SSS002 build log

[timrobertson100]

I'm about to put in an order for the final missing parts.
Does the GNFB resistor really need to be 2W please, or is that sized to reduce resistor noise? I'm struggling to find 2.7K 2W carbon films (I'll buy other values too to experiment)

[Colossal]

I'm about to put in an order for the final missing parts.
Does the GNFB resistor really need to be 2W please, or is that sized to reduce resistor noise? I'm struggling to find 2.7K 2W carbon films (I'll buy other values too to experiment)

Look for Kiwame 2W carbon film (hificollective UK).

[timrobertson100]

Thanks! Ordered

[timrobertson100]

Onto the last stretch.... power-up day

[Colossal]

Looks great! Very nice work.

[erwin_ve]

Nice Tim, looking forward to your findings.

Erwin

[pompeiisneaks]

Very cool, looking forward to see how it fires up.

~Phil

[timrobertson100]

Thanks all. Success! Another #002 inspired clone is created. Other than having to swap the OT leads it all seems to work (only had a short test so far).

There are 2 things I'd greatly appreciate feedback on:

Like others report, it seems a very quiet amp, but with both the bright and mid switches on I have increasing hiss when stepping up through the high filter (unusable). Knock both off, and the hiss goes away and it seems very usable, and I notice everyone seems to have mid/bright off on their demos.
I've never had so many settings on an amp - are there just combinations of things that don't "work"? I've been able to use the switches and the step filter in some configurations, but some "all-on" seems to be a no go.

This is using vibrolux iron, so should be somewhere around 35w. If I want to have the same GNFB ratio as the schematic, am I correct in thinking I would reduce the 2K7, or alternatively try on the 8 or 16 tap?

Thanks!

(p.s. anyone thinking of building one, but concerned it might be too hard - it really isn't with the PCB and chassis option from Erwin/Ryan)

[erwin_ve]

Thanks all. Success! Another #002 inspired clone is created. Other than having to swap the OT leads it all seems to work (only had a short test so far).

There are 2 things I'd greatly appreciate feedback on:

Like others report, it seems a very quiet amp, but with both the bright and mid switches on I have increasing hiss when stepping up through the high filter (unusable). Knock both off, and the hiss goes away and it seems very usable, and I notice everyone seems to have mid/bright off on their demos.
I've never had so many settings on an amp - are there just combinations of things that don't "work"? I've been able to use the switches and the step filter in some configurations, but some "all-on" seems to be a no go.

This is using vibrolux iron, so should be somewhere around 35w. If I want to have the same GNFB ratio as the schematic, am I correct in thinking I would reduce the 2K7, or alternatively try on the 8 or 16 tap?

Thanks!

(p.s. anyone thinking of building one, but concerned it might be too hard - it really isn't with the PCB and chassis option from Erwin/Ryan)

Congrats!
The only way I get hiss is; using the mid switch at the master volume (is bright cap on master).
When having a low setting(pre-amp)volume knob with the bright switch might result in hiss, put your pre-amp volume on 2 o clock. This would result in less effect of the bright cap.
The step filter is taste I dont have any hiss using various settings.
For the Gnfb resistor; you could try a parallel resistor to see if you like a smaller resistance?

[rccolgan]

Congrats, man! That's so exciting! I agree with your findings and Erwin's that the hiss really isn't present unless bright & mid-caps are engaged. I usually have both off and the amp is just perfect for my use & a Strat.

[talbany]

The only hiss I saw was a little coming off my reverb return amp. Other than that quiet on all settings.
I have mine crammed in an ODS chassis
Congrats! your pedals will never sound the same again
Tony

[timrobertson100]

Thanks all - I had some time to poke around this morning, and I spoke too soon - something definitely not right here with hiss, even though some settings sound OK.

With no input signal and hiss present, I find chopstick tapping suggests the cap on the deep bass is problematic (it thuds) so I'll swap that out.

I also spot something that looks suspicious on Ryan's layout on the step filter, which I copied, compared to a schematic I found somewhere. Is it missing the connection shown with the purple dash, please?
That would go some ways to explain why mine drops the hiss when on the 3000pF but not on the other steps (but not the cause of the hiss).

Thanks

[rccolgan]

Thanks all - I had some time to poke around this morning, and I spoke too soon - something definitely not right here with hiss, even though some settings sound OK.

With no input signal and hiss present, I find chopstick tapping suggests the cap on the deep bass is problematic (it thuds) so I'll swap that out.

I also spot something that looks suspicious on Ryan's layout on the step filter, which I copied, compared to a schematic I found somewhere. Is it missing the connection shown with the purple dash, please?
That would go some ways to explain why mine drops the hiss when on the 3000pF but not on the other steps (but not the cause of the hiss).

Thanks

hmm.. maybe! Have you experimented and made the purple dash connection for a test? I don't see that purple connection on the Japanese schematic or the Ceriatone SSS however I'm curious if you experiment. Mine is pretty dead quiet throughout the sweeps. Reverb does introduce some hiss. I have pretty much all TAD 7025 high grade in mine and a TAD 5751 in the reverb.

[timrobertson100]

Thanks for confirming Ryan (and for following)

I'm not sure where I got the schematic I printed earlier, but it's similar to the one you have on GitHub here. It looks like all those caps also ground through the 3000pF and not just at step 1 which prompted the question. It's good to see the Japanese schematic confirm the layout.

I did try the connection in the hope it was my hiss problem, but it was not. Grounding input to V1b and the hiss is all gone, so I've just borrowed a scope to try and isolate the cause which is upstream of that.

[timrobertson100]

Took me a while to diagnose this hiss which showed at all positions of the high filter except fully clockwise...

Turned out to be noise on b+. That was suppressed in that high filter position due to the 3000pF-to-ground engaged since it connects through to the plate of V1b.
Reflowing the power board solved the hiss (of course only after I'd tried several other fixes and slightly messed up a clean build. There isn't much room around the filters to solder in situ).

I'm still experimenting with GNFB but will get some sound clips up in a few days.