[Lil' Knight]

Yeah, it's made for PCB but the pins are fixed, not adjustable like the ceramic socket. Those in the link looks nice, I'll order a couple of them then

 

[BK_856er]

FYI, the Alps RK097 small pot in the current RevA BOM points to the single-channel version!  I just discovered this while organizing parts to do the casework.
 
BK
 

 

[cfcubed]

>  the Alps RK097 small pot in the current RevA BOM points to the single-channel version!
 
Ack, sorry!  I've said it privately to Mullet/Runeight during the throes of our revising the BoM, building vendor-part-specific BoMs suck  Actually, revising that BoM is one of the things that almost kept this latest GB from happening. 
Perhaps better all-around to do vendor-part-specific BoMs of this size through shared/community/wiki effort (or not do 'em & just host a "parts list").
 
I'll alert runeight to this so he changes the spreadsheet BoM.   You'll have to search for prefix "RK097122" (e.g. RK09712200MC) on Mouser or just use Panasonic Digikey alternate (cheap US shipping as discussed here).

 

[BK_856er]

Thanks, cfcubed.  And thanks also guys for all the hard work making this a reality.
 
Out of curiosity, what is the compatible range of potentiometer resistance for this design?  The small 50k pots are hard to come by!
 
Any practical consequences or considerations when deviating from the default 50k unit?
 
BK
 

 

[cfcubed]

Quote:

Thanks, cfcubed.  And thanks also guys for all the hard work making this a reality. Any practical consequences or considerations when deviating from the default 50k unit?

I'm glad you asked this CTH vol pot resistance question here.  I've used 20k & 50k input vol pots in CTHs and cannot say I hear a difference (esp any that was not possibly attributable to other differences in the builds).  My understanding is that any effect this might have is relative to the source being connected.  IOW how the source reacts to CTH's input resistance (to ground) e.g. prior stage loading.  Perhaps its not as much of a concern as the quality/balance of the pot (because common sources have no trouble driving 10k/20k/50k loads)?

 

[revolink24]

Chris, you built one of these with an RK27, right? Is the case in your Mouser BOM still a tight fit with the RK27, or is it sufficiently roomy?

As someone with only a few amp projects under my belt, I like to have ample room in my case, so I might just get a bigger case and go for standoffs.

 

[cfcubed]

>  Chris, you built one of these with an RK27, right? Is the case in your Mouser BOM still a tight fit with the RK27?
 
I've only done RK27 w/the BoM "long/longer" case, like many CTHers did, see my pics about a page back in this thread.  But someone recently was able to squeeze an RK27 in the "small" BoM case through some effort (see his post in the build Pics thread a month or so ago? - I posted there commenting on it).  I did RK097 in the "small" BoM case, as many CTHers did, like rds' pics a page or 2 back.

 

[revolink24]

Thanks, don't know how I missed that image the first time through. I have a few 50k RK27s lying around, it would be a shame not to put them to good use. The trouble I have is that the RK27s I have are all PCB mount, so I'll need to be more creative than usual in my wiring, or use a protoboard. The problem with using a protoboard is that I'm not sure it would be an ideal fit, even in the "long" Hammond case.

 

[civilmonkey]

For the socket, I picked up the generic premium gold plated $6 socket at Partsconnexcion: http://www.partsconnexion.com/socket_ceramic_prem_9pin_pcb.html
 
My question is, what is the typical insertion force?  The socket I recieved takes almost no force to put a tube in and it seems to only 'grab' the tube pins at the bottom 20% of the pins.  That is to say, I feel very little insertion resistance until the very last 3 mm or so.  Is this typical?  I have a socket saver, and getting the tube into that feels much more like I would expect, with resistance from start to finish.  My only experience with tubes is from the Little dot MK III, and it takes must less force on the socket I bought than that amp.
 
Thanks
 

 

[Mullet]

Quote:

Thanks, don't know how I missed that image the first time through. I have a few 50k RK27s lying around, it would be a shame not to put them to good use. The trouble I have is that the RK27s I have are all PCB mount, so I'll need to be more creative than usual in my wiring, or use a protoboard. The problem with using a protoboard is that I'm not sure it would be an ideal fit, even in the "long" Hammond case.
 

