DR. Sluckey AB763vibrolite build..... Line out?

[Toxophilite]

Hello all
I'm new here and I look forward to the discussion I'm hoping to engenderjavascript:void(0);

I'm building a vibrolux 5F11 using and existing Electrohome Hifi chassis as a bassis
It has a good power transformer with a seperate filiment tap for the 12AX7 (hum control..neat)
An 8 ohm nice sized under the chassis mounted output transformer
And a usable tube compliment of 2 6V6GT 5Y3GT 12AT7(driver) 12AX7 preamp and 6AV6 (preamp)

It also has an interesting feature of what looks like an adjustable bias for the 6V6 run off the 2 220k resistors on the grids to separate leads of a trim pot ..I believe their run to ground through the pot. The cathodes also hooks to the 220K resistors via 470 ohm resistors

It shares the exact same power amp section and 12AX7 hum balance control of a similar vintage Electrohome PA300 that I previously converted to a guitar amp by rewiring the inputs and preamp section. I will attempt to put the schematic of that up and a picture of the current amp but it was my attempts to do that on my ancient computer which seems to have foiled my earlier posting attempts.)

Anywho
i have a couple of questions
I mostly like 5F11 over the deluxe because of the nice tremelo and the negatice feedback with flatter response, more clean headroom and brighter sound. I am however not concerned with keeping it stock..I mostly want a cool amp that suits my needs and sound (mostly clean)

-I've read that the 6AV6 is basically half a 12AX7. Can I use it to run the tremelo, thus freeing up one side of the 12AX7 for potentially another channel, or gain stage.

-Is there a problem with leaving the hum balance control on the 12AX7 preamp?

-I guess if I want to have the neat vibrolux tremelo I likely can't keep the kind of neat adjustable 6V6 bias feature, Yes or No ?

- I wanted to put the standard fender tone stack (bass mid treble) in hooked the way it usually is with the 1 meg volume control
I know this has more insertion loss. I don't mind losing some potential distortion but will this make my amp too quiet?

the Pa300 schematic which shares the power amp section and preamp hum balance


I've built another vibrolux, and it sounds nice though it hums some at maximum volume..THis increased when I did the jiggery pokery to create the proper negative voltage for the tremelo as there is no bias tap. I used a tried and true formula I found on this site and the tremelo works great
i might post about it too

Thanks in advance

[Toxophilite]

Anyone have tips on the phtot process..flickr URLs don't seem to work
Thanks

[terminalgs]

-I've read that the 6AV6 is basically half a 12AX7. Can I use it to run the tremelo, thus freeing up one side of the 12AX7 for potentially another channel, or gain stage.

yes.

-Is there a problem with leaving the hum balance control on the 12AX7 preamp?

do you mean the second filament winding with a hum trim pot?  I'd use that as-is. no problem with that setup.  Fender would have done that if trim pots and extra secondary windings were free 

- I wanted to put the standard fender tone stack (bass mid treble) in hooked the way it usually is with the 1 meg volume control
I know this has more insertion loss. I don't mind losing some potential distortion but will this make my amp too quiet?

I would suspect you'd want another gain stage after a B/M/T tone stack.  you can always put a voltage divider after that make-up gain stage and before the gain stage that precedes the cathodyne.  that arrangement would probably work well with your clean headroom goal.

your img attempts fail b/c those links are images, they aren't url's to actual images.  here's how to make the urls work:

http://www.flickr.com/photos/68271311@N08/11793776143/
the Pa300 schematic which shares the power amp section and preamp hum balance
http://www.flickr.com/photos/68271311@N08/11793869763/

I'm not sure how to make the flickr pic appear here...

[Toxophilite]

here's a picture of the somewhat gutted chassis
And the electrohome PA300 schematic which has an identical power amp section and preamp hum balance setup

[Toxophilite]

Thanks for the response, That helps a lot and gives me the green light on some things.
By voltage divider I imagine you mean potentiometer/master volume right?
I remember my engineer brother-in-law calling potentiometers voltage dividers

I managed to get the photos up by squishing them a little.

