New Fischer & Fischer Audio 670 Speakers : Made Out Of SLATE..


show me a piano or a slate violin..?
as well as glass, aluminum - all this makes the sound clinically sterile ... The body must vibrate - the materials of the body must be close to the materials of musical instruments - you will get the right tone


Id be curious to hear them. Slate, like cast iron or granite, is an intriguing material for speakers because of its resonance control and rigidity.

My question was directed @serjio  who seems to think a speaker is a violin.

@perkri I watched a bunch of Real World Audio's videos on Youtube. He's obsessed with single driver speakers using active cabinets (voigt pipes, folded voigt pipes, transmission lines).


Real World Audio actually uses the violin analogy to describe active cabinets. Violins are made of the lightest, most rigid wood because you want the cabinet to resonate to amplify the sound. Wood with a natural grain is preferred but plywood is acceptable and much cheaper. MDF is bad because it has no natural grain.  These cabinets are inherently harder to build because you have to fine tune the cabinet by slowly removing material and using bracing. 

Slate is an intriguing choice because it has laminar structure like wood but is rigid and hard like stone. So is the Fischer speaker using a dead cabinet (MDF/granite) or an active cabinet (wood)? 

The first time I decided to get my speakers off the thick carpet, I used Slate Slabs and the change was stunning


Ive build a bunch of various horn loaded speakers, ranging from 6’ tall, 300ltr double horns w 8” drivers to small 3” Baby Labs along with some voigt pipes. Yes, I like full range drivers also :)

Rigidity is kind of key in ensuring that cabinet resonances are kept to a minimum. 

3/4” Baltic birch has been my material of choice as it is lighter than MDF and provides an equal, if not better, resonance control than MDF. The big horns I build weigh about 120lbs. Don’t want to think about what they would weigh if I had built them out of MDF.

I built both my kids Baby Labs for their rooms. One pair was built out of cheap ply, and the other out of MDF which was thicker than the ply. I also added some bracing to that enclosure. The stiffer, thicker MDF speakers sounds better than cheap plywood. Better clarity and bass control.

 A speaker is not like a musical instrument in that you want the box to provide any sound - in most cases… The speaker driver itself is the instrument, and it needs to be put in an enclosure so it gets to do what it’s supposed to. It’s my opinion, that the enclosure is there to aid the driver in doing it’s job. It should help to move the sound waves without imparting any additional tone which could smear the sound from the driver 

Wood is comparatively inexpensive, and easy to work with. Materials like slate, cast iron, aluminium, concrete or fibreglass, all require very specialised tools and processes.

Currently, I’m working in a pair of coax speakers that I am researching having enclosures that are made of gray cast iron. But, expensive to have done if one doesn’t have connections to help with that.

Would be such an interesting experiment to have identical enclosures of significantly different materials so first hand A/B comparisons could be done.   


The Acora Audio Speakers use Solid-Granite for their speaker cabinets and many Reviewers pick them as the Closest to "Live Music" they have heard.. No Matter the Type of Speakers Too ! So I'm Shocked more Speaker Companies are not using Granite and the BEST "SLATE" for their Speaker Cabinets !🤔🤔



They are coming out with their New Next Generation Slate Speakers right now! 

They show you how slate cabinets are made in this video ! 😃😎

Besides Acora in granite there are also speakers made of concrete like Rauna.

Wilson, Magico, Rockport and others also has pretty stiff boxes made of different materials. 

OCD Mikey will be at Capitol Audio Fest with Fischer and Fischer 770.1 with Playback Designs DAC and Server, powered by 150w Nat mono Tubes.  He is promising a top sounding room to compete with the $1m rigs.  

Capitol Audio Fest Nov 10-12, 2023