[HELP] Boss DS-1 Distortion above 12 O'Clock position fails

[tonyjross]

G'day all,

My Boss DS-1 has stopped working when the distortion control is positioned further than the 12 O'Clock position. Beyond 12 it is like the pedal is losing power and the volume drops right off.

I'm assuming a component has pooped itself but I'm not sure what to replace first ?

Nothing looks out of the ordinary on the board, as far as smoke pouring out of it or random fires etc.

Anything that could be suggested for a fix would earn you a warmth in my heart (Priceless really)

Cheers.

Tony

[thermionix]

I would suspect the pot first.  Measure before ordering a replacement.  If you do replace, I'd recommend reverse audio (anti-log) taper instead of the original linear.

And welcome, and g'day too.

[tonyjross]

Thanks for the welcome

Pot, ah, see, I knew I came to the right place !

I wouldn't have thought about that until I'd replaced all the other components.

I'll see if a quick swap of the Pot fixes things and report back. (If I can find one in my not at all carefully organised "Draw of stuff") - With an additional test too before swapping happens.

I should have mentioned its the ET-28F Board too, that might be useful for someone, somewhere.

Tony

[tonyjross]

FIXED !!!

The pot itself on the DIST control had twisted inside the case shorting one of the lugs.

The knob was pretty tight so it must have been dropped at some stage, poor little thing.

Nut tightened and now working as normal.

Thanks again !

Tony

[thermionix]

Awesome.  I came back to add "try contact cleaner before replacing" but seems it was even simpler than that.

[tonyjross]

Ah, Pedal has gone back to doing what it was doing before.

If I turn past the 12 O'Clock position the LED drops in brightness and the volume drops and there is popping and other dying component sounds (Sounds like a burp/fart).

I left it on 100% for 20 minutes and everything was fine after I shifted the POT and it randomly did the above for a split second then came back later on today.

Something isn't letting the signal through I suppose. Would it be a tranny perhaps ?

Tony

[PRR]

> it randomly did the above for a split second then came back

That's a simple bad contact. Wire, pot-wiper, ANY connection.

Simple in concept. Often devilishly hard to find.

[thermionix]

LED brightness drop coinciding with volume drop suggests a power issue.  Either it's getting grounded or shorted to something, or the feed of the power is intermittant.  Are you using a battery or external power?  If you use a battery, and almost always a battery, there could be some oxidization on the contacts of the internal switch of the DC jack.  If you use external power, check for cracked solder joints on the board/DC jack.  MANY other possibilities though.

[tonyjross]

Thanks for the replies !

I'm running off a power supply which is happily running other pedals with a daisy chain connector. I've tried the power supply with the troublesome DS1 by itself and I still have the same issue.

Tomorrow I'll pull the POT and see if things change, but when I remove the D5 diode the DIST POT works up to the 3 O'Clock position. So I'm suspecting component elsewhere is angry with me.

This pedal was either modded by me several years ago or someone else modded it and I tweaked it.

I'll try a battery too as a "Just in case" scenario.

Cheers !

Tony

LED brightness drop coinciding with volume drop suggests a power issue.  Either it's getting grounded or shorted to something, or the feed of the power is intermittant.  Are you using a battery or external power?  If you use a battery, and almost always a battery, there could be some oxidization on the contacts of the internal switch of the DC jack.  If you use external power, check for cracked solder joints on the board/DC jack.  MANY other possibilities though.

[thermionix]

modded

Ohhh, all bets are off then.

[tonyjross]

It's weird the pedal works beyond the 12 O'Clock position, but after about 30 minutes it stops working beyond that point. (No controls are altered in this time frame)

Is that a capacitor or transistor overloading ? I've re-soldered the whole board and tried a replacement of two of the bigger Caps (Power section) but with no success.

I'm flying a bit blind here and Google is letting me down.

Forgive my persistence, I don't want to shelve this pedal!

(I ran a Sine wave through all my pedals and this one has a really nice curve - closer to my Boss OD2 Turbo OverDrive than it is to my MIJ DS1)



Tony