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Re: SLO-100 Clone - To PCB or not...

9/15/2000 3:10 AM
Re: SLO-100 Clone - To PCB or not...
You might want to consider doing the tone stack like the yamaha Soldano clone instead of the layout you currently use. I had some hum in mine till I took out the Soldano LDR power supply and built the LDR power supply just like the yamaha SLO amp. After that I had no more hum. I just wonder that I had the 6vac string for the old LDR supply tapped into the middle between the power tubes and the preamp tubes and that might have caused my hum in the first place. I talked to Joe just a while back and he urged me to go back into my SLO cuase I was losing volume. so I went back in and removed the mods on the fx loop and a preamp out I had connected right before the PI. I think that sucked some of my tone and volume out a bit. After removing all that the amp just screams now. I cant believe how good it sounds now, The sustain is great and when I back off my guitar volume I get this smooth light gain distortion that sounds just unbelievable. If I were you I wouldnt tear it all down again I would change the board layout and try an aproach to the two tone stacks like the Yamaha SLO. Good luck.  
9/15/2000 3:21 PM
Dave Paetow

Hi guys,  
I took some pix of my Soldano SLO-100 for Jeff, and I also posted them at this address:
9/16/2000 6:22 PM
Joe L

Schematic correction alert! Dave, there is a section that is covered by wires on the circuit board right below the 1000uF capacitor. From looking closely at your pictures that almost show it clearly and others that I have, the wiring on the schematic is wrong for the switching network. A clear picture under those wires and of the resistors that connect to all those traces in the middle of the board would really help confirm my suspicians.  
..Joe L
9/16/2000 6:44 PM

Joe, After seeing this error on the amp does it mean that the schem that Steve A has needs corrected again? If you revise the schem please send me a copy as Im possibly going to do a SLO clone for a friend after he heard mine the other day. By the way, Im glad you talked me into going back into my SLO again. After the recent changes this amp really screams now. I just connected it to my new fender 2x12 cab clone I built with the t75 watt celestions and I just got thru playing an hour and a half straight non stop. This thing is inspiring now.  
9/16/2000 7:33 PM
Joe L

So far it looks like the 61.9 ohm resistor connects before the 33 ohm resistor instead of after it. The problem is that when I work it up in Electronics Workbench, I have to change the resistor values to make it work. When I look closely at my pictures, I can only confirm the values of the 47ohm and 61.9 ohm resistors, all the others are too blurry and don't appear to match the schematic. Stand by until I confirm some resistor values, these may just be a later version than the schematic we have.  
..Joe L
9/15/2000 4:07 PM
Jeff Stapleton

I have been of the opinion for some time that the second tone stack is adversely affecting tone. I am really tempted to redo it according to the original SLO design, with schematic errors corrected of course.  
Thanks to the pics that Dave provided, along with those on Joe's site, we can now really get a good idea how they lay things out in there.  
Still considering...
9/17/2000 10:02 AM
Craig D
Re: Schematic corrections
Joe, Mitch, Jeff (and anyone else who knows :))  
I am curious about the correction that puts the output of the 3rd stage before the parallel 2.2M/120pF resistor/cap pair instead of after it as per the schem. From the excelent pics posted it looks to me that the schem is correct.  
Am I going blind?  
Thanks all  
Craig D

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