A good three way must trounce a two way. Better directivity for one thing.
What you do is find a very efficient 4-5" mid, and relieve it of bass duties which lead to distortion, and top end duties to avoid cone breakup. Maybe 500Hz and 3.5kHz crossover.
If you pick a flat and efficient 90dB mid, you can then give it an impedance correcting attenuator which makes the filter and impedance dead easy, and it all works out nicely.
I would fancy a BW3 three way, but the classic 2nd order bass and 4 element mid plus third order tweeter is one way to go. Mid and tweet are offset to the centre to reduce diffraction issues.
What you do is find a very efficient 4-5" mid, and relieve it of bass duties which lead to distortion, and top end duties to avoid cone breakup. Maybe 500Hz and 3.5kHz crossover.
If you pick a flat and efficient 90dB mid, you can then give it an impedance correcting attenuator which makes the filter and impedance dead easy, and it all works out nicely.
I would fancy a BW3 three way, but the classic 2nd order bass and 4 element mid plus third order tweeter is one way to go. Mid and tweet are offset to the centre to reduce diffraction issues.
Attachments
Thumbs up for smaller midrange, 3 and 4 ways and multiple subs. I use a 1" seas magnum tweeter, a 5" C82-T8, 3x18W classic and 3 x 12" XXLS 830952. It works great!
My room is asymetrical and with some walls at 45 degrees due to the roof.
Seas has some ragging at 19Khz, cant here em.
Accuton has a breakup at 4800hz - PEQ in the DSP and crossed at 2700hz with 24LR.
3x18W because I got them cheap and - well I could - and it looks nice - and gives alot of headroom.
3x12", because they're cheap, great sounding and takes the heat.
Crossed at 80, 450 and 2700.
Only had 2 channels for the subs. My amp is big enough to bull 2 x XXLS in parallel, so I simply coupled two out of phase and moved the third sub, so that the phased aligned with the rest. Of course the volume increased with two in parallel, but that is simply managed by turning down the volume in the DSP for that channel.
So make two good 3 way's and ad 3 small nice subs, and I'll bet you'll have a very nice sounding system
I've seen ok results, simply by adding a sub to fullrange fronts, but I would prefer more than one sub to even out the lower octave.
My room is asymetrical and with some walls at 45 degrees due to the roof.
Seas has some ragging at 19Khz, cant here em.
Accuton has a breakup at 4800hz - PEQ in the DSP and crossed at 2700hz with 24LR.
3x18W because I got them cheap and - well I could - and it looks nice - and gives alot of headroom.
3x12", because they're cheap, great sounding and takes the heat.
Crossed at 80, 450 and 2700.
Only had 2 channels for the subs. My amp is big enough to bull 2 x XXLS in parallel, so I simply coupled two out of phase and moved the third sub, so that the phased aligned with the rest. Of course the volume increased with two in parallel, but that is simply managed by turning down the volume in the DSP for that channel.
So make two good 3 way's and ad 3 small nice subs, and I'll bet you'll have a very nice sounding system
I've seen ok results, simply by adding a sub to fullrange fronts, but I would prefer more than one sub to even out the lower octave.
Ok, this is weird. I know schlager privately - and my browser apparently remembered our last meeting, and him using my computer to show some horn calculations.
So It was actually me, writing the above text about multiple subs and the like - forgetting all about being logged in as him - sorry about that
Admin is so very welcome to move the text - if it can help clean up
So It was actually me, writing the above text about multiple subs and the like - forgetting all about being logged in as him - sorry about that
Admin is so very welcome to move the text - if it can help clean up
Erik - could you please provide details about these speakers. They sound like what I need to build. Thanks,
Rick
Apologies, poor choice of words I should have said absorbers of sound. Or similar to a panel constructed like the walls of an anechoic chamber. They diffuse the sound by scattering/diffusing and prevent re emission by absorbing what's scattered.
I run my subs up to 150hz without any problems with localisation. I don't know why you want to obsses so much about the 100-400hz range. Below 100hz is where room modes cause the biggest issues and early reflections within the 100hz-400hz range are the least likely to degrade the illusion created by stereophonic reproduction. What linearity issues (and their causes) are you specifically looking to combat within the 100-400hz range?
I wouldn't exactly go that far. It is scientific fact, proven both by simulation and then practical implementation that multiple sub approaches are excellent at controlling the modal region of a small listening rooms.
