noticeable effect on tone using sockets instead of direct solder joints?

[mikepukmel]

Its quite a vague question, but read someplace that some small boutique pedal makers don't use sockets for transistors and most IC's. I can see for cost, but what about sound? Is the added inductance, resistance, capacitance enough to change the tone character on some of these old circuits (e.g. Fuzz Face, Klon centaur clones, compressors, etc).?

[nosaj]

Once you've locked in what you want to use a socket is just another cost factor. They don't necessarily market to people like us. Who like to tinker.

nosaj

[Enzo]

Pedals are on the floor, you stomp on them and kick them around. Sockets would just be one more connection to become unreliable. Pedals are built to use, not to screw around with inside, there is no need at all for a socket inside. Inductances, capacitances, and resistances are so incredibly tiny compared to the circuits, any change would be mostly imaginary.

[mikepukmel]

Cool, thanks.

[Mick Bailey]

Where you can get a change in sound is where contact resistance builds up over time and this can result in lower gain, noise or other problems. I see this quite a bit with old studio gear where sockets are used and a squirt of contact cleaner and re-seating the component restores function. Older contacts are sometimes either bare copper alloy or tinned, and along with a tinned component leg can result in long-term unreliability of the contact.

Additionally, if you use NOS transistors in sockets they can have tarnished leads which isn't a good situation to begin with, even if you clean up the leads. I have an old fuzz with socketed AC128 transistors that had stopped working due to contact resistance. As well as creeping resistance increase, there's the possibility of oxides causing a rectifying junction in parallel with the resistance which can cause additional sonic issues.

[mikepukmel]

Awesome info. Thanks everyone. So, sockets themselves negligible effect but connections might not age well. Sounds like I should just solder the parts in.

I had made two of a few different pedals to see if I could actually hear a difference, side by side, in some suggested parts changes. The Klon Centaur clone, builders suggested a few different clipping diodes. Wow, what a difference. Not even the same ballpark. one is a lot more crisp and gainy, the other one, more muddy with a less gain. Looking for other diodes to try out.

The Fuzz Face, I only got one build done, the other one is about 3/4 the way there. (before work/life balance fell apart) I wanted to try out a few different transistors.

Re AC128,Mick, the more I read, the more confused I get. Some build pages say "That pedal used AC128's". Then some interview with the original designer, can't remember his name, said he bought a whole bunch of diodes back in the day, after a long search for what sounded best, but (he said) just because they were labelled AC128 didn't mean they all sounded the same. Okay, so what now? I found a few "new old stock" mostly Russian made. There was a guy who sold some from the Czech republic, but doesn't advertise them anymore so maybe he sold out.

One of the kit guys said to buy 'a whole bunch' and measure them. So I have a very small bit of background with power diodes, I worked for a company that manufactured them, back in the early 90's. Pretty cool thing I got to run the curve tracer and a bunch of other test equipment and "see" what the differences were. They were basically looking for minimum values if they were above that, job done. But I can imagine with product variation part to part, what difference they might cause in an audio circuit.

And on and on.
(Audio is way more fun than power supplies!!!)

[mikepukmel]

I haven't found a pedal yet that makes me play like Stevie Ray or Jeff Beck. Still looking.

[nosaj]

Please read
http://www.geofex.com/article_folder...ace/fffram.htm

I swear RG had an article somewhere where you could use whatever transistor out of the batch and biasing it for what you wanted. But can't seem to find it.
nosaj

[Enzo]

If you build a circuit with the idea of changing a bunch of parts around to experiment, then by all means use sockets. But to just build something out the door, I avoid them.

[Mick Bailey]

Re AC128,Mick, the more I read, the more confused I get. Some build pages say "That pedal used AC128's". Then some interview with the original designer, can't remember his name, said he bought a whole bunch of diodes back in the day, after a long search for what sounded best, but (he said) just because they were labelled AC128 didn't mean they all sounded the same. Okay, so what now? I found a few "new old stock" mostly Russian made. There was a guy who sold some from the Czech republic, but doesn't advertise them anymore so maybe he sold out.

Yes - there's a lot of variation in gain and leakage. I have some that are unusable in most pedals due to leakage, and some where the gain is just way too low or are just really noisy. The best germanium transistors I've found have been the Russian ones. Reputable sellers have batches where the gain is in a decent range (above 100). The Russian manufacture is different somehow because they exhibit silicon-type leakage and temperature stability, but with a B-E voltage drop of around 0.2v. Russian manufacturers continued to make Ge transistors long after the rest of the world finished, so maybe they continued to develop the materials and processes.

