A really big project, Vox AC30/4 clone

[pompeiisneaks]

Oh that's incredible, thanks!!! Yes I'd love the file, you sir, are a gentleman and a scholar, (unless that's offensive to you lol).

~Phil

[sluckey]

PM sent...

[pompeiisneaks]

Got it, and I also confirmed my Visio has that same option, I just didn't think to try right clicking :)

~Phil

[sluckey]

Here's a chassis layout for the AC-30.4 that is based on my AC-15 layout, only longer chassis. It will work very well with my board layout. This chassis layout has been added to the Visio file if you want to download the updated version.

[pompeiisneaks]

Got it thanks!

[pompeiisneaks]

Here's the next vid, I cover the new changes you added sluckey thanks!  Then I start trying to lay out the chassis (I've got it actually cut out right now, hopefully I'm not ordering a new one :)

https://www.youtube.com/watch?v=oO0uvCGCbN0&feature=youtu.be

~Phil

[pompeiisneaks]

Chassis setup and layout deliberations:
https://www.youtube.com/watch?v=8hg5F62de1g&feature=youtu.be

~Phil

[sluckey]

That's quite a load for those small L-brackets. I believe I would use these 3" corner braces for that job.

[pompeiisneaks]

Oh I'll see if I can find some of those that's a great idea... I didn't see anything like that at Home Depot, do they usually carry them?  Lowes?  Or am I going to have to order online?

[sluckey]

I would expect Lowes and HD to have them. Save some time and look online. I know Ace has them. I know eBay has them.

[pompeiisneaks]

Cool thanks, do you think I'll want to double those up as well, one on each side, or is one going to be enough?

~Phil

[sluckey]

Yes, one on each side. It will be much stronger and I think it will look good too.

[Willabe]

I didn't see anything like that at Home Depot, do they usually carry them?

I've bought them at Home D.

[pompeiisneaks]

Cool, thanks guys, I'll get those. 

~Phil

[pompeiisneaks]

Ok I got those brackets, and have installed them, but they'll be in my next vid, I show the sockets in this one:

https://www.youtube.com/watch?v=FPE1encm0OU

[sluckey]

I highly recommend you rotate all those 9-pin sockets 180° as shown in the layout. Otherwise the wiring between the board and the sockets is gonna be a mess.

Also, look at some of my pics of the AC-15 and wire your filaments like that.

[pompeiisneaks]

So you're saying that even though the gap in the tube is towards the board, it's easier to wire?  It seemed to make more sense to me to have that gap back where things were tighter for that reason? 

~Phil

[pompeiisneaks]

NVM, I looked at the layout and see what you mean.  The heaters are all back on that side anyway, so you can keep the heaters away from the routing, AND have the rest setup to be pretty much as you've laid it out. 

Makes sense with the picture.

~Phil

[pompeiisneaks]

Oh Sluckey, I keep wanting to ask you, where do you get those single point turret like things you're using to connect your inputs?  It seems like it also has a grounding point on the bottom?  I've not seen those before?

~Phil

[sluckey]

They are called standoff turrets and come in several styles. You find them in high quality industrial or military equipment. Mine are military surplus. You can find them on eBay...

http://www.ebay.com/itm/HARWIN-W2331-00-DOUBLE-TURRET-TAG-STAND-OFF-POST-10-AMP-10kV-Pack-of-10-Tags-/191976499132?hash=item2cb2b0e7bc:g:x64AAOSwPe1T13LC

[pompeiisneaks]

Cool, I may have to get those for my next project, those you show are in the UK and I don't know that I want to wait for international shipping ;)

I really like the idea of putting the input resistor at the pin, I remember reading that the closer that resistor is to the actual tube, the better it works.

~Phil

[pompeiisneaks]

The next video, sluckey, I've got the new braces in the first part :)

https://www.youtube.com/watch?v=63oeElR3AJ8&feature=youtu.be

~Phil

[sluckey]

That's not how I would have used those corner brackets. What I had in mind would only require two brackets and would have been stronger.

I highly recommend you rotate all those 9-pin sockets 180° as shown in the layout. Otherwise the wiring between the board and the sockets is gonna be a mess.

