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Old 28th October 2008, 10:23 PM   #821
vonfilm is offline vonfilm  United States
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bubba177,
Is this the mono attenuator pair you purchased on ebay?


http://cgi.ebay.com/Stepped-Attenuat...3286.m20.l1116
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Old 29th October 2008, 02:40 AM   #822
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Default mono 25k stepped attenuators on ebay

take a look at ebay Item number: 300269147273 from seller 8audio

here is a link:

http://cgi.ebay.com/25K-24-Step-Ladd...713.m153.l1262
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Old 29th October 2008, 03:55 PM   #823
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This guy seems to only carry stereo ones, but he was recommended by multiple people on HeadFi - he makes his stepped attenuators with SMD resistors

http://stores.ebay.com/Vintage-Audio...QQftidZ2QQtZkm
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Old 29th October 2008, 04:53 PM   #824
dviswa is offline dviswa  United States
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Dear Mr. Pass, ZM,

I know B4 is coming, but I have a Full range OB with Woofer assist project going, so perhaps with a little help from you I can do a P-P protoboard version. Here are a couple of questions:

In post #161 ZM posted one of your drawings. That drawing did not identify the 3 Rs and 3 Cs, but ZM did in his hand drawn picture in post #153, so I will use the same. What is the formula for computing R1, R2, R3 and C1, C2, C3 in ZM's HP filter. I am assuming the same formula can be used to compute the values for the LP filter as well. ZM presented some values which are good for crossing over into a tweeter not into a full range.

What is the insertion loss of this configuration? that might determine if I will need a gain stage.

What is the slope of this filter?

ZM, I did not understand why you tied the outputs of the 2 filters together with 10K at point 6. Please explain.

Thanks a lot,
Dinesh
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Old 29th October 2008, 05:06 PM   #825
Zen Mod is offline Zen Mod  Serbia
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Quote:
Originally posted by dviswa
.......

ZM, I did not understand why you tied the outputs of the 2 filters together with 10K at point 6. Please explain.

Thanks a lot,
Dinesh

ZM is , as usual , not responsible for anything

I just digged old Papa's drawings , saved on my PC form old Pass site - previous to hacking several months ago ;

I hope that Papa will answer you ; if not - I'll try later ( tonight)
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my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa... by Mighty ZM
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Old 29th October 2008, 06:03 PM   #826
vonfilm is offline vonfilm  United States
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Default B1 Digi-Key Order

I am getting ready to order parts from Digi-Key for my B1. I would appreciate recommendations if there are better choices.

R1 1Ohm 3W P1.0W-3BK-ND 5% Metal Film
R2 10K 1/4W P10.0KCACT-ND 1% Metal Film
R3 "" "
R4 15K 1/4W CMF15.0KQFCT-ND 1% Metal Film
R100 1M 1/4W P1.00MCACT-ND 1% Metal Film
R200 " "
R101 " "
R201 " "
R103 " "
R203 " "
R102 1K 1/4W P1.00KCACT-ND 1% Metal Film
R104 " "
R204 " "
R105 221K CMF221KQFCT-ND 1% Metal Film
R205 " "
C100 1uF BC2076-ND Metallized Polypropylene Film
C200 " "
C3 " "
C101 10uF EF2106-ND Metal Poly Cap
C201 " "
C1 15,000uF P6890-ND Electrolytic
C2 " "
D1 Diode 1N914BCT-ND
D2 ??? Not sure what Digi-Key part would be appropriate

Matching JFETS from Pass Labs -DIY

P100 25 K Mono Stepped Attenuators form 8Audio.com on Ebay
P200 " "
4 way switch GH7102-ND Grayhill Rotary Switch

C101, C102 Also ordered Axon 10uF Metallized Polypropylene from Zalytron

I am ordering enough parts for 2 B1's. One will be with the Pass Labs-DIY board and the other will be Zen Mods 9volt version built point to point or dead bug style.

I am sure that you can tell I am new at this. Any thoughts or recomendations will be appreciated.
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Old 29th October 2008, 07:35 PM   #827
dviswa is offline dviswa  United States
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Quote:
Originally posted by Zen Mod

ZM is , as usual , not responsible for anything
Sneaky you...
But, papa did not do it...

Quote:
Originally posted by Zen Mod

I just digged old Papa's drawings , saved on my PC form old Pass site - previous to hacking several months ago ;
Aha... the secret comes out. I was totally impressed that you had all that stuff stashed away since 80s. Not so, huh...

Quote:
Originally posted by Zen Mod

I hope that Papa will answer you ; if not - I'll try later ( tonight)
I hope papa answers....
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Old 29th October 2008, 07:39 PM   #828
Zen Mod is offline Zen Mod  Serbia
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Quote:
Originally posted by dviswa

.......


Aha... the secret comes out. I was totally impressed that you had all that stuff stashed away since 80s. Not so, huh...



.......
naah ...... don't tell anyone ........ I was Papa's secret agent , for East Europe ........... in my age of 13 .............




__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa... by Mighty ZM
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Old 29th October 2008, 11:02 PM   #829
Vix is offline Vix  Yugoslavia
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Quote:
Originally posted by Zen Mod


naah ...... don't tell anyone ........ I was Papa's secret agent , for East Europe ........... in my age of 13 .............





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Old 30th October 2008, 09:32 AM   #830
Tolu is offline Tolu  Germany
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Quote:
Originally posted by Nelson Pass


There is a B3 coming, and it has voltage gain.


Before ?
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