someone upped this on "another" forum...worth a look!!!!!

[pinkjimiphoton]

Does the Bypass Balance pot set the volume of the buffered signal when the effect is bypassed, or am I reading the wiring diagram wrong? Also, is it worth building the stereo out since that's just buffered dry signal?

Here's what I'm thinking of doing:
-Replace Bypass Balance pot with a Master Volume pot
-Leave out stereo jack/switch
-Leave out Lo Z input
-True bypass

I wanted to run these ideas by you guys before making any changes to the design, since I'm the guinea pig and all. Jimi and Dino, do you think these changes will affect the character of the unit as you know it? Would you miss the stereo out or the Lo Z input if they were gone? Do you wish it had a master volume?

.
bypass balance is so you can adjust the dry output with the signal bypassed by the unit; the phase II seems to want to run a little below unity gain.
the stereo out is a nice feature, as you can drive two amps or mixer channels with it, and the effect is only in the main output. this can be handy, and makes it sound HUMONGOUS.
a master volume isn't gonna be useful unless it has some gain or at least make up gain, imo.
true bypass may be nice, but it may be a bit of a hassle...i don't know enough to speculate.

the lo z in is handy to have, as you can drive a stereo signal into the unit, and use the lo z balance knob to make sure both inputs are driving the unit equally.

that said, i think a higher impedance on the input would help quite a bit. i ran it last nite last in line after my usual pedalboard, and it was self-oscillating...didn't do that at home by itself, it was almost the classic fuzzface/crybaby kind of runaway.

the fuzz could be improved with an extra stage just for volume...when mine had broken, it had THE BEST FUZZ SOUND EVER....liquid and insane...as soon as i replaced the formant trimpot, the fuzz got weak again. it's almost like just below unity when engaged. i'm gonna play with it some and try to dial it in a little better.

onwards and upwards.

[pinkjimiphoton]

Jimi and Dino, have either of you measured the AC voltage off the transformer yet, or measured the DC voltage at console pad 17? I'm getting ready to order parts for this, and I'd like to know if your units are really running at the stated voltage before I order a power supply.

On the power supply, I've been thinking about that. For a clone, a DC-output wall plug would be a whole lot better. Not knowing how much current it eats until/unless it gets measured on a real or clone, it's hard to design a charge pump to work right. If the current's high, it may be hard to get a charge pump to get to 35V.

I like the idea of running it from a 24Vdc nominal output wall wart. These are cheap and easy to find, and usually have an output that is larger than the stated. I just bought a couple for another project. They put out 31.1V unloaded. The other option is to use a 15-18V AC output wall wart and use diodes and caps to double it to over 35V. Lots of options, not much real information. Mouser stocks 48Vdc output wall warts. That should be OK for the raw power. There's a regulator on the PCB anyway. Just have to make sure it doesn't burn out with 48Vdc in.

Given that the circuit is already laid out for AC power, could we just use a transformer like in the original units? Or would mounting that in the enclosure cause too much hum? Also, what AC voltage would rectify to +36v DC using the existing power scheme?

this thing REALLY needs better power supply filtering, it has quite a ripple to it. that's why i ran it last in line with my pedalboard, so the inherent hum wouldn't get too much amplification. it sounded absolutely sick with a fuzzface, boss super overdrive, superhardon clone and tc nova delay going into it...coolest sound ever. almost uncontrollable, but so psychedelic it could make one tumescent like audio viagra.

since my girl will be away for a few days, i'll try and get voltage readings etc off the fall board...i am paranoid about opening the top again and anything else breaking in the process. i may be a p**sy, sorry, but i wanna be careful...trying to keep it as stock as possible!!

but...that said...for the clones, i think 3pdt switches with led's for the fall board are a given. will just be so much easier.

[pinkjimiphoton]

I will measure the AC and DC voltages tonight. One thing that strikes me as peculiar is that one drawing says +36, and the other +35. But, then again, there are two "Lo Z" pads as well, so I'm assuming it's a typo.

Personally, I'm not quite sure what the Hi Z does yet, but I would retain it, just in case. I run my rig in stereo, so yes, I would keep the stereo. I often run two different signals left/right.

Master volume? DUDE... you're reading my mind. I was messing with it last night, and I was thinking how nice a master volume would be. But, I think that MV and TB would be best left as DIY mods that one could do themselves. There are not complex mods. We could just publish the procedure, and let them decide.

As for the TIP29, loks like a repair note to me.

seems there's a lot of typos on the schem as ya get inside it some. and i don't even know that much about this stuff!! some of the things in the unit aren't there, some of the things on the layout don't match the schem...

drummers. <shakes head> should stick to beating on stuff for a living, not designing electronics.

but ya know...in the long run...they got (for the time) a lot of it right!!

just curious, but why the hell does this thing HAVE to be run at 35 volts?
couldn't the same circuit be made to run off a regular wall wart?

could the transformer be replaced with a torroid?

is it worth replacing the main filter cap r.g. mentioned with a much larger cap to get less ripple?

these and other questions will be answered on the next installment of the "upped on another forum" thread...

