Spencerleehorton
Well-known member
Yeah I have a 250R 1w pot so I will try this and see if it improves a little
Jose Plexi mods
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Spencerleehorton
Well-known member
I thought i had a 250 ohm 1 w pot but it was a 100R wirewound, ive added 47R to each leg and it does reduce hum a fair bit, only thing is its all over one side?
would i need to make the resistor bigger? 75 ohm on each side? or is it ok to have it turned all one way?
would i need to make the resistor bigger? 75 ohm on each side? or is it ok to have it turned all one way?
Last edited:
Spencerleehorton
Well-known member
I might remove the two 47R resistors and see if it improves
Spencerleehorton
Well-known member
the Humdinger doesnt really seem to do much with 100R pot, i'll wait for the 250R to arrive then try again.
Also looking at the OD channel to make it less lower mid heavy, ive installed the depth control now and this gives great control over the bass but the mids need a bit more help getting through so thats my next step.
going to look at byassing the2.2nf cap and listen to what influence it has, also the 1nf cap on the OD gain at switching this in and out at the moment does seem to do anything, so probably a mistake in wiring again.
Also going to look at cathode resistors and bypass caps.
Also looking at the OD channel to make it less lower mid heavy, ive installed the depth control now and this gives great control over the bass but the mids need a bit more help getting through so thats my next step.
going to look at byassing the2.2nf cap and listen to what influence it has, also the 1nf cap on the OD gain at switching this in and out at the moment does seem to do anything, so probably a mistake in wiring again.
Also going to look at cathode resistors and bypass caps.
Spencerleehorton
Well-known member
This next SLO-50 build will hopefully be much more accurate to the original.
Alva Goldbook
Well-known member
You should build a Fender Champ or 5e3 instead. The most common mistake made by new builders is building level 10 difficulty amps before they’ve mastered their skills well enough to execute it.
Spencerleehorton
Well-known member
Already built one Alva, sorry not everyone’s as good as you bud!! Merry Xmas, will get there one day!!
Alva Goldbook
Well-known member
You should build to match your skill level. Starting out I built perhaps 6-8 small single ended amps. I did this to improve my building skills and to test various circuit ideas like a different tone stack. I tried various construction styles to become a more well rounded builder. I build an amp in a hammond stomp box chassis to teach myself how to work in a limited space.
Simple circuits like these are great training exercises because any issues can only be a limited number of things. Correcting mistake means not adding a mistake on top of another one. One of the key skills you must master is how to solder and soldering neatly. Learning proper lead dress. Learning how to desolder something. Wires emit magnetic fields. This isn’t just about making things look pretty. It’s about making them function correctly.
All wires should be as short as possible.
No wire should touch each other.
A high current wire should be particularly isolated from a small signal, i.e. heaters and grid wires.
Alternating current wires should be neatly twisted.
If two wires must cross over each other, they should make a neat “+” shape to limit their interaction with one another.
Don’t rush your builds. Take your time. Savior the experience. It’s not good enough if it’s half right. The hardest thing to learn is to not rush. If it takes you an hour to solder a single resistor precisely right, then take an hour to do it.
Simple circuits like these are great training exercises because any issues can only be a limited number of things. Correcting mistake means not adding a mistake on top of another one. One of the key skills you must master is how to solder and soldering neatly. Learning proper lead dress. Learning how to desolder something. Wires emit magnetic fields. This isn’t just about making things look pretty. It’s about making them function correctly.
All wires should be as short as possible.
No wire should touch each other.
A high current wire should be particularly isolated from a small signal, i.e. heaters and grid wires.
Alternating current wires should be neatly twisted.
If two wires must cross over each other, they should make a neat “+” shape to limit their interaction with one another.
Don’t rush your builds. Take your time. Savior the experience. It’s not good enough if it’s half right. The hardest thing to learn is to not rush. If it takes you an hour to solder a single resistor precisely right, then take an hour to do it.
john12ax7
Well-known member
Chassis looks nice, did you make it?
Spencerleehorton
Well-known member
No I bought the chassis
john12ax7
Well-known member
Where from? Never seen a raw slo chassis before, they always seem to be painted
Spencerleehorton
Well-known member
View attachment IMG_0636.jpeg
Here is the very nearly finished SLO-50.
Gotta a couple of tidy ups still to do.
1R resistors have been shortened and are more out of the way.
Speaker gnd not connected on this photo.
VR5 I’ve taken out and just jumpered that switch.
Fx loop gnd was put in but not on this photo.
Bias pot needs to be changed.
Footswitch needs finishing.
Sounds really good in comparison to my first build, this will defo be my main amp now for live and studio for most things.
Ended up using KT77 tubes.
Just need to build a head enclosure for it.
Here is the very nearly finished SLO-50.
Gotta a couple of tidy ups still to do.
1R resistors have been shortened and are more out of the way.
Speaker gnd not connected on this photo.
VR5 I’ve taken out and just jumpered that switch.
Fx loop gnd was put in but not on this photo.
Bias pot needs to be changed.
Footswitch needs finishing.
Sounds really good in comparison to my first build, this will defo be my main amp now for live and studio for most things.
Ended up using KT77 tubes.
Just need to build a head enclosure for it.
Spencerleehorton
Well-known member
I bought the chassis from tube town, along with the mains txf and choke.
All the preamp tube sockets I had to redrill along with the output and txf.
Should have done the output tube sockets as well but they ended up being ok I thought with what I’ve done.
Gonna buy a half sheet of 18mm ply and cut out the box for it.
Notch the edges and glue then cover in tolex, I’ve found some nice lattice chrome metal grill which I’ll use then I should be done.
