Valab 23 step volume attenuator

ZacharyP · 7297

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Offline ZacharyP

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Reply #15 on: April 07, 2015, 05:10:29 PM
There is some confusion about what is needed, or appropriate for a replacement of the Crack pot. 

Of course it needs to be log/audio taper, discrete resistors are preferable over SMDs (for some reason they don't sound as good) and finally it is best to be 100k Ohms like the stock pot.  So you don't mess with a fine design you just get refined small steps.

I just wanted to get this all together.  If the OP puts this info into the first post I'll happily delete this post.


Hope the first post looks better Grainger!



Offline Grainger49

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Reply #16 on: April 08, 2015, 12:37:30 AM
Yes, Zachary, I deleted my post now, it adds nothing to the thread.  You now have the information where all new Crack 'heads can easily find it.  I only want newbies to find the information easily.  Your thread is ideal for that.
« Last Edit: April 08, 2015, 04:45:19 AM by Grainger49 »



Offline Bill Epstein

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Reply #17 on: April 08, 2015, 04:23:29 AM
This one?

http://www.ebay.com/itm/281654181885

The one Allan Marcus linked has been my main system volume control for years after sounding just as Zachary described about the one he used compared to TKD and PEC pots. Highly recommended but the SMDs make it quite finicky to wire up; order two!

I have one of those that Zachary is posting about on the shelf awaiting installation in my much delayed Aikido 6SN7 build.

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Offline ZacharyP

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Reply #18 on: April 10, 2015, 08:35:36 PM
The one Allan Marcus linked has been my main system volume control for years after sounding just as Zachary described about the one he used compared to TKD and PEC pots. Highly recommended but the SMDs make it quite finicky to wire up; order two!

I have one of those that Zachary is posting about on the shelf awaiting installation in my much delayed Aikido 6SN7 build.

Ooh, my "mentor" to this DIY audio thing (addiction, who we kidding) wants me to come visit, he has the parts and chassis for an Aikido board and a SET EL84 amp that he wants me to build.  Let me know how your build goes!



Offline AllanMarcus

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Reply #19 on: April 24, 2015, 07:08:31 PM
got my pot. wow, i wasn't ready for the size. cool! Now I gotta borrow a friend's Dremel to enlarge the holes. For those that haven't seen this pot...

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fmarcusfamily.info%2Fimages%2Fpot.jpeg&hash=3aa3c85206c76a6895d8cea2176f135ce2e5d876)



I have a question about soldering the wires. There is already some solder in the holes of the pot I got. What's the best way to deal with that? I was thinking holding a tinned wire against the hole, touch the iron tip to the wire to heat it, then hopefully it will slowly insert into the hole.

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Offline ZacharyP

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Reply #20 on: April 25, 2015, 02:59:55 AM
Could you post pics of the solder filled holes?

Thanks,

ZP



Offline AllanMarcus

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Reply #21 on: April 25, 2015, 04:14:28 AM
Could you post pics of the solder filled holes?

Thanks,

ZP

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fmarcusfamily.info%2Fimages%2FPot-side.jpeg&hash=03f3283ad00b4c4b5b6463ae7ce2dd4ddd3c7521)

Maybe the wires don't go in the holes on this one, but are soldered between the two "dots" next to the G/out/in?

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Offline Grainger49

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Reply #22 on: April 25, 2015, 04:23:54 AM
I think what you suggested is a good idea.  Go with that then after the wires are in add a tiny touch of your solder.  I always count to three after the solder is all liquid then remove the iron.



Offline ZacharyP

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Reply #23 on: April 25, 2015, 05:23:05 AM
That is different than mine looked.  If you run into any trouble post here and I will post pics of mine and help you trouble shoot it. :)



Offline AllanMarcus

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Reply #24 on: April 26, 2015, 11:23:28 AM
Umm, I looked at the eBay listing again, and the pot I purchased is supposed to be new

http://www.ebay.com/itm/Valab-23-Step-Ladder-Type-Attenuator-Potentiometer-100K-Log-Stereo-/281654181885?

It's pretty clear it isn't, so I sent a message to the seller. Anyone work with "vintage_audio_lab" on eBay before?

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Offline JamieMcC

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Reply #25 on: April 26, 2015, 11:45:30 AM
I have brought a number of items off of them in the past and have always been happy with the quality of the items I have received.

Shoot for the moon if you miss you will still be amongst the stars!


Offline AllanMarcus

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Reply #26 on: April 26, 2015, 12:10:56 PM
I have brought a number of items off of them in the past and have always been happy with the quality of the items I have received.

Good news. Hopefully they will make it right. I think I'm right in noting the pot isn't new. I assume a new one would not have old solder on the connections.

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Offline Grainger49

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Reply #27 on: April 26, 2015, 02:42:07 PM
I have bought a few things from them and have had no problems.  As many Bottleheads who have used them I would expect you get a good response from them.



Offline AllanMarcus

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Reply #28 on: April 27, 2015, 05:43:25 AM
I heard back, and true to form, very good customer service.
Quote
You got a used potentiometer, not a new one.
My assistant take potentiometer I used for my sample preamp.
He do not check product carefully enough.
They gave me a full refund and said I could keep the pot. I left good feedback for them

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Offline ZacharyP

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Reply #29 on: April 27, 2015, 06:45:33 AM
I heard back, and true to form, very good customer service.They gave me a full refund and said I could keep the pot. I left good feedback for them

They are a great little outfit, aren't they?  Glad it all went well.