5C3/2 Vactrols

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QuantumMechanakillWave
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Post by QuantumMechanakillWave » Tue Jun 26, 2018 2:00 pm

I have reached out to my contact at X-Vive to acquire samples. I will post here when they arrive. Also, I am happy to do some tests, if anyone has original to which we can compare the results. :mmm:

I should also mention that I have had non-RoHS samples in the past, and they worked as expected in my project. -this is obviously not a very scientific statement, so I will acquire samples and we can go from there.
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Post by papz » Tue Jun 26, 2018 2:45 pm

Finest EMS gear service and Music Easel/208 goodies

I'm not a synths dealer and I'm not aware of an inexpensive Synthi secret market, please don't ask me if I know one for sale.
I don't offer support of any kind to people attempting to build clones of EMS equipment.

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Post by metasonix » Tue Jun 26, 2018 3:41 pm

From an email exchange, some more of what I think or have found (which ain't much):
> I am it sure how they managed the RoHS version. I wonder if they went through the legal process of getting an exemption for being irreplaceable, and are just charging a premium for those that are being listed as such..

Many companies have already tried--in 2013 the EU allegedly denied all of them, when phase 2 of the restrictions went into effect. They had allowed CdS cells in 2011 but supposedly removed the exemption later. Either OEMs meet the ROHS restrictions or they can't sell in the EU anywhere, period. No exceptions and no exemptions. It's a badly-written law for a world that is more complex than the EU regulators seem to be able to understand. I've been taking exemptions for leaded glass in vacuum tubes and the "Spare parts for electronic equipment in the market before July 1, 2006" thing, plus the kit exemption (for modules), and never had ANY problems shipping to Europe.

There are exemptions you could drive a locomotive thru. (Locomotives are exempt from ROHS because they are "motive equipment". Lead batteries are still okay for vehicles. Ha ha ha.)

Some other mfrs. of analog music gear have been having literal panic attacks over this and can't be convinced they aren't going to jail. (Even American ones!) I've told them they can always claim their synth modules are "kit parts requiring assembly", thus are exempt. Nope, they prefer to be paranoid. Go to NAMM and ask around at the "analog superbooth".

The "Cool Audio" guy (or is it the Macron guy, or are they the same company?) is claiming they have a vactrol that meets the "100 PPM or less by weight" regulation. I do not know if that is even possible, although CdS cells were always made by a cheap and wasteful process anyway, so it might be possible to make a cell with a very tiny amount of CdS.

There are websites full of blather about this, complete with the only "special exemptions" listed. Also read the Wikipedia article, which doesn't list all the exemptions but does have a "Criticism" section with valid info. It's difficult to Google it because there are dozens of outdated web pages.
http://www.rohsguide.com/rohs-categories.htm
https://en.wikipedia.org/wiki/Restricti ... #Criticism
There is an "official EU web page" that claims to list the ROHS exemptions. Good luck figuring them out:
http://ec.europa.eu/environment/waste/r ... gis_en.htm

Right there in the "consolidated version" it says:
Cadmium in photoresistors for analogue optocouplers applied in professional audio equipment
Expires on 31 December 2013

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QuantumMechanakillWave
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Post by QuantumMechanakillWave » Tue Jun 26, 2018 7:10 pm

papz wrote:Dave Brown already compared : https://modularsynthesis.com/vactrols/vactrols.htm
Awesome! :yay:
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Post by metasonix » Sat Jun 30, 2018 12:17 am

QuantumMechanakillWave wrote:
papz wrote:Dave Brown already compared : https://modularsynthesis.com/vactrols/vactrols.htm
Awesome!
I would say: nice, but not awesome. You will learn more about the quality of a vactrol by testing 50-100 sample pieces and plotting their voltage-to-resistance curves.

