183 Bass pot ineffective in Rock mode

[evirob]

As the title says, the bass pot on my 183 build doesn't do anything in Rock mode. No change at all, no matter where you set it. I can't understand it as it works fine in Jazz mode. I've been over and over and can't see any discrepancies vs the layout. Anyone have any ideas? I'm tearing out what little hair I've got left!

[mhartman]

Post a pic. It should be something simple

[evirob]

Thanks, I'll see if I can get a decent pic tonight.

[evirob]

Ok, so I was taking some pics of my switch/pot wiring, and I was reluctant to post them because if I'm honest my wiring is not the neatest, and I wasn't sure they'd be much good to anyone willing to help me debug it.

So I had one last look at the schematic, and for some reason I decided to draw my own layout for the Jazz/Rock switch (having mostly built my amp from the layout). So I notice, by my reckoning, the jumper should go between the bottom 2 lugs, not between the pole and the lug. And I remember someone else mentioned this in the sticky thread regarding the 183, and I now remember I ignored this at the time because Jelle said the layout was correct.

Now I'm aware of Jelle's work, he obviously knows a thing or two about these amps, so I assume even now there is something I'm misunderstanding, but in any case I re-wired that jumper and blow me if it didn't fix the problem.

So I'm just following up here in case anyone else encounters the same thing. And for that matter, if anyone could explain to me how both the layout and schematic could be correct (especially when it only works one way for me) I'd be most grateful. I hate not understanding things.

[ToneMerc]

Ok, so I was taking some pics of my switch/pot wiring, and I was reluctant to post them because if I'm honest my wiring is not the neatest, and I wasn't sure they'd be much good to anyone willing to help me debug it.

So I had one last look at the schematic, and for some reason I decided to draw my own layout for the Jazz/Rock switch (having mostly built my amp from the layout). So I notice, by my reckoning, the jumper should go between the bottom 2 lugs, not between the pole and the lug. And I remember someone else mentioned this in the sticky thread regarding the 183, and I now remember I ignored this at the time because Jelle said the layout was correct.

Now I'm aware of Jelle's work, he obviously knows a thing or two about these amps, so I assume even now there is something I'm misunderstanding, but in any case I re-wired that jumper and blow me if it didn't fix the problem.

So I'm just following up here in case anyone else encounters the same thing. And for that matter, if anyone could explain to me how both the layout and schematic could be correct (especially when it only works one way for me) I'd be most grateful. I hate not understanding things.

Did you use an on/on switch? Some of the other layouts are wired using a on-off-on which serves as a front panel PAB switch verses rear and the jumper is orientated differently than 183.

TM

[evirob]

Ah, yes. I used on/on. Same thing caught me out on the bright switch, now you mention it. I didn't initially realise it was supposed to be on/off/on til I looked more closely at the schematic.

[mhartman]

Great! Sounds like you now have the answer. Despite many initial problems after builds, I've never run into a problem that a bit of patience and perseverance didn't solve. Nice work!

[evirob]

Agreed. Now I can't wait to crank it, but it's late and I'd wake up the whole street

[ToneMerc]

Agreed. Now I can't wait to crank it, but it's late and I'd wake up the whole street

The pride felt from one's accomplishment is priceless, crank it and enjoy!

TM

[jelle]

Glad you figured it out!