Zen ZV9 Question

[Albertone]

Hi!
I am building a Zen ZV9, so I am searching for a couple of 25k potentiometers. Nelson says in his pdf that all resistors are 1/4 W, so should I use a 1/4 watt potentiometer or can I use a pot with more power??

 

[Nelson Pass]

You can use any pot you like - it isn't going to conduct
signal, and of course you can substitute resistor values
until you get what you want, which is an output DC
voltage at 1/2 the regulated rail.

😎

 

[Albertone]

What an honor!! The Mighty Nelson Pass in person!!!
Forgive me for the idiot question, but I'm a newbie....
Thank you very much.. and thank you for this great amplifier!!!

 

[Albertone]

Sorry Nelson, but can I use this pot with the default resistor values?? (I absolutely don't want to make any error in the building!!)

Potentiometer

 

[Alain Dupont]

Albertone,

http://www.digikey.com

Ref# 490-2979-ND

Murata TRIMPOT CERM 25K OHM 12TRN TOP 250mW

http://rocky.digikey.com/WebLib/Murata/Web Data/PV37 series.pdf

As a good example...

Alain.

 

[Albertone]

So the one I selected won't work?? Because I'd like to mount a stereo one...

 

[Alain Dupont]

Albertone,

I can't reach the one you did choose, the link is not working

could you please give the reference ?

Alain.

 

[Albertone]

Of course! Here's the Digikey part number:

KKA2531S28-ND

 

[Alain Dupont]

Albertone,

Are we speaking of P1 the pot in the lower left of the schematic ex Fig #6

The point is each channel has to be adjusted separately
and the current in this pot is < 0.75 mA

so why not ; but quite overkill....
{plus to find the sweet pot of the second channel you'll have to add a separate
pot on one channel, not really easy}

And a 12, 15 or 20 turns will be much more easy to adjust !!!

Alain.

 

[Albertone]

Yes the P1... Isn't it the pot for adjusting the audio volume?
So... if i mount one per channel, I have to adjust the volume for each channel separately, right?? This doesn't look very nice....

 

[Babowana]

No.

P1 is to adjust the output DC voltage, which is to be 1/2 the regulated V.
As Papa already said . . . post#2 . . .

 

[Albertone]

Sorry.. I didn't read well... But how can I adjust the audio volume if P1 doesn't do this??

 

[paulb]

You need a preamplifier, or just a volume control potentiometer in front of the ZV9.

 

[Albertone]

Ok, now I understand how the circuit works!! Thank you!! 😀

 

[Babowana]

Ok, now I understand

😀

You must be a guy who always sleep in the classroom . . .
Don't make too much watermark on books 😀