JHS Pedals' Overdrive Preamp Gives You Two Versions of the Very Original V1 Big Box DOD250

I’ve been known to be quite partial to the DOD250 circuit - per the below visual. Where I’ve mostly been interested in the more extended-range compact variants of that great sounding Overdrive Preamp. The original big box Gray Box version first came out in the early 70’s - around 1974 I believe coinciding with a number of other hard-clipping OpAmp drives - including MXR’s very similar Distortion+. In fact, as Josh alludes, the very original big-box 250’s (650 / V1) were part-for-part replicas of the MXR Distortion+. In 1978 DOD shrunk their 250 down to the compact Gray Box design (V2) we’re so familiar with  - and switched from Distortion+ 1N270 Germanium Diodes to Silicon 1N4148 Diodes.

The original edition had some rare NOS Mojo parts, and included some special version of LM741 that Josh Scott says isn’t actually critical to the sound - but where the Diodes and Capacitors are the key elements - and in particular the input capacitor value. It seems every single one of those early 250’s was made with slightly different parts and values and they can vary enormously. Whatever the Mojo parts are that Josh needs - he was able to source those out of disused radio equipment from 1972. Interestingly there are two versions at launch - a pretty exactly JHS ’Throwback’ replica of the big box 250 - enclosure and all - based on the #75 of that original run. Which to my mind is a touch clunky - only 250 of those limited editions were made (immediately sold out!), and they had a suitably lofty price tag. While Josh also launched a standard / regular pat of the range BB-size Overdrive Preamp which is more readily available, and more affordable - per the main visual above.

You have just the same 2 authentic Level and Gain knobs - actually in reverse order to the compacts. The special sauce here is that the one enclosure accommodates two of Josh’s favourite versions of the big box V1 250 - where the Up voicing is Clearer, Brighter, Louder and with more Headroom / Less Clipping, while the Down voicing is Grittier, more Harmonic and Textured, and with More Clipping. I think I will probably gravitate towards the more textured Down / Grittier voicing. Note also that the Gain control sort of acts as a kind of pseudo presence control simultaneously as the profile of the output gets progressively brighter as you dial up the gain.

Part of me would have liked to have seen some sort of separate / additional EQ control here too for more granular control / refinement - but I can sort of understand the need to be ’authentic’ - also we have a relatively large enclosure with side-mounted jacks. Where most of my favourites are compacts with top-mounted jacks! :