The Metronome

Had to share....

Bipolar Tang Band Mets almost done - they do play music now though

I'll preface this with I listened to the bipolar mets direct from my iPod into a $30 Lipai T-amp in my garage near the open garage door....

Wow, these things play magic!! The soundstage depth is measured in feet; those who posted that you can literally walk into the soundstage are not kidding! These generate way more bass than a pair of 4inchers per channel have any right to. And this is in an open garage with the nearest wall at least 5ft away. The imaging, in this specific case anyway, completely takes place behind the speaker plane. A drum kit or vocals for example are like 3ft behind the speaker plane. Very similar, and I mean -very- similar, to what I heard from the Infinity IRS Vs at PS Audio's shop in Bolder, CO. The coherency of a full-range crossover-less speaker is stunning. These are much more Beatles and Alanis Morissette than AC/DC or Halestorm though. In fact, Halestorm sounded pretty bad - harsh and confused. While they handled the bass depth well enough, even at one or two watts the system gave up lol. I switched to a pair of acoustic guitars.....OMG.

I am in love with these speakers and they aren't even in my basement yet let alone attached to my main rig. I am going to have to go through my entire music collection all over again - which is exactly the point :-D

Oh, and oh my are they elegant looking in black and bare wood......
 
Done!

Imposing, striking and elegant! These have a unique, natural way with voices, better than anything else I own. Seems to be sensitive to placement though and they require a lot of space around them....like a lot! They are at least 3 feet from any wall and they still want more space. Also placement affects imaging quite a bit - as they are, the soundstage does not extend past the outside edges of the speaker cabinets.
 

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How do I go about calculating one of these speakers for an element I just want not to lie around doing nothing? (or a kit rather, so it's the bass driver it needs to align with - my car was rear-ended into oblivion the other week, but the speakers I salvaged should still work, I hope)



Parameters for driver:


Name HG-165AeroDC-3
DC resistance Rdc 2,7 Ω
Nominal impedance ZN 3 Ω
Resonance frequency fs 49 HZ
Voice coildiameter37 mm
MechanicalQ factor Qms 7,1
ElectricalQ factor Qes 0,63
Total Q factor Qts0,58
Moving mass Mms 14,5 g
Effective piston area Sd 135 cm2
Mechanical resistance Rms 0,63 Kg/s
Compliance Cms 0,73mm/N
Force factor BL 4,4Tm
Equivalent air volume Vas 18,5 dm3
Efficiency η 0,33 %
SPL 2,83V/1m 92,0 dB
 
Pluvia 7HD

Hi all,

I want to build a Metronome for Pluvia7HD. Do you think dimensions in post 1458 (for Alpair7) are right?.

I made some simulations in LeonardAudio software, and they are very similar. This is the Pluvia response
 

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Two weeks ago I started a pair of Metronomes for Pluvia 7HD.

All panels are 15mm plywood and were cut at home with a circular saw. My shop is only 2x1.5m, but I managed to cut it. Some pictures:

Front panel with driver hole



Bottom piece. Pipe is half of a pvc fitting, epoxy glued and then secured with some sikaflex.


 

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Next is top and back pieces, in this order.

I put 10mm felt in top and back panels, fixed with wood glue.

Then I glued the second side panel and the box is closed. The hardest part is done :p
 

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I love the look of the playwood plies under where you did the roudover.

Listened to them yet?

dave


Me too :D . I usually finish edges this way, looks good and makes the varnish job easier. This birch plywood had a very good face, clean with nice grain.

I listened them and heard a strange resonance with men voices. Like a "honk" around 500hz. The box was completely empty, just the felt in back panel.

Today I put some fiber above the driver and the resonance gone. Sound is clear and vivid now, very good details and clean bass. Tomorrow I'll measure them and post the graphics.


Victor