TH Black Eye (Soldano GTO) prototype build

[ICTRock]

He confirmed the following to me, THANKS Matt!
All of his parts were from Tayda except Tube Sockets & jj ECC83S Tubes.
He didn't confirm if he had a buffered pedal in front ?? :
Maybe splitting the wires into 2 pairs of 3 is an alternative????

View attachment 30658

finally a gut shot of one whining ... let me familiarize myself with the build docs and I'll give you some feedback from my amp building experiences

first bit of troubleshooting, remove V1 and report back whether you're still getting whining. this effectively halves troubleshooting for me.

 

[tcpoint]

I tried the 12 volt linear regulator. Just a hair bit better. I put a Mach 1 (lightspeed) with the gain down and the volume around unity and the whine went away. I'm going to wire directly from the input and output jacks to the stomp. If that doesn't solve it, I'm going to go to shielded cable. I'd like to skip the first step but I want to help solve it for everyone else. BTW, I want to play it today instead of work.

 

[music6000]

finally a gut shot of one whining ... let me familiarize myself with the build docs and I'll give you some feedback from my amp building experiences

This pedal actually works without an issue but the builder didn't confirm if he had a Buffer in front.
The other Builds here with issues still have an issue with a Buffer in front.

 

[tcpoint]

I was a little concerned with the input wiring next to the smps. Maybe some kind of resonant frequency gets created.

 

[music6000]

I tried the 12 volt linear regulator. Just a hair bit better. I put a Mach 1 (lightspeed) with the gain down and the volume around unity and the whine went away. I'm going to wire directly from the input and output jacks to the stomp. If that doesn't solve it, I'm going to go to shielded cable. I'd like to skip the first step but I want to help solve it for everyone else. BTW, I want to play it today instead of work.

Have you tried it with a Boss or Buffered pedal in front of it

 

[tcpoint]

I have couple buffers around here. I, also, have several Boss and Cornish clones around here. I want to make sure that there's no charge pump. I'll try that next.

 

[music6000]

Do you guys have any Ferrite or Ferrite Bead Axial Leaded like this
You could try on the power wire!
Spaceman Effects use them on there Builds:

 

[ICTRock]

second bit of troubleshooting, move that ribbon cable away from the output jack. the tube gets hot, but not melt plastic hot.

third bit, 100K is not enough grid leak resistor. change R21 to 1M

 

[tcpoint]

I have some Ferrite Beads, somewhere. I have both the axial and smd.

 

[music6000]

I have some Ferrite Beads, somewhere. I have both the axial and smd.

Spaceman Effects use them on the Power & Input pads!

 

[ICTRock]

a part of the problem here is that the input impedance of the pedal is under 100K

 

[music6000]

a part of the problem here is that the input impedance of the pedal is under 100K

That's why you should Polish it, I mean Buff it!

 

[ICTRock]

That's why you should Polish it, I mean Buff it!

or you replace the one resistor as indicated above ...

 

[music6000]

or you replace the one resistor as indicated above ...

Yes, it's Standard practice for 90% of the circuits to have 1M to Ground on the Input!!!
On the Output is a totally different Ball Game I've found!!!!

 

[ICTRock]

Yes, it's Standard practice for 90% of the circuits to have 1M to Ground on the Input!!!

again, this is coming from amp building and the purpose of that resistor in a tube triode stage ... you can't look at a valve project the same as a tube screamer or rat ... hence why you guys have problems you figure a buffer is the fix for.

 

[music6000]

again, this is coming from amp building and the purpose of that resistor in a tube triode stage ... you can't look at a valve project the same as a tube screamer or rat ... hence why you guys have problems you figure a buffer is the fix for.

Well, one way to find out is for the Builders here with an Issue to change it out & hopefully it is a success!
My PCB has just landed on the other side of Australia so another week before I get to build it!
Thanks for your Input.

Cheers music6000

 

[ICTRock]

Well, one way to find out is for the Builders here with an Issue to change it out & hopefully it is a success!
My PCB has just landed on the other side of Australia so another week before I get to build it!
Thanks for your Input.

Cheers music6000

pages 11 - 13 from the Bible ... http://www.valvewizard.co.uk/Common_Gain_Stage.pdf

 

[tcpoint]

I just looked at the schematics of the SLO-100 and it has a 1M resistor. The schematics from freestompboxes have a 100K resistor. Seems like a no-brainer to go with a 1M.

 

[ICTRock]

I'm not here to say that the schematic is necessarily incorrect to the pedal ... just that there was a single schematic from back in 2011 with no gut shots etc etc and traditional amp design disagrees with this particular part value

 

[music6000]

I just looked at the schematics of the SLO-100 and it has a 1M resistor. The schematics from freestompboxes have a 100K resistor. Seems like a no-brainer to go with a 1M.

Well, Get the soldering iron & 1M resistor & get it done, It's 12.48 am in Western Australia & I need some Shut Eye.
I'm making a cup of Tea & buy the time I drink it, I hope to read a Report!!!