2-way or 3-way?

GAK

Member
2001-04-05 10:05 pm
Greece
I want to build new speakers for my system and I'm wondering "2-way or 3-way"?And why?
I have my answers but I'd like to have some other opinions
Any suggested desing?
I'll use a tube xover with a 20w p-p el34 amp for low freq and a SE amp for high freq.
My listening room is about 3,5m*7m.The speakers are placed about 2.5m from the back wall and 0.5m from rear walls.And I'd like the new speakers to stay at the same place.
 
GAK,
Talk about opening a can of worms...I left this for a bit to see if anyone else would take it up. No one did. Now I'll drop in a few words and we'll see if I can create a riot.
Two way:
Points in favor--cheaper (you're buying fewer drivers), fewer crossover points (crossover points induce phase shift and other sundry nasties)
Points against--you (arguably) won't get as good a bass response (generally the tweeter is going to reach about as high; the compromise comes in the low end), you're asking more of the two drivers in the sense of how many octaves they cover, hence distortion is higher (IM)
(Footnote: One of the things I find most sad/hilarious about those who feel that amps with a skillion zeroes behind the decimal point are the ne plus ultra is that they are frequently blissfully unaware of the fact that their speakers are generating distortion to the tune of entire percentage points. So what's the point of getting all weirded out over the difference between a .001% amp vs. a .0001% amp when your speakers are generating 8% distortion? Jeez, get a life.)
Three way:
Points in favor--better coverage of the audible spectrum, lower distortion
Point against--you've got more drivers to match, tonally speaking (think of the poor examples of electrostats mated with dynamic woofers for an extreme example of this problem), expense, and phase shifts, larger cabinet to have to place
Okay...so where does that leave us? Me? I think you're on the right track with an active crossover. Tubes for bass? I dunno. I love tubes for mids and/or top, but can count on one hand the number of tube amps I've heard that were really good at handling things below, say, 100 Hz. (Implied question, here: How low are you intending to go with these things?) SE (tube, I presume) for top...go for it. But if you go for 3 way, what will you do for amplification?
Oh, and the usual raft of questions left over from when I used to sell this stuff:
1) What kind of music do you listen to?
2) How loud?
3) What characteristics are important to you? (I'm making an assumption [from the placement of your speakers] that you are at least somewhat into imaging, yes?)
4) Do you intend to add a sub somewhere down the road? (If so, lighten up on the woofer end and live with compromised lows until the sub shows up.)
Back to you...

Grey
 
2-way or 3-way

Gak: I'd generally agree with Grey. I'd add a comments about the choice of 2-way vs. 3-way. It sounds like you might have additional complexities driving a 3-way with what you indicate above.

In general, I would prefer to build a 2-way for several reasons - I'm currently scoping out either a Northcreek Revelator or the BESL System 4.5k (both are MTMs using the same scan-speak drivers, the basic difference is the cabinets). In addition to (possibly) getting away with spending less money, you may also get some higher efficiency using an MTM 2-way because the mid-bass drivers are often arranged in parallel which doubles their efficiency over driving a single driver. Using lower-powered equipment, this might turn out to be important for you.

The other issue comes down to your preferences. If you prefer to listen to jazz or classical music, you might want to tend toward 2-ways. If you much prefer bass-heavy materials such as pop or rock, you might want to lean toward 3-ways. However, I could be inclined to extend the above argument to the vented vs. sealed enclosure argument for a 2-way. Of course, there is always the option of adding a sub to the system to pick up the lowest octave in either case.

In general (2-way or 3-way), you want to make sure that mid-bass driver is (typically) no larger than 6" or 17cm in diameter. Often times, when the mid driver is larger, there is poorer integration between it and the tweeter.

