Double SSS Preamp (inspired by 004&005)

[martin manning]

Another essential part of the revised filters I proposed is relocating the 3n cap going to ground to the high selector switch pole. The hand drawn schematic is in error there, I believe, and the value of that cap also affects the high-low balance. The response is centered around 400 Hz, and both the high and low filters extend into the mid range.

[ElectronAvalanche]

Another essential part of the revised filters I proposed is relocating the 3n cap going to ground to the high selector switch pole. The hand drawn schematic is in error there, I believe, and the value of that cap also affects the high-low balance. The response is centered around 400 Hz, and both the high and low filters extend into the mid range.

Hi Martin,

Are you refering to my handdrawn schematic? In my schematic for both the 004 and the 005 the 0.0033/0.0022 caps are connected to the high filter switch and then to ground.

Here is a pic clarifying the connection.

IMG_0477.jpeg

Best Regards and thank you for pointing this out.

Electron

[martin manning]

No, I was referring to the hand-drawn SSS 002 schematic with Japanese writing.

[martin manning]

PS, the 2n2 in your 005 vs.the 3n3 in your 004 effectively moves the whole high filter up one click.

[ElectronAvalanche]

PS, the 2n2 in your 005 vs.the 3n3 in your 004 effectively moves the whole high filter up one click.

Indeed and thank you for pointing this out. The difference between 2n2 and 3n3 is quite distinct. I later added a 1n in parallel to the 2n2 but I forgot to correct this in the schematic. Tonight I also changed the 0.68 uF cathode bypass cap in the 005 to a 4u7 and quite like that for the moment.

@rootz:

I might be tempted to go all in for your filter setup but will play the preamp as is for a while.

BTW: obviously we are all interpreting the circuit and tweaking it to our likes.

I find the original filters of my standalone 002 not as useful as the tweaked Manning version in my Double SSS preamp. Question is if the 002 handdrawn schematic simply has some errors (yet the Dumblelland video on YT also shows the muffled sound of the 3n3 not being connected to the high filter buss) or if Dumble tweaked the amp for the customer (although I would guess the customer would have also preferred an even function of the filters). We will never know.

I also think that inside pics of 005 and 004 will never surface so I guess we are left with guess-work (which is part of the fun) and trial and error.

Electron

[martin manning]

I had forgotten about the video that exhibited the big change on the first high selector step (it's six years ago now!), which suggests that that bit of the hand drawn schematic is correct. I agree that even steps over a usable range would be the preferred functionality for most, and I see nothing wrong with improving upon what Dumble did where possible.

[ViperDoc]

Wow, those look nice and clean. Nice job!

Where and how do you primarily use these, in a studio or live setting?

Cheers.

[GPD]

Very Sexy!

Love your rack mount enclosures of choice...some of the highest quality I've ever seen outside of military data center rack mount gear. Out of curiosity...have you measured the S/N ratio in any of these preamps at higher gain levels? I'm curious as to how much hum is getting induced into the preamp circuitry from that in chassis mounted toroidal transformer. Might be negligible but you never know until you build it .

Which of course you have.

[ElectronAvalanche]

Wow, those look nice and clean. Nice job!

Where and how do you primarily use these, in a studio or live setting?

Cheers.

Hi Viper,

Thank you for your kind words. I exclusively use these amps at home since sadly my band days are over for the time being.

Electron

[ElectronAvalanche]

Very Sexy!

Love your rack mount enclosures of choice...some of the highest quality I've ever seen outside of military data center rack mount gear. Out of curiosity...have you measured the S/N ratio in any of these preamps at higher gain levels? I'm curious as to how much hum is getting induced into the preamp circuitry from that in chassis mounted toroidal transformer. Might be negligible but you never know until you build it .

Which of course you have.

Hi GPD,

these preamps are very quiet and the s/n is excellent IMHO. I have not measured the s/n ratio. The toroidal transformer does not induce any hum into the circuit.

Best,

Electron

[ViperDoc]

Hi Viper,

Thank you for your kind words. I exclusively use these amps at home since sadly my band days are over for the time being.

Electron

If that's the case, you must have really had a good experience with your groups. That is awesome.

Alternatively, when I left my second-to-last band, I felt like a strongman concrete ball was lifted off of my unit, it was so painful. We had some good times, for sure, but once we got to recording an album of our own material, it became a narcissistic spotlight for the lead singer/guitarist who, incidentally, routinely nailed the sound of a cat being sodomized by a chainsaw with his guitar tone. The takes were worse than the mixes, it never came together, the bassist started re-recording some of my parts. OMG, what a nightmare. I just couldn't take it anymore. And I'm no Allan Holdsworth, but I can f8cking play, brother. At least better than a chainsaw!

The LAST band I played with was a strict Rush cover band, and everyone in that band was just awesome. We played some stellar gigs in a world class auditorium with smoke, lights, movie clips, all that. I put together a ridiculous pedal board that is featured on the Schmidt Array website. It has a touch of Strymon on it. Just a super badass experience for everyone. I wish I could play with them again, but alas, people move on.

Cygnus 5B Show.jpeg

Rush Gig Schmidt Array Board.pdf

Enjoy that amp, man. Sweet.