[pompeiisneaks]

That's not how I would have used those corner brackets. What I had in mind would only require two brackets and would have been stronger.

So what did I get wrong?  Sorry, I guess a picture may help me understand what you meant?  Doesn't adding them on both sides provide additional support and strength?  If I'm only providing support on 1/2 of the panel, then it could cause stress as the transformers create a bending force due to their weight, and then the other side that isn't supported would tend to flex and move over time? 

~Phil

[pompeiisneaks]

Oh yeah and your picture makes perfect sense, but I'm pretty sure I figured that out last week when you first explained it.  It took me a bit, but I'll rotate them around.   Edit:  And I'll use your pic there in the video to explain what I lernt :)

~Phil

[sluckey]

This is how to use those corner braces to provide more support. Since you already have 4 of them you could use one between the transformers. That would make it almost bullet proof, unless that sheet metal is so thin as to provide no support. Hopefully this pic makes sense. I'm not good with 3-D drawings.

[sluckey]

As for the tube sockets... The board layout was designed to neatly and logically accommodate a particular orientation of the sockets. I could have oriented the sockets as you want but the board would look much different. My board layout wants the sockets to be oriented the way they are shown on the diagram. Just consider the board layout and the socket layout and the front panel layout to be one optimized layout. Changing any of those three components will throw the others off.

I'm not saying mine is the only way or even the best. But a lot of time was invested to make it all work well together. And the layout has been proven to work very well. There are about a half dozen successful amp builds using this layout.

Bottom line, it doesn't have to be done like this. But we know this works.
 

[pompeiisneaks]

This is how to use those corner braces to provide more support. Since you already have 4 of them you could use one between the transformers. That would make it almost bullet proof, unless that sheet metal is so thin as to provide no support. Hopefully this pic makes sense. I'm not good with 3-D drawings.

DOH!  I see...

/facepalm.

~Phil

[pompeiisneaks]

As for the tube sockets... The board layout was designed to neatly and logically accommodate a particular orientation of the sockets. I could have oriented the sockets as you want but the board would look much different. My board layout wants the sockets to be oriented the way they are shown on the diagram. Just consider the board layout and the socket layout and the front panel layout to be one optimized layout. Changing any of those three components will throw the others off.

I'm not saying mine is the only way or even the best. But a lot of time was invested to make it all work well together. And the layout has been proven to work very well. There are about a half dozen successful amp builds using this layout.

Bottom line, it doesn't have to be done like this. But we know this works.

I totally get it, and I don't want to reinvent the wheel.  I'll spin them back around... :)

Thanks!

~Phil

[pompeiisneaks]

The next video, sluckey, at the end I fix the brackets and the sockets :)  and yet again you get a mention and thanks in the video!

https://www.youtube.com/watch?v=wFoLTTudX24

~Phil

[sluckey]

Where do you plan to mount the node A and node B filter caps?

[pompeiisneaks]

That is one of the things I'm still puzzling in my head, I know B, that's attached to the same point as the B+ on the board, so I'll attach that to there, and ground it to the grounding bus, like I've done (Similar to Doug's method).  The A one, though, I'm trying to figure out, I may be able to make it a kind of Point to Point between the pin of the rectifier and a ground, or is that not 'good'?  Do you need some distance between the rectifier and the actual cap?

If not, I'm open to suggestions.  Maybe i need to create a separate mini board to hold them?  ugh. 

Edit:  there is space for them near where the rectifier is, just nothing solid to connect them to... is it 'unsafe' to just glue them down to the chassis?

~Phil

[sluckey]

Mini board? Where would you put it? That little chassis is pretty stuffed already. It's really important that those two caps be grounded at the same point that the red/yellow wire from the PT is grounded. And that ground point needs to be near the PT and kept far away from the preamp grounds. A dual cap can is ideal for those two caps.

Just an idea... Is there room on the transformer panel to mount a cap can near the choke? Then the two choke wires would connect directly to the cap can and the PT red/yellow wire would also connect directly to the cap can. Then you would run three wires from the cap can to the main chassis. One would connect to the rectifier tube, another would connect to the board at the B node connection, and the third would connect to chassis near the rectifier tube.

