Re: Whats Optimum when replacing 802D diaphragms with GPAs??
16 ohm GPA light diaphragms. Bill had em in stock, three weeks ago.
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
Do the GPA frams use the posts/pins to align them?
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
Quote:
Originally Posted by
RonSSS
Do the GPA frams use the posts/pins to align them?
Please, ask GPA, I don't recall precisely.
Thanks !!
Jeff Medwin ................... LOW Ohms
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
Matching diaphragms. How about the fingernail flick method? :rolleyes:
Apparently claimed to be unbeatable for tubes - see the recent Tube Tester thread.
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
— The BEST of anything is 100% intuitive, and COMES FROM THE COSMOS--- NOT from men studying it—.
Remember this: when it doesn’t yet exist, why should you WASTE YOUR TIME studying it?
Low Ohms...........
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
Quote:
Originally Posted by
mah
8ohm vs 16ohm 802 transient response.
Force on the voice coil F = number wire turns in the coil N x current i. F=Ni.
For the same power, as you increase the current and the coil wire-thickness(reducing resistance from 16ohms to 8ohms) the number of coils and the wire length will decrease in the same proportion. Thus the volume of wire remains the same and, accordingly, the coil mass is the same.
The transient driving force is therefore the same. F=Ma. F and M unchanged means cone acceleration,
a, is unchanged.
But you are missing the Bl factor, which will be more for the 16 ohms than the 8 ohms, means the 'Q' will be less (nearly as much as 75%) for the 16 ohms, means that much more a powerful motor for the 16 ohms version which also means better/more controlling power.
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
Quote:
Originally Posted by
RonSSS
Do the GPA frams use the posts/pins to align them?
Depends on the driver.
Small format 800 series drivers use fixed alignment pins.
Small format 900 series drivers use the diaphragm hub to center the assembly in a slight recess in the front plate.
Large format use a spider shim and adjustable posts.
GPA phragms are backward compatible(that means they have the holes for the alignment pins of the older 800 series drivers).
If you cannot explain it in simple terms, you do not understand it - Albert Einstein
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
Jeff
I think the only way to really answer your question, is to buy a pair of 8 ohm diaphragms and see if they sound better than your previous 16 ohm pair.
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
F=BiL
8ohm instead of 16ohm - double current I and halve wire length L and driving force F is unchanged.
BL, see here: http://www.xlrtechs.com/dbkeele.com/...%20Drivers.pdf
Re: Whats Optimum when replacing 802D diaphragms with GPAs??
Quote:
Originally Posted by
LowOhms
— The BEST of anything is 100% intuitive, and COMES FROM THE COSMOS--- NOT from men studying it—.
Remember this: when it doesn’t yet exist, why should you WASTE YOUR TIME studying it?
Low Ohms...........
Very weird, Jeff. You can't be serious, or can you? :rolleyes2:
Why waste time studying what doesn't exist? Well, it got us out of the Stone Age for one.
Leonardo Da Vinci pondered well, as have many others. Where did the SET amp come from? It didn't exist in the past.
Ideas come from the human mind - not the cosmos.