Valab 23 step volume attenuator

[ZacharyP]

Edit:  Installed the Valab attenuator after reading JamieMcC's thread ( http://bottlehead.com/smf/index.php?topic=5284.msg50963#msg50963 ).

If you're also looking to swap the stock pot out for an upgrade you must make sure it's log/audio taper, discrete resistors are preferable to SMD type, and you should stick to the same value as the stock pot; 100k ohms

 

[AllanMarcus]

Today I am wiring up the Valab to the rest of the crack, but my overly cautious, perfectionist mind won't let me solder the wires in until I understand exactly what I am doing.  I've read a couple older threads on this forum about installing the Valab but just to be safe I was hoping someone could provide me with simple step by step directions, or link me to a post with a thorough explanation.

I appreciate anyone taking the time to read this.  Have a good day!

i'm interested too. Can you post pics and a link to exactly what you purchased?

 

[Mordicai]

I'm pretty sure its pretty straight forward, but it would have been nice is he had followed up the post. Maybe things didn't work out.

 

[ZacharyP]

Sorry, figured it out.  I'll post pics sometime tonight or tmrw.

I just followed the pics I eventually found posted on head-fi, if I can find the link again I will share.

You can find the attenuator for sale on eBay.

 

[ZacharyP]

Snapped a couple quick pics of the underside if this helps.

 

[AllanMarcus]

Is this the one you got?

http://www.ebay.com/itm/281647229684

 

[ZacharyP]

Is this the one you got?

http://www.ebay.com/itm/281647229684

No, this one but 100k value

http://m.ebay.com/itm/301568448140?nav=SEARCH

 

[AllanMarcus]

No, this one but 100k value

http://m.ebay.com/itm/301568448140?nav=SEARCH

This one?

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

 

[ZacharyP]

Yes

 

[Mordicai]

Thanks Zachary for the photo. Ive had the attenuator for about six months. Bought it for the Crack, saved it for Steromour, and need to put it in. Do you think you heard a difference?

 

[ZacharyP]

Oh yeah.  It could all be in my head of course  .  To me everything just seems clearer, more balanced and smooth.  I was slightly worried about the number of steps but 23 is more than enough!

 

[Mordicai]

This weeks project if I can force myself to turn it off!

 

[AllanMarcus]

I just ordered one for me! I will never know the difference, though, as it will go into my first build.

I just painted the top plate, and will do multiple coats and sanding to get a good gloss finish. I did manage to finish the crack phones, except for the cable, and they sound pretty good. I think I like my DT-770's better, but it's amazing what some mods can do for those inexpensive monoprice phones. Makes me wonder why they don't sell a "hi-fi" version of them for $89.

 

[grausch]

I installed the VALab after listening to the stock pot for a while. My stock pot had no issues and I am not sure that the sound is any better with the VALab.

That being said, it was my first mod and it is a great way to build confidence for doing other mods. Only issue with the attentuator is its physical size. If you look at JamieMcC's thread (http://bottlehead.com/smf/index.php?topic=5284.msg50963#msg50963) you will notice how he needed to mount his speedball boards with it in place.

 

[Mordicai]

Thats why its been sitting o my work bench for six months. The stock pot seems to work just fine. I think Id rather spend my time putting in some better caps like I have with the Stereomour.

 

[ZacharyP]

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!

 

[Grainger49]

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.

 

[amioutaline?]

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.

 

[ZacharyP]

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!

 

[AllanMarcus]

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...

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.