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Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 00:59
by jymaze
Ok Jok3rx, I'll try to check that layout this week.

Gegedamed, me neither, I don't hear any sponginess in that video clip! Super tight! If you want to hear sponginess, try a Big Muff Pi, that is sponginess.

Like Bajaman said, bypass you first voltage reference with a 22u cap. It is very important because without that you just introduced a very complex multi-feedback loop in the circuit!!!

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 01:28
by J0K3RX
jymaze wrote:Ok Jok3rx, I'll try to check that layout this week.

Gegedamed, me neither, I don't hear any sponginess in that video clip! Super tight! If you want to hear sponginess, try a Big Muff Pi, that is sponginess.

Like Bajaman said, bypass you first voltage reference with a 22u cap. It is very important because without that you just introduced a very complex multi-feedback loop in the circuit!!!

pakrat has it etched and half way populated... Apparently he has deep faith in my layouts? Poor guy has had so many duds with my stuff... :roll:

In my opinion you have to have some level of sponginess (not much) or it will be very unforgiving when you play lead... It's a fine line!

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 01:40
by jymaze
In my opinion you have to have some level of sponginess (not much) or it will be very unforgiving when you play lead... It's a fine line!
Agreed, and that is what I was wondering too... Is the tight metal any good for lead? It sounds like a rhythm oriented pedal to me.

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 01:47
by J0K3RX
jymaze wrote:
In my opinion you have to have some level of sponginess (not much) or it will be very unforgiving when you play lead... It's a fine line!
Agreed, and that is what I was wondering too... Is the tight metal any good for lead? It sounds like a rhythm oriented pedal to me.
Well, I only played it briefly (5 min) before I ripped it to pieces but, it wasn't too bad for leads...

For myself it would be nice to have the option of a tight control externally foot operated like a volume pedal for leads and rhythm or, buy a tight rock and rip
it to pieces and trace it :lol: I think that one is better for leads...

I wonder what different opamps will do say like the 4580's??

Skip to 3:13 and hear them both together... Is it just me or does that guy talking look like Weird Al? :lol:

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 05:10
by The G
bajaman wrote:It may help if you bypass the 150k resistor with a 22uf electro, if you use this simplified bias scheme :wink:
cheers
bajaman
Thanks, Bajaman, I'll try it before the LM317L. I tried first with as few modifications as possible from the schematics in this thread.
J0K3RX wrote:[...]
I wonder what different opamps will do say like the 4580's??
[...]
I'll try that too. I also have some LM4562s :lol:.

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 13:53
by The G
I really love breadboards - you can test anything in an instant.
I'd like to report that I tried it at 18V and all artifacts/sponginess/flabbines/whatever are gone, except those from the noise gate diodes closing/opening. I'll admit it is now on par with my YAJFET AMT/Black Forest style distortion. It has a really nice grind in it, maybe because of the crossover distortion in the noise gate.
I'll have to put the gate switch in (right now is always on).
I think I'll move the GAIN control on IC1B to see what kind of overdrive can it make. And maybe put it through a cabsim.

PCB-wise (layout-wise), I think the main issue that need to be dealt with will be the oscillations started from close signal tracks. True-bypass is a real feat on something with this much gain.

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 14:02
by jymaze
What is your YAJFET? Do you mind sharing the schematics?

It would be cool!

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 15:05
by jymaze
Jok3rx,

Your single layer layout is very good. I am about 100% sure it is correct, except those 3 points:

1) Like Bajaman said, D5 is floating
2) The ground pad just above the +9V pad should be connected to the ground track
3) I would try to make the ground track thicker than a normal track wherever possible since it is a long one
4) I forgot 1 resistor when tracing and it is a 100k resistor from the Output pad to ground (to avoid pops). Schematic should be updated in consequence.

That is it! Now, would someone etch me one please? :D

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 17:13
by The G
jymaze wrote:What is your YAJFET? Do you mind sharing the schematics?
It would be cool!
The full name is YAJFETD = Yet Another Junction Field Effect Transistor (JFET) Distortion :lol:.
It's nothing new by any means. I said it before, it is the usual Dr. Boogie style chain of single JFET stages and it differs from Black Forest in minor details, both being started by the AMT L1 thread.
As the schematic itself is nothing to write home, I'll start a thread (you know I promised) with a well known schematic (maybe Black Forest :lol:) and change it step-by-step according to my parts, tools and taste - beginner style, documenting and testing every step. The thread will result in a schematic and a PCB.