Hope this helps a little...
Eric
 

GAK

Member
2001-04-05 10:05 pm
Greece
OK I agree with everything but I think that there must be and another question:
How much is the area of your listening room?
Isn't this important for the choice of 2-way or 3-way?
I think that I'll be ok with a 2-way MTM in a 25m2 listening area.Or,I'm wrong?
GREY:I suppose that you don't agree with the placement of my speakers.But I can't put them somewhere else.Anyway,where do you think to put them for better results?
 
Room Size

GAK: I don't really see room size as a 2-way or 3-way question. IMO, appropriate speaker selection for a given room size is a function of 1) how loud do you like to listen 2) the efficiency of your speaker and 3) the power of your amp.

The efficiency of your speakers is not typically related to the 2-way or 3-way issue in my mind... Look at Lynn Olson's Ariel design, its a VERY efficient 2-way MTM. I think its rated at 95dB sensitivity. I've also seen 3-ways that are pretty efficient.
 
GAK,
Like Eric, I don't see room size as relevant to your original question--2 or 3 way. Your room is roughly the same size as mine. I listen primarily to jazz, classical, and a little rock at realistic volumes for each style, i.e. low to medium for jazz (I prefer smaller combos to big band--if you want big band jazz at realistic volumes, you'd better plan on a beastly system), low to loud for classical (full symphonic stuff, not [usually] chamber music), and moderate to immoderate for rock. My speakers are only so-so in efficiency, so I need a decent amount of juice to get the ball rolling. You haven't specified what you listen to, or how loud, but it will matter. If you're prone to solo vocal works or piano recitals, it's going to be a whole 'nother ball of wax than if you're wanting to play Metallica at concert volumes.
I'm sorry if I gave the impression that I dislike imaging. To me, it's one of the most important characteristics of a good audio system. I was just guessing from the placing of your speakers, and the general trend of your equipment choices as to what you might be aiming for. Pretend I'm like a doctor...if you don't tell me where it hurts, I can't fix it. If imaging is important to you, say so, and we'll try to optimize imaging. (Note that imaging is generally going to be a low priority for someone who likes Metallica.)
In that context, you said above that your speakers are 2.5m from the back wall, and .5 from the rear (sic) wall. Would I be safe in assuming that the .5m measurement is from the side walls? (Otherwise we're going to have to define some terms: rear vs. back.) If you're into imaging, and if the .5m is from the side walls, and if you can manage it room-wise, try moving the speakers out to, say, 1 to 1.5m from the side walls. (Even if you have to constantly move them out when you want to listen, then put them back when you're done.) Note that this has implications for the 2 vs. 3 way question, as smaller (presumed 2-way) speakers are going to be easier to move.
Are you planning on stands?

Grey
 

GAK

Member
2001-04-05 10:05 pm
Greece
Gray
sorry for the confusion with imaging!Of course it's one of the most important characteristics of a system!I didnt understand exactly what you meen.

Some answers:
I like to listen jazz(small combos like trio,quartet),blues and rock.I like realistic volumes and ,not always ,a little bit louder.
Sorry again,with the placement of my speakers.I mean side walls and not rear.They're 0.5m from the side walls and 2.5m from the rear.And about 2.5m between them.For imaging I think they're ok.I don't like the distance from the rear wall but I can't do something 'cause there are furniture behind them.My listening 'arm-chair' is about 4m from the speakers.And I'm always moving them a little to see differences.
Now I have a 3-way pair of speakers and a solid state amp for low freq and the 20w p-p el34 for mid and high freq.(passive xover).
Now I'm thinking to build a 2-way with an active xover.
Thats why I started a thread with a question '2-way or 3-way'.Now my speakers are with two 8 inches woofers,a mid and tweeter(transmission line).
I'm afraid that with a 2-way I'll be disapointed.From 8' woofers to 6.5' there's difference.But I haven't yet listen a good 2-way system with MTMs(which I prefer) to compare with mine.
I like the idea to build Ariel speakers.They're too efficiency and Olson said that they're getting too low.The problem is that they're difficult to build the cabinet.I also like to see some other desings before my decision.
Any other good suggestion for a desing?I like low freqs to be heard and perceptible(without a sub).I know it's difficult but I like to try.
I agree that with my el34 amp I won't be satisfied with the low freqs.But I'm a tube-aholic!I also have the solid state amp so if I'll be disappointed I can putit back.But with more efficiency speakers(now they're about 89db)maybe it'll be fine.What's your opinion?
I'm also planning in the future to build a bigger one(tube amp) with a good output xformer to get my low freqs.So maybe I'll find my happiness.
Regards
 
