# Lazy J … what is this switch?



## bluehugh2 (Mar 10, 2006)

Got a Lazy J J20 tweed… it’s been modded… any idea what this switch may do? Thanks! Hugh


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## Mark Brown (Jan 4, 2022)

cuts out the negative feedback?

my phone might not be the best vantage point lol


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## bluehugh2 (Mar 10, 2006)

That's what I guessed... but I really don't know!


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## greco (Jul 15, 2007)

I can only see one wire and a cap attached to it. Maybe I'm wrong!

Is the "open" style Switchcraft jack part of any circuit?

I hope some amp techs, builders, etc see this.

@Paul Running 

@Alan Small 

@nonreverb , 

@Latole

@WCGill


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## loudtubeamps (Feb 2, 2012)

I've seen same amps online with switch...pretty sure it's a factory install.
A better pic of the switch terminals and wire path would answer your question.
Is there an owner's manual available online?
My guess with what I can see is a low value cap on what may be the footswitch jack.


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## loudtubeamps (Feb 2, 2012)

Lazy J J20


There are Tweeds and then there are TWEEDS and the Lazy J lineup without a doubt, represents simply the most incredible take on a vintage tweed ever produced. The tones, from the most pristine cleans through to the most harmonically beautiful and complex overdrive will take your breath away and...




destroyallguitars.com


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## Ronniedblues (Jan 29, 2021)

I once had a switch like that in same location darned if I can remember what it did


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## Latole (Aug 11, 2020)

Just one wire from this switch ? 
What's on other side of the switch ? Both sides of capacitor ?


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## mturk (Nov 27, 2013)

Bright cap switch if that’s an input jack

never mind I see it’s an output jack


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## Alan Small (Dec 30, 2019)

From the hot lead of a speaker out jack it may be part of feedback loop that appears to be incompletely wired up....the small cap across the two terminals of a spst would not be serving any purpose without a destination point(it would bypass the cap when switched when a circuit is completed)

More poking about and pics will supply the answer.

I read that these are wonderful sounding amps.


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## Adcandour (Apr 21, 2013)

Honestly, I would just reach out to Jesse ([email protected]). I thought I messaged him a while back. This is what he sent that mighthelp.:


Hi Chuck,
I hope all is well!

I don't have a manual specific to the J10 yet...something I will need to get around to before too long.

So, Let me answer your questions one by one.
Okay, you've got the Volume and the Tone. Both of them are push/pulls. The Tone push/pull acts as a mid boost (like on the J20) and the Vol push/pull is a Bright Switch.
So it makes the sound more sparkly when it's pulled up.

The knob over on its own, next to the ON/OFF switch, is your attenuator. Just like the J20.
When it's all the way up, past the click, it's off. That means the amp is on full power then.
Turning it anti clockwise past the click will engage the attenuator.
Turning it down further will reduce the output of the amp.
That allows you to keep the Volume control turned up so you get the natural turned up drive...and without getting too loud by reducing the output with the attenuator.

It does this by reducing the operating voltages inside the amp. But the tremolo has to keep running at the full voltage...otherwise it would stop.
So as a result the tremolo becomes more and more intense as you turn the attenuator down.
That is normal. The fix for that is to simply turn down the INT knob on the tremolo module.

If you have any questions, just give me a shout.
All the best,
Jesse


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## bluehugh2 (Mar 10, 2006)

Thanks! I just emailed Jesse… stay tuned!


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## loudtubeamps (Feb 2, 2012)

looks like its on the footswich jack....will be interested in it's function.


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## Adcandour (Apr 21, 2013)

I vaguely remember having to turn something on within the J20, but don't remember exactly what for - possibly the reverb or the tremolo options. But I can't rememebr if it was the J10 or the J20 that had the tremolo


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## WCGill (Mar 27, 2009)

Seems to me if you have the amp, flip the switch and don't know what it does, then it does nothing.


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## Latole (Aug 11, 2020)

loudtubeamps said:


> looks like its on the footswich jack....will be interested in it's function.
> 
> View attachment 459975



Look the 2 wires, it is the speaker jack output


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## mhammer (Nov 30, 2007)

The switch appears to be a SPST type. If there is a cap wired to it, and it is somehow wired up to the output, then it is quite possible it alters the negative feedback. I don't know if there is a Presence control of any sort inside the amp, but controlling the negative feedback is the central function of a Presence control. Since it normally reduces the harmonic content introduced at the output stage, when the output transformer is pushed, if I'm right the switch may not have any discernible effect unless one turns up reasonably high, so as to generate the harmonic content that gets turned into negative feedback.

