JHS - AT (Andy Timmons) Signature Drive  [traced]

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JHS - AT (Andy Timmons) Signature Drive  [traced]

Postby bugg » 15 Dec 2017, 20:02

AngryAndySchematic.png

PCBs are available here: http://www.pedalpcb.com/product/angryandy/

AngryAndy-510x600.jpg
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dv8r601 (16 Dec 2017, 02:10), Groovenut (16 Dec 2017, 15:39), Intripped (08 Oct 2019, 17:50), jt (16 Dec 2017, 16:43), karul (15 Dec 2017, 23:19), modman (02 Sep 2019, 23:25)
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby roseblood11 » 15 Dec 2017, 22:36

The toggle is a on/off/on, so no clipping diodes in middle position?

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Re: JHS - AT (Andy Timmons) Signature Drive

Postby roseblood11 » 15 Dec 2017, 22:38

Hast du in deiner Finanzplanung ein Plug In für Drums mit drin? Hilft einem sehr beim Ideen sammeln... Ich nutze zB EZdrummer, weil man da schnell im Plug-In eine Songstruktur bauen kann und dann mit einem Click in die DAW übernehmen.
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby bugg » 16 Dec 2017, 00:22

roseblood11 wrote:The toggle is a on/off/on, so no clipping diodes in middle position?


I do believe that is correct. This should correspond to the 100W mode, described as "cleaner, loud".

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Re: JHS - AT (Andy Timmons) Signature Drive

Postby Scruffie » 16 Dec 2017, 02:51

roseblood11 wrote:Hast du in deiner Finanzplanung ein Plug In für Drums mit drin? Hilft einem sehr beim Ideen sammeln... Ich nutze zB EZdrummer, weil man da schnell im Plug-In eine Songstruktur bauen kann und dann mit einem Click in die DAW übernehmen.

Mein Deutsch ist schlecht aber das ist nicht verwandt? :scratch: :mrgreen:
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby Groovenut » 16 Dec 2017, 04:43

bugg wrote:
roseblood11 wrote:The toggle is a on/off/on, so no clipping diodes in middle position?


I do believe that is correct. This should correspond to the 100W mode, described as "cleaner, loud".

I was under the impression that the louder setting were the LEDs , the lowest setting were the Schotky's and the middle setting were mosfets.
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby bugg » 16 Dec 2017, 13:17

Groovenut wrote:
bugg wrote:
roseblood11 wrote:The toggle is a on/off/on, so no clipping diodes in middle position?


I do believe that is correct. This should correspond to the 100W mode, described as "cleaner, loud".

I was under the impression that the louder setting were the LEDs , the lowest setting were the Schotky's and the middle setting were mosfets.


There are no mosfets in the thing. I know the Madbean Turnabout has them, but the AT doesn't.
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby Groovenut » 16 Dec 2017, 15:35

bugg wrote:
Groovenut wrote:
bugg wrote:
roseblood11 wrote:The toggle is a on/off/on, so no clipping diodes in middle position?


I do believe that is correct. This should correspond to the 100W mode, described as "cleaner, loud".

I was under the impression that the louder setting were the LEDs , the lowest setting were the Schotky's and the middle setting were mosfets.


There are no mosfets in the thing. I know the Madbean Turnabout has them, but the AT doesn't.

Ah I see. Very interesting. Thanks for the info!
There's an assembled board on ebay that claims to be JHS @ that seems to bear this out in the pics.
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby alexradium » 16 Dec 2017, 15:37

OMG its amazing,what a genius!

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Re: JHS - AT (Andy Timmons) Signature Drive

Postby bugg » 16 Dec 2017, 16:40

I don't have the original in-hand anymore but this is a fairly good pic of the PCB.

The two components at the bottom (D201 and Q200) are part of the LED switching. There are no components on the other side of the board.

jhspedals_at_003.jpg
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby Manfred » 16 Dec 2017, 22:42

Scruffie wrote:
roseblood11 wrote:Hast du in deiner Finanzplanung ein Plug In für Drums mit drin? Hilft einem sehr beim Ideen sammeln... Ich nutze zB EZdrummer, weil man da schnell im Plug-In eine Songstruktur bauen kann und dann mit einem Click in die DAW übernehmen.