Without having the chassis in hand it's kinda hard to see where to shoehorn those caps (or cap can) at this point. There was a time that you had plenty of room to put a cap can next to the rectifier as shown in the proposed layout. I wish you had done that. In fact, you could drill another noval socket hole in the space between the power tubes and the PI tube. Then shift the power tubes over. Drill out the vacated noval hole to accept the rectifier socket. Drill out the vacated rectifier socket to accept the dual cap can. Or, just leave the rectifier where it it and drill out the vacated noval hole to accept the cap can. Either way, I think this is a very logical and viable arrangement. At least give it some thought.

[pompeiisneaks]

There is still a good 2 to 3 inches of bare space from the end of the board to the edge of the chassis, but I do like the idea of mounting that one cap up by the choke too, I'll have to take a look, I may take some pics tonight and post here to let you see what's going on there.   

All great ideas, I may fall back to the cap can at the end if needed, but I already have the caps here, so if I can fit them, I'll be good. 

~Phil

[pompeiisneaks]

Oh and per your mention of the CT of the PT, should I pull that wire out and ground it right at the PT lug itself?  I was planning on running my grounding wire from there anyway, I guess I can just join that wire, and the CT at that point and run it into the chassis through the hole the other wires are in now...

[sluckey]

I don't see any advantage in that. I would prefer to connect the red/yellow lead directly to the main chassis (near the power end of the board) in a location where the negative lead of those first two caps can also be directly connected.

[pompeiisneaks]

Ok gotcha, that makes sense.  I'm hoping to actually get it all together this weekend, I finished populating the components on the board but haven't soldered yet, because I want to get the wires in first, and then solder, and then drop in after wiring up the inputs, rectifier, output to OT etc and then drop in the board...

I'll post some pics in the next day or two of the current look of things.

~Phil

[pompeiisneaks]

Here are a few pics of the board in the chassis, and I set the caps in a few ways to see where it 'may' work...

https://goo.gl/photos/8pshWArzTRsh25WW8

~Phil

[uki]

Maybe this will also be of some help as well !!

 

[sluckey]

Looks like plenty of room for the caps. I'm a bit concerned with your OT wires being so close to the VIB channel Volume pot. That's flirting with disaster. Maybe you'll get lucky.

[pompeiisneaks]

Thanks Uki!

Sluckey, yeah, I'm planning on bending them flat under the board and straight across, but I too am hoping it doesnt induce noise... The sillyness of trying to cram too much into a small chassis I guess. 

~Phil

[pompeiisneaks]

Next video is up, I start prepping the under board wires and the basic connection wires

https://www.youtube.com/watch?v=jW-ODoyXbJI

~Phil

[pompeiisneaks]

Video isn't yet done, but I've finished soldering the board and have all the wires coming off as well.  Check this album for the last 4 images, I did overview, left right and middle close ups.

https://goo.gl/photos/8pshWArzTRsh25WW8

~Phil

[pompeiisneaks]

The next video, I get to the board a bit more...

https://www.youtube.com/watch?v=1Orybin0Ezk

~Phil

[tubenit]

Steve  (Sluckey),

Can you please put this thread in ARCHIVES when it's done. This is one of the best collaborative efforts on a complicated build that I can remember on the forum.

with respect, Tubenit

[pompeiisneaks]

Thanks!  I definitely agree the collaboration with Steve on this has been stellar for me.  I think this would have been 10X harder if it wasn't for him.  I also drop notes on other things I've learned on this forum etc in the series, I love this forum for the extremely helpful nature of everyone involved.  Everyone goes out of their way to help, so long as people are trying to do what's asked ;)

~Phil

[sluckey]

Can you please put this thread in ARCHIVES when it's done.

I can do that.

[pompeiisneaks]

Next video, I cover more of how I populate the board etc.  May be boring for some, hope not :P

https://www.youtube.com/watch?v=s41MxoOc3bQ

~Phil

[sluckey]

In the future if you will use 22AWG jumpers under the board you will still have plenty of room inside the turret to put component leads. I have as many as three resistor leads in the same turret hole with an underboard jumper.

[pompeiisneaks]

Yeah, that's one of the big mistakes I made here, and I realized it after I had enough done that I didn't want to start over.  I'll make sure to use 22AWG from now on for under-board work.

Thanks,

~Phil