AMT - Legend Amp Series 2  [traced]

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Ice-9
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Post by Ice-9 »

ggedamed wrote:You're not talking about the thing that Burgs does with his left hand index, are you?
Hope you don't mind me insisting on this :cheers, the sound artifacts are really difficult to explain or even point to.
Well spotted, the little vibrato hammer type of thing he does, also at the 5.05 mark toggling of the pickup switch and it also looks like just before that he may just catch the vol knob.
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 phatt »

I don't mind if you insist,,, all good. :thumbsup
Between 5:03 and 5:04 there is a fast flurry of notes and there is a lot of mud (maybe the term is inter-modulation)

The P2 is even more pronounced

At 0:43 it spits for a split second on a bend up and again at 0:47 another fast riff,, spatters badly.

Just sayin,,That would bug me. :x
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Nicht Bernd
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Post by Nicht Bernd »

The pcb is far too big for a 1590BB. What kind of box do I need?

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Post by DimebuGG »

I made a through hole pcb of this for 1590BB type enclosure. Although it's already done, I need to take a look at it again before posting. 8)

What will be the necessary adjustments if 18-24V will be used to power this circuit?.
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Post by phatt »

DimebuGG wrote: What will be the necessary adjustments if 18-24V will be used to power this circuit?.
I'd guess,,,,,,,,,a complete redesign. :blackeye Which will likely achieve very little benefit.
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Post by bajaman »

they were designed for 9v dc - phatt is spot on with his comment - use the correct voltage for the correct response
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Post by J0K3RX »

I think they can use up to 12V... I wouldn't go a hair over +300VDC but, it might be fun to watch somebody else try! :twisted:

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Post by DimebuGG »

J0K3RX wrote: I wouldn't go a hair over +300VDC but, it might be fun to watch somebody else try! :twisted:
Oh yeah, will definitely try that.. :wink:
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Ice-9
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Post by Ice-9 »

Yeah.. I says 9-12v on the tin, and they sound bloody good so no point I changing the voltage.
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 DimebuGG »

Here it is..

Thanks to bajaman for allowing me to attach his schematic. :applause:
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AMT LegAmp2 PCB.pdf
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J0K3RX
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Post by J0K3RX »

DimebuGG wrote:Here it is..
Damn!! That is some crazy trace work!! Nice job!

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Post by J0K3RX »

Found these in the "guitar-gear.ru" forum.. posted by forum member mrubanoff :wink:
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P2pot_1B-circuit.PDF
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P2pot_1B-assembly.PDF
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P2-base_1B-circuit.PDF
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P2-base_1B-assy.PDF
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Ice-9
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Post by Ice-9 »

J0K3RX wrote:Found these in the "guitar-gear.ru" forum.. posted by forum member mrubanoff :wink:
I haven't had time to compare these against the traces me and Bajaman made, have you spotted any differences ? :popcorn:
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 J0K3RX »

Ice-9 wrote:
J0K3RX wrote:Found these in the "guitar-gear.ru" forum.. posted by forum member mrubanoff :wink:
I haven't had time to compare these against the traces me and Bajaman made, have you spotted any differences ? :popcorn:
Nope, just stumbled across them while looking at other stuff and though :hmmm: better grab these before they disappear into the abyss.. Funny though because I think mrubanoff was explaining a problem with the P1 and asking for help to find a resolution but, I could be wrong..? The translation was horrible at best.. Klingon language would probably have made more sense :scratch:

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Post by orcl2 »

Hi folks! Someone had tested this schem?

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Post by masramdhani »

Thanks bajaman for your schematic.

I made a E2 clone based on your schematic. I use it as a preamp pedal, so i'm not building the drive and the cabsim out. In my country, 2sk208 and 2sk30R is quite rare, so i'm using only 2N5458, J201, and J177. By changing the JFET,re-adjustment of the resistor value for the amplifier stage is needed. I use 1 10k multiturn trimpot to solve those problem especially on the drain resistor. So far the sounds is acceptable. But, i hear a slight of "fart" when the sounds fade out. Still working on it.

Anyway thanks guys :thumbsup :thumbsup :thumbsup

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Post by Statzern »

DimebuGG wrote:Here it is..

Thanks to bajaman for allowing me to attach his schematic. :applause:
Has anyone built this yet? I have the AMT E2 which I love and would love to build just the high gain sections for preamps, but this PCB is big! Would even fit in a 1590BB? Looks like barely from the measurements.

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Post by POTL »

I correctly understand that the p-channel Jfet(T5/T7/T9) for the offset of the n-channel Jfet(T4/T6/T8) but does not affect the sound?

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Post by mnemonic »

bajaman wrote:they were designed for 9v dc - phatt is spot on with his comment - use the correct voltage for the correct response
I was wondering this also, I like to experiment with different voltages, and often pedals will function differently at higher voltage. I can understand how some wouldn't like that change in response and would consider it 'sterile', but a lot of stuff tends to sound punchier to me at 18 volts.

There was mention earlier in the thread of some of the electrolytics being 25 volts, so if all of them were atleast 25 volts I would think the pedal would be fine at 18 volts, right? I googled the data sheets of the transistors and that is still well within their ratings.

I'll have to open up my R2 soon and check the cap voltages. It sounds great at 12 volts but now I'm curious.

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