Hi
I am about to build a Soldano SLO100 replica. I have everything, but the layout. My main issue is about the ground. This is a high gain dual channel amplifier, and if I start to mess around with the ground.
Usually, this is what I do
- Ground star 1: very close to the power plug to connect the ground cable
- Ground star 2: close to the input jack. From there I connect a bare cable that goes all the way on top of the POT. Every single ground from the preamp is connected there
- Ground star 3: close to the Power Supply. I put another bare cable that goes from the power supply to the power amp. Here I connect the power amp ground, Power Supply ground and center taps
- I also use blinded cables for the signals coming from the Input Jack and Master Volume.
So far, this works properly in every amp that I made (from 5W to 50W mostly with clean tone and some effects like Reverb and Tremolo). I got a super low hum, and everyone is happy with the tone.
The thing is that after reading the article that I attached about Grounding, I realized that I might introduced some ground loops in my circuit.
So I would like to know if anyone has some pictures from the layout of a real Soldano. I think this would be the best reference to take
Thank everyone
I am about to build a Soldano SLO100 replica. I have everything, but the layout. My main issue is about the ground. This is a high gain dual channel amplifier, and if I start to mess around with the ground.
Usually, this is what I do
- Ground star 1: very close to the power plug to connect the ground cable
- Ground star 2: close to the input jack. From there I connect a bare cable that goes all the way on top of the POT. Every single ground from the preamp is connected there
- Ground star 3: close to the Power Supply. I put another bare cable that goes from the power supply to the power amp. Here I connect the power amp ground, Power Supply ground and center taps
- I also use blinded cables for the signals coming from the Input Jack and Master Volume.
So far, this works properly in every amp that I made (from 5W to 50W mostly with clean tone and some effects like Reverb and Tremolo). I got a super low hum, and everyone is happy with the tone.
The thing is that after reading the article that I attached about Grounding, I realized that I might introduced some ground loops in my circuit.
So I would like to know if anyone has some pictures from the layout of a real Soldano. I think this would be the best reference to take
Thank everyone
Soldano SLO100 - Overdrive
Hi,
I built a Soldano SLO100 replica based on the circuit attached. I used a Tube Town PCB for the circuit.
I also followed some tips regarding grounding. There are two points attached to the chassis
1.- GND from power cord
2.- Circuit GND. This one is as closed as possible to the Input Jack. I used a bare cable to attach the different grounds from the circuit. I putted the Power Supply GND at the end of the bare cable, together with the Power Amp section
The amp works perfect, when I play NORMAL the sound is very clean and the hum is incredible low.
If I put the PRE-AMP OVERDRIVE Knob on maximum and I start to increase the MASTER OVERDRIVE, at some point there is a huge distortion noise coming from the amp. This is without the guitar connected.
When the guitar is connected, there is a feedback when I start to increase the MASTER OVERDRIVE.
I know this is a high gain amplifier, but I was not expecting all this noise coming from the amp.
There is anything that I'm missing from the built? Has anyone built a similar amplifier before?
Thank a lot, any help will be appreciated
Hi,
I built a Soldano SLO100 replica based on the circuit attached. I used a Tube Town PCB for the circuit.
I also followed some tips regarding grounding. There are two points attached to the chassis
1.- GND from power cord
2.- Circuit GND. This one is as closed as possible to the Input Jack. I used a bare cable to attach the different grounds from the circuit. I putted the Power Supply GND at the end of the bare cable, together with the Power Amp section
The amp works perfect, when I play NORMAL the sound is very clean and the hum is incredible low.
If I put the PRE-AMP OVERDRIVE Knob on maximum and I start to increase the MASTER OVERDRIVE, at some point there is a huge distortion noise coming from the amp. This is without the guitar connected.
When the guitar is connected, there is a feedback when I start to increase the MASTER OVERDRIVE.
I know this is a high gain amplifier, but I was not expecting all this noise coming from the amp.
There is anything that I'm missing from the built? Has anyone built a similar amplifier before?
Thank a lot, any help will be appreciated
Attachments
Just for testing purposes, pull v2 and see what happens. I'm guessing that is where the feedback is coming from given the symptom description. If you have any, try a few lower gain tubes (12au7, 12at7) in that socket. There are a whole lot of places for signals to weasel their ways back into that spot. Lead dress and layout are super susceptible also.
It gets better when I change the tubes. I think I will leave the 12AX7.
However, I ran into another issue. When I switch on the CRUNCH there is a weird noise coming, like a constant CRACK CRACK CRACK. I checked all the connections, and it seems to be properly connected. I recorded in the attached video. Not sure if the problem is clear enough.
Does anyone have experience fixing this kind of issues?
However, I ran into another issue. When I switch on the CRUNCH there is a weird noise coming, like a constant CRACK CRACK CRACK. I checked all the connections, and it seems to be properly connected. I recorded in the attached video. Not sure if the problem is clear enough.
Does anyone have experience fixing this kind of issues
?
Well, I didn't put it. But C9 affects the OD. I had the impression that could be the switch S4 that is defective or that there is a bad joint.But I am not sure it is the case
Well yes, but for small values the effect is above the freq range of your amp and prevents oscillation, and for larger values it removes OD fizz, and prevents oscillation...
And if you have oscillation..., and it is on the schematic...
(Sorry, I can't help with the cracking sound)
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@blackwhaleamp
This page has a nice analysis of the amp:
Soldano
This picture of a real SLO is from another thread on here, it is easy to see the star ground:
https://www.diyaudio.com/forums/att...-100-clone-screenshot-2019-12-08-15-08-55-jpg
I'd try to duplicate the grounding, shielding, and wire routing as much as possible.
This page has a nice analysis of the amp:
Soldano
This picture of a real SLO is from another thread on here, it is easy to see the star ground:
https://www.diyaudio.com/forums/att...-100-clone-screenshot-2019-12-08-15-08-55-jpg
I'd try to duplicate the grounding, shielding, and wire routing as much as possible.
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Here is the now discontinued PCB set from Tube Town, you can see right
through the PSU board in case anyone wants to duplicate it:
Tube-Town Store - Soldano SLO100 PCB Set - DISCONTINUED
through the PSU board in case anyone wants to duplicate it:
Tube-Town Store - Soldano SLO100 PCB Set - DISCONTINUED
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