Am I right in assuming I'll have to do away with the trim pot on the grid and cathode (is it bias) of the 6V6s to incorporate the vibrolux tremelo circuit?

[Toxophilite]

And another stupid question!
I have a GZ34 rectifier, the output transformer on this unit looks pretty big (certainly bigger than the 2 6V6 5U4gb organ output transformer I have kicking around.
Could I make this into a AA964 blackface Princeton and achieve more clean volume?..especially into a tasty old JBL.
I tried the GZ34 in it very briefly and I seem to get the right sort of voltages
Is this transformer roulette?
And how do I tell what older transformers can handle?
The power tranny in this one is marked LK 588-1
The Output  tranny is marked LK 560 -2

[ac427v]

Wow, It looks like you found a great base amp to start with! The GZ34 rectifier doesn't use any more heater current than the 5Y3GT so it should not stress the power transformer...But, can the power supply capacitors handle the higher voltage from the new rectifier?

I found that my homebrew Princeton AA964 was a great learning experience...but it was too quiet. My 5E3 was twice as loud with similar voltages. Others have said that is typical of the non reverb Princeton. It really needs the third triode gain provided by the reverb mixing stage of the reverb version. I tried boosting gain by changing the first two stage cathode resistors and plates but that only created ugly distortion at volume. YMMV. I am making a Hoffman turret board to convert to an AB763 without reverb but with the bias vary tremelo. I have done that circuit before and love the cleans and the sound of that trem. The nonreverb 6V6 version of AB763 makes current demands similar to your original Electrohome design so it may be an option if you don't mind making a board to replace your point-to-point Electrohome. I'll be curious to see what you try (first)

[floyd]

This forum is  much better than the others.. isn't it ?

[sluckey]

Am I right in assuming I'll have to do away with the trim pot on the grid and cathode (is it bias) of the 6V6s to incorporate the vibrolux tremelo circuit?

Yes. Your amp currently uses a fancy cathode bias circuit in the PA. You'll need to convert to fixed bias and build a negative bias supply. Since your PT has no bias tap you'll have to get the AC input from the HT winding. Just copy a Princeton bias supply circuit.

Could I make this into a AA964 blackface Princeton and achieve more clean volume?..

Sure. I can't say that it will have more clean volume though.

I tried the GZ34 in it very briefly and I seem to get the right sort of voltages
Is this transformer roulette?

Perfectly safe for the transformer.

And how do I tell what older transformers can handle?
The power tranny in this one is marked LK 588-1

Chasing that number on the PT will likely lead you down a blind alley. The best way to get an idea of what that PT can handle is to measure secondary voltages and analyze the circuit it is currently in.

[Toxophilite]

For the Power transformer
I get 433 volts at the rectifier plates with the amp on and a 5Y3 plugged in

Is there a way I can test the power handling of an otherwise unknown output transformer?

For fun here's a picture of the Electrohome PA300 conversion I did a couple years back and have used at many many shows as my stereo echo amp (I run the wet sound from my RE-150 space echo into it and a bit of dry too) I just rewired the preamp on this one and added a negative feedback control
It's the exact same sized chassis and same power transformer as my current build

[Toxophilite]

Here's the still dusty top of the current build
i like the solid copper chassis, tried scratching it check.yup

[sluckey]

Is there a way I can test the power handling of an otherwise unknown output transformer?

Not really. Just assume it is a proper match for the tubes it's connected to.

[Toxophilite]

Thanks
I figured it would be adequate to the task
I was asking cause I know some amps, like the deluxe reverb are rated at 20 watts with 2 6V6, whilst others, like the vibrolux, are rated at around 12-14

Does the 433 volts at the rectifiers plates tell me anything usefull about the power transformer's capabilities

Hey AC427v, you replied earlier, you said you made an AB763, but instead of the tremelo circuit normally used (with the oscillator thingy) you used the bias vary tremelo
Am I understanding that right? That's something I'd like to try
 Is that an AB763 Princeton(there seems to be a Ab763 version of many of the fender amps..like deluxe, super etc etc) I think that one has a choke too...Out of curiosity why would I need a turret board for that?