I wouldn't even try putting a RK27 in a smaller standard BoM case. It's tight enough as it is in the longer case. I thought all RK27s were PCB mount -- at least the one that both Tangent and Amb sell.
 
Quote:

For the socket, I picked up the generic premium gold plated $6 socket at Partsconnexcion: http://www.partsconnexion.com/socket_ceramic_prem_9pin_pcb.html
 
My question is, what is the typical insertion force?  The socket I recieved takes almost no force to put a tube in and it seems to only 'grab' the tube pins at the bottom 20% of the pins.  That is to say, I feel very little insertion resistance until the very last 3 mm or so.  Is this typical?  I have a socket saver, and getting the tube into that feels much more like I would expect, with resistance from start to finish.  My only experience with tubes is from the Little dot MK III, and it takes must less force on the socket I bought than that amp.
 
Thanks
 

I bought that ceramic pcb mountable socket that I linked to a few posts back. Insertion force seems reasonable and the grip doesn't seem to be any worse after rolling tubes about 50 to 60 times already. Like you, I bought a socket saver or two knowing that I'm going to be doing a lot more rolling for the life of this amp. I don't want to take any chances having to remove and replace a bad socket. I hear it's not a fun process.

 

[revolink24]

I wouldn't even try putting a RK27 in a smaller standard BoM case. It's tight enough as it is in the longer case. I thought all RK27s were PCB mount -- at least the one that both Tangent and Amb sell.
 

I bought that ceramic pcb mountable socket that I linked to a few posts back. Insertion force seems reasonable and the grip doesn't seem to be any worse after rolling tubes about 50 to 60 times already. Like you, I bought a socket saver or two knowing that I'm going to be doing a lot more rolling for the life of this amp. I don't want to take any chances having to remove and replace a bad socket. I hear it's not a fun process.

I'm pretty sure they are all PCB mount, I've never seen any different.

And yes, replacing sockets is a pain. I ruined a board once doing that.

 

[BK_856er]

Got my special coupling caps today.  Here's how they compare visually.  One of the GenII units is way out of spec and will need to go back.
 
BK
 

 

[Mullet]

BK~
so which ones are you going to go with? I decided Im going to stick with the Russian PIOs, which are what cfcubed used in his last build -- pictured a few posts ago.

Guys, I'm still trying to wrap my head around how ground works in this amp and why certain jacks need to be isolated and why others don't. Can someone explain in a very simplistic manner how all of this works together? The different components seem to be input ground, output ground, chassis ground, and soft ground. What about floating ground or vitual ground? My head is spinning!

 

[BK_856er]

 
Quote:

BK~
so which ones are you going to go with? I decided Im going to stick with the Russian PIOs, which are what cfcubed used in his last build -- pictured a few posts ago.
...
 

I decided to go with the Auricap.  Bit of a pain to install, but I think it worked out OK.  Needed to trim down the wire diameter to fit the board holes, cut to length, position, etc.
 
BK
 

 
 

 

[Mullet]

BK~ Looks great!
 
I have a few goodies that I would like to offer up to anyone involved in the group buy. First and foremost, I'm offering up 2 or 3 perf boards. They might or might not come with grommets because the holes will be different sizes and I'm not sure what I have will match. They will be in silver and black. The black needs to be stripped of paint and re-painted or possibly not. Whoever PMs me first gets one of them for just S&H. The second goodie that I have are four 12AU7 type tubes. All NOS. One RCA 5814A, one RCA 6189, one Sylvania 5963, and one Sylvania 6189. I'm offering them all up for $10 plus a few bucks for shipping and handling. Finally, I have a matched pair of NOS Siemens ECC82 Silver/Chrome plates that I'm going to be putting up in the For Sale forums if I have no takers. I figure I'd offer them up here first. They are best described as very analytical or accurate. Awesome with AKG701s and Jazz or Classical. I've only popped each of them in once to test them out. I'm going to be asking $140 shipped for the pair or $70 for one. I'm thinking this is a great deal being that they go for way more on Fleabay. They really are one of the best 12AU7s. The only pic I have for now is of the Siemens chrome plates. So here goes...