Amp wiring and layout question.

[Phil_S]

Ah! To the crux of it. Sure, but you know, every action has it's consequences. I suggest making a layout drawing and showing it to us. It can be a simple sketch. Many of us see things when presented with the whole picture, things not obvious in parts.

[matt h]

(deleted)

[Zippy]

FWIW, some designs are known to be layout sensitive, others not so much.

Listen and learn before you reinvent the wheel.

Or... buy a bunch o' parts and go for it!

[Phil_S]

When you start to draw the thing, you'll find out why the board goes between the sockets and the control panel. If you have patience, you'll find another way to do it. You'll go through all sorts of socket rotations and other things. Remember to consider the filament supply, which is something that always gets in the way and why sockets tend to all have a single orientation.

[xtian]

Don't miss Hiwatt layouts! So beautiful.

[img::]http://chambonino.com/mac/mac6.jpg[/img]

[Alan0354]

Thanks guys. I started this post because I was afraid that there is some reason with the sound to have a board in between that make the leads longer after I look at quite a few guts shots in the last two days. I thought some sort of coupling and maybe positive feedback is at work to create the desirable sound. Then I read the other post on OT and sounds like the main concern is oscillation and coupling. That case, I think I can handle the layout.

I already built two amps with no board, just circuit strips. I have no oscillation issue. I just want to ask here to make sure I am not missing something.

I drawn so many layouts on papers to optimize the lead length and to have room in case of adding more circuits already, I think I am good.

Yes, Mark, I am using circuit strips for components. I did not explain that detail in my OP, instead just said components from tube to potentiometers. I have ordered and received 20 of the 7 posts terminal strips, I have a 100W big soldering iron to solder the strips onto the chassis. I managed to have the preamp tubes to be about 2" from the potentiometers to minimize the leads in my layout. Now I feel a lot better going forward.

Thanks

[martin manning]

Here is a non-traditional Express layout: https://tubeamparchive.com/viewtopic.ph ... highlight=
I believe that the traditional guitar amp layout with an eyelet or turret board between the controls and the tube sockets was initially used to speed production (lowering cost) and for serviceability. Credit Leo Fender for that. The type of construction you are talking about ("point-to-point") was common in the 1950's and '60's, even in RF devices like AM and FM radios and television sets.

[M Fowler]

I built an Express following Martin's layout and it is one of my favorite Express amps with no noise or issues. (Well the presonance did give me some problems).

I also built one of rjguitars.net PCB Express and that was another great Express with no noise or issues.

[1986AM]

This is my first post here. I enjoy building amps and don't post because I still have a lot to learn. I've put my foot in my mouth more than once over at the Hoffman forums.
Since Alan was asking about placing the preamp tubes closer to the controls I figured I'd post a picture of my first attempt at a channel switching amp. I placed the preamp tubes close to the tone controls. The amp has been changed a lot over the last few months trying to get it voiced right, avoid switching pops, and get rid of heater hum. I eventually changed the preamp heaters to DC to get it to go away. The hum was never out of control, but more than I would like. The way I ran the heater wires seemed like it was a straight up AC injection into the preamp. I think It could have been avoided by using a more traditional layout and some shielded wire.

Thanks to everyone here, I really enjoy cruising the forum.

[Ken Moon]

Another nice layout scheme is a PTP layout scheme with tag strips that was refined by the Gothik group over at AX84, that they call the Gothik Ring.

It does a good job of not only keeping wiring short, but keeps each local current loop to/from that stage's B+ filter cap small and local. This feature is what distinguishes this layout from some other PTP schemes.

Here are some examples, and much more info is available at AX84:

[img:800:598]http://i1100.photobucket.com/albums/g40 ... 55bc62.jpg[/img]
[img750]http://tinymaninside.net/Audio_Designs/ ... 0_17_1.png[/img]
[img750]http://tinymaninside.net/Audio_Designs/ ... 0_15_1.png[/img]


[img:800:600]https://sphotos-b.xx.fbcdn.net/hphotos- ... 8662_n.jpg[/img]

[Stevem]

Can we talk some about the phase change that takes place as the signal goes thru coupling cap after coupling cap?

[Zippy]

Another nice layout scheme is a PTP layout scheme with tag strips that was refined by the Gothik group over at AX84, that they call the Gothik Ring.

It does a good job of not only keeping wiring short, but keeps each local current loop to/from that stage's B+ filter cap small and local. This feature is what distinguishes this layout from some other PTP schemes.

That looks very similar to Hoffman's layout of power supply caps - I've long referred to it as a "distributed" cap layout. I like it.

[Reeltarded]

(Well the presonance did give me some problems)

Best control that works in most cases, EVER!!

The above layout is inspirational. It's way beyond crazy, but it looks fantastic.

[es345]

Can we talk some about the phase change that takes place as the signal goes thru coupling cap after coupling cap?

> have a look here http://www.electronics-tutorials.ws/fil ... ter_3.html

[Zippy]

Another nice layout scheme is a PTP layout scheme with tag strips that was refined by the Gothik group over at AX84, that they call the Gothik Ring.

It does a good job of not only keeping wiring short, but keeps each local current loop to/from that stage's B+ filter cap small and local. This feature is what distinguishes this layout from some other PTP schemes.

That looks very similar to Hoffman's layout of power supply caps - I've long referred to it as a "distributed" cap layout. I like it.

[img494]http://el34world.com/Hoffman/images/Dscn0294.jpg[/img]