Bookshelf with Pioneer B20 and a tweeter

[imagios]

Hello Guys,
I know there is a lot of threads on the Pioneer B20 but I can´t find here a nice bookshelf drawing.
I look forward to build a small bookshelf, ok as small as a 8" can be, for the weekend cottage of my girlfriend. It should be a "cheap" project, with decent quality.
I have choosen the "famous" Pioneer B20 as a basis and help him out with a nice tweeter, it could even be more expensive. Lets say I could spend 100$ for all of the components. That gives a nice budged for a decent tweeter.

Does any one has a link for such a project? Any recommendation on the design, tweeter and crossover?

Thanks,
Daniel

PS: unfortunatelly most of the http://www.zillaspeak.com/ link that a lot of threads are reffering to is broken

 

[Godzilla]

Hi, you can go here...

Single Driver Website

I think the B20 works really well in a small sealed box as small as .75 up to 1.5 cubic foot. I'd be happy to help you with the crossover but first you must choose the tweeter you want to use.

ZillaSpeak.com is not maintained anymore. Please visit www.ZillaAudio.com

Thanks!
Zilla


PS. you can also look here:

Pioneer B20 (BOFU) full range driver plus piezo tweeter

http://www.zillaaudio.com/pioneerb20-3cubox.htm

 

[imagios]

Well thanks for the info,
what do you think of the combination with this tweeter:
Eminence APT-80 Super Tweeter
Eminence APT-80 Super Tweeter with 80° Conical Horn | Parts-Express.com

Do you have by any chance the dimension of the 0,75 cubic foot encloasure?

 

[imagios]

Thinking of it right now I would like to cross over to the Tweeter at about 2,5KHz, do you think this is a good idea?

Would use a 30 Ohm rezistor with a 4uF cap, would this be adequate?

 

[Racket Scientist]

That tweeter is much more efficient than the Pioneer is - you'll need to pad it down significantly. I might go with something more like this:
Dayton DC28FST-8 1-1/8" Silk Dome Truncated Shielded Tweeter | Parts-Express.com
which will probably mate better a be a bit smoother as well as easier on the pocketbook.

 

[Racket Scientist]

You might also consider a true mid-woofer rather than the Pioneer if you plan to cross over that low.

 

[imagios]

Thanks for the info, you got a point.

Looking at the performance of the Pioneer, he has a significant gab at 2,5Khz and after 5KHz he is quite unstable, so 5KHz is the max. I would like him to go.

If I would use your tweeter and would like to cross over at 5KHz what crossover parts would you recommend?
Thanks
Daniel

 

[el`Ol]

A bookshelf usually can't be directed towards the listener, so a high-crossed 8"er can give dispersion problems. This tweeter would have the capability to dynamically keep up with an 8"er with lower crossover:
Tweeter à dôme Sica LP90.28/N92TW (8 ohm)
The Tangband W5-1880 would be a candidate for a 5 kHz crossover solution, but unfortunately more expensive than the Pioneer, the high excursion raises the amount of magnetic material needed.

 

[imagios]

The bookshelf would be in a 12m2 room so I would not be affraid of direction towards the listener
As the room is small and the space is limited I need to stay with the bookshelf.

 

[sreten]

Hi,

There are loads of better options out there that what you are considering
for compact speakers, and a 6.5" bass / mid will give you far more choice,
even if they have to vented in a box similar sized to an 8" sealed.

Pay particular attention to Zaphs driver tests for choosing drivers.

rgds, sreten.


undefinition
Zaph|Audio
FRD Consortium tools guide
RJB Audio Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
Humble Homemade Hifi
Click below to go to
Quarter Wavelength Loudspeaker Design
The Frugal-Horns Site -- High Performance, Low Cost DIY Horn Designs
Linkwitz Lab - Loudspeaker Design
Music and Design

 

[imagios]

thanks for the links there really are some greath pieces for nice prices

 

[imagios]

To Godzilla: where would you cross over the pioneer?

