Update: Kits now available in the shop here. Update: Carsten posted a YouTube video here. Carsten Møller of Møller Mod in Denmark got in touch to enquire about modifying the Stompville True Bypass Relay project to make an A-B switcher. After a few emails and some discussion, we agreed on a specification and we present… Read More »
Updated – see below for information on improving the design to lower the output impedance. We have had enquiries about adding volume and tone controls to the Unbalanced Piezo Preamp (available in the shop here). The PCB was not designed for the addition of these controls, so this article represents something of a hack. Here’s… Read More »
Following on from our articles on the Unbalanced piezo preamp and Guitar leads, buffers and true bypass we present a project to build your own JFET buffer pedal. The circuit is essentially the same as in the unbalanced piezo preamp with a few tweaks and may be built into a Hammond 1590B or similar stomp-box… Read More »
Update: Modules are available in the shop here now. I finally decided to retire the Altoids Piezo Preamp Kit and Altoids Piezo DI kit projects from the shop; I received good feedback from customers – but not enough people bought them. Fully built and tested Altoids Piezo Preamps are available from the shop here. The… Read More »
Phantom Piezo Preamp Modules are available from the shop here. Sometimes, back-of-the-envelope calculations do not tell the whole story (and neither do simulations). This article is a follow-up to the original article Phantom Piezo Preamp and addresses some errors and misconceptions that have arisen. The Phantom piezo preamp module (available in the shop here) has… Read More »
Update: reStomp re-ampers available for sale in the shop. Back in 2012, I wrote about re-amping and offered a design for a transformer-coupled interface between balanced-line output from a professional recording device and the unbalanced and lower-voltage input to a guitar amplifier. If you’re not familiar with re-amping, the idea is that you record (say)… Read More »
Following on from my previous blogs about Connecting Loudspeakers to Amplifiers and Passive Dummy Loads for Amplifiers here is a project for a modest passive dummy load with a twist – I have included a differential ‘scope probe to facilitate monitoring of the signal on an oscilloscope. I managed to score a new-old-stock Grayhill switch… Read More »
We don’t do much SMD (surface mounted) work here at Stompville. When it comes to the True Bypass Relay however, smaller may just be better, so we designed and built a surface-mount version to see how small we can realistically make it – and the answer is about 30% smaller. That is 30% smaller on… Read More »
Update: Please see also Phantom Piezo Preamp revisited Update: Phantom Piezo Preamp modules are available for purchase in the shop here. A few years ago, Alex Rice put a design up on the internet for a phantom-powered JFET piezo preamp. Here’s the schematic of the original design as reported by Zach Poff: So far so… Read More »
Update: Kits available in the shop here. I finally got round to revisiting the manual JFET matcher project. Please take a look at the earlier article and refresh yourself on the details of the three tests we can perform to help match JFETs: Vgs(off) – which we approach with a gate-source resistance of 10M Ohms… Read More »