Amp Tech Thread / Ask a tech Q

[The Riffer]

I think those have an A1M pot for gain. Since the area you are concerned with is the beginning of the taper, the A should have the slowest action at the beginning of the travel..So not sure that the pot change would affect this as you wish to. Maybe changing (increase value) the cathode resistors in v1a and  v1b to lower gain might get what you need. Typically dudes change (lower value) to get MORE gain but seems it would also work to lower gain.?.

Foxen?

[showdown]

Hey Riffer,
My Pharaoh has lost its smoothness! It's sounding gritty and sputtering, even with low gain settings. Doesn't matter where the diode switch is set either. Could it be an input transistor? Or do you have any tips what to check?

[RAGER]

Did you rule out the power supply and patch cables by swapping them out with known good ones?

[showdown]

Yup, power and patch cables are tested good, also tested a couple of other fuzz pedals in the same place on the pedalboard and they sound smooth and creamy.

There's plenty of output from the Pharaoh, it's just the distortion itself that's grainy/gritty, for lack of a better word. Sounds like non-musical, odd order distortion in a sense.

[RAGER]

Dang that sucks.  Mine is still sounding brutal.  Good luck.  Did you crack it open to see if it's anything obvious like a solder joint?  Maybe run a signal through it and poke around inside lightly.

[showdown]

Yeah, I better take a look inside. I really want to get it going before we start recording next month.

[jibberish]

heh. howabout shipping it to mark to fix and bless properly?   or has this one changed hands and not his responsibility anymore?

there's just something wrong with this picture where you guys are planning an exploratory to try and figure it out, when the person who makes them is here.


I would consult with mark before I did anything. email/bmail him.
if an op amp failed, what exactly are you going to do anyway? how would you even know how to test for a bad op amp? talk to mark is how.

[RAGER]

Nothing wrong with opening it and taking a look. If it were mine and all it was was a solder joint, I'd feel kinda silly for shipping it out for something simple.

[VOLVO)))]

What RAGER said.

Four screws is all you need to remove to check and jiggle shit. Riffsir likes DIY types. He'd probably trouble shoot over the phone with you.

[The Riffer]

Hey Riffer,
My Pharaoh has lost its smoothness! It's sounding gritty and sputtering, even with low gain settings. Doesn't matter where the diode switch is set either. Could it be an input transistor? Or do you have any tips what to check?

My initial guess is a bad solder joint on one of the associated components to the first two transistors. Taking the transistor out of bias.

heh. howabout shipping it to mark to fix and bless properly?   or has this one changed hands and not his responsibility anymore?

there's just something wrong with this picture where you guys are planning an exploratory to try and figure it out, when the person who makes them is here.


I would consult with mark before I did anything. email/bmail him.
if an op amp failed, what exactly are you going to do anyway? how would you even know how to test for a bad op amp? talk to mark is how.

I will fix any of my pedals for anyone for as long as Im mentally and physically capable. Cant say how long that will be. Exclusions are blood/piss/vomit/shitting on the thing. Hank 3's LSTR went through a basement flood, was submerged for days. He dried it out,  and it fired right back up. I woulda covered that if it didnt work..I won't cover user mods or improper power supplies..and shitting on it.
I am happy to fix and ship it back, or am happy to help troubleshoot. As jib says tho, If you dont know ask.

Nothing wrong with opening it and taking a look. If it were mine and all it was was a solder joint, I'd feel kinda silly for shipping it out for something simple.

Agreed, and it is indeed encouraged. Can be a very simple fix, worth a try.

What RAGER said.

Four screws is all you need to remove to check and jiggle shit. Riffsir likes DIY types. He'd probably trouble shoot over the phone with you.

Exactly. As Rager says, run a signal through it, and poke around EVERY component and wire solder joint with a pencil. Any bad solder joint would likely show itself this way. If no luck, I will fix it with a new pcb.

[VOLVO)))]

I still wanna build one of these for myself... Just for funsies.

Even though my Pharaoh is the best Pharaoh.

[The Riffer]

Can certainly be done. I heard someone is selling DIY Pharaoh pcbs. Pretty cool.

[VOLVO)))]

Sell me the parts.

[RAGER]

Sell him the pcb.  Make his source his own damn prats.  Project!

[VOLVO)))]

So.. Lazy...

[Danny G]

Just had a build idea/thought/theory:

I've been using a second TU-2 in my guitar chain as a poor man's channel switcher.

I don't need an ABY box per se, I just need to have a split signal with a kill switch on one.

Could I just make a box with two output jacks, one straight thru from the input  and the other wired to the switch (with an led wired in to let me know its on)?

Or due to buffering concerns or some other something-or-other do I need to build/buy a proper ABY?

[RAGER]

Unless you already have a work station set up and those type of parts on hand and are building shit regularly, I would just buy one cuz they cheap nowadays.

[Danny G]

I have probably everything I would need to build the simple splitter/kill switch

[jibberish]

Just had a build idea/thought/theory:

I've been using a second TU-2 in my guitar chain as a poor man's channel switcher.

I don't need an ABY box per se, I just need to have a split signal with a kill switch on one.

Could I just make a box with two output jacks, one straight thru from the input  and the other wired to the switch (with an led wired in to let me know its on)?

Or due to buffering concerns or some other something-or-other do I need to build/buy a proper ABY?

I think a simple test would be to just hard-wire a splitter and see how that sounds with the 2 amp chains. I would guess that once the weak hi-impedance guitar signal goes through any pedal, it has now been buffered/boosted and probably would work. splitting the guitar output would maybe change the tone since it is looking into half the impedance as before, but maybe it doesn't matter either, especially if those signals are going through pedals anyway.

the pain in the ass would be installing and powering an LED heh.  otherwise a stompbox switch just single pole would work for the kill. double pole would be cleaner, kill the ground too. I would probably do that, like a true bypass switch would work.

[Danny G]

Here's what the signal chain would look like:

Wah--TU-2--Blues Driver--Phase 90--Tremelo--Splitter

Signal 1: amp 1
Signal 2: Loop Station--amp 2

The secondary TU-2 has been functioning as the splitter.

Hence having a dedicated switcher as I'm just tired of pulling it from my bass pedalboard haha

I've been using the signal split to have the loop station go into its own amp. Or when LS is not in use the second amp can act as a boost channel.

[jibberish]

yeah, you are all active buffered. just do it. it will work.

listen for drops or changes in the amp that is always on when you kick the second one in and out. that's the only thing I could think of to watch for. 

I wonder if a dead stompbox would work as the kill switch. full true bypass then full kill into the guts. then just add that after one of the splits on a stock hardwired a/b splitter

I wonder if a good stompbox, just not powered would also work

"laziness is the true mother of invention"  you can quote me if you like. heh

maybe there is a way to do this without lifting a soldering iron or a screwdriver.

[Danny G]

"laziness is the true mother of invention"  you can quote me if you like. heh

Just did \m/,

[RAGER]

Well in that case I've got a couple noise generators around (pedals with bad components). I'll just run them through my beatstep and a Sherman filter bank for light weight live rig.

[Danny G]

maybe there is a way to do this without lifting a soldering iron or a screwdriver.

I could just find a used TU-2 on the cheap, heh

Am thinking of running this part if the chain on a separate board, I only need the loop station for OoS.

Plus I added one of my lady's Boss foot switches to the Loop Station to better control it. So that's three extra pedals right there.

Looking forward to remedying this situation

#gear #fun #imissbuildingshit

[jibberish]

a video is worth 1k words

introducing the $200 killswitch