[ac427v]

Mine started as a Vibrolux 5F11 build. Then became a Princeton AA964. Now it is a AB763 Deluxe Reverb without the reverb and with a bias vary tremelo instead of the opto system. I used a turret board because Doug Hoffman had laid it out on his "Boards pages" and that was way easier than me trying to figure out how to do it using tagstrips or making an eyelet board. If you are comfortable doing point to point wiring, it could be done that way.

I used the SLuckey AB763 Lite  as my starting point (attached). I added the bias vary tremelo from Hoffman's AB763OldOneChannel layout. It uses both halves of a 12AX7 instead of the Princeton version which uses only one half. I changed the 100 ohm feedback-to-ground resistor to 47 ohm to match what Leo did with the deluxe reverb. Also changed the dropping resistors in the power supply to get the correct plate voltages for the phase inverter and preamp stages. After that, there was tweaking fun to match my tastes. Addiction maybe???

[Toxophilite]

Thanks, more interesting information.Sadly I can't open the Slucky build PDF. My computer doesn't seem to like it.grr &^%&(*%^#*^&) ancient Mac

The other thing I'd need for this build(if I go a non vibrolux/semi deluxe route) would be a choke...I think I inadvertantly sold one a couple of weeks back but I have another on a Hammond L100 reverb/power amp chassis I have kicking around. It's sitting between two 50 uf filter caps... Would it be appropriate? and how could I tell without specialized gear? I do have a greenlee DM-210 multimeter..it measures capacitance too...but I don't think it does Henries...besides I've only heard of 8 Henries..Never heard of a Henry the 9th!

The tremelo you're describing sounds like the tremelux tremelo, is it?

[ac427v]

Too bad your mac can't take an Adobe Reader update. The sluckey schematic shows the wiring between the preamp and the phase inverter. You can figure it out by using the Hoffman layout and eliminating the circuitry for the reverb but sluckey makes it easy.

The Tremolo circuit looks like the 6G9 Tremolux or the 6G16 Vibroverb.

Your choke between two 50 uf filter caps sounds pretty hefty. I'd be tempted to try it. Others may have a more scientific method of determining the specs. Or you could use a 1K ohm 5 watt resistor instead of a choke.

[Toxophilite]

So I'm finally start digging in a little on this build

One thing I'd like to ask before I get going is regarding layout

If you've seen the inside of the chassis I'm working with

It has the Transformers at the bottom left
Above that are the power tubes and the rectifier
and above that on the left is the phase inverter/driver
With a 6AV6 to the right of the phase inverter/driver

The existing holes for the pots are across the top
Buuuut the 12AX7 with it's fancy hum control is at the bottom right corner
(originally I suspect for the sensitive phono stage)

My intial idea was to use the 6AV6 for a tremelo circuit
and the 12AX7 for the preamp (in, out to tone and volume, in again and then out to another volume control prior to the phase inverter)
But that would mean lot's of long lengths of Coax runing back and forth down the right side
I've always understood that longer lengths for audio signals aren't such a great thing
True??

I could try to move the whole 12AX7 setup to the top of the chassis

Or use it for a tremelo circuit and then for a preamp use the 6AV6 and the 7 pin socket next to it also with a 6AV6..mind you I don't have all the bits for a more complex tremelux style tremelo
but that can be remedied

I guess a more extreme option would be to place all the controls down the right hand side effectively changing the orientation

THis would shorten some lenghts of Coax and keep the whole power amp section on one side


What say those with real experience, of these options?...and is there another better one?
(other than by a proper fender style chassis)

[Toxophilite]

Oh and S.Luckey, I dragged your Ab763lite schematic over to my music computer and i could check it out.Nice! I like it! Can i use it? (for fun of course)
Also I was wondering as I have an extra gain stage, is it possible to add a vibrolux style tremelo to this lite setup?

[sluckey]

You can use anything I have posted on my website for any purpose you desire. My stuff is free, no strings. You may want to look around my website. There could be something else you want.

http://home.comcast.net/~seluckey/amps/index.htm

I highly recommend the Vibrolux 6G11 tremolo over the 5F11 tremolo especially since you are now considering an AB763 based amp. I would use this layout for that chassis.