GAK,
tube-e, or not tube-e...that is the question...
When you're talking tubes, I'm your guy. With a few exceptions, most of the folks here (do we have any women amongst us? perhaps hiding behind one of these clever nicknames most people seem to favor?) seem to believe that gain devices come in only one flavor. Me, I like variety--I'll take chocolate *and* vanilla!
From what you describe, you're doing pretty well on speaker/listening placements. Distance from rear wall is great. Just try to keep your speakers (to the extent possible) a little more than .5m from the side walls, as first reflections from the side walls will flat kill an image. You might also consider some of those sound panels, particularly at first reflection points. Personally, I'm not real excited about the idea of spending a jillion dollars on the latest room treatments. My favored way of fixing a room is a bookshelf (or two, or three...). Just think of it, all those little diffusers working hard to fix your acoustics. And when you get done listening, you can read 'em.
Transmission lines are cool. I used to play with those a lot. They're simple (math-wise) and reliable. They're not real practical for my main system, but I'm tempted to build a pair for the video dingus, just for fun. I've always wanted to do a TL midrange, but have never taken the time to follow through. One of these days...
There is--or used to be--a TL ring out there in cyber land, somewhere. I'll see if I can dredge up an address.
Regarding Ariels: They've got a good reputation, although I've never heard them, myself. I've never built a project that someone else designed; I've always had ideas of my own that I wanted to try out, like these beasts that I'm living with now. Take a look at the designs on the Audax website. Some of those look interesting. http://www.audax.com There may be projects at other companies' web sites, but nothing else comes to mind at the moment.

Grey
 

BrocLuno

Member
2007-06-18 3:09 am
Drop on over to Silent Speakers

Google Winslow Burhoe. You'll get some good info. Along teh way, you'll get the link to silent speakers. Drop on by for a look at 2 ways with excellent low frequency capabilities. Also, you'll get a chance to download Mr. Burhoes free book on speakers.

He was part of the design team behind AR & KLH, he was EPI & Epicure, Genesis Physics, etc. His book talks about the pluses and minuses of both approaches.

I think it comes down to imaging, power handling, room size & decor, sound stage possibilities. A room with a lot of fabrics and furniture will need more push from a larger source to overcome the deficits. There is aonly so much that an 8" woofer and one tweeter can do?

Therefor folks are buying towers to get "over" the furniture. A music room with more spartan furnishings and plainer walls will have less physical air movement requirements. Might even sound good with a very small source like a top quality full range driver?
:)
 

tinitus

Ex-Moderator R.I.P.
2005-11-24 1:47 am
How about a pair of coaxial altec from "great plains audio" ... its a 15" with a small horn tweeter, and I have no clew how they manage to do that, but it is supposed work

A cheaper solution with AudioNirvana 12" with a Fostex tweeter or something might work ok too

Or maybe even a 2.5way with double 12" AudioNirvana :hot:


This EMS might be very good with a good tweeter

http://www.emspeaker.fr/home_ger.html


I suppose you see where I am heading, and there are a number of possibilities .... but drivers like PHY may over your budget

Or even this may work ok

http://www.customanalogue.com/elsinore/elsinore_index.htm

http://www.bastanis.com/ seems to be hot at the moment, but needs a lot of space

:hot:

A pair of these 10" Eminence in 2.5way with a good tweeter could be interesting

http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=290-495

You can get them from "Breitbandlautsprecher", Germany