Mein Deutsch ist schlecht aber das ist nicht verwandt? :scratch: :mrgreen:


Miss the point, I guess text insert by mistake.
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby roseblood11 » 17 Dec 2017, 01:26

Ups, I wanted to post that to another forum. Crappy small smartphone display...
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby shredgd » 06 Oct 2019, 08:54

The EQ is a linear (B) pot like the Air pot. I am sure because after endless researches I found a picture of the top side of a AT pedal circuit board, showing the B10k pot.

Have a nice day!
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby Adam_MD » 06 Oct 2019, 10:12

Has anyone done a vero layout for this yet? So far I've only seen the Madbean Turnabout.
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby Ben N » 06 Oct 2019, 13:27

Should be very easy to convert the one to the other.
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby Ichabod_Crane » 07 Oct 2019, 08:29

Comparing the schematic of the Madbean Turnabout and the Pedal PCB version of the JHS - AT the differences are minimal. In the Pedal PCB the coupling cap after the second opamp stage is 2.2uF and not 1uF, and the Volume pot is log and not linear.
And of course the clipping, the central position is with Mosfet in the Madbean Turnabout (a sort of OCD style, I guess). While in the Pedal PCB is with any diode or anything. I guess the original AT is like the Pedal PCB.
I would like to build a JHS AT, but I have some doubts about the schematic.

About the EQ pot: rev log vs linear. I can't say what original pedal mount.
shredgd wrote:The EQ is a linear (B) pot like the Air pot. I am sure because after endless researches I found a picture of the top side of a AT pedal circuit board, showing the B10k pot.

I'd like to see this picture, too. Anyway, with my emulator probably a reverse log as EQ should give a more balanced response.

There's a lot of discussions about the difference between the AT and the Crunch Box, and in some picture we can see in the AT pedal just a third extra 100nF cap, one after the gain pot, one in the power filter as in the Crunch Box. Everybody says that this extra 100nF cap is across the ground and in parallel to the 22nF in the tone section. But Pedal PCB and Madbean Turnabout doens't have it.
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby shredgd » 08 Oct 2019, 16:38

Ichabod_Crane wrote:About the EQ pot: rev log vs linear. I can't say what original pedal mount.
shredgd wrote:The EQ is a linear (B) pot like the Air pot. I am sure because after endless researches I found a picture of the top side of a AT pedal circuit board, showing the B10k pot.

I'd like to see this picture, too. Anyway, with my emulator probably a reverse log as EQ should give a more balanced response.


Here you have it!
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby shredgd » 08 Oct 2019, 16:42

Ichabod_Crane wrote:There's a lot of discussions about the difference between the AT and the Crunch Box, and in some picture we can see in the AT pedal just a third extra 100nF cap, one after the gain pot, one in the power filter as in the Crunch Box. Everybody says that this extra 100nF cap is across the ground and in parallel to the 22nF in the tone section. But Pedal PCB and Madbean Turnabout doens't have it.


I've already written in another forum that this "extra 100nf cap" is only a voltage stabilizer for the opamp, placed between V+ and ground, which is a good practice to have very close to the opamp. The cap in the tone section is really only the 22nf.

Giulio

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Re: JHS - AT (Andy Timmons) Signature Drive

Postby Ichabod_Crane » 09 Oct 2019, 08:08

Thank shredgd for the picture. It's really clear that the EQ is a linear pot. I'm curious to try a rev log, too.

Thank you Giulio, I missed your information in this other forum. Then, this 100nF you mean is a bit like the other in the power filter? (C10 in the Pedal PCB schematic posted above).
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Re: JHS - AT (Andy Timmons) Signature Drive

Postby shredgd » 09 Oct 2019, 16:58

Ichabod_Crane wrote:Then, this 100nF you mean is a bit like the other in the power filter? (C10 in the Pedal PCB schematic posted above).


Exactly. Compare this Angry Charlie guts picture (C9):
IMG_1064.JPG


with this Sweet Tea guts picture (Angry Charlie part of the circuit on the right), where you have an SMD cap in the same place, very close to the opamp. In both layouts that cap is far from the 22nf caps of the tone section.
IMG_0432.JPG
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