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DIY Stompboxes => Building your own stompbox => Topic started by: Govmnt_Lacky on November 24, 2012, 06:55:54 PM

Title: SansAmp GT2 w/ onboard Alco switches
Post by: Govmnt_Lacky on November 24, 2012, 06:55:54 PM
I know that I asked about this forever ago but, I figured I would try again  :-\

Anyone happen to have or be able to link to a PCB layout of the SansAmp GT2 with the Alco switches onboard the PCB?

I have tried contacting the original forum member that posted the layout (it has since disappeared) but there has never been a reply.

Hoping for a miracle at this point  :icon_eek:
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: Ronan on November 24, 2012, 07:42:33 PM
I did a layout for a simplified GT2 for the turkey day comp. Minimal to no switches, you can select your options before building. The mic switch is not required if you are using it as a normal pedal, 2 of the 3 positions give a mid cut which is good if you want to record directly from it into a soundcard, or if you like the metal mid-scooped sound. My layout does not include the mid scoop option or the Fender clean sound option either. The gain and amp type can be preset with component values. Can post layout and schem if you want.

Probably not what you want, but thought I'd throw it in, you never know.
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: Govmnt_Lacky on November 24, 2012, 07:52:16 PM
@Ian

I appreciate the offer. I used to have one of these and I have missed it since  :'(

I happen to have like 5 of the Alco switches laying around and I know they can be used to build this BUT, I just dont want to hassle with the offboard wiring nightmare. This prompted me to search for a layout with onboard switches. Low and behold, I found a post by bleubleu with the exact thing I was looking for but sadly, the links were long gone and apparently.... so is the person who posted them  :-\

I really want to build a direct clone but it is looking like no one happened to save that layout. This is my last ditch attempt to try to get a copy of it before I put it on the long, long, long list of layouts that I need to do!!!  :o
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: Ronan on November 24, 2012, 08:16:39 PM
I guess you know the Behringer TM300 is a copy. Cheap too.
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: Govmnt_Lacky on November 24, 2012, 08:21:19 PM
Quote from: Ronan on November 24, 2012, 08:16:39 PM
I guess you know the Behringer TM300 is a copy. Cheap too.

Thats no fun!!  :icon_wink:

DIY forever!!!

Plus... I'm very, very cheap!
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: karter2000 on November 24, 2012, 09:08:22 PM
Quote from: Ronan on November 24, 2012, 07:42:33 PM
I did a layout for a simplified GT2 for the turkey day comp. Minimal to no switches, you can select your options before building. The mic switch is not required if you are using it as a normal pedal, 2 of the 3 positions give a mid cut which is good if you want to record directly from it into a soundcard, or if you like the metal mid-scooped sound. My layout does not include the mid scoop option or the Fender clean sound option either. The gain and amp type can be preset with component values. Can post layout and schem if you want.

Probably not what you want, but thought I'd throw it in, you never know.

I'd be super interested in that!!!! I love the GT2 as a bass distortion, but only need a few of the settings.
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: Ronan on November 24, 2012, 10:56:07 PM
Verified by me, but not built by anyone else. I love the gt2 circuit, seems very good at "old school" distortion sound (80's rock).

(http://i198.photobucket.com/albums/aa160/birdy81260/th_Rule8schematic2.jpg) (http://s198.photobucket.com/albums/aa160/birdy81260/Rule8schematic2.jpg)

(http://i198.photobucket.com/albums/aa160/birdy81260/th_Rule8input9buildoverlay.gif) (http://s198.photobucket.com/albums/aa160/birdy81260/Rule8input9buildoverlay.gif)

toner transfer (https://dl.dropbox.com/u/61170900/Rule8%20input%208%20toner%20transfer.pdf)

Edit: just noticed the pin spacing for the 2u2 cap between the VOL and GAIN pots is 0.2" instead of 0.1".
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: J0K3RX on November 25, 2012, 12:08:59 AM
You mean this??
http://www.diystompboxes.com/smfforum/index.php?topic=38425.0

Didn't know the GT2 had Alco switches?


Another one here
http://www.diystompboxes.com/smfforum/index.php?topic=36179.60

I actually loved the sansamp classic, way better than the GT2 in my opinion! Not sure how these stack up to the real thing though???
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: Ronan on November 25, 2012, 12:25:55 AM
I have a real GT2 for comparison on a temporary basis, the first one without SMD components. The clones are very close, but not exactly the same. I wouldn't care if I used a real one, a TM300, or a DIY clone, they are all capable units. I will have to give the real gt2 back soon, I won't miss it.
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: J0K3RX on November 25, 2012, 12:49:11 AM
Quote from: Ronan on November 25, 2012, 12:25:55 AM
I have a real GT2 for comparison on a temporary basis, the first one without SMD components. The clones are very close, but not exactly the same. I wouldn't care if I used a real one, a TM300, or a DIY clone, they are all capable units. I will have to give the real gt2 back soon, I won't miss it.

