Ah, excellent. Thanks Barry.Originally Posted by Barry
Ah, excellent. Thanks Barry.
Fount Master & Moderator
Location: Essex
Posts: 32,042
I'm openingabottleofwine.
That equation was specific to David's case of his head amp presenting a load of 1000 Ohm.
In general the formula for two resistors, R1 and R2 in parallel is:
R1*R2/(R1 + R2)
So if R1 is the impedance of the head amp (call it Rh) and Rc is the value you want the cartridge to 'see', then the value of the additional loading resistor (RL), wired in parallel with the head amp (or SUT) is
RL = Rc/(1 - Rc/Rh).
Maths lesson over for today!
Barry
That equation was specific to David's case of his head amp presenting a load of 1000 Ohm.
In general the formula for two resistors, R1 and R2 in parallel is:
R1*R2/(R1 + R2)
So if R1 is the impedance of the head amp (call it Rh) and Rc is the value you want the cartridge to 'see', then the value of the additional loading resistor (RL), wired in parallel with the head amp (or SUT) is
RL = Rc/(1 - Rc/Rh).
Maths lesson over for today!Thanks mate. I'll try it out.
Ok, so using your equation, my phonostage presents 1k so for the desired 470R loading I like I'd need 626R
Have I done that right?
Fount Master & Moderator
Location: Essex
Posts: 32,042
I'm openingabottleofwine.
No, the value should be 887 Ohm:
470/(1 - 470/1000) = 470/0.53 = 886.8 Ohm.
Barry
Super Moderator
Location: W Lothian
Posts: 99,005
I'm Grant.
i got it right
Regards,
Grant.... ؠ ......Don't be such a big girl's blouse
I've said it before and I'll say it again: democracy simply-doesn't-work.... ..... ...... ...... ................... ..... ..... ..... ..... .....
FIIO K7 BT, M11 PLUS, BTR7, KA5 - OPPO BDP-103D - PANASONIC UB450 - PANASONIC 4K ULTRA HD TV - PIXEL 6 - AVANTREE LR BLUETOOTH - 2* X600 SOUNDCORE - HEADPHONES INCLUDE, FIIO, NURAPHONES', FOCAL, OPPO, BOSE, CAMBRIDGE, BOWER & WILKINS, DEVIALET, MARSHALL, SONY, MITCHELL & JOHNSTON - 2*ZBOOK'S- MERCURY BD ROM, ROON, QOBUZ, TIDAL, PLEX, CYBERLINK, JRIVER - MULTI HDD'S -
Oh my god! There's nothing wrong with the bidet is there?
“Nothing discloses real character like the use of power. It is easy for the weak to be gentle. Most people can bear adversity. But if you wish to know what a man really is, give him power. This is the supreme test. It is the glory of Lincoln that, having almost absolute power, he never abused it, except on the side of mercy".
“You see these dictators on their pedestals, surrounded by the bayonets of their soldiers and the truncheons of their police ... yet in their hearts there is unspoken fear. They are afraid of words and thoughts: words spoken abroad, thoughts stirring at home -- all the more powerful because forbidden -- terrify them. A little mouse of thought appears in the room, and even the mightiest potentates are thrown into panic.”
"You don't have free will. You have the appearance of free will.”
“There's a war out there, old friend. A world war. And it's not about who's got the most bullets. It's about who controls the information. What we see and hear, how we work, what we think... it's all about the information!”
***SMILE, BE HAPPY***
honestly, I have that numerical dyslexia I think. I should get checked out.
Member
Location: Hartlepool
Posts: 93
I'm John.
I'd sell the Ayre!
Super Moderator
Location: W Lothian
Posts: 99,005
I'm Grant.
try 2000 amp and 300 desired
Regards,
Grant
I've said it before and I'll say it again: democracy simply-doesn't-work.... ..... ...... ...... ................... ..... ..... ..... ..... .....
FIIO K7 BT, M11 PLUS, BTR7, KA5 - OPPO BDP-103D - PANASONIC UB450 - PANASONIC 4K ULTRA HD TV - PIXEL 6 - AVANTREE LR BLUETOOTH - 2* X600 SOUNDCORE - HEADPHONES INCLUDE, FIIO, NURAPHONES', FOCAL, OPPO, BOSE, CAMBRIDGE, BOWER & WILKINS, DEVIALET, MARSHALL, SONY, MITCHELL & JOHNSTON - 2*ZBOOK'S- MERCURY BD ROM, ROON, QOBUZ, TIDAL, PLEX, CYBERLINK, JRIVER - MULTI HDD'S -
Oh my god! There's nothing wrong with the bidet is there?
“Nothing discloses real character like the use of power. It is easy for the weak to be gentle. Most people can bear adversity. But if you wish to know what a man really is, give him power. This is the supreme test. It is the glory of Lincoln that, having almost absolute power, he never abused it, except on the side of mercy".
“You see these dictators on their pedestals, surrounded by the bayonets of their soldiers and the truncheons of their police ... yet in their hearts there is unspoken fear. They are afraid of words and thoughts: words spoken abroad, thoughts stirring at home -- all the more powerful because forbidden -- terrify them. A little mouse of thought appears in the room, and even the mightiest potentates are thrown into panic.”
"You don't have free will. You have the appearance of free will.”
“There's a war out there, old friend. A world war. And it's not about who's got the most bullets. It's about who controls the information. What we see and hear, how we work, what we think... it's all about the information!”
***SMILE, BE HAPPY***
Posting Permissions
Reply With Quote