Best OB Full Range Purist Design No BSC or Filter

I am looking for the best sounding 20 to 22cm full range driver for a purist OB design for a floor standing speaker in the living room with no subwoofer. I understand that FR drivers usually need a BSC or filter to adjust for dips and peaks but the goal here is purity of signal chain.

Wire from amplifier to back of the speaker terminals and that's all.

I have read ZaphAudio's review pages but those are 5+ years old.

Which threads here would discuss the best FR 20cm drivers for such a project?

Would getting the DX4 EX4 Lowther's be the best choice here?

I will be building a prototype using much cheaper drivers first as proof of concept.

TIA!
 
What's the meaning of 'purist' so ?
If it is intended in its original form, it should be referred as
a system that adds nothing, nor it subtracts ...

The simple math behind OB tells that you have to balance the loss
of low frequencies with an increase in gain of those low freq.

You can make it actively or passively, but it is correct that
the speakers have to be two at least : you cannot move lots of air
and in the meantime play a cymbal, as some inter-modulation occurs
when the cone tries to reproduce both.
 

robert92062

Member
2012-01-16 10:48 pm
When I decided to try ob some folks told me I would be sorry for using cheap speakers,but I went ahead and built a folded wing using some Radio shack 40-1272 after hearing them I knew that this was a sound I wanted so I stepped up to the Betsy from Wild Burro and I have loved every minute with them. Still a very reasonable priced speaker.
 

ultrakaz

Member
2004-10-20 11:32 pm
Would getting the DX4 EX4 Lowther's be the best choice here?

No, that would be one of the worst choice(s).

Do a search on Altec 755a. I recall reading something about some guy doing something quite similar to what you want to do.

For a modern driver I would lean towards the Visaton B200 on a big baffle; ie 3' x 5' or something like that. If you can go bigger than 20cm, the PHY 12" would be a good choice. Or if even bigger, 15" Altec Biflex.
 
Everyone appears to think I want bass. I don't. You guys do. I am OK with limited bass. Thus I am OK with an OB design.

This is going to be one driver on a plank of wood.
Regardless of what driver you try, SPL on a simple plank of wood will roll off below 200 Hz. Regardless of what kind of music you hear, music with bass rolled off from 200 Hz will sound anemic. Are you prepared for that?

Rudolf
 

ticovski

Member
2002-07-11 7:46 pm
I am looking for the best sounding 20 to 22cm full range driver for a purist OB design for a floor standing speaker in the living room with no subwoofer. I understand that FR drivers usually need a BSC or filter to adjust for dips and peaks but the goal here is purity of signal chain.

Maybe Phy-hp or Fertin?

I will be building a prototype using much cheaper drivers first as proof of concept.
TIA!

Supravox 215 S BICONE ?
 
"Regardless of what driver you try, SPL on a simple plank of wood will roll off below 200 Hz. Regardless of what kind of music you hear, music with bass rolled off from 200 Hz will sound anemic. Are you prepared for that?"
I have written thrice that I am happy with the limitations of an OB, and this includes the rolloff below 200hz such as currently exists with the $1 driver mounted on a piece of cardboard in my living room that I am listening to R.E.M. on at this moment.

For the third time, these concerns are YOURS. I don't want what you want. I don't want bass.

You think it sounds anemic. I do not.

============================

jimbro, einric, ultrakaz, pico and ticovski - thank you all for the solid usable recommendations!
 
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jimbro, einric, ultrakaz, pico and ticovski - thank you all for the solid usable recommendations!
You're welcome...actually it's something that happened to me.
Indeed, often the shoe-size boxes with little drivers are welcomed !
It's a matter of giving the right attribution to each instrument in space, i.e. it has to be recognizable to be at the right place.
Bombing the bass of course it doesn't help, and it worsens .
So the mind itself might prefer not to hear any bass instead of a wrong one.
The soft decay in freq response on the low bass of any driver without any box might be more appealing; the solution consists in eliminating the ...;):p
 
Indeed, often the shoe-size boxes with little drivers are welcomed !
It's a matter of giving the right attribution to each instrument in space, i.e. it has to be recognizable to be at the right place.
Bombing the bass of course it doesn't help, and it worsens.

The loud full spectrum repro is for my head fi rig, and I spent a few decades as a DJ so bass does not have the appeal that it does to most.

What I want is to hear the sound as when I was in the back room of a club talking with friends with the band playing on stage, and the bass was usually missing. The standing waves of 15 hz that I would set up were for the corners and in the stairwells.

I also have very nearby (6 feet) neighbours on 3 sides so to be considerate no bass extension is wanted.

My hearing is gone above 13.5khz so ultra extension isn't needed either. Thus full range drivers with an Fs of 90-150 are perfect for me. It's just a matter of selecting one with a minimal breakup node or peakiness from 2k to 6k.