Need advice on this chassis layout

[markmalin]

Hi gents,


I wanted to get your advice on this.  I don't have a lot of experience laying something like this out from scratch.  Here are a few pictures - I don't have a lot of room in this chassis, so I'm trying to decide where to put the tube sockets.  My questions are:


- The pre-amp sockets are about 1 1/2" apart, like a Fender.  The EL384's about the same - I would have liked to spread them out more, but this should be OK, yes?
- The rectifier is pretty close to the PT, is there any issue with that?
- Finally, I understand how the OT and PT need to be at right angles to one another (90 degrees out of phase).  I show that in the picture, but I could squeeze some more room for the rectifier if the PT was rotated 90 degrees.  Is there any "proper" orientation for the PT with respect to the bells?  In other words, any issues with having the bells perpendicular to the chassis front/back and the iron facing the front? (obviously, if I rotate the PT 90, I need to rotate the OT 90)
- anything else that looks obviously stupid?

Thanks guys.  I always appreciate the expert input.

Humbly,
Mark.

PS - I put the board next to the chassis for perspective. The one pic shows both the main board and the power supply cap board.  With those guys end to end, there's not much more room.

[AZJimC]

Looks okay to me, and I wouldn't hesitate to rotate the transformers for more room. What's going to be the circuit?

[tubenit]

Mark,

I think you'll be OK with that.  I personally prefer the OT closer to the PT and the choke more towards the middle of the board vs. the choke between the PT and OT.  On my D'Mars ODS, I have the rectifier fairly close to the PT with no issues.  I would rather have the OT as far from the preamp tubes as possible.

Notice how close the PT and OT are towards one another.

With respect, Tubenit

[markmalin]

Looks okay to me, and I wouldn't hesitate to rotate the transformers for more room. What's going to be the circuit?

AZJimC, it's an AC30 circuit (ala Hoffman).  I'm adding a master volume and half power switch


Mark


PS - does "AZ" mean you're in Arizona?  If so, where?  (I'm in Chandler)

[markmalin]

Mark,

I think you'll be OK with that.  I personally prefer the OT closer to the PT and the choke more towards the middle of the board vs. the choke between the PT and OT.  On my D'Mars ODS, I have the rectifier fairly close to the PT with no issues.  I would rather have the OT as far from the preamp tubes as possible.

Notice how close the PT and OT are towards one another.

With respect, Tubenit

Thanks, Tubenit -  I always appreciate your input :)  I think I'll put the OT and PT next to one another and the choke on the other side like you did.  Good point being further away from the pre-amp tubes.


I see you have the pre-amp tubes spaced out further - my other amps have been like that because I have more room, but since Fender puts them pretty close I trust it will be OK.

[tubenit]

Mark,

Those are actually not my amps.   Sorry about that ............ I just grabbed photos to illustrate.

My amps have the preamp tubes spaced pretty close together.  I started a thread in ARCHIVES about tube spacing here:
http://el34world.com/Forum/index.php?topic=17406.0

The 2nd photo (middle) in the first post of that thread shows tubes incredibly close together!

So far, I've not had a significant layout problem with any of my builds & I am amazed at how quiet the amps are given my sometimes messy wiring. Occasionally, I've had to move a wire or two or use shielded wiring ....... but other then that all the layout concerns were minor (easily fixed) or non-existent.

With respect, Tubenit

[markmalin]

Mark,

Those are actually not my amps.   Sorry about that ............ I just grabbed photos to illustrate.

My amps have the preamp tubes spaced pretty close together.  I started a thread in ARCHIVES about tube spacing here:
http://el34world.com/Forum/index.php?topic=17406.0

The 2nd photo (middle) in the first post of that thread shows tubes incredibly close together!

So far, I've not had a significant layout problem with any of my builds & I am amazed at how quiet the amps are given my sometimes messy wiring. Occasionally, I've had to move a wire or two or use shielded wiring ....... but other then that all the layout concerns were minor (easily fixed) or non-existent.

With respect, Tubenit

lol.  I noticed the one looked kind of Ceriatone'ish!  It's good to know you've laid them out similarly and they work fine.


Many (MANY) years ago I was an electronics tech and when I started building amps, was kind of surprised at how neat and orderly some builders make their wiring.  Very cool looking, but I've always felt there may be too much focus on looks in some builds.  That said, I'm totally obsessive and tend to stew over bending wires a certain way because it looks neater, but try as I might, mine never turn out like those builders who go for neat right angles and such.

[tubenit]

OK, I found a chassis photo of my last build which was a D'Mars ODS with the 5879 in the OD and an active FX loop.

Note how close the rectifier tube (GZ34 or 5V4) is to the power transformer.  Very close and no issues with it at all.

Also note I really don't have very neat wiring and layouts but they've always worked OK and are very quiet at idle.

With respect, Tubenit

[markmalin]

Actually that looks quite nice.  It's a lot neater than a vintage Fender, that's for sure.


Interesting you have so much room - the chassis I chose is pretty small so I'm mounting the PT standing up, but that means I'll have to run the heater wires underneath (or fly them over) the power supply filter board, which hopefully will be OK.  In your amp you have enough room in there to route them away from the filter board.  It will be interesting to see how this pans out.  I've got one sold already (have a down payment) and the other is going to be in my "demo" stock.

[tubenit]

It has more space than any chassis I've used.  However, I've taken similar approaches to a layout in VERY cramped chassis space and it still worked.

With respect, Tubenit

[AZJimC]

AZJimC, it's an AC30 circuit (ala Hoffman).  I'm adding a master volume and half power switch


Mark


PS - does "AZ" mean you're in Arizona?  If so, where?  (I'm in Chandler)

Yes Mark. I have a place in Tucson that I seldom see, and I'm primarily staying in Dolan Springs, a tiny place between Kingman and Las Vegas, on the road toward the Grand Canyon skywalk.

[markmalin]

Yes Mark. I have a place in Tucson that I seldom see, and I'm primarily staying in Dolan Springs, a tiny place between Kingman and Las Vegas, on the road toward the Grand Canyon skywalk.

Wow, that's out there!  We've been to Tucson a couple times - nice area.  Chandler's pretty built up, but a nice enough place to live and work.

[AZJimC]

Wow, that's out there!  We've been to Tucson a couple times - nice area.  Chandler's pretty built up, but a nice enough place to live and work.

Yep, I'm an AZ native, however I lived in Oklahoma long enough to adopt southern ways, but I was raised in Safford, so I have tons of relatives and school friends all over AZ. The growth since the 70's has been amazing...not so much in Dolan though. It's literally a town where a person could come, and ask almost anyone where that long hair guitar guy is, and find out.