Re: Amptweaker - Tight Metal  [traced]

Posted: 03 Jun 2013, 20:29
by bajaman
tight metal -3g.sch
(117.88 KiB) Downloaded 234 times
TM schem 3g.png
new corrected schematic with 100k fitted at output :wink:

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 20:32
by rcustoms
hi guys ,my friend jim request to me another option to this great pedal ,in my version ,i use one quad op amp tl 074 and only one tl 072 ic.all pots and switches are on board.please verified .
i double checked ,and i think is ok but this layout is a really headache.
enjoy
ARMORED.pdf
(176.58 KiB) Downloaded 456 times

Re: Amptweaker - Tight Metal

Posted: 03 Jun 2013, 21:36
by apollomusicservice
rcustoms wrote:hi guys ,my friend jim request to me another option to this great pedal ,in my version ,i use one quad op amp tl 074 and only one tl 072 ic.all pots and switches are on board.please verified .
i double checked ,and i think is ok but this layout is a really headache.
enjoy
ARMORED.pdf
On your schem C3 should be 33n, C12- 100p, C19-22n, C8-C11? (duplicated) 8)

Re: Amptweaker - Tight Metal

Posted: 04 Jun 2013, 00:49
by rcustoms
Ok here we go again, now with 1590BB enclosure layout
ARMORED 1590BB.jpg
and the pdf correction
ARMORED.pdf
(166.73 KiB) Downloaded 422 times
rcustoms :D

Re: Amptweaker - Tight Metal

Posted: 04 Jun 2013, 02:12
by bajaman
Been agonising over that bloody DC socket connection, the 47 ohm resistor (470J) and series 1N4007 diode connection etc.
The Amptweaker manual clearly states that the four control illuminating leds only light up when using an external DC power supply NOT when using a battery. Took me a wee while trying to figure out how this is done and the solution is elegantly simple :wink: . Here is how this is achieved :secret:
The cathode of the last led in the series chain connects to the +9v battery terminal - it is also connected to the switch contact terminal (where the +9v battery lead is normally connected) AND the centre pin terminal of the DC socket :!:
ALSO connected to these two terminals is the cathode of the 1N4007 diode (the anode of this diode is then connected to the 47 ohm 1W resistor and this is then connected to the ring terminal of the input jack socket ).
The remaining DC socket terminal is then connected to the + 9V power rail main filter capacitor, op amp #8 pins and anode of the first led in the series chain, etc.
Brilliant :thumbsup

cheers
bajaman

Re: Amptweaker - Tight Metal

Posted: 04 Jun 2013, 02:41
by jymaze
Hey RC,

What software do you use to make your layouts? It looks nice!

Re: Amptweaker - Tight Metal

Posted: 04 Jun 2013, 03:50
by rcustoms
jymaze wrote:Hey RC,

What software do you use to make your layouts? It looks nice!
I use eagle cad v 6.3 pro, then i create a pdf file with each part(pcb,layout,parts and schematics)and then open each pdf file with corel draw x6 and put together in one layout for guitar effects parts layout(like knobs,switches ,pots etc.) i use a pedal effects builder vector parts ,if you or anybody need some help ,i be glad to cooperate just (PM) :thumbsup

Re: Amptweaker - Tight Metal

Posted: 04 Jun 2013, 04:07
by J0K3RX
rcustoms wrote:
jymaze wrote:Hey RC,

What software do you use to make your layouts? It looks nice!
I use eagle cad v 6.3 pro, then i create a pdf file with each part(pcb,layout,parts and schematics)and then open each pdf file with corel draw x6 and put together in one layout for guitar effects parts layout(like knobs,switches ,pots etc.) i use a pedal effects builder vector parts ,if you or anybody need some help ,i be glad to cooperate just (PM) :thumbsup
I love that layout! And you used the TL074! Excellent work!! :applause:

Re: Amptweaker - Tight Metal

Posted: 04 Jun 2013, 04:43
by J0K3RX
Rafael,

Do you think you can put the ARMORED transfer only into scaled format in a pdf? I can't print it to scale in your pdf..?

Thanks,
~ Jim

Re: Amptweaker - Tight Metal

Posted: 04 Jun 2013, 05:03
by The G
ARMORED_cropped_no-schematic.pdf
(137.3 KiB) Downloaded 415 times

Re: Amptweaker - Tight Metal

Posted: 04 Jun 2013, 05:45
by rcustoms
J0K3RX wrote:Rafael,

Do you think you can put the ARMORED transfer only into scaled format in a pdf? I can't print it to scale in your pdf..?

Thanks,
~ Jim
you got it
armored scale.pdf
(35.5 KiB) Downloaded 463 times