"Build Your Own DS-1 Distortion" doc: Updated with new mod and sound clips

[5thumbs]

Wow a most thorough PDF !!!
It must have taken an insane amount of time to put together,KUDOS for the result and for the sharing.

It's a work-in-progress that started in Jan 2008, so a lot of the work on it has been done over time since then.  I have no idea how many hours I've spent on it (let's just call it "a bunch"), but I'm glad to keep adding to the doc as long as I can think of useful ideas for mods for the DS-1.  I'm glad you found it useful.

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FYI, I've updated the doc again.  I learned some info about the 1S2473 diodes used in D4/D5 in the MIJ DS-1 that made me combine the previous MIJ Mod and MIJ-Plus Mod into one updated MIJ Mod.  The MIJ Mod now takes the new information about 1S2473 diodes into consideration and applies it to the mod to get a very close approximation of a MIJ DS-1 with a MIT, post-1994 DS-1.

For all the details, you can download the updated doc from the link in my sig.  For those of you too lazy to do that, here's the scoop: 1S2473 diodes clip between 0.92V and 1V.  This is much higher than the 1N914/1N4148-type diodes (0.65V typical) used in the post-1994 DS-1 pedals.  This partly explains why the MIJ DS-1 sounds better than the MIT, post-1994 DS-1.  It also means that, if you have your clipping diodes clipping around 0.9V-1.0V, you'll be approximating the proximity-to-clip of the MIJ DS-1.  The now-retired MIJ-Plus Mod tweaked the D4/D5 diodes to raise their proximity-to-clip to around the correct forward voltage, so it is no longer necessary, now that the MIJ Mod has raised its proximity-to-clip in the D4/D5 diodes.

Thanks!

[zombiwoof]

FYI, I've updated the doc again.  I learned some info about the 1S2473 diodes used in D4/D5 in the MIJ DS-1 that made me combine the previous MIJ Mod and MIJ-Plus Mod into one updated MIJ Mod.  The MIJ Mod now takes the new information about 1S2473 diodes into consideration and applies it to the mod to get a very close approximation of a MIJ DS-1 with a MIT, post-1994 DS-1.

For all the details, you can download the updated doc from the link in my sig.  For those of you too lazy to do that, here's the scoop: 1S2473 diodes clip between 0.92V and 1V.  This is much higher than the 1N914/1N4148-type diodes (0.65V typical) used in the post-1994 DS-1 pedals.  This partly explains why the MIJ DS-1 sounds better than the MIT, post-1994 DS-1.  It also means that, if you have your clipping diodes clipping around 0.9V-1.0V, you'll be approximating the proximity-to-clip of the MIJ DS-1.  The now-retired MIJ-Plus Mod tweaked the D4/D5 diodes to raise their proximity-to-clip to around the correct forward voltage, so it is no longer necessary, now that the MIJ Mod has raised its proximity-to-clip in the D4/D5 diodes.

Thanks!

Are those 1S2473 diodes impossible to find?  Can you just sub those diodes, instead of adding the other diodes that your MIJ mod suggests (if they can be found)?.

Al

[5thumbs]

Are those 1S2473 diodes impossible to find?  Can you just sub those diodes, instead of adding the other diodes that your MIJ mod suggests (if they can be found)?.

Neither Mouser, Digi-Key, nor Small Bear have 1S2473 diodes.  Same for eBay...nada.  Google Shopping...bubkis.  So upon completion of initial scan, I'd say they're pretty much impossible to find.

Three 1N34As or 1N4148+1N34A are much easier to find and should do well.  Mind you, the bridge rectifier clipping arrangement used in the Huevos Grandes mod (in the doc) will give you the equivalent of 3x1N34A diodes in each direction, but only uses 5 diodes.  That arrangement will save you a 1N34A diode to tuck away and use another day.

[5thumbs]

There are other single-diode options that will clip around 1.0V.  The 1N4245 is one (1.2V), 1SR139 is another (1.1V) and let's not forget the good ol' red LED (often 1.0-1.2V).  I'm not sure that the 1S2473 is magic as much as having the proximity-to-clip around 1.0V.  Using other diodes with this Vf should give a similar result as the apparently defunct 1S2473.

[Ry]

Cool info!  I was about to undo a mod that I didn't like.  I'll try replacing these diodes with red LEDs while I'm at it.

Thanks!

[5thumbs]

Cool info!  I was about to undo a mod that I didn't like.  I'll try replacing these diodes with red LEDs while I'm at it.

Thanks!

Just remember that the "clipping shoulder" contour of the red LED will be different from that of the silicon 1S2473.  (Germanium diodes would be different from Si and LED as well.)  That doesn't mean one is empirically better than the other, it just means that you'll have to listen to them and pick the winner to your ears.  Aside from that, stay somewhere near 1.0V proximity-to-clip and you're probably close enough for most folks' criteria.

Good luck!

[axelrod]

Excellent doc . Very useful . Many Thanks .

[WGTP]

Yes, cool doc.  You can also add a resistance between the diodes and Vf and adjust to desired clipping level.  Try a 5k trim pot.  Most LED's I have measured come in at 1.7V.  I like 2 SI/1 SI 1 GE.