[digi2t]

Hey Keppy,

Could you list all the points where you want me to take readings from? Then I could print it, and have it handy when I have at it. I know Jimi's a bit ansy about opening his top because his is in rough shape compared to mine, so I don't mind taking it on. Just make a list of points (resistance or voltage), and I'll fill in the blanks. Relax Jimi, I'll get this one bro.

As for the master volume, I use a clean stereo preamp in some loops to boost the signal on some of my effects to unity, since I have others that are louder. My GR50 synth is a good example. I need to boost it to compete with my GNX3, then I use it's volume to bring it down a touch to unity. The master volume would be useful for me, but maybe not for others. In any case, not really a blip on my radar, since I could mod it myself later. As R.G. implied, we need to validate this sucker before we even start thinking about the esoteric stuff.

the fuzz could be improved with an extra stage just for volume...when mine had broken, it had THE BEST FUZZ SOUND EVER....liquid and insane...as soon as i replaced the formant trimpot, the fuzz got weak again. it's almost like just below unity when engaged. i'm gonna play with it some and try to dial it in a little better.

I find the fuzz weak when the formant is engaged as well, but it depends when you set the treadle. Somewhere in the middle of my pedal range, it sounds really good. Toe down, really thin, heel down, dark and buzzy. Then again, I'm still trying to understand why the Fuzz Mix slider reacts so differently when in Fuzz, or Fuzz Voice.
Maybe just a trimpot to adjust the bias of the fuzz circuit, but I'm not gifted enough to understand how the fuzz circuit really works, or if a trimpot will actual help (or do) anything here. Give to Caesar what rightfully belongs to Caesar... your call R.G.  Again, this could be a post build mod.

The Hi-Z and Lo-Z inputs are just that - separate amplifiers with different input impedances. They're all mixed right into the same signal path again after the input amplifiers. I haven't messed with how much gain, speed, response, etc. yet. With the advantage of that half-century I was talking about, the input amplifiers become fairly quaint, as well. The Hi-Z isn't that high, but it's where you'd put a guitar to avoid treble loss. Lo-Z was probably meant for putting a microphone into this, although I can't imagine wanting to do that musically.

I kind of had a handle on the principles of Hi/Lo Z, it's just that with my present setup, I wasn't getting any appreciative difference insofar as the sound of my unit was concerned. BUT.... a microphone into this thing? Hmmm, sounds just like the kind of demented, twisted, bizarre thing that I would try. Leave the Z inputs as is Kep  Mmmmmmmuuuuuaaaaaaahhhhhhhhhaaaaahhhhhhaaaaaaahhhhhhhaaaaaa!

[pinkjimiphoton]

heh heh...how else ya gonna put DRUMS thru it?? lol!!!

[digi2t]

heh heh...how else ya gonna put DRUMS thru it?? lol!!!

HEY.... take a mic off the bass drum, and run it in, at the same time as the guitar! Then run the PII into a stereo delay.


KEPPY.... KEEP THE Z INPUTS!!!!!!!!!!

[pinkjimiphoton]

heh heh...how else ya gonna put DRUMS thru it?? lol!!!

HEY.... take a mic off the bass drum, and run it in, at the same time as the guitar! Then run the PII into a stereo delay.


KEPPY.... KEEP THE Z INPUTS!!!!!!!!!!

indeed!!! feed the stereo output into the other input....heh heh...

[Keppy]

I hear you guys! I'll keep it as is. Sounds like the things I thought of leaving out would be missed, and a passive master volume wouldn't do much good if it's already below unity gain.

I'll just have to mod it AFTER I build it! 

[pinkjimiphoton]

yah, well maybe WE can get it RIGHT....LOL!!!

[Keppy]

It has to rectify to more than 36V. The 36V is the zener voltage for the regulator. To be an effective regulator, the raw DC power has to be from a few to several volts higher than that; moreover, the raw DC when it sags down on ripple in the incoming filter has to never get below maybe 38-40V. I can't figure out enough from the circuit to peg the voltage exactly, but I suspect that the peak DC voltage after the rectifiers is in the range of 42-50V. Knowing the transformer volts would clean up a lot of this.

Hmmm...I have an unregulated 15v supply that puts out 21-22v. Doubling that might be JUST high enough to drive the Zener without burning anything out. Maybe I'll try that first.

Just looking at the power supplies you show and the circuits, you're going a lot of overkill on power supply current with either one of those. This thing doesn't use much current. Once I know the transformer output voltages, I can do a better job of suggesting a power supply.

I know. Those are just the only 36v DC supplies I could find.

Could you list all the points where you want me to take readings from?

Console board pads 2 & 3 for the AC input, pad 17 for DC output from the regulator. While you're at it, it might be worthwhile to take readings at all the test points noted on the layout. I say MIGHT because I haven't looked thoroughly enough to know if those points are carrying any DC bias or would have any bearing on the settings of the trimpots. Probably just reading the power supply is fine for now. Of course, if I have to debug much I might be pestering you for all the transistor voltages later 

Thanks for the help guys!

