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Hoffman Amps Forum image Author Topic: SIR #36 Mod Schematic - Help  (Read 12035 times)

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Offline valhala92

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SIR #36 Mod Schematic - Help
« on: April 18, 2014, 04:22:54 pm »
Hi,
does anyone have a good schematic or layout for SIR #36 mod? I wanna build one from scratch, I saw some videos on youtube but I can't find the schematic for them.
I really liked these:

staalhoofd: https://www.youtube.com/watch?v=sV1QYMGtDBQ
PuroMojo: https://www.youtube.com/watch?v=BKLHbu1PmZw
BRBS: https://www.youtube.com/watch?feature=player_embedded&v=ZipeR9ZI_-M

Thanks
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Offline thermion

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Re: SIR #36 Mod Schematic - Help
« Reply #1 on: April 18, 2014, 04:53:17 pm »

Offline valhala92

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Re: SIR #36 Mod Schematic - Help
« Reply #2 on: April 19, 2014, 09:59:42 am »
Check here, down in the posts:
http://marshallroadhouse.com/viewtopic.php?f=9&t=11336

thanks, which marshall amp is better for this mod?
The world is full of Kings and Queens
Who blind your eyes and steal your dreams
It's Heaven and Hell, oh well

Offline PRR

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Re: SIR #36 Mod Schematic - Help
« Reply #3 on: April 19, 2014, 11:40:25 pm »
> SIR #36 mod?

Did you even _try_ the SEARCH??

http://el34world.com/Forum/index.php?topic=2467.msg19114#msg19114

Offline valhala92

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Re: SIR #36 Mod Schematic - Help
« Reply #4 on: April 20, 2014, 01:35:09 am »
> SIR #36 mod?

Did you even _try_ the SEARCH??

http://el34world.com/Forum/index.php?topic=2467.msg19114#msg19114

yeah but I wanted to know which one is the best for the sounds I mentioned above
The world is full of Kings and Queens
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It's Heaven and Hell, oh well

Offline thermion

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Re: SIR #36 Mod Schematic - Help
« Reply #5 on: April 21, 2014, 02:47:26 pm »
jcm800 would be a good start

Offline Backwoods Joe

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Re: SIR #36 Mod Schematic - Help
« Reply #6 on: April 21, 2014, 07:50:33 pm »
What does SIR stand for? :dontknow:

Offline HotBluePlates

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Re: SIR #36 Mod Schematic - Help
« Reply #7 on: April 21, 2014, 08:43:42 pm »
What does SIR stand for? :dontknow:


It is a rehearsal space in L.A. They also rented out instruments and amps (especially for recording). IIRC, the amps were stenciled with stock numbers, hence "SIR #36" and "SIR #39".

Offline Backwoods Joe

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Re: SIR #36 Mod Schematic - Help
« Reply #8 on: April 22, 2014, 07:08:17 pm »
THX HBP, I always wondered about that.

Offline sluckey

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Re: SIR #36 Mod Schematic - Help
« Reply #9 on: April 22, 2014, 08:24:41 pm »
This may be of some interest. It's the Staalhoof mod into an 18 watt power amp.

     http://home.comcast.net/~seluckey/Aro_Project.pdf
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Ed_Chambley

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Re: SIR #36 Mod Schematic - Help
« Reply #10 on: April 23, 2014, 01:49:06 pm »
This may be of some interest. It's the Staalhoof mod into an 18 watt power amp.

     http://home.comcast.net/~seluckey/Aro_Project.pdf
I saw this the other day in some reading material a friend sent me.  Can you tell me a little more about it.  Maybe somewhere I could read a tad more about it.  I like playing my Marshall's out, but I cannot use them very much, especially at home.  I don't know what it is about El34's, but these amps just will not play quiet at all. 


Will this amp produce the old Plexi Marshall tone at a reasonable volume?


It looks very interesting.

Offline sluckey

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Re: SIR #36 Mod Schematic - Help
« Reply #11 on: April 23, 2014, 03:50:10 pm »
Here's the original thread.

     http://el34world.com/Forum/index.php?topic=8470.msg75974#msg75974

This looks like a hi gain buzzsaw to me. If you want a Plexi sound look at the November amp.

A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Tone Junkie

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Re: SIR #36 Mod Schematic - Help
« Reply #12 on: April 23, 2014, 06:45:23 pm »
Check here, down in the posts:
http://marshallroadhouse.com/viewtopic.php?f=9&t=11336

thanks, which marshall amp is better for this mod?
Here is the problem that I dont think you understand. You can have the exact schematic of the amp you heard on youtube and build it and find in person that it doesnt really sound like that at all. I know, I have  made that mistake myself . Now to the real issue your missing. things like transformers ,components ,speakers, guitars pickups , along with even the type of speaker box you have will make a huge differance in sound. you have to learn how to tweek whats in front of you when your close to get the exact sound. I have found that even tweeking the NFB circuit to match the speakers and pickups make a huge differance in the sound of the amp. you must take all these things into consideration my friend. Its not as easy as which circuit is best to make this type of sound.
Bill

Offline Jack1962

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Re: SIR #36 Mod Schematic - Help
« Reply #13 on: April 27, 2014, 10:59:24 am »
do a search for the AFD layout Ceritone has a kit for that amp I would google search with the keywords Ceritone AFD layout. here are the ones I have.
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