Speaker Oasis...Bionor

[Audiophile Bill]

My take home message is; build it in sections to control vibrations and add strength, the wood type does matter, and thickness of the baffle surface itself matters (greatly) too...3 mm somehow was an optimum for me on large baffles.
Just see how Klangfilm made them, that was not done for transport reasons I reckon....O how I wish to be able to speak with the key designer of those days....

Yeah also would love to meet / chat with these guys.

 

[MarcelNL]

I wish for a 'reunion' with the Western electric designers and those for Klangfilm, it might bring us to a situation where we could combine the utterly stunning dynamics of WE and realism of Klangfilm in one system...

 

[bonzo75]

I wish for a 'reunion' with the Western electric designers and those for Klangfilm, it might bring us to a situation where we could combine the utterly stunning dynamics of WE and realism of Klangfilm in one system...

Do you go to Munich, you get to hear a different WE each year

 

[MarcelNL]

Do you go to Munich, you get to hear a different WE each year

I plan to attend the next HE....it was on the agenda for the last few years but somehow each and every time a business trip popped up for that very week.

Now recently there is a bit of an issue with travel....

 

[bonzo75]

I plan to attend the next HE....it was on the agenda for the last few years but somehow each and every time a business trip popped up for that very week.

Now recently there is a bit of an issue with travel....

Ok, since 2014 I go there to listen to a different one each time.

 

[ddk]

Hi David,
What did you learn specifically in the baffle building process?

cheers.

Pretty much what Marcel suggested. The wood matters and has a direct effect on the sound, you can mostly kill everything. Baltic Birch is terrible for this purpose and even most solid woods are too damp to sound right, you need a certain amount of resonance and life. Please keep in mind that most of my tests were done with various Siemens Klangfilm systems.

david

 

[MarcelNL]

I have a hunch that alpine 'Hoch Fichte' (think it is high grown pine in English) does great, the ultra slow growing stuff Stradivarius used, and is in use until today for musical instruments...now only to find large enough sections to work with, I have a source for pieces up to 90cm...

 

[Audiophile Bill]

Pretty much what Marcel suggested. The wood matters and has a direct effect on the sound, you can mostly kill everything. Baltic Birch is terrible for this purpose and even most solid woods are too damp to sound right, you need a certain amount of resonance and life. Please keep in mind that most of my tests were done with various Siemens Klangfilm systems.

david

Which wood did you land on for your Bionor cabs out of interest?

 

[MarcelNL]

nothing as of yet, as I'm currently using coated painters paper , a bit like making a model glider plane, using rice paper with nitrocellulose lacquer to tighten the paper .

all the experiments are ongoing...I have like 16 months or so to kill before I can build the final versions so I'm taking my time to really experiment with pretty much every detail.
Location of the 'feet' when using OB also matters, I made the mistake to put them too far to each side, what Klangfilm did was pretty much spot on I know now.

 

[ddk]

I have a hunch that alpine 'Hoch Fichte' does great, the stuff Stradivarius used, and is in use until today for musical instruments...now only to find large enough sections to work with, I have a source for pieces up to 90cm...

Pine can be good!

Which wood did you land on for your Bionor cabs out of interest?

They're original Bionor baffles and I have no idea what they used. They're not at all dead when you wrap on them but they don't resonate either. Interestingly you're never ever aware of this baffle in the sound but I heard the ones I made.

david

 

[Audiophile Bill]

nothing as of yet, as I'm currently using coated painters paper , a bit like making a model glider plane, using rice paper with nitrocellulose lacquer to tighten the paper .

all the experiments are ongoing...I have like 16 months or so to kill before I can build the final versions so I'm taking my time to really experiment with pretty much every detail.
Location of the 'feet' when using OB also matters, I made the mistake to put them too far to each side, what Klangfilm did was pretty much spot on I know now.

To allow the baffle to resonate and quickly get rid of the stored energy?

 

[MarcelNL]

To allow the baffle to resonate and quickly get rid of the stored energy?

yep, that is the current theory

 

[MarcelNL]

BTW; anyone see the Dior 21 fashion show showcasing some inflated Euronor speakers? (Youtube has the video)

 

[MarcelNL]

To allow the baffle to resonate and quickly get rid of the stored energy?

also, to allow the sound wave front to 'push off' of something fairly solid that does not absorb all energy....wave propagation IMO is a key issue in speaker design that is not very well understood/researched.

 

[ddk]

Location of the 'feet' when using OB also matters, I made the mistake to put them too far to each side, what Klangfilm did was pretty much spot on I know now.

That's very interesting, I control some nuances of the sound by varying the width and depth of base on the turntables we manufacture, didn't realize baffle legs have the same functionality.

BTW; anyone see the Dior 21 fashion show showcasing some inflated Euronor speakers? (Youtube has the video)

Yes, it's funny to see what's cool now.

david

 

[MarcelNL]

IMO the feet are nothing less/similar to /than grounding points in an electrical circuit, with a TT surely the location of the feet makes a big difference?

(we experimented using rubber bands, huge O rings basically, around a TT platter and found that the location of the bands made quite a difference on the voicing of the TT (Garrard)

 

[dcathro]

IME the baffles can either be too thin or too thick, too thick does more damage than too thin.
the Goodman's Axioms you mean, yeah well, sigh...unobtanium and all that.
Next stage is likely a field coil, but that is quite the project...

Hi Marcel,

The Supravox 215 EXC field coil is very similar sounding to the Goodmans Axiom 80, and can be found second hand for a reasonable price.

Cheers

David

 

[MarcelNL]

Hi Marcel,

The Supravox 215 EXC field coil is very similar sounding to the Goodmans Axiom 80, and can be found second hand for a reasonable price.

Cheers

David

Thanks for that pointer, there is however one drawback, I'm using three 13"woofers and am more likely to go towards two 15"

 

[LL21]

Thanks for that pointer, there is however one drawback, I'm using three 13"woofers and am more likely to go towards two 15"

Interesting...why are you leaning towards 2 x 15 vs 3 x 13?

 

[MarcelNL]

I was referring to the Supravox 215 FC that was mentioned, I'd need a boatload of those to arrive at the same surface area. IMO you can only replace surface area by more surface area. Without doing the math, at which I'm terrible, I know the design would become inefficient...perhaps in the a smaller Euronor Junior setup, with a speaker geometry as Dior 'used' in their show last fall.

Going FC likely means $$$$, so three chassis per channel is probably a bit rich, therefore it probably makes sense to go 2"larger diameter and skip one chassis rather than use like 5 chassis per channel....