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I’m looking to add a global tightness control circuit to my amp. My initial idea was a 3 way tightness switch to change the coupling cap value after the first gain stage and instead I was thinking of implementing a low cut pot after the first stage coupling cap. I figure a .047 for the coupling...

Currently still tweaking my Jet City 50H with custom preamp voicing mods. Started as an SLO spec mod and have tweaked values to be more modern, easier to play, and tighter. The stock screen filtering is 50uF and the PI filtering is at 68uF. I’m wondering if lowering or raising the values might...

I have a mod to move the SLO/Jet City effects loop after the tone stack. In this mod V4 and the Tone stack take the place of V3 making the first half of V4 the 4th gain stage. Since the 1st half V3 was a 1.8K cathode with a 1uF bypass cap & V4 has 2.2k cathode without a bypass cap should I...

I recently powered up and did preliminary checks on my Jet City 50 which is modded to SLO spec. Everything is great except for some noise related to V2. While searching for the source of the buzz/hum, I noticed getting close to V2 made it louder. I swapped the tube out and it is 80% better but...

In this schematic, can someone elaborate on it further and help me understand how the thump and hair switches are affecting the negative feedback, Obviously the the 4.7nf on the pot is a resonance control, but how do the 39K and 47K resistors and 10pf caps affect things? I would like to try this...

I’m sure this is pretty common knowledge but based on the diagram, how would I wire the 60V winding to use for my bias supply? I have a bias circuit already on the board which used a 60V tap on the original PT so I’m not sure what to do with the common. I’m assuming it’s supposed to be attached...

Just wanted to get an idea what people shoot for as an initial B+ voltage post rectification. Or even what you prefer on the high voltage winding at the transformer. Specifically in a modern high gain application. Even a range would be informative. This can be a new amp build or for modding...

Just curious if anyone has ever used the 2nd (Crunch/Clean) half of V1 on an SLO circuit to do a 5 gain stage mod? Obviously would need to change Biasing and Filtering and so on for all the stages but I’m pretty determined to make this happen. I’m thinking of keeping the stock CF/Tone stack...

I have a Jet City 100HDM that uses an Optocoupler switching circuit to switch channels. The circuit is very similar to the SLO circuit which uses two optocouplers to switch the gain controls and two for the channel volumes. There was a known channel bleed issue which I obtained the parts and...

What are some of your favorite diodes and or tansistors and combinations for clipping circuits and why? How are you combining them and where in the amp circuit are you placing the clipper? Just trying to get a feel for the range of combinations everyone uses and the thought process behind it. I...

Hope I’m appropriately posting this question apologize if I’m out of place. I’m about two years into my journey of learning amp modding and my question is what would be the advantage if any of running two capacitors in parallel as opposed to one single capacitor in a circuit? Looking at some...