My take on an SSS

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dorrisant
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Re: My take on an SSS

Post by dorrisant »

drew wrote:Put 10thTx on the case. Man dreams in ExpressSCH.
Exactly what I was thinking... gonna go look through the "Editable D-style Schematics" to see if he already did it.
Synchu
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Re: My take on an SSS

Post by Synchu »

mhartman wrote:
dorrisant wrote:Where is the associated schematic for this layout?
I was too lazy to make one. If someone wants to write it up, that would be very cool. This amp was a few years ago, I'm on to other ideas these days.
Still one of my top 2 amps by a mile (if not top 1 :))

Curious to see and hear what you're after now.

Niki
larsvictor
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Re: My take on an SSS

Post by larsvictor »

:D long rainy sunday afternoon...

Schematics corrected November 7th.

Lars
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Last edited by larsvictor on Mon Nov 07, 2016 4:51 pm, edited 2 times in total.
Bombacaototal
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Re: My take on an SSS

Post by Bombacaototal »

larsvictor wrote::D long rainy sunday afternoon...

It may contain errors.

Lars
Awesome!! Thanks a lot
Travis_HY
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Re: My take on an SSS

Post by Travis_HY »

larsvictor wrote::D long rainy sunday afternoon...

It may contain errors.

Lars
Very much appreciated! :D Thank you!
"Genius manifests itself. You got a hammer. You either build a Cathedral or you build a shithouse." - Carl Schroeder
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dorrisant
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Re: My take on an SSS

Post by dorrisant »

Thank you Lars!
"Education is what you're left with after you have forgotten what you have learned" - Enzo
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dorrisant
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Re: My take on an SSS

Post by dorrisant »

Synchu wrote: Still one of my top 2 amps by a mile (if not top 1 :))
What is the other on your list?
"Education is what you're left with after you have forgotten what you have learned" - Enzo
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mhartman
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Re: My take on an SSS

Post by mhartman »

larsvictor wrote::D long rainy sunday afternoon...

It may contain errors.

Lars
Nice work! Thank you. BTW, my original amp build on this circuit is still out on tour going strong.
Synchu
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Re: My take on an SSS

Post by Synchu »

dorrisant wrote:
Synchu wrote: Still one of my top 2 amps by a mile (if not top 1 :))
What is the other on your list?
The Komet 60.

Lars - thank you!

Niki
10thTx
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Re: My take on an SSS

Post by 10thTx »

Lars,

Would you please add your schematic (editable SCH) to the editable D-style thread in the Dumble files:

http://ampgarage.com/forum/viewtopic.ph ... 9&start=30

With respect, 10thtx
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dorrisant
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Re: My take on an SSS

Post by dorrisant »

Schematics from Lars have been edited and reposted...

You might want to grab the latest copy.

Thanks again Lars!
"Education is what you're left with after you have forgotten what you have learned" - Enzo
Bombacaototal
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Re: My take on an SSS

Post by Bombacaototal »

larsvictor wrote: Sun Nov 06, 2016 9:46 pm :D long rainy sunday afternoon...

Schematics corrected November 7th.

Lars
Hi Lars, I noticed the schematic is missing the lnfb on v2a which the layout has

Also the filter looks different from #002, where the .02uf ground meets the 820k

Which is the correct way?
SixStringBender
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Re: My take on an SSS

Post by SixStringBender »

Nice work mhartman. Not picking on you below because you followed Howard's design.

Shouldn't the negative voltage at the cathode of the CF between the PI and output tubes have at least three times the negative bias voltage for proper class AB2 operation? I know another power supply would need to be made, but for an amp of this magnatude wouldn't it be worth it?

Also for reliability. That much voltage from plate to cathode is over stressing that CF tube. A full wave, well filtered, low impedance power supply just for that tube would be much more optimal with only 320V, or so, across it. About +160V above ground and -160V below ground. This would also be more ideal for class AB2 operation. Easily obtainable from a small 120V-0-120V power tranny and a bipolar power supply with Pi filters. Or, better yet, a custom power tranny with a 120V-0-120V winding.
Travis_HY
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Re: My take on an SSS

Post by Travis_HY »

Hey y'all,

I was trying to figure this out without resurrecting this old thread but I think I have reached the pinnacle of my own confusion.

The issue is the Local Negative Feedback Loops being somewhat different from the layout compared to the schematic. Here's a break down of the schematic:

V1 (EQ & Filter circuits)
A - three-way switch using 4.7M with .047uF
B - three-way switch using 10M with .047uF

V2 (A. Reverb Send and B. Reverb Return)
A - none
B - none

V3 (Reverb Driver)
A&B - 4.7M with .047uF

V4 (A. Dry and B. Reverb Mixer)
A - 22M with .047uF
B - 22M with .1uF



When you compare these Local Negative Feedback Loops to the layout, there are a few discrepancies (*denotes the discrepancies):

V1 (EQ & Filter circuits)
A - three-way switch using 4.7M with .047uF
B - three-way switch using 10M with .047uF

V2 (A. Reverb Send and B. Reverb Return)
A - 10M with .01uF* (there is no loop whatsoever in the schematic)
B - none

V3 (Reverb Driver)
A&B - 4.7M with .047uF

V4 (A. Dry and B. Reverb Mixer)
A - 22M with .047uF
B - 22M with .01uF* (the schematic calls for a .1uF instead of a .01uF like the layout/photo)

Now when I look at the photos of the completed build, it appears that the layout is the accurate spec and the schematic is not; the schematic was made without the amplifier on hand. I would assume there would be more component value mistakes on the schematic than the layout because of this.

Any direction would be appreciated as I think other forum members might benefit from this being brought to their attention. As always, thank you Mike and all so much for such an incredible resource for info about these circuits; we'd all be by ourselves trying to figure it out if it weren't for Amp Garage. :D
"Genius manifests itself. You got a hammer. You either build a Cathedral or you build a shithouse." - Carl Schroeder
larsvictor
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Re: My take on an SSS

Post by larsvictor »

Hi,

Thanks to everyone who reviewed the schematics. I tried to fix all the errors you mentioned.
The current versions are here and in the "editable D-style schematics" -section.

Thanks
Lars
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