[Platefire]

I saw your name from where you posted on my SF Pro project and decided I would check your project out. Nice conversion project. Looks like you got it going in the right direction. I've got help from these guys on the forum for years and have always done me good!  That layout sluckey proposed looks very good for what your trying to build. I'll be watching your progress 
Platefire

[Toxophilite]

THanks Platefire
I've always wanted a fixer upper fender amp for cheap myself
Nice to see someone else finding one

I was wondering, on my build, if it matters whether my OT is under the chassis, obviously Electrohome didn't think so. Any ideas?

[Toxophilite]

Thanks S.Lucky for the layout picture.That's pretty clea
I guess a little widening of existing holes and moving of sockets is in order!

In that even should I use the hum adjustment separate filment on the preamp?

Maybe just run those heater wires longer to the new preamp location?

[sluckey]

I was wondering, on my build, if it matters whether my OT is under the chassis, obviously Electrohome didn't think so. Any ideas?

let it be

I guess a little widening of existing holes and moving of sockets is in order!

No moving. Just ream and replace the 2 sockets I suggested.

In that even should I use the hum adjustment separate filment on the preamp?

Maybe just run those heater wires longer to the new preamp location?

Read the suggestion I made on the layout pic.

My suggestions are just that. There are many ways to lay out an amp, especially when you are doing true point to point. My suggestions are logical and should give you a fairly trouble free amp. I have a little bit of experience in amp conversions. The suggestions I made are exactly what I'd do if I was gonna use that chassis.

[Toxophilite]

Thanks for taking the time to do that!
I like the suggestions and will likely implement them all

I was initially was viewing the 'layout' picture in the thread and didn't notice the writing on the bottom
my apologies

And thanks again

[Toxophilite]

Hmm
in stalled one 12AX7 socket(from a baldwin organ)
I sure like those electrohome bakelite/fiber tube sockets..or whatever that brown stuff is
Though they're a little rinky-dink they have the lugs in a circle outside of the tube pins with a wider spacing. Nice cause there's more room and when the tube is wiggled it doesn't move the lugs around.
The ones I was going to install are more skookum looking black pastic ones with an aluminum setup for a tube cover but the lugs are the pins extended so they're really close to each other and inclined to wiggle.

Might just have to move that 12AX7 socket after all or scavange some off an organ chassis I have and add the tube covers on top

Time to work on the power supply as it's too late to drill!

[Toxophilite]

If I don't use the extra filiment supply, should I just put marrets over the ends, tape them up and forget them?

[Toxophilite]

And a dumb B+ question if I may

With only a rectifier in and no filter caps attached I measure 365 volts on the B+ supply
If I touch it to the electrolytic it was originally hooked up to (40 uf)
It jumps to 459 volts.
I'm quite curious, why is that?

I thought the filtercaps helped to smooth out the B+ current and keep it steady

[John]

On the tube socket: you can carefully bend those pins out a little to give you more room for soldering.

Extra filament supply: yes, just cap them off, coil neatly and stow them out of the way. Make sure they're not close to signal wires or the speaker jack.

[sluckey]

With only a rectifier in and no filter caps attached I measure 365 volts on the B+ supply
If I touch it to the electrolytic it was originally hooked up to (40 uf)
It jumps to 459 volts.
I'm quite curious, why is that?

I thought the filtercaps helped to smooth out the B+ current and keep it steady

That's quite normal. Without the filter caps, your B+ out of the rectifier tube is really just positive half sinewave pulses. In your case the peak amplitude of those pulses is 459V. But, your meter expects to see smooth dc. The meter is averaging the amplitude of those pulses and coming up with a smaller number. In a way your meter is lying to you.

When you connect a filter cap, it will charge up to the peak value of those positive pulses and hold that charge. Now you have a smooth/steady DC voltage rather than the pulses and your meter will correctly measure 459V.

