AMT Electronics - S1 Legend series  [schematic]

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Ice-9
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Post by Ice-9 »

Here is an updated schematic to look over, I have tidied it up a bit so it is more accurate. There is still a couple of things to add to the schematic but this is the main audio path not including the cab sim.
R40 is a trim pot that has the centre pin connected to the power rail and one wiper end connects to R18 to the Drain of VT7, the other wiper end goes to a voltage divider to bias VT2. VT2 goes of to the cab sim circuit which I will look at next.

AMT S1 legend ver 1 schematic below.
Attachments
AMT S1 legend schematic ver1.jpg
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

Ice-9
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Post by Ice-9 »

Ice-9 wrote:Here is an updated schematic to look over, I have tidied it up a bit so it is more accurate. There is still a couple of things to add to the schematic but this is the main audio path not including the cab sim.
R40 is a trim pot that has the centre pin connected to the power rail and one wiper end connects to R18 to the Drain of VT7, the other wiper end goes to a voltage divider to bias VT2. VT2 goes of to the cab sim circuit which I will look at next.

AMT S1 legend ver 1 schematic below.
Sorry typo above , where i say R40 highlighted in red it's meant to read R13
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

Ice-9
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Post by Ice-9 »

Here is the final schematic of the AMT S1 legend, all fets in the schematic are 2SK208-R (Thanks for the info from KMG and help from marshmellow on this)I have left out the bypass and LED indicator along with the cab sim from the schematic. I have traced out the cab sim so if anyone would like to see it or check it i can post that.

Most component values are in the schematic although there are some cap values missing, when I can I will measure them with a meter and post the complete component list.

AMT S1 Schematic.
Attachments
amt s1 final 1.jpg
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

Mbas974
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Post by Mbas974 »

Great job man !!
is it made with Eagle cad ? If so... any chance to get schematic file ( .sch ) file too ?

Now..... it's time to understand the difference with other Legend pedals :horsey: I think it will be just a cap and resitor values matter.

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Post by jymaze »

Thanks a lot for that schematic!

I would be interested in the cab sim portion of it. And I am sure I am not the only one!

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Post by Ihunda »

Thanks, thanks, thanks!
I am also looking forward to the cab sim part!
It it a simple 5Khz low pass or not ;) ?

Ice-9
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Post by Ice-9 »

Mbas974 wrote:Great job man !!
is it made with Eagle cad ? If so... any chance to get schematic file ( .sch ) file too ?
I have made the schematic with Diptrace. :secret: Download the free version of diptrace though and I will post the schematic file for you.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

Ice-9
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Post by Ice-9 »

Ihunda wrote:Thanks, thanks, thanks!
I am also looking forward to the cab sim part!
It it a simple 5Khz low pass or not ;) ?
there is a little more to it, but it is an active filter, I have made a mistake in tracing the sim cab so will have to check it before posting. :scratch:
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

roseblood11
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Post by roseblood11 »

Is it the version that he describes on the website?
http://www.amtelectronics.com/support/a ... tor_kempf/

Ice-9
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Post by Ice-9 »

roseblood11 wrote:Is it the version that he describes on the website?
http://www.amtelectronics.com/support/a ... tor_kempf/
It has some similarities but is not as complex as the website version. That link will help in finishing the trace though.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

Ice-9
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Post by Ice-9 »

I finally got back to this one to finish the cab sim part of the circuit.

Here is the complete schematic for the full pedal inc cabsim, the input signal to the cab sim is taken from the output jack of the effect.
Attachments
AMT1 S1 legend with cab-sim.jpg
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

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J0K3RX
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Post by J0K3RX »

Anybody build one of these?

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Post by Ice-9 »

J0K3RX wrote:Anybody build one of these?
I got the 2sk208's and the bat54's but haven't had a chance to build it yet , but the schematic has been checked and retraced about 4 times so can say it's verified schematic wise but not built. Those components only seem to be available as smd parts though.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

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Post by lugburz2000 »

Hi
I have an Amt B1 pedal and here are some Pics
Attachments
pcb Bottom 01
pcb Bottom 01
Pcb Bottom 02
Pcb Bottom 02
Pcb Top
Pcb Top
Pots 01
Pots 01
Pots 02
Pots 02

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Post by lugburz2000 »

and here is the schematic, without Cabinet simulation, and with DC Measurements :
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B1 Pedal Schematic with DC Values.png

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Post by lugburz2000 »

sorry for subject in previous message.. is not S1 schematic but B1
perhaps it would have been more correct to have open new thread.
sorry.

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Post by lugburz2000 »

On Pcb pictures "bottom 01" and "bottom 02" you can see a yellow wire bridging a track.
This is because when i was desoldering components to better following the circuit for drawing
the schematic, then i accidentally burnt off one solder pad.

Ice-9
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Post by Ice-9 »

lugburz2000 wrote:On Pcb pictures "bottom 01" and "bottom 02" you can see a yellow wire bridging a track.
This is because when i was desoldering components to better following the circuit for drawing
the schematic, then i accidentally burnt off one solder pad.
Thanks for posting the B1 schematic, I also have a P1 and the circuit board is the same as for the B1 except that all the missing components on the B1 pcb are soldered in place on the P1. So it's basically the same circuit with more gain stages in there, and probs some different value comonents as well.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

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Post by Sikor »

A little bit OT:
AMT has just presented new series of amp-simulation pedals.
They have extended the range of simulated amps to 10 or so :)
And all of them have been revoiced and are using the same "technology" as their new SS amp.

I have made some pictures at Musikmesse (no guts shots yet ;))

Image
Image
Practice cures most tone issues - John Suhr
--
My Musikmesse 2012 gallery and more...

Ice-9
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Post by Ice-9 »

Thanks Sikor for the pics, can't wait to see some of the gut shots of these. :wink: Mm 2 chanl clean/dirty preamps in a pedal size. I just love the stuff AMT are doing.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

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