Vactrols for buchla LPG / VTL5C

[Funky40]

Hello,

somebody has postet ( in our german Synth/ modular forum ) something concerning to the Plan B LPG.
He said Peter grenader has changed his Vactrols in 2007 to faster ones,
and used to use VTL5C from parkin elemer which delivered a 200ms decay in the past.





My questions:
1. ) is VTL5C a name only used by perkin elmer ?
2.) or in other words: if i have VTL5C , are this allways the same with that long decay ?
3. ) Has VTL5 and VTL5C2 the same characteristics ?
4. ) are there big differences between them, should one test out different ones ?



I built my Fonik LPGs with VTL5C2 which i got from krisp4u from EM.
I'm happy with the sound of my Fonik LPGs but just like to know if i have original Buchlastyle charcteristics or not.

[Danno Gee Ray]

Maybe this will help?

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[Funky40]

lol,
no sorry. i hoped to get just a few words.
i have problems with datasheets and anyway to pic up informations on the net,
and especially when this is in "technical" form

but thanks for the help anyway, might be from interest for others

[Coriolis]

Yeah, Vtl5c3 and others (VTLxCx) are Perkin Elmer, and actuallly so is the word "vactrol"..
A company named Silonex has some called NSL32 which others have used in various circuits where a vactrol is used.
There was talk of a third manufacturer in a thread some time ago (last year)
called Macron. I think these were supposed to be faster than Perkin Elmer?
Anyway, I remember Peter Grenader (who is a member here) expressing interest in the Macron brand in that thread, so maybe he actually made the switch...who knows.

I do believe original LPG's used the VTL5C3/2, not the VTL5C2 though. The 5C3 is faster than the 5C2 I think...

C

[bubblechamber]

the problem with the faster vactrols is that you end up losing much of the characteristics of the slower ones, like the ringing and slower response time that kind of loosens up sequenced music. by using faster ones it becomes much more like a switch, more transparent. that might be good for some things, like guitar amps, but it will not give you the same sound and performance of the Buchla stuff Peter is coping.

[Coriolis]

Yeah, I don't quite see the point in faster vactrols either, seeing that there already is great sound to be had with the old types.
Now that I think about it, the thing that may have gotten Peter G excited about Macron was more to do with a higher off resistance or something - he mentioned something about how it might enable him to get an LPG to shut off completely that way.

Dunno - the samples I've heard (don't have one myself - yet) sound like they shut off fine...?

C

[Peake]

Fast Vactrols would likely be good in something like the Korg MS50 "modulation amp", which is a DC-capable, voltage-controlled circuit, for using mod wheels to introduce LFOs for vibrato, etc.

Although slower ones might just be charming in that sort of circuit...

[Funky40]

thank you folks
my primary questions are answered.
I built my Fonik LPG with VTL5C3/2 ( wrote it wrong above )
this are btw. the first VCAs in my modularsystem which i like.
So it seems that i have "that" Buchla sound.

my "fear" was that it could be better