[digi2t]

Of course, if I have to debug much I might be pestering you for all the transistor voltages later 

Don't worry Kep, whatever you need man. If tranny voltages is what it takes, just say the word. Nobody ever gained anything without a little sacrifice. When we all embarked on this mission, it wasn't to go half way.

Like Jimi said, it will live again. I'll post your requested readings later tonight.

Cheers!

[digi2t]

heh heh...how else ya gonna put DRUMS thru it?? lol!!!

HEY.... take a mic off the bass drum, and run it in, at the same time as the guitar! Then run the PII into a stereo delay.


KEPPY.... KEEP THE Z INPUTS!!!!!!!!!!

indeed!!! feed the stereo output into the other input....heh heh...

OMG.... I could feed it into my Stereo Panneur! YIKES!!!! So many possibilities, so little time!

[pinkjimiphoton]

heh heh...how else ya gonna put DRUMS thru it?? lol!!!

HEY.... take a mic off the bass drum, and run it in, at the same time as the guitar! Then run the PII into a stereo delay.


KEPPY.... KEEP THE Z INPUTS!!!!!!!!!!

breathe, dino...breathe~! 
indeed!!! feed the stereo output into the other input....heh heh...

OMG.... I could feed it into my Stereo Panneur! YIKES!!!! So many possibilities, so little time!

[R.G.]

Some of the meat of the discussion gets lost 21 pages deep.
I posted a couple of things here: http://www.diystompboxes.com/smfforum/index.php?topic=92125.0 under "   Ludwig Phase II Clone Tech Notes"

I noted a couple of wall adapters from Mouser that work for a power supply in a doubler arrangement.

Also, can you measure the actual operating voltage on C11?

[Keppy]

Dino, it looks like we also need values for the Bypass Balance and Lo Z Balance pots.

[pinkjimiphoton]

sorry, lost my mind there for a few...
i'm getting ready to crack it open tonite to play with the trimmers, it's set just a wee bit too hot right now and i wanna dial in the yoyoyoy thing a little better...

i'll try and get voltage readings etc while i'm in there and post 'em, and will see about getting the values of the pots...but i think dino already posted that in here a couple pages back.

[Keppy]

R.G., got a link to the Fuzz switch candidate you found?

[digi2t]

Hi Kep,

OK, first off the pots. Bypass balance is a 10K, and the Z pot is 5K.

For the voltages, the unit settings were as follows;
Footswitches;
BYPASS OFF (meaning effect on)
All other switches OFF

Treadle-Toe down

Console;
All sliders set to 0 (minimum)
FUZZ switch-FUZZ/VOICE
SELECT switch-BOTH
SLOW START
All Formant switches - OFF

Voltages;
Console pad 2 to GND = 37.0 vac
Console pad 3 to GND = 37.0 vac
Console pad 2 to 3 = 74.3 vac
Console pad 17 to GND = 33.45 vdc (took about 1 minute to stabilize)
Console capacitor C11 to GND = 46.0 vdc
Motherboard pad 5 to GND = 33.45 vdc (took about 1 minute to stabilize)

Motherboard Test Points (all to GND pad 14);
TP1 - 0.624 vdc
TP2 - Toe down = 1.01 vdc  Heel down = 13.85 vdc
TP3 - 3.807 vdc
TP4 - 2.292 vdc
TP5 - 3.74 vdc
TP6 - 3.81 vdc
TP7 - 3.80 vdc
TP8 - 9.26 vdc
TP9 - 18.54 vdc

Anything else you need?

[pinkjimiphoton]

fall board voltages, all dc...black probe to ground, effect not bypassed, but stereo, fuzz, and animation footswitches off

q1
e 0
b .63
c 2.99

q2
e 3.65
b 4.18
c 10.25

q3
e 0
b .60
c 7.69

q4
e 2.77
b 3.07
c 10.26

q5
e 3.31
b 2.63
c .20

q6
e 0
b .60
c .20

q7
e 3.57
b 4.23
c 8.77

q8
e 3.56
b 4.21
c 11.21

q9
e 19.77
b 19.12
c 11.21

q10
e 10.58
b 11.21
c 18.70

q11
e 19.35
b 18.70
c 15.80

q12
e 3.58
b 4.21
c 15.80

q13
e 3.58
b 4.22
c 14.88

q14
e 3.55
b 4.15
c 17.35

q15
e 3.55
b 4.21
c 11.40

q16
e 19.62
b 18.96
c 11.40

q17
e 10.77
b 11.41
c 18.88

q18
e 19.53
b 18.88
c 15.62

q19
e 3.59
b 4.21
c 15.62

q20
e 3.59
b 4.18
c 17.60

q21
e 3.31
b 3.83
c 10.26

dino...thanks for doing the top board bro...i know i'm lame, but as really noided about busting something, and lost my notebook with all the wiring and crap i did...

hope this helps some...do i need to read both sides of the electrolytics etc too?

say the word,,,

peace!!!

[Keppy]

Thanks for the info guys!