Speaker Oasis...Bionor

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....

The Supravox is a full range or windebander (from 50hz to 7khz and then reduced output up to 15khz). You would not want to parallel them, but add them to bass units and a tweeter.
 
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The Supravox is a full range or windebander (from 50hz to 7khz and then reduced output up to 15khz). You would not want to parallel them, but add them to bass units and a tweeter.
Yeah I noticed. Using infinite baffles allows me to think out of the box ;-)
So currently I have three 13"fullrange units with a tweeter @7-8Khz, and do not aim to have any filtering in critical frequencies, so 2 GOOD 15"units and a tweeter is far more likely for me. IME large fullrange speaker are needed to deliver the required 'weight'.

Given the results with my prototype I'd say the setup works, even when I need to extrapolate to having a second speaker in the room.
 
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...

Those companies were actually engaged in a patent war, but perhaps in a different timeline...

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....

Imho, the fascination with FC is mainly nostalgic. Given the extra costs and hassle, the performance gain is extremely small or nil.

A narrow gap, small diameter/short VC (low Xmax) and enough iron are sufficient to achieve 1.3 Tesla with ordinary materials.

This 12" is an example.1708671239846.jpeg

I'm also a firm proponent of 'spreading the load', so I'd rather use 5 decent drivers instead of a single exotic piece.
 
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I beg to differ, these guys knew what they were doing and how it should sound. I've heard direct comparisons on numerous occasions and the 'modern copies' (for in sofar that is true for someone following similar principles) almost always fail to deliver. It's not 'just' a high efficiency speaker design, plenty of those around for sure. Try read up on Dr Kurt Muller, a famous paper cone design company.
 
The Supravox is a full range or windebander (from 50hz to 7khz and then reduced output up to 15khz). You would not want to parallel them, but add them to bass units and a tweeter.
I think it's too small to convey sovereignty below 250hz. That's my opinion as I perceive it with my ears. The 285 gmf (no fieldcoil)plays e.g. in open baffle cleanly without a drop in level 85-90hz (qts 0.33 =-9db at fs 47hz). Perfect frequency to approach the bass driver e.g. 15" woofer. Above that 1" horn driver at 4khz.
 
I beg to differ, these guys knew what they were doing and how it should sound. I've heard direct comparisons on numerous occasions and the 'modern copies' (for in sofar that is true for someone following similar principles) almost always fail to deliver. It's not 'just' a high efficiency speaker design, plenty of those around for sure. Try read up on Dr Kurt Muller, a famous paper cone design company.

This is synchronicity that borders on predestination, because I wanted to touch on the subject of 'cone materials', but had to leave ;)


Here's a clue, taken from a DKM cone from the 1930s:

1708707407263.png
 
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I beg to differ, these guys knew what they were doing and how it should sound. I've heard direct comparisons on numerous occasions and the 'modern copies' (for in sofar that is true for someone following similar principles) almost always fail to deliver.


There is much to learn from the past. Due to shifts in the market(eting focus) since the 1950s, certain characteristics have been obscured, but not are not completely lost.
The optimal cone features can also be found in modern drivers, especially in budget-friendly ones.

The subtle but fundamental effects on sound quality are often ignored by people who are stuck in the 'Magico-dogmas'.
 
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Currently I'm listening to some temporary arrangement of vintage paper cone speakers containing one 8" fullrange unit per channel made in the 50-ies by Philips....they have no right to sound as good as they do, utterly ridiculous.
 
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I think it's too small to convey sovereignty below 250hz. That's my opinion as I perceive it with my ears. The 285 gmf (no fieldcoil)plays e.g. in open baffle cleanly without a drop in level 85-90hz (qts 0.33 =-9db at fs 47hz). Perfect frequency to approach the bass driver e.g. 15" woofer. Above that 1" horn driver at 4khz.

I cross the 215 over to the 15" bass just under 200Hz, and to the tweeter at 5KHz. I found that the 215 also needs some tailoring to correct for a rising frequency response that peaks around 3-4 KHz. Without this tailoring, the 215 can lack energy under 2KHz.
 
The rising response is indicative of a (more) correct representation of the input signal > low losses, due to less damping.

Here's another example (of a 15") :1708742356859.jpeg
 
I cross the 215 over to the 15" bass just under 200Hz, and to the tweeter at 5KHz. I found that the 215 also needs some tailoring to correct for a rising frequency response that peaks around 3-4 KHz. Without this tailoring, the 215 can lack energy under 2KHz.
First of all, the theory: the larger the membrane, the sooner it starts to bundle the sound (scream) and there is a strong increase in sensitivity dB/watt. That was a very general statement from me. every driver behaves slightly differently has to do with the shape of the membrane(cone)
This can also be a reason why the basket on the back is strongly illuminated by the sound from the membrane and the reflection causes the increase in this frequency range in certain cases.It is effective to dampen the basket rails from the inside with a bitumen mat.
The only thing that helps is to try it out and measure the frequency response to see if it was helpful.
There are three ways to solve this error.
1. Positioning the speakers The further away they are from the 0° axis (directly aimed at the ear), the more they roll off to the high frequencies. is the cheapest solution to the problem.

