Stereo HiFi speakers without subwoofer

[fabiomayo]

Dear all, I am new here and have been reading your thorough discussions for a while.
I would like to ask your help for choosing a speaker/system design.
I am moving and will build a complete system from scratch. I chose to use the projects by Rod Elliott (ESP @ Elliott Sound Products - The Audio Pages (Main Index)) because they are simple and PCBs are provided. I built a phono preamp P06 for my father a while ago and we love it.

Anyway, the idea is to have a good sounding stereo system to listen to vinyl records and CDs on my small living room. I would prefer not to include a subwoofer and as such I am hoping for a good 3-way design that's not too expensive (of course!! ). Since I know nothing about it I would like to find a "tried and true" design. So far I've seen those three:
(1) Zaph|Audio - ZDT3.5, about U$290 for the drivers alone, tower design;
(2) Parts Express DIY Project, monkey-coffin style, cheap at U$110 for the drivers;
(3) My New Speaker Box Project - Part 1, stand mounted, more expensive drivers.

I would build the cabinets myself, provided accurate plans are available. The system would be bi-amped (low and mid-highs separated through a preamp active crossover and mid-highs separated through a passive crossover inside the speaker cabinets).

This is the main sketch for the system:
http://i15.photobucket.com/albums/a3...eoHiFi_peq.jpg

Sorry for the long post. I appreciate any advice or critique on the chosen circuits.

Best regards.

[Andersonix]

Have you thought of building Zaph's 'L18' in a sealed box (and later adding subs in a separate box underneath, if needed)?

[a.wayne]

I would go for 3 way vented, what size room and what are your expectations, critical listen, spl , etc ....

[mdocod]

I would say skip option #2 there. I see lots of glaring problems with that design. My opinion of goldwood drivers is that they are often worth even less than their already low price points, though I'm sure they probably make some that are decent. I wouldn't call that design any more "proven" than anything I could mash up in about an hour in simulation (actually, that is probably worse than what I could mash up). Notice the use of a pre-made x-over... Which means that the x-over does nothing to deal with the natural peaks and dips and breakup nodes of the various drivers in a "proper" manner.

Option 3 does not include any plans for a passive x-over. Not that one couldn't be modeled but the driver selections IMO are really geared towards at least a bi-amp setup to allow the use of a very low x-over point between the low and mid range units. If you wanted a "finished" proven design, then option 3 is only half way there unless you intend to go tri-amp.

If it were me personally and trying to get the budget down a bit, I'd do a 3.5 way similar to zaphs (use the zaph as inspiration) but reduce material costs by using Dayton aluminum cone 8" drivers instead of the 7" reference drivers. For the money they are hard to beat. That would cut driver costs by ~$100. The x-over between the dome mid and dome tweeter could probably go nearly un-changed (only different padding for each of these drivers) from zaphs design. The lower x-over would have to be reworked and modeled up.

Eric

[fabiomayo]

Hi, all.
Thank you all very much for your replies. I haven't noticed the L18 until now, Andersonix. I like it, but I was thinking about something more "self-contained", hence the three-way speakers and no sub. It is an option, however, if budget gets tighter and your idea of adding subs underneath them is quite good. I'll look into that.

The room is about 23 x 10 feet (7 x 3 meters), but the "listening area" is about 10 x 10 feet (3 x 3 meters). It has lots of open spaces, i.e. corridor, opening to kitchen, big door to balcony. As such, it is not the best room as far as acoustics go.
The system is intended for quality casual listening of entry-level sources (Rega RP1 turntable, run of the mill CD player for now). And of course, I hope it is fun to build!

Thanks for your suggestion, Eric. I will look into those 8" drivers. BTW, I am planning on bi-amping the system (low / mid+hi).

In theory, I would like efficient speakers just so I don't push the amplifiers too far. Having said that, my expectations are for a low volume listening (apartment).

[mdocod]

If you're planning on bi-amping, that actually reduces the complexities of the x-over quite heavily. I can go over with you what I would eliminate and change to convert the zaph 3.5 to a bi-amp speaker if interested. Integration with different woofers (the aluminum drivers instead) should be no problem if bi-amping because you can adjust your active x-over and levels to flatten everything out pretty easily.

If efficiency is really important though, hard to beat a 3-way built around a pro-sound 15-18" bass driver, ~6" mid, and a compression horn. I'd put the compression horn in a wave guide. It would have to be miced and padded accordingly though. Personally I would call such a build way in excess for apartment speakers unless you have lots of concrete between you and your neighbors.

[AllenB]

Originally Posted by mdocod

Personally I would call such a build way in excess for apartment speakers unless you have lots of concrete between you and your neighbors.

It may not be a bad choice. The good thermal performance of this configuration is beneficial even at lower levels, and I'd think the close walls of an apartment would amount to a good reason to want some directivity control.

[wahab]

Two way speakers shoulds be enough for the intended purpose.

Just make sur to use a proved design.

As a clue i use two ways speakers that give very good accuracy
even in the basses despite a reduced size.
Speakers are 8" + 11/8" , size ( WHD) is 240 x 404 x 244 mm.

[sreten]

Hi,

2) and 3) are a very bad idea, both clueless, but in different ways.

1) is good if it suits your requirements and space, it is possible a
2-way floorstander would be more cost effective, but FWIW IMO
there is not much wrong with the ZDT3.5 if its what you want.

iGiven your ambitions for active bass/mid and passive mid treble
i.e. two channel active bi-amping, I'd say Zaph's design is the
best choice if you know how to convert it to that arrangement.

rgds, sreten.

[tvrgeek]

Look at the Thor subs on Linkawitz site. This concept can easily be built as a standard 3 way. The peerless can work up to maybe 150 if in the same cabinet, making the choice of the mid-base easier. Still in the active crossover range and then passive on the top two. You may think you are rolling off too soon with that small box, well in room they do very well.