[Mark Hammer]

I use a product called Stabilant 22. It is a contact enhancer (NOT cleaner) that used to be sold to audiophiles under the trade name "Tweak". It is a viscous electroconductive polymer whose ways are a complete mystery to me but which I have used for some 15 years to great success. The best description I can give is that it works like a liquid solder joint. It is bloody expensive (e.g., https://www.micro-tools.com/products/22 ) but it only takes sesame-seed-sized droplets to achieve remarkable results. I have restored and "de-crackled" all sorts of things that have a mechanical point-of-contact with the stuff. The reason why I mention it here is because I recall restoring a pedal whose functioning had become erratic by putting a tiny droplet on each pin of the sockets on the board. One could desolder all the sockets and replace them, I suppose, but that would have been a lot of work and risked damaging the board. Applying a teensy bit with the little plastic applicator wand was a whole lot easier.

[tedmich]

I use a product called Stabilant 22.

well Mark since you've been singing this stuffs praises for YEARS, I looked again at some of their newer SDS. They published the specific gravity and viscocity as well as its approx. MW (2800Da) and its refractive indices, so there is now no doubt...

I can state definitively it is BASF's Pluronic L-81, sold at a markup of >4060%
here is a 250mL bottle for $55.40
https://www.sigmaaldrich.com/catalog...g=en&region=US

[Mark Hammer]

well Mark since you've been singing this stuffs praises for YEARS, I looked again at some of their newer SDS. They published the specific gravity and viscocity as well as its approx. MW (2800Da) and its refractive indices, so there is now no doubt...

I can state definitively it is BASF's Pluronic L-81, sold at a markup of >4060%
here is a 250mL bottle for $55.40
https://www.sigmaaldrich.com/catalog...g=en&region=US

Hey, if it can be obtained more inexpensively in some other form, I'm all for that, since it would result in more users and greater community benefit. Although, since roughly 5ml has done me nicely for the past 15 years, 250ml is probably a wee bit more than I might need.

Not that I want to get into any debate, but perhaps Stabilant also includes other elements/additives that render it better suited to electrical contacts. If I start googling Pluronic L-81, the overwhelming majority of hits are related to surfactant properties in a medical context, potential anti-diabetic applications, and such. Nothing obviously related to electromechanical applications. So, while it may well contain Pluronic L-81 (and I lack any chemical expertise in such matters, so I can't and won't dispute what you posted) nothing I'm seeing would suggest its specific application to electromechanical contacts relies solely on that.

Price-point so often varies as a function of factors other than production and distribution costs, so I won't defend Stabilant's price-point. It might be conservative, or it might be extravagant; I can't tell. As a point of interest, I bought my own "personal collection" in a bin of half-ml "trial vials" for 50 cents apiece, doling them out as gifts to people with repair benches unfamiliar with it. Sadly, the local electronics distributor I bought them from has been out of business for about a decade.

But, to keep us back on track, use sockets where recommended, kids. And if you do, machined sockets with the round pins are more reliable and hardier than the cheaper ones with folded metal pins.

[Helmholtz]

I can state definitively it is BASF's Pluronic L-81, sold at a markup of >4060%
here is a 250mL bottle for $55.40
https://www.sigmaaldrich.com/catalog...g=en&region=US

So it's not conductivev?

http://www.stabilant.com/SDS_S22A_EN_2018-02-12.pdf

Edit: Just found this
https://cdn.shopify.com/s/files/1/07...plications.pdf

and
http://store.caig.com/s.nl/ctype.KB/...1977/KB.215/.f

[tedmich]

Stabilant 22 is not conductive, they list no other additives, even as "proprietary" which is required if its not fully described by the CAS number (which is CAS 9003-11-6, exactly that of the Pluronic series) See here: http://www.stabilant.com/SDS_S22__EN_2018-02-12.pdf

The real tell is its refractive indices which is exact to 3 decimal places for Pluronic L-81, any additive that has zero effect on this is strictly voodoo

There only variations on the central Stabilant 22 product is a 25% solution in IPA (22A) and ethanol (22E) and Pluronic L-81 is expected to be exactly this soluble in these alcohols. Even the cloud point matches up, which is an esoteric surfactant spec. A side note: I am, as some may know, a professional Chemist with a Ph.D.

But the only true test is a double blind!

Who wants to shell $55 for the 250mL? I volunteer to blind the samples and (if supported by data) aliquot the Pluronic L-81 into 50 x 5mL bottles labeled Stabilant 22 we can then sell for... $2500?