Please help with META42 values
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TimG

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I am currently in the process of building my first META42 amp. My first amp of any kind for that matter.

The amp will be for use with the line out on my panasonic PCDP and with Senn. HD580's

I wanted to run by the values I have come up with for the resistors, to make sure I have chosen correctly. THe more I read into the discussions here, the more I doubt my selections.

R1 = 750
R2 = 158k
R3 = 2.55k
R4 = 10k
R5 = 6.8k
R6 = 680k
R7 = 93.1
R8-R9 = jumper

This is to work with the Alps Blue Pot. 100k
The amp is wall powered only by a regulated PS. Elpac #WM113TT

For Capacitors
C2 and C3 = 1000uf 25V

DId I pick the correct values?

Thanks very much for your time and patience.

Tim
 
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antness

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If R2 is the resistor i think it is, you want a higher value than 158K go for about 1M
 
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JMT

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I agree with antness. R2 should be at least 2x the resistance of your pot. 500K or 1M would work great.
 
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antness

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also i just want to remind you that with that PS you do not use the TLE2426
 
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Fixup

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Here is the value for my recently finished mini META:

POT: 10K
C1: 0.1uF
R1: 0
R2: 100K
R3: 249
R4: 2.49K
R5: 1K
R6: 100K
R7: 49.9
R8: 49.9
R9: 0

Gain of 11 and sounds great!
 
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Gariver

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Fixup:

What caps are you using? Most likely, you are not using all of the caps in your tiny META42 (C1, C2, C3, C4). So which ones are you using? What are the values?

I imagine that your resistor selection is designed to work with regular earbuds such as Sennheiser MX-500 (or Etys). Is this correct?

For the META42, I am searching for a R3 to R6 selection that can be used with a wide variety of headphones and earbuds. I am still undecided on the final selection.
 
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Fixup

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I don't use any optional caps. The film inputs are Panasonic P-series polypropylene and the power filters are Panasonic FS series electrolytic 470uF.
The resistors are set for a gain of 11, that's good for all headphones from lo-impedance Grado 60 to hi-impedance Sennheiser HD580/600.
 
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Gariver

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Thanks, fixup! I will now order some Vishay RN55s from Mouser.com with your resistor values. That's exactly what I wanted: A group of resistors for both high and low impedance headphones (or earbuds)! I just wasn't sure of my selections!
 
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