Yeah, I bought a GT2 thinking that it would be like the sansamp classic and they are nowhere close! I had my Classic stolen years ago and never bought another one, yet. The classic has some mojo and Andrew Barta still uses the same process to make the classic on the ceramic substrate that he used back in the 80's... I have a PSA-1 right now and I would trade it for a Classic in a heart beat!

Interesting read.
http://www.soundonsound.com/sos/1996_articles/jun96/andrewbarta.html
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: Ronan on November 25, 2012, 02:23:32 AM
I think with the gt2, that it may have been misunderstood right from the start, the switches can be misleading at best. The 3 position mic switch corresponds to straight, mid cut 1 and mid cut 2 (with mid cut 2 being at a higher freq than mid cut 1.) The off-axis/center/classic mic description makes absolutely no sense to me. Then you have the clean/hi-gain/hot-wired switch. If you want it to sound something like a real tube amp then you set it to clean. The other two positions destroy the sound IMO. The third switch makes more sense, Fender/Marshall/Boogie. The Marshall gets a big gain boost and bass roll-off. The Boogie gets less bass roll-off and less gain.

I guess I am lucky I found a dirt box I am happy with.
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: J0K3RX on November 29, 2012, 06:42:19 PM
Found this while looking for other stuff... You have to sign up for the forum to download...
http://www.elektroda.pl/rtvforum/viewtopic.php?t=2062128&mark=topic&sid=8ee03822e9012bdc651a850cd836c119

Also another here with on board switches and not SMT... I have the Sprint file if anybody wants it or you can download it from the link
http://guitar-gear.ru/forum/topic/122-sans-amp-gt-2/page__st__1080
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: Ronan on November 29, 2012, 08:03:04 PM
I'm getting the impression that if you can't find something, Jim, then no-one can :)
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: J0K3RX on November 29, 2012, 10:59:56 PM
Quote from: Ronan on November 29, 2012, 08:03:04 PM
I'm getting the impression that if you can't find something, Jim, then no-one can :)

;D Ian lol, I just stumbled on that stuff and remembered that Govmnt_Lacky was looking for something like this... Not sure if this is like what he had in mind but it really looks well designed to me!

Here is a better link to the entire project... The download links are hard to see on this page but the link to the board layout files are right under the picture of the board layout.
http://www.guitar-gear.ru/index.php?p=proj&id=57

I would build one of these myself and I do think they sound really damn good! But, I can justify all of the work and effort needed for this build since I picked up a 15watt V-TONE GM108 practice amp for $10 at a garage sale which looks and sounds like an exact copy of the GT2 pedal... I see them all the time on craigslist for next to nothing... But still is a great pedal, not as good as the Classic but really good none the less.
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: nomorebetts on December 12, 2012, 05:54:30 PM
I have a layout for on board rotary switches and pots for a 1590BB that is about 80% complete.
I abandoned work on it as I didn't have a piece of copper clad that was big enough and the friend who I was building it for was getting impatient so I used the Tonepad pcb.

Think I'll finish it up and post it for others who might be interested.
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: nomorebetts on December 29, 2012, 05:55:37 AM
Quote from: nomorebetts on December 12, 2012, 05:54:30 PM
I have a layout for on board rotary switches and pots for a 1590BB that is about 80% complete.
I abandoned work on it as I didn't have a piece of copper clad that was big enough and the friend who I was building it for was getting impatient so I used the Tonepad pcb.

Think I'll finish it up and post it for others who might be interested.

Finished and posted in the layouts section.    :)

http://www.diystompboxes.com/smfforum/index.php?topic=100631.0

It shouldn't take too much effort to alter it for the alco switch... just say the word and I'll be happy to do it.
Title: Re: SansAmp GT2 w/ onboard Alco switches
Post by: J0K3RX on December 29, 2012, 08:29:58 AM
Quote from: nomorebetts on December 29, 2012, 05:55:37 AM
Quote from: nomorebetts on December 12, 2012, 05:54:30 PM
I have a layout for on board rotary switches and pots for a 1590BB that is about 80% complete.
I abandoned work on it as I didn't have a piece of copper clad that was big enough and the friend who I was building it for was getting impatient so I used the Tonepad pcb.

Think I'll finish it up and post it for others who might be interested.

Finished and posted in the layouts section.    :)

http://www.diystompboxes.com/smfforum/index.php?topic=100631.0

It shouldn't take too much effort to alter it for the alco switch... just say the word and I'll be happy to do it.


Holy Sh!t!!!! :o  That is wicked bad ass!! Gteat job! :icon_twisted: