Search found 12 matches
- Thu Nov 09, 2017 12:43 am
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
You came here on a lie and to spam the forum, that is enough of an insult and rudeness. The good thing about forums is the train of posts creating a history, so what I say is as plain as the nose on your face. You will get no respect from people you lie to and troll, it is that simple. The other cl...
- Thu Nov 09, 2017 12:36 am
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
The paper referenced by Hell And Back is not hugely helpful in this context. Post 17 from Bob Brines in this thread http://www.diyaudio.com/forums/full-range/197129-metal-speaker-enclosures-bad-idea.html is, I suspect a little more relevant. well, not so. He talks of 'bell modes' which I don't thin...
- Wed Nov 08, 2017 11:41 pm
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
I'm not the rude one here. I came here looking for some info on JPW Sonatas, as vectored by Google. No-one sent me. I don't work for any company, but a few have used my help. I see now that this is not the forum I should be on, where there are no discussions making any sense, and where one is insult...
- Wed Nov 08, 2017 11:27 pm
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
These little chaps http://www.hifiandmusicsource.com/2017/10/jern-14-es-speaker-review/ are interesting. The statement in the review that "The cast iron material is apparently over 50 times better at reducing cabinet vibration than conventional wood" is useful. So I would expect a steel l...
- Wed Nov 08, 2017 5:39 pm
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
the damping factor of steel is just less than the square root of sod all. If you stick it on to 'speaker walls, all you do is increase mass and bending stiffness. There will be some damping (as you have made a new material, eg mdf/steel), so sound inside the cabinet will increase until some kind of ...
- Wed Nov 08, 2017 5:09 pm
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
no-one sent me here, I came to it by Googling 'Sonata'. I do believe that science/technology will help in suggesting a way forward. It has always served me well. Science would suggest that taking wadding out of a box would make it sound more lively, more muddled and need a little less power. That it...
- Wed Nov 08, 2017 4:39 pm
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
ah, that old 'mass damping' thing! Well, science will tell you that mass doesn't damp, it just attenuates amplitude, thus not dissipating energy. The big problem, or one of them, is getting rid of the unwanted energy, quickly, which is where damping comes in, not mass! So called 'mass dampers' are u...
- Wed Nov 08, 2017 4:11 pm
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
thanks for the offer, Paul, but I like the Sonatas, but I think I need to do some remedial damping on those boxes. Acrylic seems to work very well. Shame you are running away, Richard, I thought you might be able to throw some light on the reasons why you have chosen to incorporate certain aspects i...
- Wed Nov 08, 2017 3:52 pm
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
yes it is! Bending stiffness is proportional to Young's Modulus and the second moment of inertia, resonance frequencies are related to bending stiffness and (surface) mass. So when you add steel (of considerable mass compared to the box wood) then the resonance frequencies will go up. Basic physics,...
- Wed Nov 08, 2017 3:40 pm
- Forum: General Audio
- Topic: JPW Sonatas
- Replies: 45
- Views: 14031
Re: JPW Sonatas
not making presumptions, it's basic physics, Doc.