[Toxophilite]

Cool
I understand sine waves to some degree, having done my fair share of editing
That makes a lot of sense, given some of the reading I've done lately
One more piece to the puzzle Thanks!

I 'll splay those %$#$% socket legs out!!!  That'll show them


Hey. The AB763 has a pair of 16 uf electrolytcs in paralell right after the rectifier
I've mostly found 22 ufs where I go..and I have 10 kicking around (all 450vdc)
I can just use them together can't I and get the same result 22+10 = 32
Would using just a 47 be overkill?? is there a special reason they have 2 other than to make up that value?

[John]

Using them in parallel eases the in-rush current from the rect. tube, which is easier on the tube. Using your 22 and 10 in parallel is fine, or even a pair of 22's in parallel. If you want, and have the room you can put a small ohm, higher watt (maybe 5W) between the 2 caps. Or, just hook 'em in parallel, that's what I've done with good results (nothing blew up  )
 That link below is an excellent article by Merlin Blencowe. I highly recommend his books, as well.


http://www.valvewizard.co.uk/Grounding.pdf

[sluckey]

Just use two 22µF in parallel, or use a single 33µF, or 40µF, or 47µF. But... You have already measured 459V out of your rectifier. I'd increase the voltage rating for the caps up to 475V or 500V.

[Toxophilite]

Hi Slucki
I've installed my tube sockets and cleanec out the chassis more
I have some lug strip from an organ (9 on each strip with two being attachments to chassis) that I'm going to pair up opposite each other so I can lay some things out ala your layout

i was looking at the grounds
On your Layout you have ground 1 and 2 coming off the board and then ground 3 which looks like it's either a rail or the chassis

Are all the grounds going straight to chassis, or is there a rail, or is it star grounded?

Thanks

[Toxophilite]

Okay
I've perused your site and figured out some stuff for ground ideal

Hey all
THough I don;t have a board i have some 9 pin lug strips that I can use to mount the filter caps all nice and neat in a row
Would I be okay/better off mounting these on the outside of the chassis?

[sluckey]

Referring to the guts pic... You have plenty of room (you did remove those old cap cans and tube socket, right?) to neatly install the filter caps to the right of the PT. Putting the filter caps on the outside of the chassis exposes dangerous high voltages unless you put a cover over them. See pic...



Referring to my note about connecting the hum balance pot to the green filament string... Don't do that. Just totally remove the hum balance pot. Put heat shrink tubing over the ends of the black filament leads removed from the hum pot and tuck leads out of the way. You don't need them. I just now noticed that the green filament string has a green/yellow center tap wire that is connected to chassis. That does the same as the hum balance pot.

Referring to the grounds on my AB763 Lite... The gold colored bar at the top of the page is actually a piece of #14 solid house wire. It floats above the pots and jacks and serves as a convenient buss bar to connect the grounds for the pots/jacks. Gnd 1 and Gnd 3 both connect to chassis near the input jack. Gnd 2 connects to chassis at the same point as the node A and Node B filter caps and pin 8 of the power tubes connect. Here's a pic of a floating buss bar...

[Toxophilite]

Wow
Thanks yet again
Yes I have cleared that area out, though I hadn't removed the old can caps yet, but I moved the tube socket and the rest and I'll save that trim pot
I just wondered if it would help with hum, There certainly is plenty of room either way. Inside or out.
I have some aluminum sheet from an old organ that I could've made a 'cap barn' out of
but if it won't make a big difference then I can also use it to put a piece over all the holes there'll be left in the chassis.
I happily have some ground buss bar from also from an organ (I should make up a modern acronym thingy 'FAO'= From An Organ)
The chassis is pretty well cleaned out, The only thing left is removing the power tube bias pot arrangement.
I've done the heater wiring for the new sockets and installed a couple of terminal strips, next some hole drilling for pots, then wiring in of new bits.
Onward

[Toxophilite]

Here's my heater setup
Is this good enough ?
I was also wondering if I at sometime decide to add another channel and use the one remaining 7 pin socket for a 6AV6, can I just run the same heater wires from the 12AX7
The original setup had the 12AT7 using the wires from one 6V6 and the rest of the 7 pins were running from the other
That's my ignorant heater question of the day
Still have to yank the can caps and bias setup on the 6V6s

[Toxophilite]

Here's a couple pictures of my mostly finished build
I still might be adding a 6G11 tremelo as suggested
It's point to point but I was using terminal strips so that I can use the fender layout for some things(The preamp, PI, Power supply) to make it simpler (which is why I imagine Fender used it, for mass production, makes sense)

As it's point to point it's bound to look messier than a classic fender board build.