I just finished testing and matching 200 Silonexes from surplus. Obvious OEM rejects, they vary more than 2000% in v-r at a single test point. Such crap; 20% were too bad to use. Apply voltage to the LED and watch the cell resistance slowly drift upwards forever. Some had no LED polarity markings and a few were marked backwards. Makes you want to hate Canadians, eh?

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Post by cygmu » Sat Jun 30, 2018 12:26 am

I still don't know who makes the ones that Modular Addict sells, how they perform, or whether they contain cadmium, but here is an excerpt from an exchange seen on Facebook between Logan Erickson (who works at Modular Addict) and a potential buyer:
Buyer: They just say "not xVive" on them. Any ideas what make they are?
Logan: We have them made for us to spec
Buyer: Oh right - so like for like with excelitas then?
Logan: Huh? I don’t understand the question. We used the old spec sheet of what everyone wants. And said... “make them to this spec and consistent” the rest is IP I can’t talk bout.
The lack of information around these is a bit odd and doesn't fill me with confidence but surely if someone has a strong need for these parts it might be worth investigating.

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Post by monstrinho » Sat Jun 30, 2018 12:32 am

cygmu wrote:I still don't know who makes the ones that Modular Addict sells, how they perform, or whether they contain cadmium, but here is an excerpt from an exchange seen on Facebook between Logan Erickson (who works at Modular Addict) and a potential buyer:
Buyer: They just say "not xVive" on them. Any ideas what make they are?
Logan: We have them made for us to spec
Buyer: Oh right - so like for like with excelitas then?
Logan: Huh? I don’t understand the question. We used the old spec sheet of what everyone wants. And said... “make them to this spec and consistent” the rest is IP I can’t talk bout.
The lack of information around these is a bit odd and doesn't fill me with confidence but surely if someone has a strong need for these parts it might be worth investigating.
The bit about “...the rest is IP...” is very, very odd. It’s an LDR and an LED in a sealed package. Not rocket science. How much “IP” is there, really?

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Post by av500 » Sat Jun 30, 2018 1:17 am

monstrinho wrote: The bit about “...the rest is IP...” is very, very odd. It’s an LDR and an LED in a sealed package. Not rocket science. How much “IP” is there, really?
because it's just an LDR and a LED anybody can make them consistently up to specs, right?

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Post by metasonix » Sat Jun 30, 2018 6:47 pm

av500 wrote:
monstrinho wrote:The bit about “...the rest is IP...” is very, very odd. It’s an LDR and an LED in a sealed package. Not rocket science. How much “IP” is there, really?
because it's just an LDR and a LED anybody can make them consistently up to specs, right?
Anyone can make them. They are low-tech except for the LED which is readily available on open markets anyway. Any patents ran out long ago.

Logan is just being "mysterious" about his precious circuit designs, something that you see routinely from certain people in the modular world (which is full of crass and blatant copying from vintage designs, not to mention DSP-based modules which would be very easy to reverse-engineer). None of this shit is "secret" or even that difficult to duplicate.

It reminds me that lately I haven't seen very much of the miserable old tricks of the past, like potting circuits in plastic resin (ARP did a lot of that) and sandpapering numbers off semiconductors (Technosaurus and Sherman). It doesn't stop a determined thief from reverse-engineering but it DOES discourage repair and make customers angry.

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Post by Don T » Sun Jul 01, 2018 5:22 am

metasonix wrote: Logan is just being "mysterious" about his precious circuit designs, something that you see routinely from certain people in the modular world (which is full of crass and blatant copying from vintage designs, not to mention DSP-based modules which would be very easy to reverse-engineer). None of this shit is "secret" or even that difficult to duplicate.
Funny hearing L.E. comment on "IP" as if it's something to be protected, but I'd probably better stop this comment here...

