Designing for parts?

[alanp]

Let me first say that I love pedals like the Rangemaster, and the Fuzzface.

But I can't help but think that designing PCBs for rare, out of production parts like the CA3080 is somewhat irresponsible, if you can use a part still in production, like the LM13700, in the case of the CA3080. Also, I'm not talking about projects already in existance, like Rangemaster PCBs, or even Music Easel projects.

Some parts, like the germanium parts used in fuzzes, it's more murky, for me. On the one hand, more germanium parts are not being made, so we're gonna run out eventually. On the other hand... silicon just doesn't sound the same, especially the diodes.

There is some light at the end of the tunnel, especially in the synth world, where Alfa Rpar, Xvive, and CoolAudio are making old, once-rare parts like the Curtis Electro-Music chips, and the old bucket brigade delay chips. Not to mention vactrols!

But... with the rising instances of buying rare chips from ebay, and getting either scammed, or getting dead chips, I'm on the fence about designing for parts that are not in production anymore.

[Scruffie]

I do it on a case by case basis and have always tried to take component scarcity in to consideration and project desirability.

I'm not going to be designing boards to use the SAD1024, when Lectric started we did do MN3007 based boards as they were still in plentiful supply on the market but made sure to always add an 3207 option as I was aware that wouldn't be the case forever but since then thankfully, Xvive have started producing them again.

We recently included a CA3080 on the Downtown, that was mainly down to board space constrictions, but on occasion a circuit will need some redesigning to accommodate a LM13700 due to its 2 diode drops and people can be wary of overly modified circuits. But they were still being produced and sold through several legitimate suppliers and now Alfa are reissuing them, I see no reason not to use them, if anything, their use should be encouraged, we want these companies to do well!

Ebay purchases are down to the builder, I'd never recommend anyone buy from ebay unless they're set up to test for functionality and happy to take the risk, but I can't control someones purchasing ethics. Tayda have been known to sell faulty parts that are common and in production... you get what you pay for.

Germanium, I don't have a horse in that race.

[Thewintersoldier]

Thank you for addressing this. So many times I turned away from building a project because I saw that something was nearly impossible to find or a reissue part did not function the same in the circuit (xvive vtl5c4/2). I know tht some projects will simply be more expensive than others and if I decide to build it I'm ok with that but spending time to try and track down a rare part that is likely fake and I'll pass. Part of the reason I don't build some of the deadendfx projects I would love to. They even tell you in the build doc, which is cool of them and more than a lot of companies do. Just seems like a missed opportunity to make a board if I can't get the unicorn tears to make it work.

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[Aentons]

Tubes were in the same boat at one point but look at'em now

[culturejam]

On the one hand, more germanium parts are not being made, so we're gonna run out eventually.

There are some still being made. Actually, one of the places that makes them is really close to where I live. Here's where you can buy in small quantities: https://stompboxparts.com/new-jersey-semiconductor/

But yes, I generally agree with your post. I usually won't bother doing a PCB for anything that's rare or hard to source.

[CodeMonk]

On the one hand, more germanium parts are not being made, so we're gonna run out eventually.

There are some still being made. Actually, one of the places that makes them is really close to where I live. Here's where you can buy in small quantities: https://stompboxparts.com/new-jersey-semiconductor/

You buy anything from them yet?
Those 1N34a looks interesting.
But yes, I generally agree with your post. I usually won't bother doing a PCB for anything that's rare or hard to source.

[culturejam]

You buy anything from them yet?

I bought a pair of AC128s but haven't actually used them yet.

[CodeMonk]

You buy anything from them yet?

I bought a pair of AC128s but haven't actually used them yet.

I may just order some diodes this weekend.
I have some 1N34a I bought about 10 years ago to compare them to.

[culturejam]

I may just order some diodes this weekend.
I have some 1N34a I bought about 10 years ago to compare them to.

I actually just ordered some AC127s today, haha. I want to see how a NPN Ge Tonebender sounds.

[Jules]

I just had a npn and a pnp germanium mk11 Tone Bender set up last night to compare and dare I say it they should sound almost identical to my ear.
Gain and leakage being far more important.
That's my experience anyways

[Afonso]

Its kind of a compromise, I believe. Either we have to design a circuit that sounds better, but at the risk of not being able to find these rare vintage components in the long run. Or we stay more comfortable with components that are readily available, but sacrificing a bit of how it will sound.

I have heard about a chinese company (UTsource.net) that supposedly sells a lot of genuine, used vintage components that are salvaged from old stuff. However, I have never tried buying anything there. Have anyone heard of/tried buying stuff from them? Could that be true or is it just another scam?

[mauman]

I tried out UTSource, they have their own stock and are also a consolidator for other vendors, so you can choose what sources you get what parts from.  Shipping time and costs are reasonable.   I tested the parts I got against known good and authentic versions, and the performance was identical.  However, I was careful about which sources I selected, mostly UTSource themselves rather than their "marketplace" vendors (kind of like buying from Amazon vs. an Amazon Marketplace vendor of unknown origin.)  On some items, you have to do a request for quote (RFQ) and the vendor bids on your request, that can take a few days.  I've tested their CA3240AEZ and TDA7240AV with good results, also got some 2N5458 and 2N5459 that I still need to test.  So far so good, but YMMV. Mike

<EDIT> I just took another look, and their shipping policies have changed and ship prices are way up, economy shipping is no longer available.  Might be worth it for a big order?