It sounds good though I have a little distortion. It happens on the tail end of what I play
Has that real crapping out sound blat blat but it's comes a hint after.
It's not a lotm, just enough to be noticeable and thus annoying
I have to scoot around and check everything yet again
I wonder if it could be:
-My power and output transformer not being up to the more skookum blackface deluxe circuit
(They were originally a 5Y3 based hifi
- Maybe I did roast my output tranny a little??
- something partially shorting?
-or ??
You'll see my DIY plug in SS rectifier on top. THis gave me about 10 more volts B+
Good for the power and but I'll need to increase the resister prior to the preamp power supply. I've already increased to it 25k by adding a 15K resistor. Maybe try a 56K as I have some big ones

[Toxophilite]

I hope you folks don't mind that I moved back to this thread
I was feeling that I'd got off the specific subject of the other one
So, in trying to track down the slight distortion at clean volume in my amp,
I went over the circuit, literally with a fine tooth comb, cleaning things up and checking for bad solder joints or any connections inadvertantly touching

I now have 412 volts on the screen grids of the power tubes and around 405-406 on the plates
I think that's as close as I'm going to get it
There's -35.5 volts bias on the control grids
I've been tweaking the screening/voltage drop resitors going to the various sections
I have 15 K in the 1st position (12AT7 PI)giving me 177 and 174..in the ballpark of the required 180 and 170 though strangely opposite, the higher voltage is on the 82k resistor side.
Which makes sense to me but isn't how the fender schematic reads
THen I have 28k (2 56k in paralell, what I had.) prior to the preamp B+ which gives me pretty well spot on 180 volts on the preamp 12AX7 plates.
I was just testing it with my geetar at lower volumes and it doesn't seem to have any distortion now and sounds nice.
THough I have yet to test it at higher volumes, and will do so tomorrow

I found it interesting to see how, as you changed the two resistors , the voltages around them adjusted up and down accordingly. There's a sense of establishing a balance between the sections..Quite Interesting!

Also I was really happy to learn the simple task of making a solid state diode. They make sense to me for my style of playing and I have another amp I converted that I'm going to rewire a bit. It uses a GZ34 too.

[Toxophilite]

My amp is working quite nicely thanks
I can turn it up to about 7 before it starts to distort
I haven't tried turning it all the way up yet because I have neighbours and I don't want to pop the hifi JBL D130 I'm was testing it with

[HotBluePlates]

... I don't want to pop the hifi JBL D130 I'm was testing it with

It won't pop with a pair of 6V6's unless it's already damaged.

[Toxophilite]

yeah it should be able to handle 50 watts
but I'm just a little paranoid about it
It's a non doped surround and smaller voice coil gap version, so more potentially fragile
And I haven't ever really got it checked out
Might still get the surround doped by the local speaker wizards and they will check it for free
Still my neighbours might not like me testing it's volume potential
I'll wait and drag it down to the rehearsal space

[Toxophilite]

So thanks to all the helpfull folks here I've got the basic amp on my AB763 lite build working well.
 After fiddling around with transformers I'm moving it back to this thread as I have general build questions...should this be all one thread?? Am I hogging?
Anyway
I want to add the tremelo circuit.
It was suggested I use the 6G11 circuit as I like the 5F11 tremelo, it sounds cool.
So
I need 365 vdc to the tremelo circuit
On the 6G11 schematic it comes from A the same source as the B+ for the 6V6s
However on my build that's 407-412!
I do have 363 ish at the Phase inverter section
Would it be okay to take it from there??

