Another Diy Plate Reverb

[saint gillis]

I found this : http://www.syscompdesign.com/assets/images/appnotes/guitar-pickups.pdf

The formula says :        f = 1 / ( 2π√LC )

So the less the number of turns the higher the frequency right?
However, I don't get the relation between the number of turns and the impedance...

 

[abbey road d enfer]

I found this : http://www.syscompdesign.com/assets/images/appnotes/guitar-pickups.pdf

The formula says :        f = 1 / ( 2π√LC )

So the less the number of turns the higher the frequency right?
However, I don't get the relation between the number of turns and the impedance...

The winding is an inductor. The inductance of an inductor is proportional to the number of turns squared.
The impedance is the combination of the reactance and the resistance of the wire; both increase with teh number of turns.

 

[saint gillis]

Well that's very clear, thank you.

Do you remember which specific model of humbuckers you did use?

 

[abbey road d enfer]

I believe it was something I reapt up from a cheap Korean Les Paul copy.

 

[saint gillis]

I was minding, how loud is supposed to sound a plate reverb, I mean.. when you are sitting close to the plate with its box opened, how loud should be the sound you're listening from the plate itself?

 

[abbey road d enfer]

I was minding, how loud is supposed to sound a plate reverb, I mean.. when you are sitting close to the plate with its box opened, how loud should be the sound you're listening from the plate itself?

You may hear a very faint sound, almost like what you hear when someone listens through earbuds at high volume.

 

[saint gillis]

Thank you Abbey!

 

[saint gillis]

So I bought cheap humbuckers on ebay, with the lowest DCR I found (~3,6KΩ per winding, 7,2KΩ in series), I tried on one side of the plate, with the mic at about 3 or 4mm from the plate, wired in parallel. The sound is not bad but there is a bad resonance at 1KHz, we can hear this resonance on the plate itself. Here's the frequency response of the plate :

Can this be improved by a better tuning of the plate?

 

[abbey road d enfer]

Can this be improved by a better tuning of the plate?

You must try as much as possible to tune it mechanically and use EQ to iron out and polish the final result.
Don't forget that damping with an absorptive plate parallel to the resonating plate is quite effective at minimizing resonances.

 

[saint gillis]

So I made tests with a temporary damping element behind the plate, it didn't really change the frequency response of the plate.
I need to test different tunings.

I was just minding, can the hollow tubes constituting the frame contribute to bad resonances? And what about filling them with an expending foam? Of course it is an action with no way back...  so I'm just minding

 

[scott2000]

I was just minding, can the hollow tubes constituting the frame contribute to bad resonances? And what about filling them with an expending foam? Of course it is an action with no way back...  so I'm just minding

Wonder if you could grease the tubes or put a bag or something in them before filling????? Sorry if it's silly....I actually didn't read the entire thread.....So I'm probably thinking of something different.....

 

[abbey road d enfer]

I was just minding, can the hollow tubes constituting the frame contribute to bad resonances? And what about filling them with an expending foam? Of course it is an action with no way back...  so I'm just minding

As far as I remember, the EMT140 frame was not internally damped. Foam can't be bad anyway, but I wouldn't expect much.

 

[Gene Pink]

As far as I remember, the EMT140 frame was not internally damped. Foam can't be bad anyway, but I wouldn't expect much.

Fill with sand.

Gene