SSS Filters? The quest for...

[ElectronAvalanche]

Will the real SSS Filters please stand up?

So there are at least 3 versions circulating.

#1:

is from the handdrawn SSS 002 schematic. It shows a 0.1 and a 0.001 in parallel from the 1B tube. The 0.1 uF goes into a 100k and then into the SP-118 (0.65H or 0.39H) coil. The 0.001 goes into a 470K and from the junction of these to the high filters. The low filters go from the junction of the 470K to the other side of the coil. See first attachment.

#2:

is from the SSS-002 "may contain errors" computer generated schematic. This one simply has the 0.001 and a 0.01 uF cap from the 1B anode in parallel with the 0.01 going to the coil and the 0.001 going to a 470k and to the high filters. Low filters are fed from the coil-470k junction.

#3:

presumably from a 004 schematic. Having a single 0.05 from the 1B anode feeding a 100k//0.001 to a 0.9H coil (after coil 150k to high filters) and a 0.005 (Low filters).

So which one is the right one?

004 would make the most sense to me, but 002 handdrawn is from a schemo that seems to be legit.

Can anyone shed some light on this?

Thanks, Electron

[mhartman]

For the 002 filters, go with the hand drawn schematic (or it is the same as the filter setup from my layout: https://tubeamparchive.com/viewtopic.ph ... ht=sss+002 ). The hand drawn comes from a guy who spent a lot of time inside the real amp.

That being said, from what I've seen, the filter section on each SSS is setup differently. I've seen 3 different setups -- some have inductors, some don't. Those that have inductors have differing values.

So, there is no one "real" setup.

All of that being said, the SSS04 setup that you posted, as far as I can see, is wrong.

Hope that this helps.

[ElectronAvalanche]

Hi Mike,

thanks for the clarification. So as always Dumble seems to not have stuck to a specific schematic.

I will try the 002 version as per your layout. Thanks again for making that available!

Electron

[tictac]

this is the one I drew from the hand drawn schematic....

I recall someone saying they did some Spice simulations and that the circuit worked the same with or without the inductor.

I'vve used this circuit without the inductor and found both filters to function acceptably as high & low frequency tone shapers.

TT

[ElectronAvalanche]

Hi TicTac,

thanks for your answer and for the filter section redraw of the handdrawn schematic.

So it seems the inductor is not really necessary. I wonder why HAD used it at all then. There must be something else we might be missing.

I wish there was a video of a SSS amp where the filters are stepped through so one could get an idea how much effect these have.

Electron

[dreric]

Hi TicTac,

thanks for your answer and for the filter section redraw of the handdrawn schematic.

So it seems the inductor is not really necessary. I wonder why HAD used it at all then. There must be something else we might be missing.

I wish there was a video of a SSS amp where the filters are stepped through so one could get an idea how much effect these have.

Electron

I've got my #002 build up and running, still want to teak a few things. I've also played one of Sebago sounds #002.

My impressions so far.

The circuit is remarkably sensitive to guitar choice, strongly favors single coils. Tube choice in V1 has a big impact. I'm still experimenting.

The filters are cool and allow some great options the high filter ( caps) is more apparent than the low (resistors) the definitely work and impact the sound. Very much like a varitone.

As to the inductor no inductor, I used an inductor..............

[Aaron]

AFAIK, the one marked 004 was a guesstimate done by Bill and Tony and was from the SSS001 picture. I think this was done before the hand drawn was made public. (They would have to clarify).

Also, AFAIK SSS004 has the pot before the filter circuit. So there's another version!

And from memory, I think Brandon was in a SSS that had no inductor!

Cheers,
Aaron

[mhartman]

In addition to the different front end circuits and on-switch filter setups, some of rotary switches are setup to attenuate frequencies clockwise and others attenuate the frequencies counter-clockwise. Also, as previously discussed around here, some of the switches are 6 position, some are 7 position and others are 11.

It seems that there are almost as many SSS filter setups as there are phase-inverter setups.

[mhartman]

Here's a quick iphone demo to give you an idea of the SSS filters. The sound sucks and I realized afterwards that the gain was set way lower than it should have been, but this will let you hear the filters a bit (6 position non-inductor setup).

http://youtu.be/VeP8fXEQT74

By the way, I just uploaded it from my phone, so it might take a few minutes to show up.

[ElectronAvalanche]

Hi Mike,

thank you for taking the time to do this vid! Really appreciated.

So the high filters do indeed have a large impact on the sound. I do not hear as much effect from the low filters, but that might be my laptop speakers. I will listen with headphones.

So the amp in the vid has the 002 filter section with the inductor and the filter layout as posted by TicTac and as per your SSS layout?

What is the Hartman amp on the left?

Again thank you!

Electron