Also , considering the original deluxe reverb tremelo circuit I guess I would be buying an optocoupler roach thingy
I hear this circuit is easier on output tubes

Any opinions/ideas

[ac427v]

Congratulations on your new amp. You must be working night and day to get it done!
I have used the nearly identical bias-vary tremelo from Hoffman's AB763old layout. Voltage comes from the screen node of the power supply. That was 420 volts on my vibrolux clone and 380 volts on my deluxe clone. Both worked great. I have had no signs that it wears or damages my output tubes. But then I bias this circuit on the cool side to get that nice fender clean sound. Maybe people who bias hotter have had different results?

http://www.el34world.com/Hoffman/images/AB763OldOneChannel.gif

It sounds like you may have solved your distortion problem with different dropping resistors. I found that I got more aware (sensitive) of this as I got to know my amp better. Eventually I changed the cathode caps on the first preamp tube. Others recommended 10 uf for the first stage and 4.7 uf for the second stage. Those values worked great for me too.

[HotBluePlates]

... I need 365 vdc to the tremelo circuit
...
I do have 363 ish at the Phase inverter section
Would it be okay to take it from there??

Yes, that's fine.

I want to add the tremelo circuit.
It was suggested I use the 6G11 circuit as I like the 5F11 tremelo, it sounds cool.
...
Also , considering the original deluxe reverb tremelo circuit I guess I would be buying an optocoupler roach thingy

You won't buy an optoisolator if you're copying the 6G11 trem, as it didn't use one.

The oscillators are substantially the same for both versions of a trem circuit, but the application of the oscillator output to the guitar signal is very different. The presence/not of the roach and the Intensity pot value and circuit position are very different in each.

So pick which one you want to do up front. It will save you money if nothing else.

Also , considering the original deluxe reverb tremelo circuit ...
I hear this circuit is easier on output tubes

IMO, the AB763 trem is no easier/harder on the tubes than the bias-vary trem of the 6G11 (and blackface Princeton, and other earlier Fenders). In fact, half the time it's turning the tube off (when the volume drops), which reduces tube plate current. If anything, I might argue it causes the tubes to run cooler by increasing the percentage of time the tubes are running at reduced plate current.

[Toxophilite]

Cool I will go ahead as planned

But then I bias this circuit on the cool side to get that nice fender clean sound. Maybe people who bias hotter have had different results?

Here's my new dim question..what exactly does it mean when it's said to bias hot and or cool, to me this would relate to the amount of bias voltage sent to the grids would , I'd have to go experiment but is it more negative voltage = less voltage at the plates or the other way around?
I really should install a bias pot!! then I could determine this myself

And what does changing the cathode caps on the preamp section do? reduces gain? less bottom?

[ac427v]

Smaller cathode bypass caps reduce the bass that the stage can produce. My ears hear less bass distortion but the same level of bass when changing a 22u cap to a 10u. When I change to a 4.7u cap there is even less bass distortion but I think I lose a little of the bass fullness that I like. So it is a balancing act to get enough bass (I like a lot) without the farty distortion. I just got some 6.8u caps that I will try tomorrow to see if that is the magic answer.

The AB763 Deluxe that I am building now has 400 volts on the plates because that is all the scavenged power transformer will make. It sounds good set at -34 volts of bias. It seems that you were using -35 volts with 410 volt plates which would suit my er taste just fine. Was that just luck? or the result of a lot of resistor swapping?

[Toxophilite]

HI
410 at the plates is about what I had after the choke
And I was using the bias steal from the princeton which gave me -35.5 volts
(I don't have a bias tap)
Just the way it fell out

[Toxophilite]

I got my tremelo circuit done, sounds good, I'll have to install a switch with a 1 meg or 1.2 meg resitor as I only have 2.25 meg pot (came from the orginal chassis) for speed control so I can get it really slow if I want.
Otherwise nice!

Hey ac227v. At what number on your volume control (approx.) do you start getting the 'farty' distortion?

[Toxophilite]

By the way I was consulting the Hammond L-100 schematic (which I should've done originally) and I was happy to discover the choke I scavenged from it is 4 Henrys which I believe is what the fender ones are.