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Post by appliancide » Sun Jul 01, 2018 11:59 am

metasonix wrote: It reminds me that lately I haven't seen very much of the miserable old tricks of the past, like potting circuits in plastic resin (ARP did a lot of that) and sandpapering numbers off semiconductors (Technosaurus and Sherman). It doesn't stop a determined thief from reverse-engineering but it DOES discourage repair and make customers angry.
Actually, it appears that randomsource are doing this on their semi-DIY Serge PCBs:

viewtopic.php?t=202866

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Post by snufkin » Mon Jul 02, 2018 3:27 am

appliancide wrote:
metasonix wrote: It reminds me that lately I haven't seen very much of the miserable old tricks of the past, like potting circuits in plastic resin (ARP did a lot of that) and sandpapering numbers off semiconductors (Technosaurus and Sherman). It doesn't stop a determined thief from reverse-engineering but it DOES discourage repair and make customers angry.
Actually, it appears that randomsource are doing this on their semi-DIY Serge PCBs:

viewtopic.php?t=202866
The peoples sanda-sizer :hihi:

Also it's annoying modular addict wont just come out and say they are having one of the current manufacturers skim off the most adherent vactrols or whatever. I would never purchase from a supplier that doesn't make it clear what the parts they are selling actually are.

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Post by BugBrand » Mon Jul 02, 2018 4:41 am

metasonix wrote:I just finished testing and matching 200 Silonexes from surplus. Obvious OEM rejects, they vary more than 2000% in v-r at a single test point. Such crap; 20% were too bad to use. Apply voltage to the LED and watch the cell resistance slowly drift upwards forever. Some had no LED polarity markings and a few were marked backwards. Makes you want to hate Canadians, eh?
Somehow about 10+ years ago I was in contact with the original silonex designer and I remember him commenting how the spec was so wide you could drive a bus through it.

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Post by snufkin » Tue Jul 03, 2018 1:38 am

BugBrand wrote:
metasonix wrote:I just finished testing and matching 200 Silonexes from surplus. Obvious OEM rejects, they vary more than 2000% in v-r at a single test point. Such crap; 20% were too bad to use. Apply voltage to the LED and watch the cell resistance slowly drift upwards forever. Some had no LED polarity markings and a few were marked backwards. Makes you want to hate Canadians, eh?
Somehow about 10+ years ago I was in contact with the original silonex designer and I remember him commenting how the spec was so wide you could drive a bus through it.
:hihi:

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Post by metasonix » Tue Jul 03, 2018 3:11 pm

Missed this Paul Schreiber FB post from March:
Now that I have "formal proof" of a RoHS compatible dual Vactrol that is "real" (in sampling), I am considering making a Euro version of the MOTM-401 Triple Resonant filter.

The filter has 3 independent BP filters and a dual VC-LFO. The circuit is based on the Korg PS-3100 'resonator section'.

The main issue is cost of the aforementioned dual Vactrols, and 3 per module is required. This is a large 'up-front' investment because I can't use them in another module, and not exactly eBay surplus either. I have to order from China directly is my guess (again, not exactly a Mouser top seller).

The only thing 'close' is the Mannequins '3 Sisters' but that lacks the dual LFO and not Vactrol (I think). Plus, I didn't design it so there's that factor :)

There are many MOTM-410 demos on YouTube, here is one that has fancy Keysight scope showing the results, plus the video goes over different sounds. JL Rice has several as well.

The price at retail would be about the same as the E440 filter.

Thoughts?


It re-appeared in my feed, because of an update today:
Phaedrus Dk Any news on THIS, Paul? :-)

Paul T Schreiber no, I will ping them but it appears to have died off (sadly)
So much for THAT.

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Post by metasonix » Mon Jul 16, 2018 4:11 pm

I'm still willing to make a group buy of Xvive 5C3/2s with anyone. I can front the money but want some positive responses first.

PS: any ideas on how to build a small music keyboard with off-shelf parts would be welcome. I'd make a "flagship" mono synth, except for pesky problems like people wanting it to be totally plug-in-and-play and self contained. It has to look at least vaguely like a piano keyboard to keep people happy. Fatar wants too much $ and their products are all wired for matrix scanning, I'd prefer to have a single-bus scheme instead.

