Kingslayer question

[ChRa]

Hello, I built the Kingslayer--had some trouble fitting it in the 1590B because my 1uF pot is tall, but eventually worked out the bugs.

I've built a couple of GuitarPCB klones, and this sounds very different. On the GPCB pedals, the gain  (I mean amplification, not clipping...I know the Klon isn't a distortion machine) is so ferocious that I can get a big boost with volume at 40%. With this one I get unity volume at about 60%. Also, the clipping switch doesn't seem to have much effect (not necessarily surprising from what I've heard). It still sounds great, but I wanted to make sure that something isn't going wrong. As I said, that 1590B is packed and it's certainly possible that something could be shorting b/w the pots or under the dual gang pot.

Please let me know what you think, thanks!

[madbean]

The difference in boost settings is probably due to the taper. The Kingslayer uses an audio taper 10k volume pot whereas the Klon(e) uses a linear taper. The still have about equal amounts of total boost, but the positions on the control are in different places.

For the diodes, you are not going to hear much difference until the gain is at least half-way up. Maybe even 2/3rd. Also, it will depend some on diode choice. For example, if you use 2 different sets of germaniums you might hear very little difference (or any). Diodes where there is a larger gap between forward voltage drop will be most noticeable.

[ChRa]

Thanks Brian! It looks like the GPCB uses a 50k log for volume, so that may be the difference (?). I think they might've also substituted some components to get more gain.

Does it sound like the pedal is performing like you'd expect-- in terms of unity gain at 60-70% and not much clipping until gain= ~75%?

I have to say I like the tone a lot more than the GPCB version. Great work!

One request in the future for boards with diode switches--it'd be great to have a diode lift option when using on-off-on switches. I love using the Rat as an overdrive with the diodes bypassed.

[Ralfg]

With the Kingslayer you could do a diode lift just by using an on-off-on switch, but without the clipping diodes I would assume you would get no distortion because I don't think the op amp would clip on its own, if it does it would be very minor and you would just probably be boosting volume.  You could increase gain by making R10 larger and making R8 smaller.  But, I think it would also lose some thickness in the tone, so you would have to mod other parts to compensate, probably increasing C7, maybe C6 to let more bass through. 

[controlFreak]

I'm working on trouble shooting my build but after reading this perhaps there's nothing wrong with it. All the knobs work and do what they are intended to, just sounds really dark and not very loud. There is some boost available but not what I would expect from what is hailed as a great booster. Maybe that's just how this thing is supposed to sound? I'm playing through a clean solid state amp so maybe that's my problem. I also subbed 2k resistors for the 1.5k spec for R5 and R13, about to swap those to see if it changes anything.

[madbean]

It should not be dark and it should have plenty of boost. You need to post some more info to help diagnose your issue. This includes voltages and a pic of the build.

[controlFreak]

ahhh, I found my problem... 82nF at C14 instead of 820pf. A bit murky