EF86 / 1974 18-watt amp - can someone look over schem and layout?

[PharmRock]

Hello all,
I've been working on this amp for a while now, and most of it is wired up as shown in the layout.  I have a few final connections to make, otherwise it is good to go.  Was hoping a few of you guys could look this over and let me know if it all looks good, and if you see something that doesn't look right, let me know what the issue may be.

The amp is a generally based on the idea behind Sluckey's Dual Lite, however, I am keeping the tremolo channel.  Unlike the "stock" 1974, the normal channel uses an EF86 rather than a parallel 12AX7.

Some other deviations with this amp include:
1. Dr. Z Carmen Ghia tone control on the EF86 channel.  I played a CG once before and really liked the versatility of this single tone control and how it sweeps the mids.  I basically "cut and paste" the circuit into the amp (see attached Carmen Ghia tone control schematic).  I did some more digging and found that this tone circuit is also used in the EF86-driven Dr. Z StangRay as well as the Matchless Chieftan mid control (see attached schematic).
2. Pentode-Triode "morph" control on EF86 channel, as described in Merlin's book.  This seems like a simple thing to add, which I can also tweak for other purposes if I don't like it.
3. There's space on the board layout for Geezer's cathode attenuation control, but for now I have the EL84 cathodes wired normally except I'm using a huge bypass cap as recommended on 18watt.com
4. Standby switch after first filter as suggested by Merlin.
5. Safety diodes on EZ81 HVAC.
6. A couple of changes to the tremolo circuit as suggested on 18watt ("Richie's improved tremolo")....these include a 1M vs. 2M speed pot.  There's another change I made but I can't remember it.
7. 10K grid stoppers on both input grids; and single input vs Hi/Lo.
8. Fused HV-CT....I noticed a lot of the Marshall amps use this but not the 18-watter, so I added a fuse.  Figured it couldn't hurt.

I think that's about it.  Appreciate any and all comments.  Thanks for looking it over.

[PharmRock]

Updated schematic and layout...changed EL84 grid leak ground point, other minor changes.
Appreciate anyone who wants to lay their eyes on this and let me know if something doesn't look quite right.

Thanks!

[PharmRock]

All wired up and initial power-up went great.   Voltages are right where they should be, +/- 5%.  I'll need to reverse the wiring on the speed control as the way it is wired now it works in reverse, and I'll see about substituting some components in the trem oscillator circuit to widen the speed range on the tremolo.

Wasn't able to crank the amp yet as everybody is home, but it sounds pretty good.  The Carmen-Ghia tone control that I grafted in is like a thin/fat control.  So far it is sounding pretty good but we will see how it goes when I crank it up.

Can definitely tell the difference on the morph control on the EF86, but when turning the pot from triode to pentode most of the change doesn't occur until about the last 20% on the dial.  I am using a 1M audio taper push/pull pot...in the "push" position the control is bypassed. I'll play around with this for a while and see if its something I'll use, or maybe rewire it for a variable screen resistance control. 

I used a lot of shielded wire and while it was a pain, it paid off.  The amp is dead quiet, even with my fluorescent bench light on right over the chassis. 

Overall good learning experience.  More tweaking to do but it seems good for now.  This was on the more difficult side as far as getting the tube sockets wired in this chassis.  The return bend on the chassis over the controls and sockets made it a little more challenging. 

[sluckey]

Looks nice.   

[PharmRock]

Thanks! 
Some of the layout should look a bit familiar...I relied heavily on your 18-watt and Dual Lite build documents. 

[tubeswell]

... Can definitely tell the difference on the morph control on the EF86, but when turning the pot from triode to pentode most of the change doesn't occur until about the last 20% on the dial.  I am using a 1M audio taper push/pull pot...in the "push" position the control is bypassed. I'll play around with this for a while and see if its something I'll use, or maybe rewire it for a variable screen resistance control. 

IME a linear or RA taper works better here, (or wire an A-taper pot backwards, which will make the 'gain' function go from 'high-to-low' - instead of 'low-to-high')

[PharmRock]

thanks tubeswell...I have a 1M linear pot I can use, but it doesn't have a DPDT switch. But I suppose I don't need to switch it after all.  I notice that when the control is engaged and it's turned all the way to Pentode and I push in the pot to disengage the control, I can't tell any difference. 

I will say that dialing in some triode on the EF86 gives some beautiful clean tones.  pretty cool!