It is also scientific fact that controlled directivity, either by wave guides, driver configuration (a la B&Os latest beolab) or implementation (dipoles) are an excellent way of attending to the other issues that a room can present itself with. Most notably the wave guides or beam width steering from the beolab.
From the point of view of what we hear, an uneven bass response is extremely unpleasant, especially if you want (and you should want) a system capable of extension down to the limits of human hearing. Smeared, imprecise imaging with tweeters that call attention to themselves and spitty treble are a product of early room reflections and wide dispersion and are extremely unpleasant. Wave guides specifically help manage these and you don't need much of a wave guide to get appreciable results. The SEAS DXT tweeter doesn't control directivity very low in frequency but already you can appreciate what it does. Going bigger only improves things further, but it's mainly the upper frequencies that benefit the most as these are where we get our localisation cues from.
The 100-400Hz issue? What issue? Take your subs up to 150Hz for a start. With multiple subs localisation becomes far less audible, no sub produces a tremendous amount of output by itself so doesn't draw much attention to itself. I run 150Hz and have a sub right next to the listening position to the side wall and cannot hear it - ever -. The higher up you go the far less of a problem modes become because they are so tightly packed.
Then you've got floor bounce and to a less extent ceiling bounce. You can eliminate floor bounce with floor mounted woofers in three ways. With a floor mounted woofer the bounce to the ceiling and back down is pushed lower in frequency to the point where the multiple subs cover it up.
If you're going to choose to worry about early reflections relatively low in frequency grab yourself a cardioid or a dipole to cover from 150Hz and up to wherever you want it to hand off.
All of these things are more attractive to me than any kind of room treatment. The goal, imo, is to have a system that goes into your room -without- you needing to modify the room in any way to get the sound that you want. People often say that the room plays an extremely important part in how your system will sound, but this is only because your system interacts far too much and in the wrong way with the room.
I get the impression that you're not. Trouble is I'm only a proponent because it works, both on paper/technically/scientifically as to why it works and in principle when you actually implement it properly.
As this topic has been already derailed I won't respond in length and only to say that it erks me when people tell others what they do or don't need, that because they didn't implement something properly themselves it automatically won't work for anybody else, that their way is the only way and then dress up their opinion as a fact that can be applied to every person ever born.
Now can us heathens please have our own DIY room treatment sub-forum?
Now can us heathens please have our own DIY room treatment sub-forum?
Hi Rick,
Sorry I pretty much left this post.
I used ScanSpeak 6.5 Revelators and got great bass in room with a ported cabinet. There are lots of designs out there that use the Revelator or more expensive Illuminator which (very broadly) have similar bass output. Of course, the Illuminator is more expensive, is rated for higher power and at least from a technical perspective is the better driver. I've not heard it compared to the Revelator so I cannot compare it's sound. The Revelator is VERY good however and has a smoother top end making it easier to integrate.
You can find good examples of these types of kits at Zaph and Madisound and other locations I'm sure.
There are also lots of fans of the SB Acoustics Satori line as well, which I have no experience with either, but I've heard people I respect talk them up so I'm sure they're another good choice fora 2 way. Their price makes them a very attractive alternative.
Best,
Erik
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I hardly call the scientific research and papers written by the various authorities usually quoted blindly stating opinion. I detailed quite clearly the objective reasons why the principles discussed worked at doing what you want them to do. If your end goals are different then that's fine. I am not saying that room treatment cannot be made to work if done well, but most wont do it well, much like most wont do multiple subs well, or even bother trying in the first place. I mean how many out there are going to measure and research room reverberation time constants in combination with researching the effect different panel types have on the sound field? Then going out and buying/experimenting with what's necessary to get the job done correctly? Very few.
This wasn't supposed to be a derail it was supposed to be informative.
My advice to the original poster is to build a 2 way with a 6.5" midbass and a wave-guide loaded tweeter. Then to buy 3 decent second hand subs from ebay (like the ones listed) and implement a multiple sub system. I would suggest buying a behringer DCX2496 or miniDSP board for handling the EQ on the subs though.
All of which could be inferred from what I had written - multiple subs and constant directivity.
Is there a reason why not go with 2.5-Way? I had a pair of PSB T45 2.5-Way, and in my HT system they sounded really good, also for music, it was a very dynamic speaker and I wasn't missing anything. I had a small 8" and with music it filled in nicely, with HT it would perform more than adequately in my 14' x 17' room. Have the OP given any thought to a 2.5-Way?
Depends how much you like and/or want low frequencies.
