cheers,
 

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re 3way

You can reduce the modulation distortion in a two way by a large amount using the QB5 reflex alignment scheme outlined at Rod Elliots website at
www.sound.com.au
For small rooms, especially if you want to add aditional surround speakers there is a lot to be said for the two way satellite plus subwoofer system.
A thing I always keep in mind is that a well engineered two way beats a poorly engineered three way every time, and it is a lot easier to make a good diy two way.
I consider that the best bang for the buck in Australian terms at present is the Vifa p17wj, d19 tweeter combination.
This can use a third order crossover at 3.1Khz. on the tweeter, and a second order on the woofer to give an overall "Quasi L-R" characteristic, this prevents the vertical lobe wandering effect that is characteristic of other crossover types mentioned and this effect can be especially audible in small rooms with little reverbrant field.
A thing that should always be born in mind is that the crossover characteristic one actually gets is very much affected by the transfer functions of the drivers themselves and this is exacerbated in three way systems especially those having crossovers in the 300-3000Hz. band.
 
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