2. you take an xover and filter steeply before the sound rise begins. For me it's not a good solution and usually it's to the detriment of the sound. expensive with good components

3. Use a notch or shelf filter to smooth out the frequency range to achieve natural driver rolloff. I think this is the most elegant solution. not so expensive
 
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First of all, the theory: the larger the membrane, the sooner it starts to bundle the sound (scream) and there is a strong increase in sensitivity dB/watt. That was a very general statement from me. every driver behaves slightly differently has to do with the shape of the membrane(cone)
This can also be a reason why the basket on the back is strongly illuminated by the sound from the membrane and the reflection causes the increase in this frequency range in certain cases.It is effective to dampen the basket rails from the inside with a bitumen mat.
The only thing that helps is to try it out and measure the frequency response to see if it was helpful.
There are three ways to solve this error.
1. Positioning the speakers The further away they are from the 0° axis (directly aimed at the ear), the more they roll off to the high frequencies. is the cheapest solution to the problem.

2. you take an xover and filter steeply before the sound rise begins. For me it's not a good solution and usually it's to the detriment of the sound. expensive with good components

3. Use a notch or shelf filter to smooth out the frequency range to achieve natural driver rolloff. I think this is the most elegant solution. not so expensive

I use an inductor and resistor in parallel with the series resistor that pads the Supravox down to the level of the Woofer and tweeter, ~95db.

This has the effect of creating a slope on the pad.
 
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Bionor are yesterday’s story and have been sold. Now listening to the Euronor Jr.

F8C00344-8943-4485-8943-A1FDF3DD0639.jpeg
 
3122E310-1600-4E51-B8EF-B4A54EE1AA32.jpeg
 
Very impressive and apparently excellent condition!
Which KL drivers came with the system?
 
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Could you please say a bit more about this?
Sure.
Somewhat depending on the type/series, I describe Magico's sound signature as 'uneven order dominated'.
By this I mean highlighting details (loudness cues). The few times I listened to Magico my attention was automatically directed to specific details, while the essence (soul) of the music escaped me.

This signature is the result of R&D with a rigid focus on misleading performance goals.
High-tech synthetic materials, energy storage through excessive damping and complex filters are some of the ingredients that transform music into a sterile, lifeless presentation.

Here's a quote by (another) Klangfilm aficionado with a similar experience:

"Disappointment did not come immediately, I only found out later that this was due to the Kevlar cones. An emasculated, unexciting sound, seemingly correct, beautiful, but not catchy at all.

Then I ordered a 10" wideband speaker with silk suspensions and an 18" woofer and off we go... the path was paved with a large number of ruined speakers, including Telefunken .

But I understood one thing - the cone should only be paper with a bunch of different nuances. The best paper was from Telefunken , and from the old, pre-war ones. Anatoly Markovich Likhnitsky told how his friend in his youth worked at the Kurt Muller plant producing these unique diffusers. The recipe was secret and the raw materials were weighed in bags with metal balls."


For many people, Magico is synonymous with 'highly resolving'. For me it's equivalent to 'headache'.
 
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Sure.
Somewhat depending on the type/series, I describe Magico's sound signature as 'uneven order dominated'.
By this I mean highlighting details (loudness cues). The few times I listened to Magico my attention was automatically directed to specific details, while the essence (soul) of the music escaped me.

This signature is the result of R&D with a rigid focus on misleading performance goals.
High-tech synthetic materials, energy storage through excessive damping and complex filters are some of the ingredients that transform music into a sterile, lifeless presentation.

Here's a quote by (another) Klangfilm aficionado with a similar experience:

"Disappointment did not come immediately, I only found out later that this was due to the Kevlar cones. An emasculated, unexciting sound, seemingly correct, beautiful, but not catchy at all.

Then I ordered a 10" wideband speaker with silk suspensions and an 18" woofer and off we go... the path was paved with a large number of ruined speakers, including Telefunken .

But I understood one thing - the cone should only be paper with a bunch of different nuances. The best paper was from Telefunken , and from the old, pre-war ones. Anatoly Markovich Likhnitsky told how his friend in his youth worked at the Kurt Muller plant producing these unique diffusers. The recipe was secret and the raw materials were weighed in bags with metal balls."


For many people, Magico is synonymous with 'highly resolving'. For me it's equivalent to 'headache'.
My current speakers have (almost) no crossover…just a cap on the paper tweeter. The mid is a Lowther with Whizzer removed and a huge Alnico magnet. Woofers are all paper too and horn loaded. For speed and tone the synthetic materials need not apply.
 

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