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Post by QuantumMechanakillWave » Tue Jul 17, 2018 8:37 am

I have received the X-Vive samples. I will be doing some tests over the next couple of weeks. Let me know if there are any tests that you would like me to try. I only have 4 of each of the following:

5c3
5c3 RoHS
5c3/2

I guess they HAVE NOT made an RoHS 5c3/2.. I misunderstood what she had said. :doh:
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Post by metasonix » Sat Jul 21, 2018 10:59 pm

QuantumMechanakillWave wrote:I have received the X-Vive samples. I will be doing some tests over the next couple of weeks. Let me know if there are any tests that you would like me to try.
Check them for consistency from sample to sample--that's prob. more important than anything else for manufacturing.

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Post by QuantumMechanakillWave » Sun Jul 22, 2018 1:13 pm

Will do. I also plan to plot their response to changing voltages
metasonix wrote:
QuantumMechanakillWave wrote:I have received the X-Vive samples. I will be doing some tests over the next couple of weeks. Let me know if there are any tests that you would like me to try.
Check them for consistency from sample to sample--that's prob. more important than anything else for manufacturing.
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Post by metasonix » Thu Sep 20, 2018 4:13 am

Bumping--well, did you test those samples?

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Post by QuantumMechanakillWave » Thu Sep 20, 2018 8:49 am

Unfortunately not! Working through a number of family issues. I should be back into the DIY groove very soon! They did not send samples of RoHS 5c3/2, but she said that she would look into it. Also, she did mention that she would be fine with 100pc orders of 5c3/2’s.
metasonix wrote:Bumping--well, did you test those samples?
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Post by fuzzbass » Thu Sep 20, 2018 1:49 pm

I'm not nearly as versed in vactrols as you folks are. Recently I started repairing an old and somewhat odd Mesa Boogie amp that has four vactrols. These are used as silent switching elements (like channel switching, but this amp has only one channel, and the vactrols reprogram the circuit for high gain). All four vactrols are different, but I think they were all grabbed from a pile, since this amp just wants them ON or OFF and not in between.

Maybe the crummy documentation for vactrols has something to do with the legacy vactrol market generally not caring about all the interim states, the way we do.

Just a thought.
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Post by metasonix » Sat Sep 22, 2018 11:40 pm

fuzzbass wrote:I'm not nearly as versed in vactrols as you folks are. Recently I started repairing an old and somewhat odd Mesa Boogie amp that has four vactrols. These are used as silent switching elements (like channel switching, but this amp has only one channel, and the vactrols reprogram the circuit for high gain). All four vactrols are different, but I think they were all grabbed from a pile, since this amp just wants them ON or OFF and not in between.
Please, don't start me on Mesa-Boogie. Randall Smith owns patents on the use of vactrols to either switch functions in tube guitar amps, or as linear elements to allow "presets" in a tube preamp circuit. He spent a lot of money to get those patents and a lot more to sue people who copied his circuit designs. In the 1970s and 80s there were dozens of attempted copycat makers.

Here's a list of his patents, which I don't think is complete. Note how stupid/trivial many of these ideas are. "It's perfectly legal" to take out patents on trivial ideas.
http://mesaboogie.com/support/patents.html

And he's still taking out new ones.....
https://patents.justia.com/assignee/mesa-boogie

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Post by DSC » Sun Sep 23, 2018 7:22 am

metasonix wrote:I'm still willing to make a group buy of Xvive 5C3/2s with anyone. I can front the money but want some positive responses first.
You still down for a group buy? Any idea on pricing?

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Post by metasonix » Fri Oct 26, 2018 7:55 pm

DSC wrote:You still down for a group buy? Any idea on pricing?
Yes, and can you get some other prospective customers? I think they will end up costing DIYers about $7 apiece. (please, find me a cheaper source!!)

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