 

[badman]

I have good results with some 25L semi-aperiodic box (30Hz tuning), and a supertweeter (Dayton ND20FB-4 IIRC) mounted coaxially. The small box gives it a bump that manages the baffle step reasonably well in my room, and the damped slot vents (down firing) worked well to hint at the deeper stuff without demanding massive excursion.

 

[Godzilla]

>>> There are loads of better options out there...

No doubt many will feel that way about any speaker. I've built lots of speakers as a hobby over the years and always seem to enjoy the B20 plus a supertweeter. It's not the best speaker but it's not fatiguing, it's forgiving of poor quality cds and not very expensive to build. IMO it's better than the $1000 pair of B&Ws I own... others may think they suck.

I 'crossover' the B20s with a piezo tweeter using a .47uf capacitor and an 8 ohm resistor OR a 1uf capacitor and a 20 ohm resistor. Both sound good to me but i prefer the .47uf + 8 ohm (less treble hash imo). It's not perfect but it's very good. For an easy, good sounding DIY speaker project i suggest the B20 plus the tweeter of your choice. Play with capacitor values on the tweeters until you find the sound you like best. Try domes, cones and horns... play around and see what sounds best TO YOU. Everyone can have their own personal favorite B20 configuration. But the character of the B20 is what dominates the overall sound and for many that's a good thing.

Zilla

 

[imagios]

To Badman: you would not by any chance have a drawing or photo?

To Godzilla, yes that I can agree on that
at what Hz cuts your solution the B20 off?

 

[motosapien]

>>> There are loads of better options out there...

No doubt many will feel that way about any speaker. I've built lots of speakers as a hobby over the years and always seem to enjoy the B20 plus a supertweeter. It's not the best speaker but it's not fatiguing, it's forgiving of poor quality cds and not very expensive to build. IMO it's better than the $1000 pair of B&Ws I own... others may think they suck.

I 'crossover' the B20s with a piezo tweeter using a .47uf capacitor and an 8 ohm resistor OR a 1uf capacitor and a 20 ohm resistor. Both sound good to me but i prefer the .47uf + 8 ohm (less treble hash imo). It's not perfect but it's very good. For an easy, good sounding DIY speaker project i suggest the B20 plus the tweeter of your choice. Play with capacitor values on the tweeters until you find the sound you like best. Try domes, cones and horns... play around and see what sounds best TO YOU. Everyone can have their own personal favorite B20 configuration. But the character of the B20 is what dominates the overall sound and for many that's a good thing.

Zilla

I'd like to build a pair of those for my daughter. Been cruising the pawn shops looking for a good used stereo receiver in the 30 watt range. Basically I pick them up to see how heavy they are. So far no luck but at some point I'll come across an old denon or harmon kardon.

The speakers you describe sound like they would be perfect for her.

 

[sreten]

Hi,

No way is it remotely better than $1000 worth of B&W's, that is just silly.

The mid and treble end of most twin cone budget drivers sucks big time,
I accept the Pioneer for the genre avoids the worst excesses of the type,
by being rolled of in the treble end, and good if you must have an 8"
budget twin cone driver, a supertweeter is relatively easy to add.

But its a big driver with a Vas and Qts needing big boxes, if that is not
a problem far enough enough, but for many it is, especially portability.

e.g. the Overnight Sensation MTM - undefinition
would be great with even the smallest quality HK reciever.

rgds, sreten.

 

[badman]

Hi,

No way is it remotely better than $1000 worth of B&W's, that is just silly.

Sheesh. Not like any of those who like B20s/fullrange with supertweeters have ever heard $1,000 B&Ws....

Case in point, B20s in a proper box can sound very nice indeed, and are just a different set of compromises than are the B&Ws. Many of us prefer them. Your response lacks both respect and credibility.

Attached are pics of my standmounts, and the slot porting method. The back panel attached over the strips.

 

[Godzilla]

Those came out great badman! You get bass and a non finiky speaker placement all in a small package. Subwoofer optional... enjoy the music!
Zilla

 

[imagios]

Nice picture I might do a similar thing but definately with the tweeter.

Anymone suggestion the dimension for such box? Badman, would you have a plan for yours?