But, I could be wrong.


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## greco (Jul 15, 2007)

Just curious...and interested.


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## bluehugh2 (Mar 10, 2006)

Ok … so the proof is in the pudding… push the switch towards the front of the amp and the pudding gets, … thicker, richer… towards the back of the amp … thinner, brighter… a little less volume or fatness.


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## RBlakeney (Mar 12, 2017)

bluehugh2 said:


> Ok … so the proof is in the pudding… push the switch towards the front of the amp and the pudding gets, … thicker, richer… towards the back of the amp … thinner, brighter… a little less volume or fatness.


ahh the ol pudding switch


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## Mark Brown (Jan 4, 2022)

So cathode bypass. Alan had it.

Damn him for not teaching me more


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## Budda (May 29, 2007)

Judging by that description I’d wager negative feedback value would be accurate.

then I read MB’s reply.


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## greco (Jul 15, 2007)

bluehugh2 said:


> Ok … so the proof is in the pudding… push the switch towards the front of the amp and the pudding gets, … thicker, richer… towards the back of the amp … thinner, brighter… a little less volume or fatness.


So is it basically a one fixed cap tone changing switch? (with pudding...of course!)


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## Mark Brown (Jan 4, 2022)

Budda said:


> Judging by that description I’d wager negative feedback value would be accurate.
> 
> then I read MB’s reply.


I'm probably just wrong lol

To be fair, it could almost be either given the description, I can't quite see it. I'm not that smart yet but I will give myself credit for knowing what those two things actually are


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## bluehugh2 (Mar 10, 2006)

Still waiting on J’s answer… but he appears to be lazy…


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## Mark Brown (Jan 4, 2022)

Is the amp basically a 5E3 Mr. @bluehugh2 ?


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## bluehugh2 (Mar 10, 2006)

Yup


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## mhammer (Nov 30, 2007)

bluehugh2 said:


> Ok … so the proof is in the pudding… push the switch towards the front of the amp and the pudding gets, … thicker, richer… towards the back of the amp … thinner, brighter… a little less volume or fatness.


Is that true at all volume settings, or just some?


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## bluehugh2 (Mar 10, 2006)

all settings


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## Latole (Aug 11, 2020)

IMO the switch is not working, one wire is missing.


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## Paul Running (Apr 12, 2020)

The importance of schematic diagrams: a proper schematic reveals all with no guessing required.


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## Paul Running (Apr 12, 2020)

Latole said:


> Just one wire from this switch ?


I have a switch like that on my Pioneer chainsaw. The second terminal is internally grounded to the case so, when the switch is toggled the signal is grounded.


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## Latole (Aug 11, 2020)

Paul Running said:


> I have a switch like that on my Pioneer chainsaw. The second terminal is internally grounded to the case so, when the switch is toggled the signal is grounded.



Not this amp IMO 

As Loudtubes picture show


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## fogdart (Mar 22, 2017)

Latole said:


> IMO the switch is not working, one wire is missing.
> 
> View attachment 460108


It’s his patented “Placebo Effect”


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## Latole (Aug 11, 2020)

fogdart said:


> It’s his patented “Placebo Effect”


😂


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## Adcandour (Apr 21, 2013)

bluehugh2 said:


> Still waiting on J’s answer… but he appears to be lazy…


When I said he got back to me quickly, I forgot to mention that I showed him my tits.


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## bluehugh2 (Mar 10, 2006)

Definitive answer: 
(Thanks for all the input lads)…

“Hugh,
That switch is a bass cut. Forward towards the speaker is full range, pull it back to roll off some low end.
Best regards,
Jesse”


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## greco (Jul 15, 2007)

bluehugh2 said:


> Definitive answer:
> (Thanks for all the input lads)…
> 
> “Hugh,
> ...


@bluehugh2 You (and others whom you know here in the forum) have owned many, many various amps through time. 
Have you ever seen/heard of this feature in the past? Thanks


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## bluehugh2 (Mar 10, 2006)

Well, I’ve never seen a “bass cut” switch… but various tone control setups do achieve a version of this


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## Adcandour (Apr 21, 2013)

bluehugh2 said:


> Definitive answer:
> (Thanks for all the input lads)…
> 
> “Hugh,
> ...


tell me it was just coincidental that you got an answer right after I shared my tip.


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