To me personally a 3-way with a 30cm or larger woofer made from random drivers picked blind-folded off of an online speaker store is better than a 2.5-18cm 2-way made from diamond-beryllium-ceramic-sandwich cone.
If that 2-way has a subwoofer, then the 2-way is better.
To me personally a 3-way with a 30cm or larger woofer made from random drivers picked blind-folded off of an online speaker store is better than a 2.5-18cm 2-way made from diamond-beryllium-ceramic-sandwich cone.
If that 2-way has a subwoofer, then the 2-way is better.
That means because you need/prefer low frequencies, not sound quality in general (there are many variables!). So it is necessary to setup/specify a minimum threshold for the LF response, regardless of 2-way, 3-way or 4-way.
Less expensive but still quality drivers in a well-executed three way would be my preference to more expensive drivers in a well-executed two way, for cone 'n dome systems. A three way can be tuned carefully to almost completely eliminate floor bounce, and unloading the midrange from bass duty means that midrange distortion and power handling can be made into non-issues with reasonable drivers.
Another thing is that a two way needs at least a 6.5" to deliver satisfying bass- which is hard to cross over to a dome without at least some narrowing directivity below crossover, or a too-low crossover for the taste of most good domes. With a 3 way you can use a small mid and a higher XO and solve that problem.
Another thing is that a two way needs at least a 6.5" to deliver satisfying bass- which is hard to cross over to a dome without at least some narrowing directivity below crossover, or a too-low crossover for the taste of most good domes. With a 3 way you can use a small mid and a higher XO and solve that problem.
I think it's been said a number of times, the difficulty is finding three way kits that excel at using the best of the cheaper drivers. For while you can get 90%+ of the performance of the revelators etc, for a fraction of the price, only certain drivers will do this and mostly only when used in a certain way.
I mean I'd want to use something like an RS225, ZA14 and DXT tweeter, if you just want off the shelf parts.
The Finalists would make for an excellent cheaper three way design. The value proposition is high, it does what you want in a three way - better bass and midrange than the ubiquitous 6"+1", so that's good. The only problem is that if you were starting from the ground up you could use a cheaper midrange driver and tweeter to squeeze out more bang for your buck, but that wasn't the point of the design.
Personally I'd want to go with a waveguide or coaxial design, but there aren't many of those around. A SEAS MR18 + RS225. Or an XT25 + Visaton WG 148 R, 5" Satori on midrange and a RS225 below it. Trouble is they haven't been done.
I mean I'd want to use something like an RS225, ZA14 and DXT tweeter, if you just want off the shelf parts.
The Finalists would make for an excellent cheaper three way design. The value proposition is high, it does what you want in a three way - better bass and midrange than the ubiquitous 6"+1", so that's good. The only problem is that if you were starting from the ground up you could use a cheaper midrange driver and tweeter to squeeze out more bang for your buck, but that wasn't the point of the design.
Personally I'd want to go with a waveguide or coaxial design, but there aren't many of those around. A SEAS MR18 + RS225. Or an XT25 + Visaton WG 148 R, 5" Satori on midrange and a RS225 below it. Trouble is they haven't been done.
Yes you did. Except the threshold part. I mean, before deciding with 2-way or 3-way, the first thing to do is to set the limit for LF extension. We can set 20Hz, 30Hz or whatever, but IME there is a minimum where above that, whatever the quality of the drivers (beryllium, diamond), it is useless because too many (if not all) music is then lost.
I think it's somewhat hard to beat the different 3-way classicals constructed by Troels Gravesen. The new version is using SB drivers that are cheaper, but then the filter components are more expensive and they all end up at around 560 $ + cabinets and shipping if bought outside of Europe.
I guess that it will be difficult to do it much cheaper, but I would like to be proven wrong
I guess that it will be difficult to do it much cheaper, but I would like to be proven wrong
Troels uses ûber expensive xo parts, xo cost can easily be halved without compromise in sound quality.
Here is a high value 3-way floorstander (sorry in Finnish, please use Google translate) price 390€/speaker for electronics. Kaiutinrakennusohje - Kolmitieklassikko - perinteinen lattiakaiutin 12-tuumaisella bassolla | AudioVideo.fi
Here is a high value 3-way floorstander (sorry in Finnish, please use Google translate) price 390€/speaker for electronics. Kaiutinrakennusohje - Kolmitieklassikko - perinteinen lattiakaiutin 12-tuumaisella bassolla | AudioVideo.fi
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